WorldWideScience

Sample records for zebra finch syrinx

  1. The songbird syrinx morphome: a three-dimensional, high-resolution, interactive morphological map of the zebra finch vocal organ

    Directory of Open Access Journals (Sweden)

    Düring Daniel N

    2013-01-01

    Full Text Available Abstract Background Like human infants, songbirds learn their species-specific vocalizations through imitation learning. The birdsong system has emerged as a widely used experimental animal model for understanding the underlying neural mechanisms responsible for vocal production learning. However, how neural impulses are translated into the precise motor behavior of the complex vocal organ (syrinx to create song is poorly understood. First and foremost, we lack a detailed understanding of syringeal morphology. Results To fill this gap we combined non-invasive (high-field magnetic resonance imaging and micro-computed tomography and invasive techniques (histology and micro-dissection to construct the annotated high-resolution three-dimensional dataset, or morphome, of the zebra finch (Taeniopygia guttata syrinx. We identified and annotated syringeal cartilage, bone and musculature in situ in unprecedented detail. We provide interactive three-dimensional models that greatly improve the communication of complex morphological data and our understanding of syringeal function in general. Conclusions Our results show that the syringeal skeleton is optimized for low weight driven by physiological constraints on song production. The present refinement of muscle organization and identity elucidates how apposed muscles actuate different syringeal elements. Our dataset allows for more precise predictions about muscle co-activation and synergies and has important implications for muscle activity and stimulation experiments. We also demonstrate how the syrinx can be stabilized during song to reduce mechanical noise and, as such, enhance repetitive execution of stereotypic motor patterns. In addition, we identify a cartilaginous structure suited to play a crucial role in the uncoupling of sound frequency and amplitude control, which permits a novel explanation of the evolutionary success of songbirds.

  2. Female Zebra Finches Smell Their Eggs.

    Directory of Open Access Journals (Sweden)

    Sarah Golüke

    Full Text Available Parental investment in unrelated offspring seems maladaptive from an evolutionary perspective, due to the costs of energy and resources that cannot be invested in related offspring at the same time. Therefore selection should favour mechanisms to discriminate between own and foreign offspring. In birds, much emphasis has been placed on understanding the visual mechanisms underlying egg recognition. However, olfactory egg recognition has almost been completely ignored. Here, we investigated whether female zebra finches (Taeniopygia guttata are able to discriminate between their own and a conspecific egg based on olfactory cues alone. Zebra finches are colonial-breeding songbirds. Eggs are monomorphic, i.e. without any spotting pattern, and intraspecific brood parasitism frequently occurs. In a binary choice experiment, female zebra finches were given the choice between the scent of their own and a conspecific egg. After the onset of incubation, females chose randomly and showed no sign of discrimination. However, shortly before hatching, females preferred significantly the odour of their own egg. The finding that females are capable to smell their own egg may inspire more research on the potential of olfaction involved in egg recognition, especially in cases where visual cues might be limited.

  3. Fitness consequences of polymorphic inversions in the zebra finch genome.

    Science.gov (United States)

    Knief, Ulrich; Hemmrich-Stanisak, Georg; Wittig, Michael; Franke, Andre; Griffith, Simon C; Kempenaers, Bart; Forstmeier, Wolfgang

    2016-09-29

    Inversion polymorphisms constitute an evolutionary puzzle: they should increase embryo mortality in heterokaryotypic individuals but still they are widespread in some taxa. Some insect species have evolved mechanisms to reduce the cost of embryo mortality but humans have not. In birds, a detailed analysis is missing although intraspecific inversion polymorphisms are regarded as common. In Australian zebra finches (Taeniopygia guttata), two polymorphic inversions are known cytogenetically and we set out to detect these two and potentially additional inversions using genomic tools and study their effects on embryo mortality and other fitness-related and morphological traits. Using whole-genome SNP data, we screened 948 wild zebra finches for polymorphic inversions and describe four large (12-63 Mb) intraspecific inversion polymorphisms with allele frequencies close to 50 %. Using additional data from 5229 birds and 9764 eggs from wild and three captive zebra finch populations, we show that only the largest inversions increase embryo mortality in heterokaryotypic males, with surprisingly small effect sizes. We test for a heterozygote advantage on other fitness components but find no evidence for heterosis for any of the inversions. Yet, we find strong additive effects on several morphological traits. The mechanism that has carried the derived inversion haplotypes to such high allele frequencies remains elusive. It appears that selection has effectively minimized the costs associated with inversions in zebra finches. The highly skewed distribution of recombination events towards the chromosome ends in zebra finches and other estrildid species may function to minimize crossovers in the inverted regions.

  4. Selective auditory grouping by zebra finches: testing the iambic-trochaic law.

    Science.gov (United States)

    Spierings, Michelle; Hubert, Jeroen; Ten Cate, Carel

    2017-07-01

    Humans have a strong tendency to spontaneously group visual or auditory stimuli together in larger patterns. One of these perceptual grouping biases is formulated as the iambic/trochaic law, where humans group successive tones alternating in pitch and intensity as trochees (high-low and loud-soft) and alternating in duration as iambs (short-long). The grouping of alternations in pitch and intensity into trochees is a human universal and is also present in one non-human animal species, rats. The perceptual grouping of sounds alternating in duration seems to be affected by native language in humans and has so far not been found among animals. In the current study, we explore to which extent these perceptual biases are present in a songbird, the zebra finch. Zebra finches were trained to discriminate between short strings of pure tones organized as iambs and as trochees. One group received tones that alternated in pitch, a second group heard tones alternating in duration, and for a third group, tones alternated in intensity. Those zebra finches that showed sustained correct discrimination were next tested with longer, ambiguous strings of alternating sounds. The zebra finches in the pitch condition categorized ambiguous strings of alternating tones as trochees, similar to humans. However, most of the zebra finches in the duration and intensity condition did not learn to discriminate between training stimuli organized as iambs and trochees. This study shows that the perceptual bias to group tones alternating in pitch as trochees is not specific to humans and rats, but may be more widespread among animals.

  5. Zebra finches are sensitive to prosodic features of human speech.

    Science.gov (United States)

    Spierings, Michelle J; ten Cate, Carel

    2014-07-22

    Variation in pitch, amplitude and rhythm adds crucial paralinguistic information to human speech. Such prosodic cues can reveal information about the meaning or emphasis of a sentence or the emotional state of the speaker. To examine the hypothesis that sensitivity to prosodic cues is language independent and not human specific, we tested prosody perception in a controlled experiment with zebra finches. Using a go/no-go procedure, subjects were trained to discriminate between speech syllables arranged in XYXY patterns with prosodic stress on the first syllable and XXYY patterns with prosodic stress on the final syllable. To systematically determine the salience of the various prosodic cues (pitch, duration and amplitude) to the zebra finches, they were subjected to five tests with different combinations of these cues. The zebra finches generalized the prosodic pattern to sequences that consisted of new syllables and used prosodic features over structural ones to discriminate between stimuli. This strong sensitivity to the prosodic pattern was maintained when only a single prosodic cue was available. The change in pitch was treated as more salient than changes in the other prosodic features. These results show that zebra finches are sensitive to the same prosodic cues known to affect human speech perception. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  6. Analysis of CR1 Repeats in the Zebra Finch Genome

    Directory of Open Access Journals (Sweden)

    George E. Liu

    2013-06-01

    Full Text Available Most bird species have smaller genomes and fewer repeats than mammals. Chicken Repeat 1 (CR1 repeat is one of the most abundant families of repeats, ranging from ~133,000 to ~187,000 copies accounting for ~50 to ~80% of the interspersed repeats in the zebra finch and chicken genomes, respectively. CR1 repeats are believed to have arisen from the retrotransposition of a small number of master elements, which gave rise to multiple CR1 subfamilies in the chicken. In this study, we performed a global assessment of the divergence distributions, phylogenies, and consensus sequences of CR1 repeats in the zebra finch genome. We identified and validated 34 CR1 subfamilies and further analyzed the correlation between these subfamilies. We also discovered 4 novel lineage-specific CR1 subfamilies in the zebra finch when compared to the chicken genome. We built various evolutionary trees of these subfamilies and concluded that CR1 repeats may play an important role in reshaping the structure of bird genomes.

  7. Acoustic fine structure may encode biologically relevant information for zebra finches.

    Science.gov (United States)

    Prior, Nora H; Smith, Edward; Lawson, Shelby; Ball, Gregory F; Dooling, Robert J

    2018-04-18

    The ability to discriminate changes in the fine structure of complex sounds is well developed in birds. However, the precise limit of this discrimination ability and how it is used in the context of natural communication remains unclear. Here we describe natural variability in acoustic fine structure of male and female zebra finch calls. Results from psychoacoustic experiments demonstrate that zebra finches are able to discriminate extremely small differences in fine structure, which are on the order of the variation in acoustic fine structure that is present in their vocal signals. Results from signal analysis methods also suggest that acoustic fine structure may carry information that distinguishes between biologically relevant categories including sex, call type and individual identity. Combined, our results are consistent with the hypothesis that zebra finches can encode biologically relevant information within the fine structure of their calls. This study provides a foundation for our understanding of how acoustic fine structure may be involved in animal communication.

  8. Colour preferences in nest-building zebra finches.

    Science.gov (United States)

    Muth, Felicity; Steele, Matthew; Healy, Susan D

    2013-10-01

    Some bird species are selective in the materials they choose for nest building, preferring, for example, materials of one colour to others. However, in many cases the cause of these preferences is not clear. One of those species is the zebra finch, which exhibits strong preferences for particular colours of nest material. In an attempt to determine why these birds strongly prefer one colour of material over another, we compared the preferences of paired male zebra finches for nest material colour with their preferences for food of the same colours. We found that birds did indeed prefer particular colours of nest material (in most cases blue) but that they did not generally prefer food of one colour over the other colours. It appears, then, that a preference for one colour or another of nest material is specific to the nest-building context. This article is part of a Special Issue entitled: insert SI title. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. The perception of regularity in an isochronous stimulus in zebra finches (Taeniopygia guttata) and humans

    NARCIS (Netherlands)

    van der Aa, J.; Honing, H.; ten Cate, C.

    2015-01-01

    Perceiving temporal regularity in an auditory stimulus is considered one of the basic features of musicality. Here we examine whether zebra finches can detect regularity in an isochronous stimulus. Using a go/no go paradigm we show that zebra finches are able to distinguish between an isochronous

  10. Gene duplication and fragmentation in the zebra finch major histocompatibility complex.

    Science.gov (United States)

    Balakrishnan, Christopher N; Ekblom, Robert; Völker, Martin; Westerdahl, Helena; Godinez, Ricardo; Kotkiewicz, Holly; Burt, David W; Graves, Tina; Griffin, Darren K; Warren, Wesley C; Edwards, Scott V

    2010-04-01

    Due to its high polymorphism and importance for disease resistance, the major histocompatibility complex (MHC) has been an important focus of many vertebrate genome projects. Avian MHC organization is of particular interest because the chicken Gallus gallus, the avian species with the best characterized MHC, possesses a highly streamlined minimal essential MHC, which is linked to resistance against specific pathogens. It remains unclear the extent to which this organization describes the situation in other birds and whether it represents a derived or ancestral condition. The sequencing of the zebra finch Taeniopygia guttata genome, in combination with targeted bacterial artificial chromosome (BAC) sequencing, has allowed us to characterize an MHC from a highly divergent and diverse avian lineage, the passerines. The zebra finch MHC exhibits a complex structure and history involving gene duplication and fragmentation. The zebra finch MHC includes multiple Class I and Class II genes, some of which appear to be pseudogenes, and spans a much more extensive genomic region than the chicken MHC, as evidenced by the presence of MHC genes on each of seven BACs spanning 739 kb. Cytogenetic (FISH) evidence and the genome assembly itself place core MHC genes on as many as four chromosomes with TAP and Class I genes mapping to different chromosomes. MHC Class II regions are further characterized by high endogenous retroviral content. Lastly, we find strong evidence of selection acting on sites within passerine MHC Class I and Class II genes. The zebra finch MHC differs markedly from that of the chicken, the only other bird species with a complete genome sequence. The apparent lack of synteny between TAP and the expressed MHC Class I locus is in fact reminiscent of a pattern seen in some mammalian lineages and may represent convergent evolution. Our analyses of the zebra finch MHC suggest a complex history involving chromosomal fission, gene duplication and translocation in the

  11. Gene duplication and fragmentation in the zebra finch major histocompatibility complex

    Directory of Open Access Journals (Sweden)

    Burt David W

    2010-04-01

    Full Text Available Abstract Background Due to its high polymorphism and importance for disease resistance, the major histocompatibility complex (MHC has been an important focus of many vertebrate genome projects. Avian MHC organization is of particular interest because the chicken Gallus gallus, the avian species with the best characterized MHC, possesses a highly streamlined minimal essential MHC, which is linked to resistance against specific pathogens. It remains unclear the extent to which this organization describes the situation in other birds and whether it represents a derived or ancestral condition. The sequencing of the zebra finch Taeniopygia guttata genome, in combination with targeted bacterial artificial chromosome (BAC sequencing, has allowed us to characterize an MHC from a highly divergent and diverse avian lineage, the passerines. Results The zebra finch MHC exhibits a complex structure and history involving gene duplication and fragmentation. The zebra finch MHC includes multiple Class I and Class II genes, some of which appear to be pseudogenes, and spans a much more extensive genomic region than the chicken MHC, as evidenced by the presence of MHC genes on each of seven BACs spanning 739 kb. Cytogenetic (FISH evidence and the genome assembly itself place core MHC genes on as many as four chromosomes with TAP and Class I genes mapping to different chromosomes. MHC Class II regions are further characterized by high endogenous retroviral content. Lastly, we find strong evidence of selection acting on sites within passerine MHC Class I and Class II genes. Conclusion The zebra finch MHC differs markedly from that of the chicken, the only other bird species with a complete genome sequence. The apparent lack of synteny between TAP and the expressed MHC Class I locus is in fact reminiscent of a pattern seen in some mammalian lineages and may represent convergent evolution. Our analyses of the zebra finch MHC suggest a complex history involving

  12. Ontogeny of adaptive antibody response to a model antigen in captive altricial zebra finches.

    Directory of Open Access Journals (Sweden)

    Tess L Killpack

    Full Text Available Based on studies from the poultry literature, all birds are hypothesized to require at least 4 weeks to develop circulating mature B-cell lineages that express functionally different immunoglobulin specificities. However, many altricial passerines fledge at adult size less than four weeks after the start of embryonic development, and therefore may experience a period of susceptibility during the nestling and post-fledging periods. We present the first study, to our knowledge, to detail the age-related changes in adaptive antibody response in an altricial passerine. Using repeated vaccinations with non-infectious keyhole limpet hemocyanin (KLH antigen, we studied the ontogeny of specific adaptive immune response in altricial zebra finches Taeniopygia guttata. Nestling zebra finches were first injected at 7 days (7d, 14 days (14d, or 21 days post-hatch (21d with KLH-adjuvant emulsions, and boosted 7 days later. Adults were vaccinated in the same manner. Induced KLH-specific IgY antibodies were measured using ELISA. Comparisons within age groups revealed no significant increase in KLH-specific antibody levels between vaccination and boost in 7d birds, yet significant increases between vaccination and boost were observed in 14d, 21d, and adult groups. There was no significant difference among age groups in KLH antibody response to priming vaccination, yet KLH antibody response post-boost significantly increased with age among groups. Post-boost antibody response in all nestling age groups was significantly lower than in adults, indicating that mature adult secondary antibody response level was not achieved in zebra finches prior to fledging (21 days post-hatch in zebra finches. Findings from this study contribute fundamental knowledge to the fields of developmental immunology and ecological immunology and strengthen the utility of zebra finches as a model organism for future studies of immune ontogeny.

  13. Zebra finch mates use their forebrain song system in unlearned call communication.

    Science.gov (United States)

    Ter Maat, Andries; Trost, Lisa; Sagunsky, Hannes; Seltmann, Susanne; Gahr, Manfred

    2014-01-01

    Unlearned calls are produced by all birds whereas learned songs are only found in three avian taxa, most notably in songbirds. The neural basis for song learning and production is formed by interconnected song nuclei: the song control system. In addition to song, zebra finches produce large numbers of soft, unlearned calls, among which "stack" calls are uttered frequently. To determine unequivocally the calls produced by each member of a group, we mounted miniature wireless microphones on each zebra finch. We find that group living paired males and females communicate using bilateral stack calling. To investigate the role of the song control system in call-based male female communication, we recorded the electrical activity in a premotor nucleus of the song control system in freely behaving male birds. The unique combination of acoustic monitoring together with wireless brain recording of individual zebra finches in groups shows that the neuronal activity of the song system correlates with the production of unlearned stack calls. The results suggest that the song system evolved from a brain circuit controlling simple unlearned calls to a system capable of producing acoustically rich, learned vocalizations.

  14. Exploring the zebra finch Taeniopygia guttata as a novel animal model for the speech-language deficit of fragile X syndrome.

    Science.gov (United States)

    Winograd, Claudia; Ceman, Stephanie

    2012-01-01

    Fragile X syndrome (FXS) is the most common cause of inherited intellectual disability and presents with markedly atypical speech-language, likely due to impaired vocal learning. Although current models have been useful for studies of some aspects of FXS, zebra finch is the only tractable lab model for vocal learning. The neural circuits for vocal learning in the zebra finch have clear relationships to the pathways in the human brain that may be affected in FXS. Further, finch vocal learning may be quantified using software designed specifically for this purpose. Knockdown of the zebra finch FMR1 gene may ultimately enable novel tests of therapies that are modality-specific, using drugs or even social strategies, to ameliorate deficits in vocal development and function. In this chapter, we describe the utility of the zebra finch model and present a hypothesis for the role of FMRP in the developing neural circuitry for vocalization.

  15. Song decrystallization in adult zebra finches does not require the song nucleus NIf.

    Science.gov (United States)

    Roy, Arani; Mooney, Richard

    2009-08-01

    In adult male zebra finches, transecting the vocal nerve causes previously stable (i.e., crystallized) song to slowly degrade, presumably because of the resulting distortion in auditory feedback. How and where distorted feedback interacts with song motor networks to induce this process of song decrystallization remains unknown. The song premotor nucleus HVC is a potential site where auditory feedback signals could interact with song motor commands. Although the forebrain nucleus interface of the nidopallium (NIf) appears to be the primary auditory input to HVC, NIf lesions made in adult zebra finches do not trigger song decrystallization. One possibility is that NIf lesions do not interfere with song maintenance, but do compromise the adult zebra finch's ability to express renewed vocal plasticity in response to feedback perturbations. To test this idea, we bilaterally lesioned NIf and then transected the vocal nerve in adult male zebra finches. We found that bilateral NIf lesions did not prevent nerve section-induced song decrystallization. To test the extent to which the NIf lesions disrupted auditory processing in the song system, we made in vivo extracellular recordings in HVC and a downstream anterior forebrain pathway (AFP) in NIf-lesioned birds. We found strong and selective auditory responses to the playback of the birds' own song persisted in HVC and the AFP following NIf lesions. These findings suggest that auditory inputs to the song system other than NIf, such as the caudal mesopallium, could act as a source of auditory feedback signals to the song motor network.

  16. The perception of regularity in an isochronous stimulus in zebra finches (Taeniopygia guttata) and humans.

    Science.gov (United States)

    van der Aa, Jeroen; Honing, Henkjan; ten Cate, Carel

    2015-06-01

    Perceiving temporal regularity in an auditory stimulus is considered one of the basic features of musicality. Here we examine whether zebra finches can detect regularity in an isochronous stimulus. Using a go/no go paradigm we show that zebra finches are able to distinguish between an isochronous and an irregular stimulus. However, when the tempo of the isochronous stimulus is changed, it is no longer treated as similar to the training stimulus. Training with three isochronous and three irregular stimuli did not result in improvement of the generalization. In contrast, humans, exposed to the same stimuli, readily generalized across tempo changes. Our results suggest that zebra finches distinguish the different stimuli by learning specific local temporal features of each individual stimulus rather than attending to the global structure of the stimuli, i.e., to the temporal regularity. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Oscillating magnetic field disrupts magnetic orientation in Zebra finches, Taeniopygia guttata

    Directory of Open Access Journals (Sweden)

    Wiltschko Wolfgang

    2009-10-01

    Full Text Available Abstract Background Zebra finches can be trained to use the geomagnetic field as a directional cue for short distance orientation. The physical mechanisms underlying the primary processes of magnetoreception are, however, largely unknown. Two hypotheses of how birds perceive magnetic information are mainly discussed, one dealing with modulation of radical pair processes in retinal structures, the other assuming that iron deposits in the upper beak of the birds are involved. Oscillating magnetic fields in the MHz range disturb radical pair mechanisms but do not affect magnetic particles. Thus, application of such oscillating fields in behavioral experiments can be used as a diagnostic tool to decide between the two alternatives. Methods In a setup that eliminates all directional cues except the geomagnetic field zebra finches were trained to search for food in the magnetic north/south axis. The birds were then tested for orientation performance in two magnetic conditions. In condition 1 the horizontal component of the geomagnetic field was shifted by 90 degrees using a helmholtz coil. In condition 2 a high frequently oscillating field (1.156 MHz was applied in addition to the shifted field. Another group of birds was trained to solve the orientation task, but with visual landmarks as directional cue. The birds were then tested for their orientation performance in the same magnetic conditions as applied for the first experiment. Results The zebra finches could be trained successfully to orient in the geomagnetic field for food search in the north/south axis. They were also well oriented in test condition 1, with the magnetic field shifted horizontally by 90 degrees. In contrast, when the oscillating field was added, the directional choices during food search were randomly distributed. Birds that were trained to visually guided orientation showed no difference of orientation performance in the two magnetic conditions. Conclusion The results

  18. Brood size and immunity costs in zebra finches Taeniopygia guttata

    NARCIS (Netherlands)

    Verhulst, S; Riedstra, B; Wiersma, P

    Birds rearing experimentally enlarged broods have lower antibody responses to a novel antigen, and we tested three hypotheses that could explain this result. We used zebra finches Taeniopygia guttata inoculated with sheep red blood cells (SRBC) as a study system, for which this trade-off was

  19. Evaluation of Best Practices for the Euthanasia of Zebra Finches (Taeniopygia guttata).

    Science.gov (United States)

    Scott, Kathleen E; Bracchi, Lauren A; Lieberman, Mia T; Hill, Nichola J; Caron, Tyler J; Patterson, Mary M

    2017-11-01

    Although zebra finches (Taeniopygia guttata) have been used in biomedical research for many years, no published reports are available about euthanizing these small birds. In this study, we compared 5 methods for zebra finch euthanasia: sodium pentobarbital (NaP) given intracoelomically with physical restraint but no anesthesia; isoflurane anesthesia followed by intracoelomic injection of NaP; and CO2 asphyxiation at 20%, 40%, and 80% chamber displacement rates (percentage of chamber volume per minute). Birds undergoing euthanasia were videorecorded and scored by 2 observers for behaviors potentially related to discomfort or distress. Time to recumbency and time until respiratory arrest (RA) were also assessed. RA was achieved faster by using NaP in a conscious bird compared to using isoflurane anesthesia followed by NaP; however, neither method caused behaviors that might affect animal welfare, such as open-mouth breathing, to any appreciable extent. Among the CO2 treatment groups, there was an inverse correlation between the chamber displacement rate used and the duration of open-mouth breathing, onset of head retroflexion, and time to RA. The results demonstrate that the intracoelomic administration of NaP in an awake, restrained zebra finch is a rapid and effective method of euthanasia. If CO2 is used to euthanize these birds, a high displacement rate (for example, 80%) will minimize the duration of the procedure and associated behaviors.

  20. Maternal effects underlie ageing costs of growth in the zebra finch (Taeniopygia guttata.

    Directory of Open Access Journals (Sweden)

    Mathilde L Tissier

    Full Text Available Maternal effects provide a mechanism to adapt offspring phenotype and optimize the mother's fitness to current environmental conditions. Transferring steroids to the yolk is one way mothers can translate environmental information into potential adaptive signals for offspring. However, maternally-derived hormones might also have adverse effects for offspring. For example, recent data in zebra finch chicks suggested that ageing related-processes (i.e. oxidative stress and telomere loss were increased after egg-injection of corticosterone (CORT. Still, we have few experimental data describing the effect of maternal effects on the growth-ageing trade-off in offspring. Here, we chronically treated pre-laying zebra finch females (Taeniopygia guttata with 17-β-estradiol (E2 or CORT, and followed offspring growth and cellular ageing rates (oxidative stress and telomere loss. CORT treatment decreased growth rate in male chicks and increased rate of telomere loss in mothers and female offspring. E2 increased body mass gain in male offspring, while reducing oxidative stress in both sexes but without affecting telomere loss. Since shorter telomeres were previously found to be a proxy of individual lifespan in zebra finches, maternal effects may, through pleiotropic effects, be important determinants of offspring life-expectancy by modulating ageing rate during embryo and post-natal growth.

  1. Discovery of the First Germline-Restricted Gene by Subtractive Transcriptomic Analysis in the Zebra Finch, Taeniopygia guttata.

    Science.gov (United States)

    Biederman, Michelle K; Nelson, Megan M; Asalone, Kathryn C; Pedersen, Alyssa L; Saldanha, Colin J; Bracht, John R

    2018-05-21

    Developmentally programmed genome rearrangements are rare in vertebrates, but have been reported in scattered lineages including the bandicoot, hagfish, lamprey, and zebra finch (Taeniopygia guttata) [1]. In the finch, a well-studied animal model for neuroendocrinology and vocal learning [2], one such programmed genome rearrangement involves a germline-restricted chromosome, or GRC, which is found in germlines of both sexes but eliminated from mature sperm [3, 4]. Transmitted only through the oocyte, it displays uniparental female-driven inheritance, and early in embryonic development is apparently eliminated from all somatic tissue in both sexes [3, 4]. The GRC comprises the longest finch chromosome at over 120 million base pairs [3], and previously the only known GRC-derived sequence was repetitive and non-coding [5]. Because the zebra finch genome project was sourced from male muscle (somatic) tissue [6], the remaining genomic sequence and protein-coding content of the GRC remain unknown. Here we report the first protein-coding gene from the GRC: a member of the α-soluble N-ethylmaleimide sensitive fusion protein (NSF) attachment protein (α-SNAP) family hitherto missing from zebra finch gene annotations. In addition to the GRC-encoded α-SNAP, we find an additional paralogous α-SNAP residing in the somatic genome (a somatolog)-making the zebra finch the first example in which α-SNAP is not a single-copy gene. We show divergent, sex-biased expression for the paralogs and also that positive selection is detectable across the bird α-SNAP lineage, including the GRC-encoded α-SNAP. This study presents the identification and evolutionary characterization of the first protein-coding GRC gene in any organism. Copyright © 2018 Elsevier Ltd. All rights reserved.

  2. Castration modulates singing patterns and electrophysiological properties of RA projection neurons in adult male zebra finches

    Directory of Open Access Journals (Sweden)

    Songhua Wang

    2014-04-01

    Full Text Available Castration can change levels of plasma testosterone. Androgens such as testosterone play an important role in stabilizing birdsong. The robust nucleus of the arcopallium (RA is an important premotor nucleus critical for singing. In this study, we investigated the effect of castration on singing patterns and electrophysiological properties of projection neurons (PNs in the RA of adult male zebra finches. Adult male zebra finches were castrated and the changes in bird song assessed. We also recorded the electrophysiological changes from RA PNs using patch clamp recording. We found that the plasma levels of testosterone were significantly decreased, song syllable’s entropy was increased and the similarity of motif was decreased after castration. Spontaneous and evoked firing rates, membrane time constants, and membrane capacitance of RA PNs in the castration group were lower than those of the control and the sham groups. Afterhyperpolarization AHP time to peak of spontaneous action potential (AP was prolonged after castration.These findings suggest that castration decreases song stereotypy and excitability of RA PNs in male zebra finches.

  3. Mechanisms underlying speech sound discrimination and categorization in humans and zebra finches

    NARCIS (Netherlands)

    Burgering, Merel A.; ten Cate, Carel; Vroomen, Jean

    Speech sound categorization in birds seems in many ways comparable to that by humans, but it is unclear what mechanisms underlie such categorization. To examine this, we trained zebra finches and humans to discriminate two pairs of edited speech sounds that varied either along one dimension (vowel

  4. A daily oscillation in the fundamental frequency and amplitude of harmonic syllables of zebra finch song.

    Directory of Open Access Journals (Sweden)

    William E Wood

    Full Text Available Complex motor skills are more difficult to perform at certain points in the day (for example, shortly after waking, but the daily trajectory of motor-skill error is more difficult to predict. By undertaking a quantitative analysis of the fundamental frequency (FF and amplitude of hundreds of zebra finch syllables per animal per day, we find that zebra finch song follows a previously undescribed daily oscillation. The FF and amplitude of harmonic syllables rises across the morning, reaching a peak near mid-day, and then falls again in the late afternoon until sleep. This oscillation, although somewhat variable, is consistent across days and across animals and does not require serotonin, as animals with serotonergic lesions maintained daily oscillations. We hypothesize that this oscillation is driven by underlying physiological factors which could be shared with other taxa. Song production in zebra finches is a model system for studying complex learned behavior because of the ease of gathering comprehensive behavioral data and the tractability of the underlying neural circuitry. The daily oscillation that we describe promises to reveal new insights into how time of day affects the ability to accomplish a variety of complex learned motor skills.

  5. "Bird Song Metronomics": Isochronous Organization of Zebra Finch Song Rhythm.

    Science.gov (United States)

    Norton, Philipp; Scharff, Constance

    2016-01-01

    The human capacity for speech and vocal music depends on vocal imitation. Songbirds, in contrast to non-human primates, share this vocal production learning with humans. The process through which birds and humans learn many of their vocalizations as well as the underlying neural system exhibit a number of striking parallels and have been widely researched. In contrast, rhythm, a key feature of language, and music, has received surprisingly little attention in songbirds. Investigating temporal periodicity in bird song has the potential to inform the relationship between neural mechanisms and behavioral output and can also provide insight into the biology and evolution of musicality. Here we present a method to analyze birdsong for an underlying rhythmic regularity. Using the intervals from one note onset to the next as input, we found for each bird an isochronous sequence of time stamps, a "signal-derived pulse," or pulse(S), of which a subset aligned with all note onsets of the bird's song. Fourier analysis corroborated these results. To determine whether this finding was just a byproduct of the duration of notes and intervals typical for zebra finches but not dependent on the individual duration of elements and the sequence in which they are sung, we compared natural songs to models of artificial songs. Note onsets of natural song deviated from the pulse(S) significantly less than those of artificial songs with randomized note and gap durations. Thus, male zebra finch song has the regularity required for a listener to extract a perceived pulse (pulse(P)), as yet untested. Strikingly, in our study, pulses(S) that best fit note onsets often also coincided with the transitions between sub-note elements within complex notes, corresponding to neuromuscular gestures. Gesture durations often equaled one or more pulse(S) periods. This suggests that gesture duration constitutes the basic element of the temporal hierarchy of zebra finch song rhythm, an interesting parallel

  6. Using Digital Images of the Zebra Finch Song System as a Tool to Teach Organizational Effects of Steroid Hormones: A Free Downloadable Module

    Science.gov (United States)

    Grisham, William; Schottler, Natalie A.; Beck McCauley, Lisa M.; Pham, Anh P.; Ruiz, Maureen L.; Fong, Michelle C.; Cui, Xinran

    2011-01-01

    Zebra finch song behavior is sexually dimorphic: males sing and females do not. The neural system underlying this behavior is sexually dimorphic, and this sex difference is easy to quantify. During development, the zebra finch song system can be altered by steroid hormones, specifically estradiol, which actually masculinizes it. Because of the…

  7. Does foraging behaviour affect female mate preferences and pair formation in captive zebra finches?

    Directory of Open Access Journals (Sweden)

    Neeltje J Boogert

    Full Text Available BACKGROUND: Successful foraging is essential for survival and reproductive success. In many bird species, foraging is a learned behaviour. To cope with environmental change and survive periods in which regular foods are scarce, the ability to solve novel foraging problems by learning new foraging techniques can be crucial. Although females have been shown to prefer more efficient foragers, the effect of males' foraging techniques on female mate choice has never been studied. We tested whether females would prefer males showing the same learned foraging technique as they had been exposed to as juveniles, or whether females would prefer males that showed a complementary foraging technique. METHODOLOGY/PRINCIPAL FINDINGS: We first trained juvenile male and female zebra finches (Taeniopygia guttata to obtain a significant proportion of their food by one of two foraging techniques. We then tested whether females showed a preference for males with the same or the alternative technique. We found that neither a male's foraging technique nor his foraging performance affected the time females spent in his proximity in the mate-choice apparatus. We then released flocks of these finches into an aviary to investigate whether assortative pairing would be facilitated by birds taught the same technique exploiting the same habitat. Zebra finches trained as juveniles in a specific foraging technique maintained their foraging specialisation in the aviary as adults. However, pair formation and nest location were random with regard to foraging technique. CONCLUSIONS/SIGNIFICANCE: Our findings show that zebra finches can be successfully trained to be foraging specialists. However, the robust negative results of the conditions tested here suggest that learned foraging specializations do not affect mate choice or pair formation in our experimental context.

  8. Altered auditory BOLD response to conspecific birdsong in zebra finches with stuttered syllables.

    Directory of Open Access Journals (Sweden)

    Henning U Voss

    2010-12-01

    Full Text Available How well a songbird learns a song appears to depend on the formation of a robust auditory template of its tutor's song. Using functional magnetic resonance neuroimaging we examine auditory responses in two groups of zebra finches that differ in the type of song they sing after being tutored by birds producing stuttering-like syllable repetitions in their songs. We find that birds that learn to produce the stuttered syntax show attenuated blood oxygenation level-dependent (BOLD responses to tutor's song, and more pronounced responses to conspecific song primarily in the auditory area field L of the avian forebrain, when compared to birds that produce normal song. These findings are consistent with the presence of a sensory song template critical for song learning in auditory areas of the zebra finch forebrain. In addition, they suggest a relationship between an altered response related to familiarity and/or saliency of song stimuli and the production of variant songs with stuttered syllables.

  9. “Bird Song Metronomics”: Isochronous Organization of Zebra Finch Song Rhythm

    Science.gov (United States)

    Norton, Philipp; Scharff, Constance

    2016-01-01

    The human capacity for speech and vocal music depends on vocal imitation. Songbirds, in contrast to non-human primates, share this vocal production learning with humans. The process through which birds and humans learn many of their vocalizations as well as the underlying neural system exhibit a number of striking parallels and have been widely researched. In contrast, rhythm, a key feature of language, and music, has received surprisingly little attention in songbirds. Investigating temporal periodicity in bird song has the potential to inform the relationship between neural mechanisms and behavioral output and can also provide insight into the biology and evolution of musicality. Here we present a method to analyze birdsong for an underlying rhythmic regularity. Using the intervals from one note onset to the next as input, we found for each bird an isochronous sequence of time stamps, a “signal-derived pulse,” or pulseS, of which a subset aligned with all note onsets of the bird's song. Fourier analysis corroborated these results. To determine whether this finding was just a byproduct of the duration of notes and intervals typical for zebra finches but not dependent on the individual duration of elements and the sequence in which they are sung, we compared natural songs to models of artificial songs. Note onsets of natural song deviated from the pulseS significantly less than those of artificial songs with randomized note and gap durations. Thus, male zebra finch song has the regularity required for a listener to extract a perceived pulse (pulseP), as yet untested. Strikingly, in our study, pulsesS that best fit note onsets often also coincided with the transitions between sub-note elements within complex notes, corresponding to neuromuscular gestures. Gesture durations often equaled one or more pulseS periods. This suggests that gesture duration constitutes the basic element of the temporal hierarchy of zebra finch song rhythm, an interesting parallel to the

  10. A three-dimensional MRI atlas of the zebra finch brain in stereotaxic coordinates

    DEFF Research Database (Denmark)

    Poirier, Colline; Vellema, Michiel; Verhoye, Marleen

    2008-01-01

    of different brain areas (nuclei) involved in the sensory and motor control of song. Until now, the only published atlases of songbird brains consisted in drawings based on histological slices of the canary and of the zebra finch brain. Taking advantage of high-magnetic field (7 Tesla) MRI technique, we...

  11. Sex-specific effects of yolk testosterone on survival, begging and growth of zebra finches

    NARCIS (Netherlands)

    von Engelhardt, N; Carere, C; Dijkstra, C; Groothuis, TGG

    2006-01-01

    Yolk androgens affect offspring hatching, begging, growth and survival in many bird species. If these effects are sex-specific, yolk androgen deposition may constitute a mechanism for differential investment in male and female offspring. We tested this hypothesis in zebra finches. In this species,

  12. Bill redness is positively associated with reproduction and survival in male and female zebra finches.

    Directory of Open Access Journals (Sweden)

    Mirre J P Simons

    Full Text Available Sexual traits can serve as honest indicators of phenotypic quality when they are costly. Brightly coloured yellow to red traits, which are pigmented by carotenoids, are relatively common in birds, and feature in sexual selection. Carotenoids have been linked to immune and antioxidant function, and the trade-off between ornamentation and these physiological functions provides a potential mechanism rendering carotenoid based signals costly. Mutual ornamentation is also common in birds and can be maintained by mutual mate choice for this ornament or by a correlated response in one sex to selection on the other sex. When selection pressures differ between the sexes this can cause intralocus sexual conflict. Sexually antagonistic selection pressures have been demonstrated for few sexual traits, and for carotenoid-dependent traits there is a single example: bill redness was found to be positively associated with survival and reproductive output in male zebra finches, but negatively so in females. We retested these associations in our captive zebra finch population without two possible limitations of this earlier study. Contrary to the earlier findings, we found no evidence for sexually antagonistic selection. In both sexes, individuals with redder bills showed higher survival. This association disappeared among the females with the reddest bills. Furthermore, females with redder bills achieved higher reproductive output. We conclude that bill redness of male and female zebra finches honestly signals phenotypic quality, and discuss the possible causes of the differences between our results and earlier findings.

  13. Bird brains and songs : Neural mechanisms of auditory memory and perception in zebra finches

    NARCIS (Netherlands)

    Gobes, S.M.H.|info:eu-repo/dai/nl/304832669

    2009-01-01

    Songbirds, such as zebra finches, learn their songs from a ‘tutor’ (usually the father), early in life. There are strong parallels between the behavioural, cognitive and neural processes that underlie vocal learning in humans and songbirds. In both cases there is a sensitive period for auditory

  14. Familial differences in the effects of mercury on reproduction in zebra finches

    International Nuclear Information System (INIS)

    Varian-Ramos, Claire W.; Swaddle, John P.; Cristol, Daniel A.

    2013-01-01

    Ecotoxicologists often implicitly assume that populations are homogenous entities in which all individuals have similar responses to a contaminant. However, genetically variable responses occur within populations. This variation can be visualized using dose–response curves of genetically related groups, similar to the way that evolutionary biologists construct reaction norms. We assessed the variation in reproductive success of full-sibling families of captive zebra finches (Taeniopygia guttata) experimentally exposed to methylmercury. We found significant variation among families in the effects of methylmercury on several reproductive parameters. This variation suggests that there may be strong responses to selection for resistant genotypes in contaminated areas. This has important implications for the evolution of tolerance as well as risk assessment and wildlife conservation efforts on sites with legacy contamination. -- Highlights: •Dose-response curves can visualize genetic differences in response to pollutants. •Families of zebra finch respond differently to mercury contamination. •Differences in reproductive success can lead to selection for resistant genotypes. •Resistance to contamination has implications for risk assessment and conservation. -- Genetic variation in response to contaminants can lead to adaptation on long-term contaminated sites, with implications for risk assessment and conservation of impacted populations

  15. Cannabinoid exposure during zebra finch sensorimotor vocal learning persistently alters expression of endocannabinoid signaling elements and acute agonist responsiveness

    Directory of Open Access Journals (Sweden)

    Lichtman Aron H

    2011-01-01

    Full Text Available Abstract Background Previously we have found that cannabinoid treatment of zebra finches during sensorimotor stages of vocal development alters song patterns produced in adulthood. Such persistently altered behavior must be attributable to changes in physiological substrates responsible for song. We are currently working to identify the nature of such physiological changes, and to understand how they contribute to altered vocal learning. One possibility is that developmental agonist exposure results in altered expression of elements of endocannabinoid signaling systems. To test this hypothesis we have studied effects of the potent cannabinoid receptor agonist WIN55212-2 (WIN on endocannabinoid levels and densities of CB1 immunostaining in zebra finch brain. Results We found that late postnatal WIN treatment caused a long-term global disregulation of both levels of the endocannabinoid, 2-arachidonyl glycerol (2-AG and densities of CB1 immunostaining across brain regions, while repeated cannabinoid treatment in adults produced few long-term changes in the endogenous cannabinoid system. Conclusions Our findings indicate that the zebra finch endocannabinoid system is particularly sensitive to exogenous agonist exposure during the critical period of song learning and provide insight into susceptible brain areas.

  16. Is the rate of metabolic ageing and survival determined by Basal metabolic rate in the zebra finch?

    Directory of Open Access Journals (Sweden)

    Bernt Rønning

    Full Text Available The relationship between energy metabolism and ageing is of great interest because aerobic metabolism is the primary source of reactive oxygen species which is believed to be of major importance in the ageing process. We conducted a longitudinal study on captive zebra finches where we tested the effect of age on basal metabolic rate (BMR, as well as the effect of BMR on the rate of metabolic ageing (decline in BMR with age and survival. Basal metabolic rate declined with age in both sexes after controlling for the effect of body mass, indicating a loss of functionality with age. This loss of functionality could be due to accumulated oxidative damage, believed to increase with increasing metabolic rate, c.f. the free radical theory of ageing. If so, we would expect the rate of metabolic ageing to increase and survival to decrease with increasing BMR. However, we found no effect of BMR on the rate of metabolic ageing. Furthermore, survival was not affected by BMR in the males. In female zebra finches there was a tendency for survival to decrease with increasing BMR, but the effect did not reach significance (P<0.1. Thus, the effect of BMR on the rate of functional deterioration with age, if any, was not strong enough to influence neither the rate of metabolic ageing nor survival in the zebra finches.

  17. Is the rate of metabolic ageing and survival determined by Basal metabolic rate in the zebra finch?

    Science.gov (United States)

    Rønning, Bernt; Moe, Børge; Berntsen, Henrik H; Noreen, Elin; Bech, Claus

    2014-01-01

    The relationship between energy metabolism and ageing is of great interest because aerobic metabolism is the primary source of reactive oxygen species which is believed to be of major importance in the ageing process. We conducted a longitudinal study on captive zebra finches where we tested the effect of age on basal metabolic rate (BMR), as well as the effect of BMR on the rate of metabolic ageing (decline in BMR with age) and survival. Basal metabolic rate declined with age in both sexes after controlling for the effect of body mass, indicating a loss of functionality with age. This loss of functionality could be due to accumulated oxidative damage, believed to increase with increasing metabolic rate, c.f. the free radical theory of ageing. If so, we would expect the rate of metabolic ageing to increase and survival to decrease with increasing BMR. However, we found no effect of BMR on the rate of metabolic ageing. Furthermore, survival was not affected by BMR in the males. In female zebra finches there was a tendency for survival to decrease with increasing BMR, but the effect did not reach significance (PBMR on the rate of functional deterioration with age, if any, was not strong enough to influence neither the rate of metabolic ageing nor survival in the zebra finches.

  18. Drinking songs: alcohol effects on learned song of zebra finches.

    Directory of Open Access Journals (Sweden)

    Christopher R Olson

    Full Text Available Speech impairment is one of the most intriguing and least understood effects of alcohol on cognitive function, largely due to the lack of data on alcohol effects on vocalizations in the context of an appropriate experimental model organism. Zebra finches, a representative songbird and a premier model for understanding the neurobiology of vocal production and learning, learn song in a manner analogous to how humans learn speech. Here we show that when allowed access, finches readily drink alcohol, increase their blood ethanol concentrations (BEC significantly, and sing a song with altered acoustic structure. The most pronounced effects were decreased amplitude and increased entropy, the latter likely reflecting a disruption in the birds' ability to maintain the spectral structure of song under alcohol. Furthermore, specific syllables, which have distinct acoustic structures, were differentially influenced by alcohol, likely reflecting a diversity in the neural mechanisms required for their production. Remarkably, these effects on vocalizations occurred without overt effects on general behavioral measures, and importantly, they occurred within a range of BEC that can be considered risky for humans. Our results suggest that the variable effects of alcohol on finch song reflect differential alcohol sensitivity of the brain circuitry elements that control different aspects of song production. They also point to finches as an informative model for understanding how alcohol affects the neuronal circuits that control the production of learned motor behaviors.

  19. FoxP2 isoforms delineate spatiotemporal transcriptional networks for vocal learning in the zebra finch

    Science.gov (United States)

    Day, Nancy F; Kimball, Todd Haswell; Aamodt, Caitlin M; Heston, Jonathan B; Hilliard, Austin T; Xiao, Xinshu; White, Stephanie A

    2018-01-01

    Human speech is one of the few examples of vocal learning among mammals yet ~half of avian species exhibit this ability. Its neurogenetic basis is largely unknown beyond a shared requirement for FoxP2 in both humans and zebra finches. We manipulated FoxP2 isoforms in Area X, a song-specific region of the avian striatopallidum analogous to human anterior striatum, during a critical period for song development. We delineate, for the first time, unique contributions of each isoform to vocal learning. Weighted gene coexpression network analysis of RNA-seq data revealed gene modules correlated to singing, learning, or vocal variability. Coexpression related to singing was found in juvenile and adult Area X whereas coexpression correlated to learning was unique to juveniles. The confluence of learning and singing coexpression in juvenile Area X may underscore molecular processes that drive vocal learning in young zebra finches and, by analogy, humans. PMID:29360038

  20. Developmental exposure to a brominated flame retardant: An assessment of effects on physiology, growth, and reproduction in a songbird, the zebra finch

    International Nuclear Information System (INIS)

    Eng, Margaret L.; Williams, Tony D.; Elliott, John E.

    2013-01-01

    Mixtures of polybrominated diphenyl ethers (PBDEs) have been widely used as additive flame retardants, and BDE-99 is one of the most predominant congeners found in the environment. BDE-99 has been reported in avian samples worldwide, yet knowledge of its toxicity to birds is minimal. We assessed the short- and long-term effects of nestling exposure to environmentally relevant levels of BDE-99 in a model passerine, the zebra finch. Early exposure to BDE-99 did not affect hematocrit, oxidative stress, or thyroid hormones in either the juvenile or adult stages, and there were no effects on chick growth or survival. BDE-99 exposure caused a dose-dependent delay in timing of reproduction, but there were no other effects on reproductive success. In zebra finches, endpoints related to reproductive behavior appear to be the most sensitive to BDE-99. However, passerines overall appear to be less sensitive than birds of prey or mammals to PBDE exposure. -- Highlights: •We exposed zebra finches nestlings to BDE-99 and raised them to sexual maturity. •Found no effects on physiology, chick growth, survival, or reproductive success. •As BDE-99 dose increased, laying interval increased. •Passerine birds possibly less sensitive to BDE-99 than mammals or other bird species. -- Nestling exposure to BDE-99 affects timing of breeding in zebra finches, but overall passerines appear to be less sensitive to PBDEs than mammals or other bird species

  1. Digital atlas of the zebra finch (Taeniopygia guttata) brain: a high-resolution photo atlas.

    Science.gov (United States)

    Karten, Harvey J; Brzozowska-Prechtl, Agnieszka; Lovell, Peter V; Tang, Daniel D; Mello, Claudio V; Wang, Haibin; Mitra, Partha P

    2013-11-01

    We describe a set of new comprehensive, high-quality, high-resolution digital images of histological sections from the brain of male zebra finches (Taeniopygia guttata) and make them publicly available through an interactive website (http://zebrafinch.brainarchitecture.org/). These images provide a basis for the production of a dimensionally accurate and detailed digital nonstereotaxic atlas. Nissl- and myelin-stained brain sections are provided in the transverse, sagittal, and horizontal planes, with the transverse plane approximating the more traditional Frankfurt plane. In addition, a separate set of brain sections in this same plane is stained for tyrosine hydroxylase, revealing the distribution of catecholaminergic neurons (dopaminergic, noradrenergic, and adrenergic) in the songbird brain. For a subset of sagittal sections we also prepared a corresponding set of drawings, defining and annotating various nuclei, fields, and fiber tracts that are visible under Nissl and myelin staining. This atlas of the zebra finch brain is expected to become an important tool for birdsong research and comparative studies of brain organization and evolution. Copyright © 2013 Wiley Periodicals, Inc.

  2. Chick Development and Asynchroneous Hatching in the Zebra Finch (Taeniopygia guttata castanotis).

    Science.gov (United States)

    Ikebuchi, Maki; Okanoya, Kazuo; Hasegawa, Toshikazu; Bischof, Hans-Joachim

    2017-10-01

    The mode of hatching in birds has important impacts on both parents and chicks, including the costs and risks of breeding for parents, and sibling competition in a clutch. Birds with multiple eggs in a single clutch often begin incubating when most eggs are laid, thereby reducing time of incubation, nursing burden, and sibling competition. In some songbirds and some other species, however, incubation starts immediately after the first egg is laid, and the chicks thus hatch asynchronously. This may result in differences in parental care and in sibling competition based on body size differences among older and younger chicks, which in turn might produce asynchronous development among siblings favoring the first hatchling, and further affect the development and fitness of the chicks after fledging. To determine whether such processes in fact occur in the zebra finch, we observed chick development in 18 clutches of zebra finches. We found that there were effects of asynchronous hatching, but these were smaller than expected and mostly not significant. Our observations suggest that the amount of care given to each chick may be equated with such factors as a camouflage effect of the down feathers, and that the low illumination within the nest also complicates the determination of the hatching order by the parents.

  3. Mate call as reward: Acoustic communication signals can acquire positive reinforcing values during adulthood in female zebra finches (Taeniopygia guttata).

    Science.gov (United States)

    Hernandez, Alexandra M; Perez, Emilie C; Mulard, Hervé; Mathevon, Nicolas; Vignal, Clémentine

    2016-02-01

    Social stimuli can have rewarding properties and promote learning. In birds, conspecific vocalizations like song can act as a reinforcer, and specific song variants can acquire particular rewarding values during early life exposure. Here we ask if, during adulthood, an acoustic signal simpler and shorter than song can become a reward for a female songbird because of its particular social value. Using an operant choice apparatus, we showed that female zebra finches display a preferential response toward their mate's calls. This reinforcing value of mate's calls could be involved in the maintenance of the monogamous pair-bond of the zebra finch. (c) 2016 APA, all rights reserved).

  4. Costs of reproduction in the Zebra Finch Taeniopygia guttata : Manipulation of brood size in the laboratory

    NARCIS (Netherlands)

    deKogel, CH; Overkamp, GFJ

    1996-01-01

    Brood size of Zebra Finches Taeniopygia guttata was manipulated in an attempt to identify a trade-off between current and subsequent reproduction in a laboratory situation with ad libitum food availability. The birds were able to raise a larger brood than the most frequent brood size under the same

  5. Sex-dependent effects of nutrition on telomere dynamics in zebra finches (Taeniopygia guttata)

    OpenAIRE

    Noguera, Jose C.; Metcalfe, Neil B.; Boner, Winnie; Monaghan, Pat

    2015-01-01

    At a cellular level, oxidative stress is known to increase telomere attrition, and hence cellular senescence and risk of disease. It has been proposed that dietary micronutrients play an important role in telomere protection due to their antioxidant properties. We experimentally manipulated dietary micronutrients during early life in zebra finches (Taeniopygia guttata). We found no effects of micronutrient intake on telomere loss during chick growth. However, females given a diet high in micr...

  6. Exploring sex differences in the adult zebra finch brain: In vivo diffusion tensor imaging and ex vivo super-resolution track density imaging.

    Science.gov (United States)

    Hamaide, Julie; De Groof, Geert; Van Steenkiste, Gwendolyn; Jeurissen, Ben; Van Audekerke, Johan; Naeyaert, Maarten; Van Ruijssevelt, Lisbeth; Cornil, Charlotte; Sijbers, Jan; Verhoye, Marleen; Van der Linden, Annemie

    2017-02-01

    Zebra finches are an excellent model to study the process of vocal learning, a complex socially-learned tool of communication that forms the basis of spoken human language. So far, structural investigation of the zebra finch brain has been performed ex vivo using invasive methods such as histology. These methods are highly specific, however, they strongly interfere with performing whole-brain analyses and exclude longitudinal studies aimed at establishing causal correlations between neuroplastic events and specific behavioral performances. Therefore, the aim of the current study was to implement an in vivo Diffusion Tensor Imaging (DTI) protocol sensitive enough to detect structural sex differences in the adult zebra finch brain. Voxel-wise comparison of male and female DTI parameter maps shows clear differences in several components of the song control system (i.e. Area X surroundings, the high vocal center (HVC) and the lateral magnocellular nucleus of the anterior nidopallium (LMAN)), which corroborate previous findings and are in line with the clear behavioral difference as only males sing. Furthermore, to obtain additional insights into the 3-dimensional organization of the zebra finch brain and clarify findings obtained by the in vivo study, ex vivo DTI data of the male and female brain were acquired as well, using a recently established super-resolution reconstruction (SRR) imaging strategy. Interestingly, the SRR-DTI approach led to a marked reduction in acquisition time without interfering with the (spatial and angular) resolution and SNR which enabled to acquire a data set characterized by a 78μm isotropic resolution including 90 diffusion gradient directions within 44h of scanning time. Based on the reconstructed SRR-DTI maps, whole brain probabilistic Track Density Imaging (TDI) was performed for the purpose of super resolved track density imaging, further pushing the resolution up to 40μm isotropic. The DTI and TDI maps realized atlas

  7. Song exposure regulates known and novel microRNAs in the zebra finch auditory forebrain

    Directory of Open Access Journals (Sweden)

    Kim Jong H

    2011-05-01

    Full Text Available Abstract Background In an important model for neuroscience, songbirds learn to discriminate songs they hear during tape-recorded playbacks, as demonstrated by song-specific habituation of both behavioral and neurogenomic responses in the auditory forebrain. We hypothesized that microRNAs (miRNAs or miRs may participate in the changing pattern of gene expression induced by song exposure. To test this, we used massively parallel Illumina sequencing to analyse small RNAs from auditory forebrain of adult zebra finches exposed to tape-recorded birdsong or silence. Results In the auditory forebrain, we identified 121 known miRNAs conserved in other vertebrates. We also identified 34 novel miRNAs that do not align to human or chicken genomes. Five conserved miRNAs showed significant and consistent changes in copy number after song exposure across three biological replications of the song-silence comparison, with two increasing (tgu-miR-25, tgu-miR-192 and three decreasing (tgu-miR-92, tgu-miR-124, tgu-miR-129-5p. We also detected a locus on the Z sex chromosome that produces three different novel miRNAs, with supporting evidence from Northern blot and TaqMan qPCR assays for differential expression in males and females and in response to song playbacks. One of these, tgu-miR-2954-3p, is predicted (by TargetScan to regulate eight song-responsive mRNAs that all have functions in cellular proliferation and neuronal differentiation. Conclusions The experience of hearing another bird singing alters the profile of miRNAs in the auditory forebrain of zebra finches. The response involves both known conserved miRNAs and novel miRNAs described so far only in the zebra finch, including a novel sex-linked, song-responsive miRNA. These results indicate that miRNAs are likely to contribute to the unique behavioural biology of learned song communication in songbirds.

  8. Housing conditions and sacrifice protocol affect neural activity and vocal behavior in a songbird species, the zebra finch (Taeniopygia guttata).

    Science.gov (United States)

    Elie, Julie Estelle; Soula, Hédi Antoine; Trouvé, Colette; Mathevon, Nicolas; Vignal, Clémentine

    2015-12-01

    Individual cages represent a widely used housing condition in laboratories. This isolation represents an impoverished physical and social environment in gregarious animals. It prevents animals from socializing, even when auditory and visual contact is maintained. Zebra finches are colonial songbirds that are widely used as laboratory animals for the study of vocal communication from brain to behavior. In this study, we investigated the effect of single housing on the vocal behavior and the brain activity of male zebra finches (Taeniopygia guttata): male birds housed in individual cages were compared to freely interacting male birds housed as a social group in a communal cage. We focused on the activity of septo-hypothalamic regions of the "social behavior network" (SBN), a set of limbic regions involved in several social behaviors in vertebrates. The activity of four structures of the SBN (BSTm, medial bed nucleus of the stria terminalis; POM, medial preoptic area; lateral septum; ventromedial hypothalamus) and one associated region (paraventricular nucleus of the hypothalamus) was assessed using immunoreactive nuclei density of the immediate early gene Zenk (egr-1). We further assessed the identity of active cell populations by labeling vasotocin (VT). Brain activity was related to behavioral activities of birds like physical and vocal interactions. We showed that individual housing modifies vocal exchanges between birds compared to communal housing. This is of particular importance in the zebra finch, a model species for the study of vocal communication. In addition, a protocol that daily removes one or two birds from the group affects differently male zebra finches depending of their housing conditions: while communally-housed males changed their vocal output, brains of individually housed males show increased Zenk labeling in non-VT cells of the BSTm and enhanced correlation of Zenk-revealed activity between the studied structures. These results show that

  9. Zebra finches can use positional and transitional cues to distinguish vocal element strings.

    Science.gov (United States)

    Chen, Jiani; Ten Cate, Carel

    2015-08-01

    Learning sequences is of great importance to humans and non-human animals. Many motor and mental actions, such as singing in birds and speech processing in humans, rely on sequential learning. At least two mechanisms are considered to be involved in such learning. The chaining theory proposes that learning of sequences relies on memorizing the transitions between adjacent items, while the positional theory suggests that learners encode the items according to their ordinal position in the sequence. Positional learning is assumed to dominate sequential learning. However, human infants exposed to a string of speech sounds can learn transitional (chaining) cues. So far, it is not clear whether birds, an increasingly important model for examining vocal processing, can do this. In this study we use a Go-Nogo design to examine whether zebra finches can use transitional cues to distinguish artificially constructed strings of song elements. Zebra finches were trained with sequences differing in transitional and positional information and next tested with novel strings sharing positional and transitional similarities with the training strings. The results show that they can attend to both transitional and positional cues and that their sequential coding strategies can be biased toward transitional cues depending on the learning context. This article is part of a Special Issue entitled: In Honor of Jerry Hogan. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. Estradiol and song affect female zebra finch behavior independent of dopamine in the striatum

    OpenAIRE

    Svec, Lace A.; Lookingland, Keith J.; Wade, Juli

    2009-01-01

    Female songbirds display preferences for certain song characteristics, but the neural and hormonal mechanisms mediating these preferences are not fully clear. The present study sought to further explore the role of estradiol, as well as assess potential roles of dopaminergic systems, on behavioral responses to song. Adult female zebra finches were treated with estradiol and exposed to tutored or untutored song or silence. Behavior was quantified and neurochemistry of the nucleus accumbens and...

  11. Exposure to dietary mercury alters cognition and behavior of zebra finches.

    Science.gov (United States)

    Swaddle, John P; Diehl, Tessa R; Taylor, Capwell E; Fanaee, Aaron S; Benson, Jessica L; Huckstep, Neil R; Cristol, Daniel A

    2017-04-01

    Environmental stressors can negatively affect avian cognitive abilities, potentially reducing fitness, for example by altering response to predators, display to mates, or memory of locations of food. We expand on current knowledge by investigating the effects of dietary mercury, a ubiquitous environmental pollutant and known neurotoxin, on avian cognition. Zebra finches Taeniopygia guttata were dosed for their entire lives with sub-lethal levels of mercury, at the environmentally relevant dose of 1.2 parts per million. In our first study, we compared the dosed birds with controls of the same age using tests of three cognitive abilities: spatial memory, inhibitory control, and color association. In the spatial memory assay, birds were tested on their ability to learn and remember the location of hidden food in their cage. The inhibitory control assay measured their ability to ignore visible but inaccessible food in favor of a learned behavior that provided the same reward. Finally, the color association task tested each bird's ability to associate a specific color with the presence of hidden food. Dietary mercury negatively affected spatial memory ability but not inhibitory control or color association. Our second study focused on three behavioral assays not tied to a specific skill or problem-solving: activity level, neophobia, and social dominance. Zebra finches exposed to dietary mercury throughout their lives were subordinate to, and more active than, control birds. We found no evidence that mercury exposure influenced our metric of neophobia. Together, these results suggest that sub-lethal exposure to environmental mercury selectively harms neurological pathways that control different cognitive abilities, with complex effects on behavior and fitness.

  12. The songbird syrinx morphome: a three-dimensional, high-resolution, interactive morphological map of the zebra finch vocal organ

    DEFF Research Database (Denmark)

    During, D. N.; Ziegler, A.; Thompson, C. K.

    2013-01-01

    in unprecedented detail. We provide interactive three-dimensional models that greatly improve the communication of complex morphological data and our understanding of syringeal function in general. Conclusions: Our results show that the syringeal skeleton is optimized for low weight driven by physiological...... and stimulation experiments. We also demonstrate how the syrinx can be stabilized during song to reduce mechanical noise and, as such, enhance repetitive execution of stereotypic motor patterns. In addition, we identify a cartilaginous structure suited to play a crucial role in the uncoupling of sound frequency...

  13. Sexual imprinting on continuous variation: do female zebra finches prefer or avoid unfamiliar sons of their foster parents?

    Science.gov (United States)

    Schielzeth, H; Burger, C; Bolund, E; Forstmeier, W

    2008-09-01

    Sexual imprinting on discrete variation that serves the identification of species, morphs or sexes is well documented. By contrast, sexual imprinting on continuous variation leading to individual differences in mating preferences within a single species, morph and sex has been studied only once (in humans). We measured female preferences in a captive population of wild-type zebra finches. Individual cross-fostering ensured that all subjects grew up with unrelated foster parents and nest mates. Females from two cohorts (N = 113) were given a simultaneous choice between (two or four) unfamiliar males, one of which was a genetic son of their foster parents (SFP). We found no significant overall preference for the SFP (combined effect size d = 0.14 +/- 0.15). Additionally, we tested if foster parent traits could potentially explain between-female variation in preferences. However, neither the effectiveness of cooperation between the parents nor male contribution to parental care affected female preferences for the son of the foster father. We conclude that at least in zebra finches sexual imprinting is not a major source of between-individual variation in mating preferences.

  14. Autoradiographic localization of nicotinic acetylcholine receptors in the brain of the zebra finch (Poephila guttata)

    International Nuclear Information System (INIS)

    Watson, J.T.; Adkins-Regan, E.; Whiting, P.; Lindstrom, J.M.; Podleski, T.R.

    1988-01-01

    We have localized nicotinic acetylcholine receptors in the zebra finch brain by using three 125I-labelled ligands: alpha bungarotoxin and two monoclonal antibodies to neuronal nicotinic receptors. Unfixed brains from intact adult male and female zebra finches were prepared for in vitro autoradiography. Low-resolution film autoradiograms and high-resolution emulsion autoradiograms were prepared for each of the three ligands. The major brain structures that bind all three of the ligands are hippocampus; hyperstriatum dorsalis; hyperstriatum ventralis; nucleus lentiformis mesencephali; nucleus pretectalis, some layers of the optic tectum; nucleus mesencephalicus lateralis; pars dorsalis; locus ceruleus; and all cranial motor nuclei except nucleus nervi hypoglossi. The major structures labelled only by [125I]-alpha bungarotoxin binding included hyperstriatum accessorium and the nuclei: preopticus medialis, medialis hypothalami posterioris, semilunaris, olivarius inferior, and the periventricular organ. Of the song control nuclei, nucleus magnocellularis of the anterior neostriatum; hyperstriatum ventralis, pars caudalis; nucleus intercollicularis; and nucleus hypoglossus were labelled. The binding patterns of the two antibodies were similar to one another but not identical. Both labelled nucleus spiriformis lateralis and nucleus geniculatus lateralis, pars ventralis especially heavily and also labelled the nucleus habenula medialis; nucleus subpretectalis; nucleus isthmi, pars magnocellularis; nucleus reticularis gigantocellularis; nucleus reticularis lateralis; nucleus tractus solitarii; nucleus vestibularis dorsolateralis; nucleus vestibularis lateralis; nucleus descendens nervi trigemini; and the deep cerebellar nuclei

  15. Social interaction with a tutor modulates responsiveness of specific auditory neurons in juvenile zebra finches.

    Science.gov (United States)

    Yanagihara, Shin; Yazaki-Sugiyama, Yoko

    2018-04-12

    Behavioral states of animals, such as observing the behavior of a conspecific, modify signal perception and/or sensations that influence state-dependent higher cognitive behavior, such as learning. Recent studies have shown that neuronal responsiveness to sensory signals is modified when animals are engaged in social interactions with others or in locomotor activities. However, how these changes produce state-dependent differences in higher cognitive function is still largely unknown. Zebra finches, which have served as the premier songbird model, learn to sing from early auditory experiences with tutors. They also learn from playback of recorded songs however, learning can be greatly improved when song models are provided through social communication with tutors (Eales, 1989; Chen et al., 2016). Recently we found a subset of neurons in the higher-level auditory cortex of juvenile zebra finches that exhibit highly selective auditory responses to the tutor song after song learning, suggesting an auditory memory trace of the tutor song (Yanagihara and Yazaki-Sugiyama, 2016). Here we show that auditory responses of these selective neurons became greater when juveniles were paired with their tutors, while responses of non-selective neurons did not change. These results suggest that social interaction modulates cortical activity and might function in state-dependent song learning. Copyright © 2018 Elsevier B.V. All rights reserved.

  16. Vasodilatory effects of exogenous nitric oxide on the brood patch of the Zebra finch (Taeniopygia guttata)

    OpenAIRE

    Södergren, Anna

    2010-01-01

    In birds like the Zebra finch (Taeniopygia guttata) the female, but not the male develop a brood patch upon incubation of eggs. The brood patch functions to increase heat exchange between the bird and the eggs. Development of the brood patch includes de-feathering, increased vascularization and edema formation. The increased vascularization is due to the development of arteriovenous anastomoses, AVA. The AVA are thermoregulatory vessels involved in cold induced vasodilation, CIVD, demonstrate...

  17. Implications of nutritional stress as nestling or fledgling on subsequent attractiveness and fecundity in zebra finches (Taeniopygia guttata)

    OpenAIRE

    Mariam Honarmand; E. Tobias Krause; Marc Naguib

    2017-01-01

    The conditions an organism experiences during early development can have profound and long lasting effects on its subsequent behavior, attractiveness, and life history decisions. Most previous studies have exposed individuals to different conditions throughout development until nutritional independence. Yet under natural conditions, individuals may experience limitations for much shorter periods due to transient environmental fluctuations. Here, we used zebra finches (Taeniopygia guttata) in ...

  18. Muscle activation patterns and motor anatomy of Anna's hummingbirds Calypte anna and zebra finches Taeniopygia guttata.

    Science.gov (United States)

    Donovan, Edward R; Keeney, Brooke K; Kung, Eric; Makan, Sirish; Wild, J Martin; Altshuler, Douglas L

    2013-01-01

    Flying animals exhibit profound transformations in anatomy, physiology, and neural architecture. Although much is known about adaptations in the avian skeleton and musculature, less is known about neuroanatomy and motor unit integration for bird flight. Hummingbirds are among the most maneuverable and specialized of vertebrate fliers, and two unusual neuromuscular features have been previously reported: (1) the pectoralis major has a unique distribution pattern of motor end plates (MEPs) compared with all other birds and (2) electromyograms (EMGs) from the hummingbird's pectoral muscles, the pectoralis major and the supracoracoideus, show activation bursts composed of one or a few spikes that appear to have a very consistent pattern. Here, we place these findings in a broader context by comparing the MEPs, EMGs, and organization of the spinal motor neuron pools of flight muscles of Anna's hummingbird Calypte anna, zebra finches Taeniopygia guttata, and, for MEPs, several other species. The previously shown MEP pattern of the hummingbird pectoralis major is not shared with its closest taxonomic relative, the swift, and appears to be unique to hummingbirds. MEP arrangements in previously undocumented wing muscles show patterns that differ somewhat from other avian muscles. In the parallel-fibered strap muscles of the shoulder, MEP patterns appear to relate to muscle length, with the smallest muscles having fibers that span the entire muscle. MEP patterns in pennate distal wing muscles were the same regardless of size, with tightly clustered bands in the middle portion of the muscle, not evenly distributed bands over the muscle's entire length. Muscle activations were examined during slow forward flight in both species, during hovering in hummingbirds, and during slow ascents in zebra finches. The EMG bursts of a wing muscle, the pronator superficialis, were highly variable in peak number, size, and distribution across wingbeats for both species. In the pectoralis

  19. Sexual dimorphism in song-induced ZENK expression in the medial striatum of juvenile zebra finches

    OpenAIRE

    Bailey, David J.; Wade, Juli

    2006-01-01

    In the brains of male zebra finches (Taeniopygia guttata), the nuclei that direct song learning and production are larger than the corresponding regions in females, who do not sing. The dimorphism in Area X of the medial striatum (MSt), an area important for song learning, is even more dramatic in that it is identifiable in males but not females by Nissl stain. In the present study, conspecific song, but not other auditory stimuli, induced expression of the immediate early gene ZENK in the MS...

  20. Dopamine physiology in the basal ganglia of male zebra finches during social stimulation.

    Science.gov (United States)

    Ihle, Eva C; van der Hart, Marieke; Jongsma, Minke; Tecott, Larry H; Doupe, Allison J

    2015-06-01

    Accumulating evidence suggests that dopamine (DA) is involved in altering neural activity and gene expression in a zebra finch cortical-basal ganglia circuit specialized for singing, upon the shift between solitary singing and singing as a part of courtship. Our objective here was to sample changes in the extracellular concentrations of DA in Area X of adult and juvenile birds, to test the hypothesis that DA levels would change similarly during presentation of a socially salient stimulus in both age groups. We used microdialysis to sample the extracellular milieu of Area X in awake, behaving adult and juvenile male zebra finches, and analysed the dialysate using high-performance liquid chromatography coupled with electrochemical detection. The extracellular levels of DA in Area X increased significantly during both female presentation to adult males and tutor presentation to juvenile males. DA levels were not correlated with the time spent singing. We also reverse-dialysed Area X with pharmacologic agents that act either on DA systems directly or on norepinephrine, and found that all of these agents significantly increased DA levels (3- to 10-fold) in Area X. These findings suggest that changes in extracellular DA levels can be stimulated similarly by very different social contexts (courtship and interaction with tutor), and influenced potently by dopaminergic and noradrenergic drugs. These results raise the possibility that the arousal level or attentional state of the subject (rather than singing behavior) is the common feature eliciting changes in extracellular DA concentration. © 2015 The Authors. European Journal of Neuroscience published by Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  1. Growth and atrophy of neurons labeled at their birth in a song nucleus of the zebra finch

    International Nuclear Information System (INIS)

    Konishi, M.; Akutagawa, E.

    1990-01-01

    The robust nucleus of the archistriatum (RA) is one of the forebrain nuclei that control song production in birds. In the zebra finch (Poephila guttata), this nucleus contains more and larger neurons in the male than in the female. A single injection of tritiated thymidine into the egg on the 6th or 7th day of incubation resulted in labeling of many RA neurons with tritium. The size of tritium-labeled neurons and the tissue volume containing them did not differ between the sexes at 15 days after hatching. In the adult brain, tritium-labeled neurons and the tissue volume containing them were much larger in the male than in the female. Also, tritium-labeled RA neurons were large in females which received an implant of estrogen immediately after hatching. The gender differences in the neuron size and nuclear volume of the zebra finch RA are, therefore, due not to the replacement of old neurons by new ones during development but to the growth and atrophy of neurons born before hatching. Similarly, the masculinizing effects of estrogen on the female RA are due not to neuronal replacement but to the prevention of atrophy and promotion of growth in preexisting neurons

  2. Genoarchitecture of the extended amygdala in zebra finch, and expression of FoxP2 in cell corridors of different genetic profile.

    Science.gov (United States)

    Vicario, Alba; Mendoza, Ezequiel; Abellán, Antonio; Scharff, Constance; Medina, Loreta

    2017-01-01

    We used a battery of genes encoding transcription factors (Pax6, Islet1, Nkx2.1, Lhx6, Lhx5, Lhx9, FoxP2) and neuropeptides to study the extended amygdala in developing zebra finches. We identified different components of the central extended amygdala comparable to those found in mice and chickens, including the intercalated amygdalar cells, the central amygdala, and the lateral bed nucleus of the stria terminalis. Many cells likely originate in the dorsal striatal domain, ventral striatal domain, or the pallidal domain, as is the case in mice and chickens. Moreover, a cell subpopulation of the central extended amygdala appears to originate in the prethalamic eminence. As a general principle, these different cells with specific genetic profiles and embryonic origin form separate or partially intermingled cell corridors along the extended amygdala, which may be involved in different functional pathways. In addition, we identified the medial amygdala of the zebra finch. Like in the chickens and mice, it is located in the subpallium and is rich in cells of pallido-preoptic origin, containing minor subpopulations of immigrant cells from the ventral pallium, alar hypothalamus and prethalamic eminence. We also proposed that the medial bed nucleus of the stria terminalis is composed of several parallel cell corridors with different genetic profile and embryonic origin: preoptic, pallidal, hypothalamic, and prethalamic. Several of these cell corridors with distinct origin express FoxP2, a transcription factor implicated in synaptic plasticity. Our results pave the way for studies using zebra finches to understand the neural basis of social behavior, in which the extended amygdala is involved.

  3. Songbirds use pulse tone register in two voices to generate low-frequency sound

    DEFF Research Database (Denmark)

    Jensen, Kenneth Kragh; Cooper, Brenton G.; Larsen, Ole Næsbye

    2007-01-01

    , the syrinx, is unknown. We present the first high-speed video records of the intact syrinx during induced phonation. The syrinx of anaesthetized crows shows a vibration pattern of the labia similar to that of the human vocal fry register. Acoustic pulses result from short opening of the labia, and pulse...... generation alternates between the left and right sound sources. Spontaneously calling crows can also generate similar pulse characteristics with only one sound generator. Airflow recordings in zebra finches and starlings show that pulse tone sounds can be generated unilaterally, synchronously...

  4. Sexually dimorphic expression of the genes encoding ribosomal proteins L17 and L37 in the song control nuclei of juvenile zebra finches.

    Science.gov (United States)

    Tang, Yu Ping; Wade, Juli

    2006-12-18

    Studies evaluating the role of steroid hormones in sexual differentiation of the zebra finch song system have produced complicated and at times paradoxical results, and indicate that additional factors may be critical. Therefore, in a previous study we initiated a screen for differential gene expression in the telencephalon of developing male and female zebra finches. The use of cDNA microarrays and real-time quantitative PCR revealed increased expression of the genes encoding ribosomal proteins L17 and L37 (RPL17 and RPL37) in the male forebrain as a whole. Preliminary in situ hybridization data then indicated enhanced expression of both these genes in song control regions. Two experiments in the present study quantified the mRNA expression. The first utilized 25-day-old male and female zebra finches. The second compared a separate set of juveniles to adults of both sexes to both re-confirm enhanced expression in juvenile males and to determine whether it is limited to developing animals. In Experiment 1, males exhibited increased expression of both RPL17 and RPL37 compared to females in Area X, the robust nucleus of the arcopallium (RA), and the ventral ventricular zone (VVZ), which may provide neurons to Area X. Experiment 2 replicated the sexually dimorphic expression of these genes at post-hatching day 25, and documented that the sex differences are eliminated or greatly reduced in adults. The results are consistent with the idea that these ribosomal proteins may influence sexual differentiation of Area X and RA, potentially regulating the genesis and/or survival of neurons.

  5. Gaze strategy in the free flying zebra finch (Taeniopygia guttata.

    Directory of Open Access Journals (Sweden)

    Dennis Eckmeier

    Full Text Available Fast moving animals depend on cues derived from the optic flow on their retina. Optic flow from translational locomotion includes information about the three-dimensional composition of the environment, while optic flow experienced during a rotational self motion does not. Thus, a saccadic gaze strategy that segregates rotations from translational movements during locomotion will facilitate extraction of spatial information from the visual input. We analysed whether birds use such a strategy by highspeed video recording zebra finches from two directions during an obstacle avoidance task. Each frame of the recording was examined to derive position and orientation of the beak in three-dimensional space. The data show that in all flights the head orientation was shifted in a saccadic fashion and was kept straight between saccades. Therefore, birds use a gaze strategy that actively stabilizes their gaze during translation to simplify optic flow based navigation. This is the first evidence of birds actively optimizing optic flow during flight.

  6. Budgerigars and zebra finches differ in how they generalize in an artificial grammar learning experiment

    Science.gov (United States)

    Spierings, Michelle J.; ten Cate, Carel

    2016-01-01

    The ability to abstract a regularity that underlies strings of sounds is a core mechanism of the language faculty but might not be specific to language learning or even to humans. It is unclear whether and to what extent nonhuman animals possess the ability to abstract regularities defining the relation among arbitrary auditory items in a string and to generalize this abstraction to strings of acoustically novel items. In this study we tested these abilities in a songbird (zebra finch) and a parrot species (budgerigar). Subjects were trained in a go/no-go design to discriminate between two sets of sound strings arranged in an XYX or an XXY structure. After this discrimination was acquired, each subject was tested with test strings that were structurally identical to the training strings but consisted of either new combinations of known elements or of novel elements belonging to other element categories. Both species learned to discriminate between the two stimulus sets. However, their responses to the test strings were strikingly different. Zebra finches categorized test stimuli with previously heard elements by the ordinal position that these elements occupied in the training strings, independent of string structure. In contrast, the budgerigars categorized both novel combinations of familiar elements as well as strings consisting of novel element types by their underlying structure. They thus abstracted the relation among items in the XYX and XXY structures, an ability similar to that shown by human infants and indicating a level of abstraction comparable to analogical reasoning. PMID:27325756

  7. Three IgH isotypes, IgM, IgA and IgY are expressed in Gentoo penguin and zebra finch

    Science.gov (United States)

    Han, Haitang; Zhao, Yaofeng; Pan, Qingjie; Ren, Liming

    2017-01-01

    Previous studies on a limited number of birds suggested that the IgD-encoding gene was absent in birds. However, one of our recent studies showed that the gene was definitely expressed in the ostrich and emu. Interestingly, we also identified subclass diversification of IgM and IgY in these two birds. To better understand immunoglobulin genes in birds, in this study, we analyzed the immunoglobulin heavy chain genes in the zebra finch (Taeniopygia guttata) and Gentoo penguin (Pygoscelis papua), belonging respectively to the order Passeriformes, the most successful bird order in terms of species diversity and numbers, and Sphenisciformes, a relatively primitive avian order. Similar to the results obtained in chickens and ducks, only three genes encoding immunoglobulin heavy chain isotypes, IgM, IgA and IgY, were identified in both species. Besides, we detected a transcript encoding a short membrane-bound IgA lacking the last two CH exons in the Gentoo penguin. We did not find any evidence supporting the presence of IgD gene or subclass diversification of IgM/IgY in penguin or zebra finch. The obtained data in our study provide more insights into the immunoglobulin heavy chain genes in birds and may help to better understand the evolution of immunoglobulin genes in tetrapods. PMID:28403146

  8. Three IgH isotypes, IgM, IgA and IgY are expressed in Gentoo penguin and zebra finch.

    Science.gov (United States)

    Han, Binyue; Li, Yan; Han, Haitang; Zhao, Yaofeng; Pan, Qingjie; Ren, Liming

    2017-01-01

    Previous studies on a limited number of birds suggested that the IgD-encoding gene was absent in birds. However, one of our recent studies showed that the gene was definitely expressed in the ostrich and emu. Interestingly, we also identified subclass diversification of IgM and IgY in these two birds. To better understand immunoglobulin genes in birds, in this study, we analyzed the immunoglobulin heavy chain genes in the zebra finch (Taeniopygia guttata) and Gentoo penguin (Pygoscelis papua), belonging respectively to the order Passeriformes, the most successful bird order in terms of species diversity and numbers, and Sphenisciformes, a relatively primitive avian order. Similar to the results obtained in chickens and ducks, only three genes encoding immunoglobulin heavy chain isotypes, IgM, IgA and IgY, were identified in both species. Besides, we detected a transcript encoding a short membrane-bound IgA lacking the last two CH exons in the Gentoo penguin. We did not find any evidence supporting the presence of IgD gene or subclass diversification of IgM/IgY in penguin or zebra finch. The obtained data in our study provide more insights into the immunoglobulin heavy chain genes in birds and may help to better understand the evolution of immunoglobulin genes in tetrapods.

  9. An experimental test of condition-dependent male and female mate choice in zebra finches.

    Directory of Open Access Journals (Sweden)

    Marie-Jeanne Holveck

    Full Text Available In mating systems with social monogamy and obligatory bi-parental care, such as found in many songbird species, male and female fitness depends on the combined parental investment. Hence, both sexes should gain from choosing mates in high rather than low condition. However, theory also predicts that an individual's phenotypic quality can constrain choice, if low condition individuals cannot afford prolonged search efforts and/or face higher risk of rejection. In systems with mutual mate choice, the interaction between male and female condition should thus be a better predictor of choice than either factor in isolation. To address this prediction experimentally, we manipulated male and female condition and subsequently tested male and female mating preferences in zebra finches Taeniopygia guttata, a songbird species with mutual mate choice and obligatory bi-parental care. We experimentally altered phenotypic quality by manipulating the brood size in which the birds were reared. Patterns of association for high- or low-condition individuals of the opposite sex differed for male and female focal birds when tested in an 8-way choice arena. Females showed repeatable condition-assortative preferences for males matching their own rearing background. Male preferences were also repeatable, but not predicted by their own or females' rearing background. In combination with a brief review of the literature on condition-dependent mate choice in the zebra finch we discuss whether the observed sex differences and between-studies differences arise because males and females differ in context sensitivity (e.g. male-male competition suppressing male mating preferences, sampling strategies or susceptibility to rearing conditions (e.g. sex-specific effect on physiology. While a picture emerges that juvenile and current state indeed affect preferences, the development and context-dependency of mutual state-dependent mate choice warrants further study.

  10. The influence of inherited plumage colour morph on morphometric traits and breeding investment in zebra finches (Taeniopygia guttata.

    Directory of Open Access Journals (Sweden)

    E Tobias Krause

    Full Text Available Melanin-based plumage polymorphism occurs in many wild bird populations and has been linked to fitness variation in several species. These fitness differences often arise as a consequence of variation in traits such as behaviour, immune responsiveness, body size and reproductive investment. However, few studies have controlled for genetic differences between colour morphs that could potentially generate artefactual associations between plumage colouration and trait variation. Here, we used zebra finches (Taeniopygia guttata as a model system in order to evaluate whether life-history traits such as adult body condition and reproductive investment could be influenced by plumage morph. To maximise any potential differences, we selected wild-type and white plumage morphs, which differ maximally in their extent of melanisation, while using a controlled three-generation breeding design to homogenise the genetic background. We found that F2 adults with white plumage colouration were on average lighter and had poorer body condition than wild-type F2 birds. However, they appeared to compensate for this by reproducing earlier and producing heavier eggs relative to their own body mass. Our study thus reveals differences in morphological and life history traits that could be relevant to fitness variation, although further studies will be required to evaluate fitness effects under natural conditions as well as to characterise any potential fitness costs of compensatory strategies in white zebra finches.

  11. Myosin heavy-chain isoforms in the flight and leg muscles of hummingbirds and zebra finches.

    Science.gov (United States)

    Velten, Brandy P; Welch, Kenneth C

    2014-06-01

    Myosin heavy chain (MHC) isoform complement is intimately related to a muscle's contractile properties, yet relatively little is known about avian MHC isoforms or how they may vary with fiber type and/or the contractile properties of a muscle. The rapid shortening of muscles necessary to power flight at the high wingbeat frequencies of ruby-throated hummingbirds and zebra finches (25-60 Hz), along with the varied morphology and use of the hummingbird hindlimb, provides a unique opportunity to understand how contractile and morphological properties of avian muscle may be reflected in MHC expression. Isoforms of the hummingbird and zebra finch flight and hindlimb muscles were electrophoretically separated and compared with those of other avian species representing different contractile properties and fiber types. The flight muscles of the study species operate at drastically different contraction rates and are composed of different histochemically defined fiber types, yet each exhibited the same, single MHC isoform corresponding to the chicken adult fast isoform. Thus, despite quantitative differences in the contractile demands of flight muscles across species, this isoform appears necessary for meeting the performance demands of avian powered flight. Variation in flight muscle contractile performance across species may be due to differences in the structural composition of this conserved isoform and/or variation within other mechanically linked proteins. The leg muscles were more varied in their MHC isoform composition across both muscles and species. The disparity in hindlimb MHC expression between hummingbirds and the other species highlights previously observed differences in fiber type composition and thrust production during take-off. Copyright © 2014 the American Physiological Society.

  12. The roles of vocal and visual interactions in social learning zebra finches: A video playback experiment.

    Science.gov (United States)

    Guillette, Lauren M; Healy, Susan D

    2017-06-01

    The transmission of information from an experienced demonstrator to a naïve observer often depends on characteristics of the demonstrator, such as familiarity, success or dominance status. Whether or not the demonstrator pays attention to and/or interacts with the observer may also affect social information acquisition or use by the observer. Here we used a video-demonstrator paradigm first to test whether video demonstrators have the same effect as using live demonstrators in zebra finches, and second, to test the importance of visual and vocal interactions between the demonstrator and observer on social information use by the observer. We found that female zebra finches copied novel food choices of male demonstrators they saw via live-streaming video while they did not consistently copy from the demonstrators when they were seen in playbacks of the same videos. Although naive observers copied in the absence of vocalizations by the demonstrator, as they copied from playback of videos with the sound off, females did not copy where there was a mis-match between the visual information provided by the video and vocal information from a live male that was out of sight. Taken together these results suggest that video demonstration is a useful methodology for testing social information transfer, at least in a foraging context, but more importantly, that social information use varies according to the vocal interactions, or lack thereof, between the observer and the demonstrator. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  13. Diurnal and Reproductive Stage-Dependent Variation of Parental Behaviour in Captive Zebra Finches.

    Directory of Open Access Journals (Sweden)

    Boglárka Morvai

    Full Text Available Parental care plays a key role in ontogeny, life-history trade-offs, sexual selection and intra-familial conflict. Studies focusing on understanding causes and consequences of variation in parental effort need to quantify parental behaviour accurately. The applied methods are, however, diverse even for a given species and type of parental effort, and rarely validated for accuracy. Here we focus on variability of parental behaviour from a methodological perspective to investigate the effect of different samplings on various estimates of parental effort. We used nest box cameras in a captive breeding population of zebra finches, Taeniopygia guttata, a widely used model system of sexual selection, intra-familial dynamics and parental care. We investigated diurnal and reproductive stage-dependent variation in parental effort (including incubation, brooding, nest attendance and number of feedings based on 12h and 3h continuous video-recordings taken at various reproductive stages. We then investigated whether shorter (1h sampling periods provided comparable estimates of overall parental effort and division of labour to those of longer (3h sampling periods. Our study confirmed female-biased division of labour during incubation, and showed that the difference between female and male effort diminishes with advancing reproductive stage. We found individually consistent parental behaviours within given days of incubation and nestling provisioning. Furthermore, parental behaviour was consistent over the different stages of incubation, however, only female brooding was consistent over nestling provisioning. Parental effort during incubation did not predict parental effort during nestling provisioning. Our analyses revealed that 1h sampling may be influenced heavily by stochastic and diurnal variation. We suggest using a single longer sampling period (3h may provide a consistent and accurate estimate for overall parental effort during incubation in zebra

  14. Three IgH isotypes, IgM, IgA and IgY are expressed in Gentoo penguin and zebra finch.

    Directory of Open Access Journals (Sweden)

    Binyue Han

    Full Text Available Previous studies on a limited number of birds suggested that the IgD-encoding gene was absent in birds. However, one of our recent studies showed that the gene was definitely expressed in the ostrich and emu. Interestingly, we also identified subclass diversification of IgM and IgY in these two birds. To better understand immunoglobulin genes in birds, in this study, we analyzed the immunoglobulin heavy chain genes in the zebra finch (Taeniopygia guttata and Gentoo penguin (Pygoscelis papua, belonging respectively to the order Passeriformes, the most successful bird order in terms of species diversity and numbers, and Sphenisciformes, a relatively primitive avian order. Similar to the results obtained in chickens and ducks, only three genes encoding immunoglobulin heavy chain isotypes, IgM, IgA and IgY, were identified in both species. Besides, we detected a transcript encoding a short membrane-bound IgA lacking the last two CH exons in the Gentoo penguin. We did not find any evidence supporting the presence of IgD gene or subclass diversification of IgM/IgY in penguin or zebra finch. The obtained data in our study provide more insights into the immunoglobulin heavy chain genes in birds and may help to better understand the evolution of immunoglobulin genes in tetrapods.

  15. Behavioral Relevance of Species-Specific Vasotocin Anatomy in Gregarious Finches

    Directory of Open Access Journals (Sweden)

    Aubrey M Kelly

    2013-12-01

    Full Text Available Despite substantial species differences in the vasotocin/vasopressin (VT/VP circuitry of the medial bed nucleus of the stria terminalis (BSTm and lateral septum (LS; a primary projection target of BSTm VT/VP cells, functional consequences of this variation are poorly known. Previous experiments in the highly gregarious zebra finch (Estrildidae: Taeniopygia guttata demonstrate that BSTm VT neurons promote gregariousness in a male-specific manner and reduce anxiety in both sexes. However, in contrast to the zebra finch, the less gregarious Angolan blue waxbill (Estrildidae: Uraeginthus angolensis exhibits fewer VT-immunoreactive cells in the BSTm as well as differences in receptor distribution across the LS subnuclei, suggesting that knockdown of VT production in the BSTm would produce behavioral effects in Angolan blue waxbills that are distinct from zebra finches. Thus, we here quantified social contact, gregariousness (i.e. preference for the larger of two groups, and anxiety-like behavior following bilateral antisense knockdown of VT production in the BSTm of male and female Angolan blue waxbills. We find that BSTm VT neurons promote social contact, but not gregariousness (as in male zebra finches, and that antisense effects on social contact are significantly stronger in male waxbills than in females. Knockdown of BSTm VT production has no effect on anxiety-like behavior. These data provide novel evidence that species differences in the VT/VP circuitry arising in the BSTm are accompanied by species-specific effects on affiliation behaviors.

  16. Food, stress, and reproduction: short-term fasting alters endocrine physiology and reproductive behavior in the zebra finch.

    Science.gov (United States)

    Lynn, Sharon E; Stamplis, Teresa B; Barrington, William T; Weida, Nicholas; Hudak, Casey A

    2010-07-01

    Stress is thought to be a potent suppressor of reproduction. However, the vast majority of studies focus on the relationship between chronic stress and reproductive suppression, despite the fact that chronic stress is rare in the wild. We investigated the role of fasting in altering acute stress physiology, reproductive physiology, and reproductive behavior of male zebra finches (Taeniopygia guttata) with several goals in mind. First, we wanted to determine if acute fasting could stimulate an increase in plasma corticosterone and a decrease in corticosteroid binding globulin (CBG) and testosterone. We then investigated whether fasting could alter expression of undirected song and courtship behavior. After subjecting males to fasting periods ranging from 1 to 10h, we collected plasma to measure corticosterone, CBG, and testosterone. We found that plasma corticosterone was elevated, and testosterone was decreased after 4, 6, and 10h of fasting periods compared with samples collected from the same males during nonfasted (control) periods. CBG was lower than control levels only after 10h of fasting. We also found that, coincident with these endocrine changes, males sang less and courted females less vigorously following short-term fasting relative to control conditions. Our data demonstrate that acute fasting resulted in rapid changes in endocrine physiology consistent with hypothalamo-pituitary-adrenal axis activation and hypothalamo-pituitary-gonadal axis deactivation. Fasting also inhibited reproductive behavior. We suggest that zebra finches exhibit physiological and behavioral flexibility that makes them an excellent model system for studying interactions of acute stress and reproduction. Copyright 2010 Elsevier Inc. All rights reserved.

  17. The combined effect of lead exposure and high or low dietary calcium on health and immunocompetence in the zebra finch (Taeniopygia guttata)

    International Nuclear Information System (INIS)

    Snoeijs, Tinne; Dauwe, Tom; Pinxten, Rianne; Darras, Veerle M.; Arckens, Lutgarde; Eens, Marcel

    2005-01-01

    The widespread contamination by lead and the acidification of the environment ask for a better understanding of the effects of the interaction between lead and calcium on various aspects of health, including disease defense, in wildlife. Here, we investigated the effects of chronic exposure to sublethal levels of lead, combined with high or low dietary calcium, on health and several components of immunity in male and female zebra finches (Taeniopygia guttata). Thirty individuals of each sex were randomly assigned to three groups: a control group, a group exposed to lead with an additional calcium source (i.e. grit) and a group exposed to lead without access to an extra calcium source. Lead was administered as lead acetate via the drinking water (20 ppm) for 38 consecutive days. Exposure to lead increased significantly the concentrations of lead in kidney and bone in individuals of the experimental groups. Furthermore, the lack of a calcium supplement significantly enhanced the uptake of lead. Lead did not affect health indices such as hematocrit, spleen mass and body mass, nor the adrenal stress response. Cell-mediated immune responsiveness, assessed by a delayed-type hypersensitivity response to phytohaemagglutinin, was also not affected by lead exposure. On the other hand, lead exposure did significantly suppress the secondary humoral immune response towards sheep red blood cells in females, but only when the additional calcium source was not available. This effect was not found in males, suggesting sexual differences in susceptibility of humoral immunity to lead treatment in zebra finches. - Male and female finches may respond to lead differently

  18. Experimental Infection and Clearance of Coccidian Parasites in Mercury-Exposed Zebra Finches.

    Science.gov (United States)

    Ebers Smith, Jessica H; Cristol, Daniel A; Swaddle, John P

    2018-01-01

    Mercury is a globally distributed, persistent environmental contaminant that affects the health of many taxa. It can suppress the immune system, which often plays a role in defense against parasites. However, there have been few investigations of whether mercury affects the abilities of animals to resist parasitic infection. Here, we exposed zebra finches to a lifetime dietary exposure of methylmercury (1.2 μg/g wet weight) and experimentally infected them with coccidian parasites to examine the effect of methylmercury exposure on parasitic infection. The mercury-exposed birds did not have an altered immune response (heterophil:lymphocyte ratio) nor a reduced ability to clear the infection. However, mercury-exposed birds tended to have higher parasite loads at the time when we expected the greatest immune response (2-3 weeks post-infection). Although mercury did not greatly influence the infection-course of this parasite in captivity, responses may be more accentuated in the wild where birds face additional immune challenges.

  19. First Report of Coccidiosis and Gizzard Erosion in a Zebra Finch (Taeniopygia guttata of Iran

    Directory of Open Access Journals (Sweden)

    Moini, M.

    2012-06-01

    Full Text Available Coccidiosis and gizzard erosion are rare conditions in cage bird. A male zebra finch was presented with a history of watery diarrhea, anorexia, ruffled feathers, weight loss, and lethargy and died finally. Gross necropsy revealed small areas of erosions and hemorrhages on the gizzard wall. The intestine was oedematous. The spleen appeared pale and small. The testes were asymmetric.Histologically, necrosis of mucosal layer with infiltration of inflammatory cells observed in cecum. Eimeria stages were detected in the enterocytes. In Gizzard, hemorrhage and ulceration of mucosal layer with infiltration of polymorphonuclear cells in to the underlying mucosa were seen. In hepatic tissue, mild focal necrosis with mononuclear cells infiltration was seen. The disease was diagnosed as coccidiosis and gizzard erosion.

  20. Estradiol induces region-specific inhibition of ZENK but does not affect the behavioral preference for tutored song in adult female zebra finches

    OpenAIRE

    Svec, Lace A.; Wade, Juli

    2008-01-01

    Female zebra finches display a preference for songs of males raised with tutors compared to those from males without tutors. To determine howthis behavioral preference may bemediated by auditory perception sites, the social behavior network, and the dopamine reward system, and whether responses of these regions are affected by estradiol, females were treated with hormone or blank implants.An auditory choice test was conducted followed by exposure to tutored or untutored song or silence to exa...

  1. Ecologically-relevant exposure to methylmercury during early development does not affect adult phenotype in zebra finches (Taeniopygia guttata).

    Science.gov (United States)

    Morran, Spencer A M; Elliott, John E; Young, Jessica M L; Eng, Margaret L; Basu, Niladri; Williams, Tony D

    2018-04-01

    Methylmercury causes behavioural and reproductive effects in adult mammals via early developmental exposure. Similar studies in birds are limited and mostly focussed on aquatic systems, but recent work has reported high blood mercury concentrations in terrestrial, passerine songbirds. We used the zebra finch (Taeniopygia guttata) as a model to explore the long-term effects of early developmental exposure to methylmercury exposure. Chicks were dosed orally with either the vehicle control, 0.0315 µg Hg/g bw/day, or 0.075 µg Hg/g bw/day throughout the nestling period (days 1-21 post-hatching). We then measured (a) short-term effects on growth, development, and behaviour (time to self-feeding, neophobia) until 30 days of age (independence), and (b) long-term effects on courtship behaviour and song (males) and reproduction (females) once methylmercury-exposed birds reached sexual maturity (90 days post-hatching). High methylmercury treated birds had mean blood mercury of 0.734 ± 0.163 µg/g at 30 days post-hatching, within the range of values reported for field-sampled songbirds at mercury contaminated sites. However, there were no short-term effects of treatment on growth, development, and behaviour of chicks, and no long-term effects on courtship behaviour and song in males or reproductive performance in females. These results suggest that the nestling period is not a critical window for sensitivity to mercury exposure in zebra finches. Growing nestlings can reduce blood mercury levels through somatic growth and depuration into newly growing feathers, and as a result they might actually be less susceptible compared to adult birds receiving the same level of exposure.

  2. Patterns of call communication between group-housed zebra finches change during the breeding cycle.

    Science.gov (United States)

    Gill, Lisa F; Goymann, Wolfgang; Ter Maat, Andries; Gahr, Manfred

    2015-10-06

    Vocal signals such as calls play a crucial role for survival and successful reproduction, especially in group-living animals. However, call interactions and call dynamics within groups remain largely unexplored because their relation to relevant contexts or life-history stages could not be studied with individual-level resolution. Using on-bird microphone transmitters, we recorded the vocalisations of individual zebra finches (Taeniopygia guttata) behaving freely in social groups, while females and males previously unknown to each other passed through different stages of the breeding cycle. As birds formed pairs and shifted their reproductive status, their call repertoire composition changed. The recordings revealed that calls occurred non-randomly in fine-tuned vocal interactions and decreased within groups while pair-specific patterns emerged. Call-type combinations of vocal interactions changed within pairs and were associated with successful egg-laying, highlighting a potential fitness relevance of calling dynamics in communication systems.

  3. Form of Dietary Methylmercury does not Affect Total Mercury Accumulation in the Tissues of Zebra Finch.

    Science.gov (United States)

    Varian-Ramos, Claire W; Whitney, Margaret; Rice, Gary W; Cristol, Daniel A

    2017-07-01

    Exposure to mercury in humans, other mammals, and birds is primarily dietary, with mercury in the methylated form and bound to cysteine in the tissues of prey items. Yet dosing studies are generally carried out using methylmercury chloride. Here we tested whether the accumulation of total mercury in zebra finch blood, egg, muscle, liver, kidney or brain differed depending on whether dietary mercury was complexed with chloride or cysteine. We found no effect of form of mercury on tissue accumulation. Some previous studies have found lower accumulation of mercury in tissues of animals fed complexed mercury. Much remains to be understood about what happens to ingested mercury once it enters the intestines, but our results suggest that dietary studies using methylmercury chloride in birds will produce similar tissue accumulation levels to those using methylmercury cysteine.

  4. The tragedy of syrinx.

    Science.gov (United States)

    Demerdash, Amin; Loukas, Marios; Tubbs, R Shane

    2014-03-01

    Today, the term "syrinx" is used by many clinicians. Most users of the term, however, are not familiar with the origin of the word. The present paper reviews the history of the word syrinx, which is based in Greek mythology. Many modern terms have a derivation that is based on a rich history that has often been forgotten. The myth of Syrinx lives on in modern times by the continued use of syrinx in various words such as syringomyelia and syringe.

  5. Sexual Dimorphism in the Early Embryogenesis in Zebra Finches.

    Directory of Open Access Journals (Sweden)

    Makhsud Tagirov

    Full Text Available Sex-specific gene expression before the onset of gonadogensis has been documented in embryos of mammals and chickens. In several mammalian species, differences in gene expression are accompanied by faster growth of pre-implantation male embryos. Here we asked whether avian embryos before gonadal differentiation are also sex-dimorphic in size and what genes regulate their growth. We used captive zebra finches (Taeniopygia guttata whose freshly laid eggs were artificially incubated for 36-40 hours. Analyses controlling for the exact time of incubation of 81 embryos revealed that males were larger than females in terms of Hamburger and Hamilton stage and number of somites. Expression of 15 genes involved in cell cycle regulation, growth, metabolic activity, steroidogenic pathway and stress modulation were measured using RT-PCR in 5 male and 5 female embryos incubated for exactly 36 h. We found that in the presence of equal levels of the growth hormone itself, the faster growth of male embryos is most likely achieved by the overexpression of the growth hormone receptor gene and three other genes responsible for cell cycle regulation and metabolism, all of them located on the Z chromosome. Autosomal genes did not show sex-specific expression, except for the steroidogenic factor 1 which was expressed only in female embryos. To our knowledge this is the first report of sexual size dimorphism before gonadogenesis in birds. The finding suggests that faster growth of early male embryos is conserved through the mammalian and bird phyla, irrespective of their differential sex chromosome systems.

  6. Magnetic resonance imaging of syrinx cavity. Differentiation between syrinx with spinal cord tumor and without tumor

    Energy Technology Data Exchange (ETDEWEB)

    Fukuda, Teruo; Inoue, Yuichi; Nemoto, Yutaka

    1987-12-01

    Syrinx cavity may result from a number of intramedullary tumors or non-neoplastic conditions such as Chiari malformation, trauma and meningitis. The surgical procedure to repair the syrinx is quite different between the cases with spinal cord tumor and without tumor. Therefore, it is important to determine whether syrinx is associated with tumor or not before surgery. We reviewed MR images of 26 cases with syrinx cavity; 20 of which were not associated with tumor (12 Chiari malformation, 5 trauma, 1 meningitis, 1 hydrocephalus, 1 idiopathic) and 6 of which were associated with intramedullary tumor (3 ependymoma, 2 astrocytoma, 1 hemangioendothelioma). The syrinx showed low signal in all 26 cases on T1 weighted images (SE 600/40). All 6 cases with syrinx associated with intramedullary tumor showed high intensity on T2 weighted images (SE 2000/120). On the other hand, the syrinx of 19 of 20 cases with no tumor condition showed reduced intensity on T2 weighted images. Only one post-traumatic small syrinx showed high signal. This was quite different between the cases with spinal cord tumor and without tumor. Therefore, when the syrinx cavity shows high signal on T2 weighted images, an intramedullary tumor is strongly suggested.

  7. Sex Differences in Brain Thyroid Hormone Levels during Early Post-Hatching Development in Zebra Finch (Taeniopygia guttata.

    Directory of Open Access Journals (Sweden)

    Shinji Yamaguchi

    Full Text Available Thyroid hormones are closely linked to the hatching process in precocial birds. Previously, we showed that thyroid hormones in brain had a strong impact on filial imprinting, an early learning behavior in newly hatched chicks; brain 3,5,3'-triiodothyronine (T3 peaks around hatching and imprinting training induces additional T3 release, thus, extending the sensitive period for imprinting and enabling subsequent other learning. On the other hand, blood thyroid hormone levels have been reported to increase gradually after hatching in altricial species, but it remains unknown how the brain thyroid hormone levels change during post-hatching development of altricial birds. Here, we determined the changes in serum and brain thyroid hormone levels of a passerine songbird species, the zebra finch using radioimmunoassay. In the serum, we found a gradual increase in thyroid hormone levels during post-hatching development, as well as differences between male and female finches. In the brain, there was clear surge in the hormone levels during development in males and females coinciding with the time of fledging, but the onset of the surge of thyroxine (T4 in males preceded that of females, whereas the onset of the surge of T3 in males succeeded that of females. These findings provide a basis for understanding the functions of thyroid hormones during early development and learning in altricial birds.

  8. Sex Differences in Brain Thyroid Hormone Levels during Early Post-Hatching Development in Zebra Finch (Taeniopygia guttata).

    Science.gov (United States)

    Yamaguchi, Shinji; Hayase, Shin; Aoki, Naoya; Takehara, Akihiko; Ishigohoka, Jun; Matsushima, Toshiya; Wada, Kazuhiro; Homma, Koichi J

    2017-01-01

    Thyroid hormones are closely linked to the hatching process in precocial birds. Previously, we showed that thyroid hormones in brain had a strong impact on filial imprinting, an early learning behavior in newly hatched chicks; brain 3,5,3'-triiodothyronine (T3) peaks around hatching and imprinting training induces additional T3 release, thus, extending the sensitive period for imprinting and enabling subsequent other learning. On the other hand, blood thyroid hormone levels have been reported to increase gradually after hatching in altricial species, but it remains unknown how the brain thyroid hormone levels change during post-hatching development of altricial birds. Here, we determined the changes in serum and brain thyroid hormone levels of a passerine songbird species, the zebra finch using radioimmunoassay. In the serum, we found a gradual increase in thyroid hormone levels during post-hatching development, as well as differences between male and female finches. In the brain, there was clear surge in the hormone levels during development in males and females coinciding with the time of fledging, but the onset of the surge of thyroxine (T4) in males preceded that of females, whereas the onset of the surge of T3 in males succeeded that of females. These findings provide a basis for understanding the functions of thyroid hormones during early development and learning in altricial birds.

  9. Mitochondria-targeted molecules determine the redness of the zebra finch bill.

    Science.gov (United States)

    Cantarero, Alejandro; Alonso-Alvarez, Carlos

    2017-10-01

    The evolution and production mechanisms of red carotenoid-based ornaments in animals are poorly understood. Recently, it has been suggested that enzymes transforming yellow carotenoids to red pigments (ketolases) in animal cells may be positioned in the inner mitochondrial membrane (IMM) intimately linked to the electron transport chain. These enzymes may mostly synthesize coenzyme Q 10 (coQ 10 ), a key redox-cycler antioxidant molecularly similar to yellow carotenoids. It has been hypothesized that this shared pathway favours the evolution of red traits as sexually selected individual quality indices by revealing a well-adjusted oxidative metabolism. We administered mitochondria-targeted molecules to male zebra finches ( Taeniopygia guttata ) measuring their bill redness, a trait produced by transforming yellow carotenoids. One molecule included coQ 10 (mitoquinone mesylate, MitoQ) and the other one (decyl-triphenylphosphonium; dTPP) has the same structure without the coQ 10 aromatic ring. At the highest dose, the bill colour of MitoQ and dTPP birds strongly differed: MitoQ birds' bills were redder and dTPP birds showed paler bills even compared to birds injected with saline only. These results suggest that ketolases are indeed placed at the IMM and that coQ 10 antioxidant properties may improve their efficiency. The implications for evolutionary theories of sexual signalling are discussed. © 2017 The Author(s).

  10. Increased fat catabolism sustains water balance during fasting in zebra finches.

    Science.gov (United States)

    Rutkowska, Joanna; Sadowska, Edyta T; Cichoń, Mariusz; Bauchinger, Ulf

    2016-09-01

    Patterns of physiological flexibility in response to fasting are well established, but much less is known about the contribution of water deprivation to the observed effects. We investigated body composition and energy and water budget in three groups of zebra finches: birds with access to food and water, food-deprived birds having access to drinking water and food-and-water-deprived birds. Animals were not stimulated by elevated energy expenditure and they were in thermoneutral conditions; thus, based on previous studies, water balance of fasting birds was expected to be maintained by increased catabolism of proteins. In contrast to this expectation, we found that access to water did not prevent reduction of proteinaceous tissue, but it saved fat reserves of the fasting birds. Thus, water balance of birds fasting without access to water seemed to be maintained by elevated fat catabolism, which generated 6 times more metabolic water compared with that in birds that had access to water. Therefore, we revise currently established views and propose fat to serve as the primary source for metabolic water production. Previously assumed increased protein breakdown for maintenance of water budget would occur if fat stores were depleted or if fat catabolism reached its upper limits due to high energy demands. © 2016. Published by The Company of Biologists Ltd.

  11. Early-Life Stress Triggers Juvenile Zebra Finches to Switch Social Learning Strategies.

    Science.gov (United States)

    Farine, Damien R; Spencer, Karen A; Boogert, Neeltje J

    2015-08-17

    Stress during early life can cause disease and cognitive impairment in humans and non-humans alike. However, stress and other environmental factors can also program developmental pathways. We investigate whether differential exposure to developmental stress can drive divergent social learning strategies between siblings. In many species, juveniles acquire essential foraging skills by copying others: they can copy peers (horizontal social learning), learn from their parents (vertical social learning), or learn from other adults (oblique social learning). However, whether juveniles' learning strategies are condition dependent largely remains a mystery. We found that juvenile zebra finches living in flocks socially learned novel foraging skills exclusively from adults. By experimentally manipulating developmental stress, we further show that social learning targets are phenotypically plastic. While control juveniles learned foraging skills from their parents, their siblings, exposed as nestlings to experimentally elevated stress hormone levels, learned exclusively from unrelated adults. Thus, early-life conditions triggered individuals to switch strategies from vertical to oblique social learning. This switch could arise from stress-induced differences in developmental rate, cognitive and physical state, or the use of stress as an environmental cue. Acquisition of alternative social learning strategies may impact juveniles' fit to their environment and ultimately change their developmental trajectories. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  12. Magnetic resonance imaging of syrinx cavity

    International Nuclear Information System (INIS)

    Fukuda, Teruo; Inoue, Yuichi; Nemoto, Yutaka

    1987-01-01

    Syrinx cavity may result from a number of intramedullary tumors or non-neoplastic conditions such as Chiari malformation, trauma and meningitis. The surgical procedure to repair the syrinx is quite different between the cases with spinal cord tumor and without tumor. Therefore, it is important to determine whether syrinx is associated with tumor or not before surgery. We reviewed MR images of 26 cases with syrinx cavity; 20 of which were not associated with tumor (12 Chiari malformation, 5 trauma, 1 meningitis, 1 hydrocephalus, 1 idiopathic) and 6 of which were associated with intramedullary tumor (3 ependymoma, 2 astrocytoma, 1 hemangioendothelioma). The syrinx showed low signal in all 26 cases on T1 weighted images (SE 600/40). All 6 cases with syrinx associated with intramedullary tumor showed high intensity on T2 weighted images (SE 2000/120). On the other hand, the syrinx of 19 of 20 cases with no tumor condition showed reduced intensity on T2 weighted images. Only one post-traumatic small syrinx showed high signal. This was quite different between the cases with spinal cord tumor and without tumor. Therefore, when the syrinx cavity shows high signal on T2 weighted images, an intramedullary tumor is strongly suggested. (author)

  13. Metabolic and respiratory costs of increasing song amplitude in zebra finches.

    Directory of Open Access Journals (Sweden)

    Sue Anne Zollinger

    Full Text Available Bird song is a widely used model in the study of animal communication and sexual selection, and several song features have been shown to reflect the quality of the singer. Recent studies have demonstrated that song amplitude may be an honest signal of current condition in males and that females prefer high amplitude songs. In addition, birds raise the amplitude of their songs to communicate in noisy environments. Although it is generally assumed that louder song should be more costly to produce, there has been little empirical evidence to support this assumption. We tested the assumption by measuring oxygen consumption and respiratory patterns in adult male zebra finches (Taeniopygia guttata singing at different amplitudes in different background noise conditions. As background noise levels increased, birds significantly increased the sound pressure level of their songs. We found that louder songs required significantly greater subsyringeal air sac pressure than quieter songs. Though increased pressure is probably achieved by increasing respiratory muscle activity, these increases did not correlate with measurable increases in oxygen consumption. In addition, we found that oxygen consumption increased in higher background noise, independent of singing behaviour. This observation supports previous research in mammals showing that high levels of environmental noise can induce physiological stress responses. While our study did not find that increasing vocal amplitude increased metabolic costs, further research is needed to determine whether there are other non-metabolic costs of singing louder or costs associated with chronic noise exposure.

  14. Mercury alters initiation and construction of nests by zebra finches, but not incubation or provisioning behaviors.

    Science.gov (United States)

    Chin, Stephanie Y; Hopkins, William A; Cristol, Daniel A

    2017-11-01

    Mercury is an environmental contaminant that impairs avian reproduction, but the behavioral and physiological mechanisms underlying this effect are poorly understood. The objective of this study was to determine whether lifetime dietary exposure to mercury (1.2 µg/g wet weight in food) impacted avian parental behaviors, and how this might influence reproductive success. To distinguish between the direct effects of mercury on parents and offspring, we created four treatment groups of captive-bred zebra finches (Taeniopygia guttata), with control and mercury-exposed adults raising cross-fostered control or mercury-exposed eggs (from maternal transfer). Control parents were 23% more likely to fledge young than parents exposed to mercury, regardless of egg exposure. Mercury-exposed parents were less likely to initiate nests than controls and spent less time constructing them. Nests of mercury-exposed pairs were lighter, possibly due to an impaired ability to bring nest material into the nestbox. However, nest temperature, incubation behavior, and provisioning rate did not differ between parental treatments. Unexposed control eggs tended to have shorter incubation periods and higher hatching success than mercury-exposed eggs, but there was no effect of parental exposure on these parameters. We accidentally discovered that parent finches transfer some of their body burden of mercury to nestlings during feeding through secretion in the crop. These results suggest that, in mercury-exposed songbirds, pre-laying parental behaviors, combined with direct exposure of embryos to mercury, likely contribute to reduced reproductive success and should be considered in future studies. Further research is warranted in field settings, where parents are exposed to greater environmental challenges and subtle behavioral differences might have more serious consequences than were observed in captivity.

  15. Cannabinoid mitigation of neuronal morphological change important to development and learning: insight from a zebra finch model of psychopharmacology.

    Science.gov (United States)

    Soderstrom, Ken; Gilbert, Marcoita T

    2013-03-19

    Normal CNS development proceeds through late-postnatal stages of adolescent development. The activity-dependence of this development underscores the significance of CNS-active drug exposure prior to completion of brain maturation. Exogenous modulation of signaling important in regulating normal development is of particular concern. This mini-review presents a summary of the accumulated behavioral, physiological and biochemical evidence supporting such a key regulatory role for endocannabinoid signaling during late-postnatal CNS development. Our focus is on the data obtained using a unique zebra finch model of developmental psychopharmacology. This animal has allowed investigation of neuronal morphological effects essential to establishment and maintenance of neural circuitry, including processes related to synaptogenesis and dendritic spine dynamics. Altered neurophysiology that follows exogenous cannabinoid exposure during adolescent development has the potential to persistently alter cognition, learning and memory. Copyright © 2012 Elsevier Inc. All rights reserved.

  16. Heterologous Synapsis and Crossover Suppression in Heterozygotes for a Pericentric Inversion in the Zebra Finch.

    Science.gov (United States)

    del Priore, Lucía; Pigozzi, María I

    2015-01-01

    In the zebra finch, 2 alternative morphs regarding centromere position were described for chromosome 6. This polymorphism was interpreted to be the result of a pericentric inversion, but other causes of the centromere repositioning were not ruled out. We used immunofluorescence localization to examine the distribution of MLH1 foci on synaptonemal complexes to test the prediction that pericentric inversions cause synaptic irregularities and/or crossover suppression in heterozygotes. We found complete suppression of crossing over in the region involved in the rearrangement in male and female heterozygotes. In contrast, the same region showed high levels of crossing over in homozygotes for the acrocentric form of this chromosome. No inversion loops or synaptic irregularities were detected along bivalent 6 in heterozygotes suggesting that heterologous pairing is achieved during zygotene or early pachytene. Altogether these findings strongly indicate that the polymorphic chromosome 6 originated by a pericentric inversion. Since inversions are common rearrangements in karyotypic evolution in birds, it seems likely that early heterologous pairing could help to fix these rearrangements, preventing crossing overs in heterozygotes and their deleterious effects on fertility. © 2015 S. Karger AG, Basel.

  17. Syringeal specialization of frequency control during song production in the Bengalese finch (Lonchura striata domestica.

    Directory of Open Access Journals (Sweden)

    Kristen R Secora

    Full Text Available Singing in songbirds is a complex, learned behavior which shares many parallels with human speech. The avian vocal organ (syrinx has two potential sound sources, and each sound generator is under unilateral, ipsilateral neural control. Different songbird species vary in their use of bilateral or unilateral phonation (lateralized sound production and rapid switching between left and right sound generation (interhemispheric switching of motor control. Bengalese finches (Lonchura striata domestica have received considerable attention, because they rapidly modify their song in response to manipulations of auditory feedback. However, how the left and right sides of the syrinx contribute to acoustic control of song has not been studied.Three manipulations of lateralized syringeal control of sound production were conducted. First, unilateral syringeal muscular control was eliminated by resection of the left or right tracheosyringeal portion of the hypoglossal nerve, which provides neuromuscular innervation of the syrinx. Spectral and temporal features of song were compared before and after lateralized nerve injury. In a second experiment, either the left or right sound source was devoiced to confirm the role of each sound generator in the control of acoustic phonology. Third, air pressure was recorded before and after unilateral denervation to enable quantification of acoustic change within individual syllables following lateralized nerve resection.These experiments demonstrate that the left sound source produces louder, higher frequency, lower entropy sounds, and the right sound generator produces lower amplitude, lower frequency, higher entropy sounds. The bilateral division of labor is complex and the frequency specialization is the opposite pattern observed in most songbirds. Further, there is evidence for rapid interhemispheric switching during song production. Lateralized control of song production in Bengalese finches may enhance acoustic

  18. Short- and long-term consequences of early developmental conditions: a case study on wild and domesticated zebra finches.

    Science.gov (United States)

    Tschirren, B; Rutstein, A N; Postma, E; Mariette, M; Griffith, S C

    2009-02-01

    Divergent selection pressures among populations can result not only in significant differentiation in morphology, physiology and behaviour, but also in how these traits are related to each other, thereby driving the processes of local adaptation and speciation. In the Australian zebra finch, we investigated whether domesticated stock, bred in captivity over tens of generations, differ in their response to a life-history manipulation, compared to birds taken directly from the wild. In a 'common aviary' experiment, we thereto experimentally manipulated the environmental conditions experienced by nestlings early in life by means of a brood size manipulation, and subsequently assessed its short- and long-term consequences on growth, ornamentation, immune function and reproduction. As expected, we found that early environmental conditions had a marked effect on both short- and long-term morphological and life-history traits in all birds. However, although there were pronounced differences between wild and domesticated birds with respect to the absolute expression of many of these traits, which are indicative of the different selection pressures wild and domesticated birds were exposed to in the recent past, manipulated rearing conditions affected morphology and ornamentation of wild and domesticated finches in a very similar way. This suggests that despite significant differentiation between wild and domesticated birds, selection has not altered the relationships among traits. Thus, life-history strategies and investment trade-offs may be relatively stable and not easily altered by selection. This is a reassuring finding in the light of the widespread use of domesticated birds in studies of life-history evolution and sexual selection, and suggests that adaptive explanations may be legitimate when referring to captive bird studies.

  19. Insights into the evolution of Darwin’s finches from comparative analysis of the Geospiza magnirostris genome sequence

    Directory of Open Access Journals (Sweden)

    Rands Chris M

    2013-02-01

    Full Text Available Abstract Background A classical example of repeated speciation coupled with ecological diversification is the evolution of 14 closely related species of Darwin’s (Galápagos finches (Thraupidae, Passeriformes. Their adaptive radiation in the Galápagos archipelago took place in the last 2–3 million years and some of the molecular mechanisms that led to their diversification are now being elucidated. Here we report evolutionary analyses of genome of the large ground finch, Geospiza magnirostris. Results 13,291 protein-coding genes were predicted from a 991.0 Mb G. magnirostris genome assembly. We then defined gene orthology relationships and constructed whole genome alignments between the G. magnirostris and other vertebrate genomes. We estimate that 15% of genomic sequence is functionally constrained between G. magnirostris and zebra finch. Genic evolutionary rate comparisons indicate that similar selective pressures acted along the G. magnirostris and zebra finch lineages suggesting that historical effective population size values have been similar in both lineages. 21 otherwise highly conserved genes were identified that each show evidence for positive selection on amino acid changes in the Darwin's finch lineage. Two of these genes (Igf2r and Pou1f1 have been implicated in beak morphology changes in Darwin’s finches. Five of 47 genes showing evidence of positive selection in early passerine evolution have cilia related functions, and may be examples of adaptively evolving reproductive proteins. Conclusions These results provide insights into past evolutionary processes that have shaped G. magnirostris genes and its genome, and provide the necessary foundation upon which to build population genomics resources that will shed light on more contemporaneous adaptive and non-adaptive processes that have contributed to the evolution of the Darwin’s finches.

  20. Effects of estradiol on incorporation of new cells in the developing zebra finch song system: potential relationship to expression of ribosomal proteins L17 and L37.

    Science.gov (United States)

    Tang, Yu Ping; Wade, Juli

    2009-06-01

    Mechanisms regulating masculinization of the zebra finch song system are unclear; both estradiol and sex-specific genes may be important. This study was designed to investigate relationships between estrogen and ribosomal proteins (RPL17 and RPL37; sex-linked genes) that exhibit greater expression in song control nuclei in juvenile males than females. Four studies on zebra finches were conducted using bromodeoxyuridine (BrdU) injections on posthatching days 6-10 with immunohistochemistry for the ribosomal proteins and the neuronal marker HuC/D at day 25. Volumes of brain regions were also assessed in Nissl-stained tissue. Most BrdU+ cells expressed RPL17 and RPL37. The density and percentage of cells co-expressing BrdU and HuC/D was greatest in Area X. The density of BrdU+ cells in Area X (or its equivalent) and the percentage of these cells that were neurons were greater in males than females. In RA and HVC, total BrdU+ cells were increased in males. A variety of effects of estradiol were also detected, including inducing an Area X in females with a masculine total number of BrdU+ cells, and increasing the volume and percentage of new neurons in the HVC of females. The same manipulation in males decreased the density of BrdU+ cells in Area X, total number of BrdU+ cells in RA, and density of new neurons in HVC and RA. These data are consistent with the idea that RPL17, RPL37, and estradiol might all influence sexual differentiation, perhaps with the hormone and proteins interacting, such that an appropriate balance is required for normal development.

  1. Genomic organization and molecular phylogenies of the beta (β keratin multigene family in the chicken (Gallus gallus and zebra finch (Taeniopygia guttata: implications for feather evolution

    Directory of Open Access Journals (Sweden)

    Sawyer Roger H

    2010-05-01

    Full Text Available Abstract Background The epidermal appendages of reptiles and birds are constructed of beta (β keratins. The molecular phylogeny of these keratins is important to understanding the evolutionary origin of these appendages, especially feathers. Knowing that the crocodilian β-keratin genes are closely related to those of birds, the published genomes of the chicken and zebra finch provide an opportunity not only to compare the genomic organization of their β-keratins, but to study their molecular evolution in archosaurians. Results The subfamilies (claw, feather, feather-like, and scale of β-keratin genes are clustered in the same 5' to 3' order on microchromosome 25 in chicken and zebra finch, although the number of claw and feather genes differs between the species. Molecular phylogenies show that the monophyletic scale genes are the basal group within birds and that the monophyletic avian claw genes form the basal group to all feather and feather-like genes. Both species have a number of feather clades on microchromosome 27 that form monophyletic groups. An additional monophyletic cluster of feather genes exist on macrochromosome 2 for each species. Expression sequence tag analysis for the chicken demonstrates that all feather β-keratin clades are expressed. Conclusions Similarity in the overall genomic organization of β-keratins in Galliformes and Passeriformes suggests similar organization in all Neognathae birds, and perhaps in the ancestral lineages leading to modern birds, such as the paravian Anchiornis huxleyi. Phylogenetic analyses demonstrate that evolution of archosaurian epidermal appendages in the lineage leading to birds was accompanied by duplication and divergence of an ancestral β-keratin gene cluster. As morphological diversification of epidermal appendages occurred and the β-keratin multigene family expanded, novel β-keratin genes were selected for novel functions within appendages such as feathers.

  2. Systemic Amyloidosis and Testicular Interstitial Tumor in a Zebra Finch (Taeniopygia guttata: a Case Report in Iran

    Directory of Open Access Journals (Sweden)

    Mehrnoush Moeini Jazani

    2011-09-01

    Full Text Available Abstract Systemic amyloidosis and testicular interstitial tumor are rare conditions in birds and this is the first report in Iran. A male zebra finch was presented because of white diarrhea, anorexia, loss of weight and lethargy. At necropsy, the small intestine was edematous and congested. The spleen appeared pale. The liver was large, firm and brown. One testis was cystic and neoplastic and the remaining testis was atrophic. Histologically, amyloid materials were seen predominantly in the liver and spleen. Hyaline substances were deposited in the Disse space and in the media of blood vessels of the liver. In spleen, marked deposits thickened the basement membranes of blood vessels and extended into the surrounding parenchyma. In addition, there were lesser degrees of amyloidosis in other organs such as small intestine. Amyloid stained positively with Congo red. In testis, there was encapsulated unilateral interstitial cell tumor, with multiple foci of necrosis and hemorrhage. The neoplastic cells were round to polyhedral, with small round hyperchromatic nuclei and finely vacuolated cytoplasm. Signs of feminization were observed. The cause of amyloidosis in this study was not conclusively identified.

  3. Impulsiveness does not prevent cooperation from emerging but reduces its occurrence: an experiment with zebra finches.

    Science.gov (United States)

    Chia, Camille; Dubois, Frédérique

    2017-08-17

    Reciprocal altruism, the most probable mechanism for cooperation among unrelated individuals, can be modelled as a Prisoner's Dilemma. This game predicts that cooperation should evolve whenever the players, who expect to interact repeatedly, make choices contingent to their partner's behaviour. Experimental evidence, however, indicates that reciprocity is rare among animals. One reason for this would be that animals are very impulsive compared to humans. Several studies have reported that temporal discounting (that is, strong preferences for immediate benefits) has indeed a negative impact on the occurrence of cooperation. Yet, the role of impulsive action, another facet of impulsiveness, remains unexplored. Here, we conducted a laboratory experiment in which male and female zebra finches (Taenyopigia guttata) were paired assortatively with respect to their level of impulsive action and then played an alternating Prisoner's Dilemma. As anticipated, we found that self-controlled pairs achieved high levels of cooperation by using a Generous Tit-for-Tat strategy, while impulsive birds that cooperated at a lower level, chose to cooperate with a fixed probability. If the inability of impulsive individuals to use reactive strategies are due to their reduced working memory capacity, thus our findings might contribute to explaining interspecific differences in cooperative behaviour.

  4. Large-scale synchronized activity during vocal deviance detection in the zebra finch auditory forebrain.

    Science.gov (United States)

    Beckers, Gabriël J L; Gahr, Manfred

    2012-08-01

    Auditory systems bias responses to sounds that are unexpected on the basis of recent stimulus history, a phenomenon that has been widely studied using sequences of unmodulated tones (mismatch negativity; stimulus-specific adaptation). Such a paradigm, however, does not directly reflect problems that neural systems normally solve for adaptive behavior. We recorded multiunit responses in the caudomedial auditory forebrain of anesthetized zebra finches (Taeniopygia guttata) at 32 sites simultaneously, to contact calls that recur probabilistically at a rate that is used in communication. Neurons in secondary, but not primary, auditory areas respond preferentially to calls when they are unexpected (deviant) compared with the same calls when they are expected (standard). This response bias is predominantly due to sites more often not responding to standard events than to deviant events. When two call stimuli alternate between standard and deviant roles, most sites exhibit a response bias to deviant events of both stimuli. This suggests that biases are not based on a use-dependent decrease in response strength but involve a more complex mechanism that is sensitive to auditory deviance per se. Furthermore, between many secondary sites, responses are tightly synchronized, a phenomenon that is driven by internal neuronal interactions rather than by the timing of stimulus acoustic features. We hypothesize that this deviance-sensitive, internally synchronized network of neurons is involved in the involuntary capturing of attention by unexpected and behaviorally potentially relevant events in natural auditory scenes.

  5. Blocking estradiol synthesis affects memory for songs in auditory forebrain of male zebra finches.

    Science.gov (United States)

    Yoder, Kathleen M; Lu, Kai; Vicario, David S

    2012-11-14

    Estradiol (E2) has recently been shown to modulate sensory processing in an auditory area of the songbird forebrain, the caudomedial nidopallium (NCM). When a bird hears conspecific song, E2 increases locally in NCM, where neurons express both the aromatase enzyme that synthesizes E2 from precursors and estrogen receptors. Auditory responses in NCM show a form of neuronal memory: repeated playback of the unique learned vocalizations of conspecific individuals induces long-lasting stimulus-specific adaptation of neural responses to each vocalization. To test the role of E2 in this auditory memory, we treated adult male zebra finches (n=16) with either the aromatase inhibitor fadrozole (FAD) or saline for 8 days. We then exposed them to 'training' songs and, 6 h later, recorded multiunit auditory responses with an array of 16 microelectrodes in NCM. Adaptation rates (a measure of stimulus-specific adaptation) to playbacks of training and novel songs were computed, using established methods, to provide a measure of neuronal memory. Recordings from the FAD-treated birds showed a significantly reduced memory for the training songs compared with saline-treated controls, whereas auditory processing for novel songs did not differ between treatment groups. In addition, FAD did not change the response bias in favor of conspecific over heterospecific song stimuli. Our results show that E2 depletion affects the neuronal memory for vocalizations in songbird NCM, and suggest that E2 plays a necessary role in auditory processing and memory for communication signals.

  6. MC1R genotype and plumage colouration in the zebra finch (Taeniopygia guttata: population structure generates artefactual associations.

    Directory of Open Access Journals (Sweden)

    Joseph I Hoffman

    Full Text Available Polymorphisms at the melanocortin-1 receptor (MC1R gene have been linked to coloration in many vertebrate species. However, the potentially confounding influence of population structure has rarely been controlled for. We explored the role of the MC1R in a model avian system by sequencing the coding region in 162 zebra finches comprising 79 wild type and 83 white individuals from five stocks. Allelic counts differed significantly between the two plumage morphs at multiple segregating sites, but these were mostly synonymous. To provide a control, the birds were genotyped at eight microsatellites and subjected to Bayesian cluster analysis, revealing two distinct groups. We therefore crossed wild type with white individuals and backcrossed the F1s with white birds. No significant associations were detected in the resulting offspring, suggesting that our original findings were a byproduct of genome-wide divergence. Our results are consistent with a previous study that found no association between MC1R polymorphism and plumage coloration in leaf warblers. They also contribute towards a growing body of evidence suggesting that care should be taken to quantify, and where necessary control for, population structure in association studies.

  7. Stressful dieting: nutritional conditions but not compensatory growth elevate corticosterone levels in zebra finch nestlings and fledglings.

    Directory of Open Access Journals (Sweden)

    Mariam Honarmand

    Full Text Available Unfavourable conditions throughout the period of parental care can severely affect growth, reproductive performance, and survival. Yet, individuals may be affected differently, depending on the developmental period during which constraints are experienced. Here we tested whether the nestling phase compared to the fledgling phase is more susceptible to nutritional stress by considering biometry, physiology, sexually selected male ornaments and survival using zebra finches (Taeniopygia guttata as a model species. As nestlings (day 0-17 or fledglings (day 17-35, subjects were raised either on low or high quality food. A low quality diet resulted in significantly elevated baseline corticosterone titres in both nestlings and fledglings. Subjects showed substantial compensatory growth after they had experienced low quality food as nestlings but catch-up growth did neither lead to elevated baseline corticosterone titres nor did we detect long term effects on biometry, male cheek patch, or survival. The compensation for temporally unfavourable environmental conditions reflects substantial phenotypic plasticity and the results show that costs of catch-up growth were not mediated via corticosterone as a physiological correlate of allostatic load. These findings provide new insights into the mechanisms and plasticity with which animals respond to periods of constraints during development as they may occur in a mistiming of breeding.

  8. Syrinx of the Spinal Cord and Brain Stem

    Science.gov (United States)

    ... and problems with eye movements, taste, and speech. Magnetic resonance imaging can detect a syrinx. Surgery to drain the syrinx may be done, but ... young child or teenager who has typical symptoms. Magnetic resonance imaging (MRI) of the entire spinal cord and ... of the cause when possible A neurosurgeon ...

  9. Maternal antibody transfer can lead to suppression of humoral immunity in developing zebra finches (Taeniopygia guttata).

    Science.gov (United States)

    Merrill, Loren; Grindstaff, Jennifer L

    2014-01-01

    Maternally transferred antibodies have been documented in a wide range of taxa and are thought to adaptively provide protection against parasites and pathogens while the offspring immune system is developing. In most birds, transfer occurs when females deposit immunoglobulin Y into the egg yolk, and it is proportional to the amount in the female's plasma. Maternal antibodies can provide short-term passive protection as well as specific and nonspecific immunological priming, but high levels of maternal antibody can result in suppression of the offspring's humoral immune response. We injected adult female zebra finches (Taeniopygia guttata) with one of two antigens (lipopolysaccharide [LPS] or keyhole limpet hemocyanin [KLH]) or a control and then injected offspring with LPS, KLH, or a control on days 5 and 28 posthatch to examine the impact of maternally transferred antibodies on the ontogeny of the offspring's humoral immune system. We found that offspring of females exposed to KLH had elevated levels of KLH-reactive antibody over the first 17-28 days posthatch but reduced KLH-specific antibody production between days 28 and 36. We also found that offspring exposed to either LPS or KLH exhibited reduced total antibody levels, compared to offspring that received a control injection. These results indicate that high levels of maternal antibodies or antigen exposure during development can have negative repercussions on short-term antibody production and may have long-term fitness repercussions for the offspring.

  10. Exploring vocal recovery after cranial nerve injury in Bengalese finches.

    Science.gov (United States)

    Urbano, Catherine M; Peterson, Jennifer R; Cooper, Brenton G

    2013-02-08

    Songbirds and humans use auditory feedback to acquire and maintain their vocalizations. The Bengalese finch (Lonchura striata domestica) is a songbird species that rapidly modifies its vocal output to adhere to an internal song memory. In this species, the left side of the bipartite vocal organ is specialized for producing louder, higher frequencies (≥2.2kHz) and denervation of the left vocal muscles eliminates these notes. Thus, the return of higher frequency notes after cranial nerve injury can be used as a measure of vocal recovery. Either the left or right side of the syrinx was denervated by resection of the tracheosyringeal portion of the hypoglossal nerve. Histologic analyses of syringeal muscle tissue showed significant muscle atrophy in the denervated side. After left nerve resection, songs were mainly composed of lower frequency syllables, but three out of five birds recovered higher frequency syllables. Right nerve resection minimally affected phonology, but it did change song syntax; syllable sequence became abnormally stereotyped after right nerve resection. Therefore, damage to the neuromuscular control of sound production resulted in reduced motor variability, and Bengalese finches are a potential model for functional vocal recovery following cranial nerve injury. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  11. Male foraging efficiency, but not male problem-solving performance, influences female mating preferences in zebra finches

    Directory of Open Access Journals (Sweden)

    Véronique Chantal

    2016-08-01

    Full Text Available Experimental evidence suggests that females would prefer males with better cognitive abilities as mates. However, little is known about the traits reflecting enhanced cognitive skills on which females might base their mate-choice decisions. In particular, it has been suggested that male foraging performance could be used as an indicator of cognitive capacity, but convincing evidence for this hypothesis is still lacking. In the present study, we investigated whether female zebra finches (Taeniopygia guttata modify their mating preferences after having observed the performance of males on a problem-solving task. Specifically, we measured the females’ preferences between two males once before and once after an observation period, during which their initially preferred male was incapable of solving the task contrary to their initially less-preferred male. We also conducted a control treatment to test whether the shift in female preferences was attributable to differences between the two stimulus males in their foraging efficiency. Finally, we assessed each bird’s performance in a color associative task to check whether females can discriminate among males based on their learning speed. We found that females significantly increased their preference toward the most efficient male in both treatments. Yet, there was no difference between the two treatments and we found no evidence that females assess male cognitive ability indirectly via morphological traits. Thus, our results suggest that females would not use the males’ problem-solving performance as an indicator of general cognitive ability to gain indirect fitness benefits (i.e., good genes but rather to assess their foraging efficiency and gain direct benefits.

  12. Prolactin is related to individual differences in parental behavior and reproductive success in a biparental passerine, the zebra finch (Taeniopygia guttata).

    Science.gov (United States)

    Smiley, Kristina O; Adkins-Regan, Elizabeth

    2016-08-01

    Variation in parental care can lead to important fitness consequences. The endocrine system is known to regulate physiological and behavioral reproductive traits that are important contributors to lifetime reproductive success. However, the hormonal basis of variation in avian parental care is still not well understood. Plasma prolactin (PRL) concentrations are generally high during post-hatch parental care in birds, and may be a candidate mechanism that regulates variation in parental care and other reproductive success outcomes. Here we analyze the relationship between PRL, parental behavior (chick brooding and feeding) and reproductive success outcomes (clutch size, number of chicks hatched, and chick survival) for the first time in the zebra finch (Taeniopygia guttata). Birds were given cabergoline, a dopamine agonist traditionally used to lower prolactin in mammals, or vehicle in their food. Cabergoline had no effect on prolactin concentrations, but across both groups we found that PRL is positively correlated with parental behavior, number of chicks hatched, and chick survival, but not clutch size. Results from this study will inform hypotheses and predictions for future manipulation studies which test for a causal role for PRL in parental traits. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. From electromyographic activity to frequency modulation in zebra finch song.

    Science.gov (United States)

    Döppler, Juan F; Bush, Alan; Goller, Franz; Mindlin, Gabriel B

    2018-02-01

    Behavior emerges from the interaction between the nervous system and peripheral devices. In the case of birdsong production, a delicate and fast control of several muscles is required to control the configuration of the syrinx (the avian vocal organ) and the respiratory system. In particular, the syringealis ventralis muscle is involved in the control of the tension of the vibrating labia and thus affects the frequency modulation of the sound. Nevertheless, the translation of the instructions (which are electrical in nature) into acoustical features is complex and involves nonlinear, dynamical processes. In this work, we present a model of the dynamics of the syringealis ventralis muscle and the labia, which allows calculating the frequency of the generated sound, using as input the electrical activity recorded in the muscle. In addition, the model provides a framework to interpret inter-syllabic activity and hints at the importance of the biomechanical dynamics in determining behavior.

  14. Activity in a premotor cortical nucleus of zebra finches is locally organized and exhibits auditory selectivity in neurons but not in glia.

    Directory of Open Access Journals (Sweden)

    Michael H Graber

    Full Text Available Motor functions are often guided by sensory experience, most convincingly illustrated by complex learned behaviors. Key to sensory guidance in motor areas may be the structural and functional organization of sensory inputs and their evoked responses. We study sensory responses in large populations of neurons and neuron-assistive cells in the songbird motor area HVC, an auditory-vocal brain area involved in sensory learning and in adult song production. HVC spike responses to auditory stimulation display remarkable preference for the bird's own song (BOS compared to other stimuli. Using two-photon calcium imaging in anesthetized zebra finches we measure the spatio-temporal structure of baseline activity and of auditory evoked responses in identified populations of HVC cells. We find strong correlations between calcium signal fluctuations in nearby cells of a given type, both in identified neurons and in astroglia. In identified HVC neurons only, auditory stimulation decorrelates ongoing calcium signals, less for BOS than for other sound stimuli. Overall, calcium transients show strong preference for BOS in identified HVC neurons but not in astroglia, showing diversity in local functional organization among identified neuron and astroglia populations.

  15. Encoding of naturalistic optic flow by motion sensitive neurons of nucleus rotundus in the zebra finch (Taeniopygia guttata.

    Directory of Open Access Journals (Sweden)

    Dennis eEckmeier

    2013-09-01

    Full Text Available The retinal image changes that occur during locomotion, the optic flow, carry information about self-motion and the three-dimensional structure of the environment. Especially fast moving animals with only little binocular vision depend on these depth cues for manoeuvring. They actively control their gaze to facilitate perception of depth based on cues in the optic flow. In the visual system of birds, nucleus rotundus neurons were originally found to respond to object motion but not to background motion. However, when background and object were both moving, responses increase the more the direction and velocity of object and background motion on the retina differed. These properties may play a role in representing depth cues in the optic flow. We therefore investigated how neurons in nucleus rotundus respond to optic flow that contains depth cues. We presented simplified and naturalistic optic flow on a panoramic LED display while recording from single neurons in nucleus rotundus of anaesthetized zebra finches. Unlike most studies on motion vision in birds, our stimuli included depth information.We found extensive responses of motion selective neurons in nucleus rotundus to optic flow stimuli. Simplified stimuli revealed preferences for optic flow reflecting translational or rotational self-motion. Naturalistic optic flow stimuli elicited complex response modulations, but the presence of objects was signalled by only few neurons. The neurons that did respond to objects in the optic flow, however, show interesting properties.

  16. Effects of acute corticosterone treatment on partner preferences in male and female zebra finches (Taeniopygia guttata).

    Science.gov (United States)

    LaPlante, Kimberly A; Huremovic, Enida; Tomaszycki, Michelle L

    2014-04-01

    Stress alters physiology and behavior across species. Most research on the effects of stress on behavior uses chronic stressors, and most are correlational. The effects of acute stressors on physiology and behavior have been mixed. Here, we use zebra finches, a highly gregarious species that forms long-term pair bonds, to test the effects of an acute corticosterone (CORT) on opposite-sex partner preferences over a same-sex individual or a group (the latter is a highly appealing option). We had two competing hypotheses. First, we predicted that acute CORT would alter preferences for the opposite sex bird in both conditions in both sexes. However, since there is a sex difference in the effects of CORT on partner preferences in voles, these effects may be more pronounced in males than in females. To test our hypotheses, we administered 2 doses of CORT (10μg and 20μg) or vehicle (control) using a repeated measures design. In the male vs. female test, there was a significant Sex by Treatment interaction, such that in males, 10μg CORT increased preferences for a female over the male compared to when these same males were treated with saline at baseline. There were no effects of treatment in females. In the opposite-sex vs. group condition, there was an overall effect of Treatment, such that the 10μg dose increased preference for the opposite-sex individual over both saline treatments, regardless of sex. These findings further our understanding of the effects of an acute stressor on sexual partner preferences. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. Syrinx - a research program for the pulsed power radiation facility

    International Nuclear Information System (INIS)

    Etlicher, B.; Chuvatin, A.S.; Choi, P.

    1996-01-01

    Syrinx is a targeted research program with the objective to study, through practical examples, the fundamentals necessary to define the details of all parts which will be required for a new powerful plasma radiation source. The current level of activities of Syrinx is in the design and construction of a multi-megajoule class IES based pulsed power driver which will use long conduction Plasma Opening Switch technology. The present paper reviews mainly the basic experimental research of the POS a nd Z-pinch accomplished in the framework of Syrinx project. This work has a unique international level of participation, from conceptual designs to particular investigations. (author). 9 figs., 17 refs

  18. Effect of laying sequence on egg mercury in captive zebra finches: an interpretation considering individual variation.

    Science.gov (United States)

    Ou, Langbo; Varian-Ramos, Claire W; Cristol, Daniel A

    2015-08-01

    Bird eggs are used widely as noninvasive bioindicators for environmental mercury availability. Previous studies, however, have found varying relationships between laying sequence and egg mercury concentrations. Some studies have reported that the mercury concentration was higher in first-laid eggs or declined across the laying sequence, whereas in other studies mercury concentration was not related to egg order. Approximately 300 eggs (61 clutches) were collected from captive zebra finches dosed throughout their reproductive lives with methylmercury (0.3 μg/g, 0.6 μg/g, 1.2 μg/g, or 2.4 μg/g wet wt in diet); the total mercury concentration (mean ± standard deviation [SD] dry wt basis) of their eggs was 7.03 ± 1.38 μg/g, 14.15 ± 2.52 μg/g, 26.85 ± 5.85 μg/g, and 49.76 ± 10.37 μg/g, respectively (equivalent to fresh wt egg mercury concentrations of 1.24 μg/g, 2.50 μg/g, 4.74 μg/g, and 8.79 μg/g). The authors observed a significant decrease in the mercury concentration of successive eggs when compared with the first egg and notable variation between clutches within treatments. The mercury level of individual females within and among treatments did not alter this relationship. Based on the results, sampling of a single egg in each clutch from any position in the laying sequence is sufficient for purposes of population risk assessment, but it is not recommended as a proxy for individual female exposure or as an estimate of average mercury level within the clutch. © 2015 SETAC.

  19. Activation changes in zebra finch (Taeniopygia guttata) brain areas evoked by alterations of the earth magnetic field.

    Science.gov (United States)

    Keary, Nina; Bischof, Hans-Joachim

    2012-01-01

    Many animals are able to perceive the earth magnetic field and to use it for orientation and navigation within the environment. The mechanisms underlying the perception and processing of magnetic field information within the brain have been thoroughly studied, especially in birds, but are still obscure. Three hypotheses are currently discussed, dealing with ferromagnetic particles in the beak of birds, with the same sort of particles within the lagena organs, or describing magnetically influenced radical-pair processes within retinal photopigments. Each hypothesis is related to a well-known sensory organ and claims parallel processing of magnetic field information with somatosensory, vestibular and visual input, respectively. Changes in activation within nuclei of the respective sensory systems have been shown previously. Most of these previous experiments employed intensity enhanced magnetic stimuli or lesions. We here exposed unrestrained zebra finches to either a stationary or a rotating magnetic field of the local intensity and inclination. C-Fos was used as an activity marker to examine whether the two treatments led to differences in fourteen brain areas including nuclei of the somatosensory, vestibular and visual system. An ANOVA revealed an overall effect of treatment, indicating that the magnetic field change was perceived by the birds. While the differences were too small to be significant in most areas, a significant enhancement of activation by the rotating stimulus was found in a hippocampal subdivision. Part of the hyperpallium showed a strong, nearly significant, increase. Our results are compatible with previous studies demonstrating an involvement of at least three different sensory systems in earth magnetic field perception and suggest that these systems, probably less elaborated, may also be found in nonmigrating birds.

  20. Early fasting is long lasting: differences in early nutritional conditions reappear under stressful conditions in adult female zebra finches.

    Directory of Open Access Journals (Sweden)

    E Tobias Krause

    Full Text Available Conditions experienced during early life can have profound effects on individual development and condition in adulthood. Differences in nutritional provisioning in birds during the first month of life can lead to differences in growth, reproductive success and survival. Yet, under natural conditions shorter periods of nutritional stress will be more prevalent. Individuals may respond differently, depending on the period of development during which nutritional stress was experienced. Such differences may surface specifically when poor environmental conditions challenge individuals again as adults. Here, we investigated long term consequences of differences in nutritional conditions experienced during different periods of early development by female zebra finches (Taeniopygia guttata on measures of management and acquisition of body reserves. As nestlings or fledglings, subjects were raised under different nutritional conditions, a low or high quality diet. After subjects reached sexual maturity, we measured their sensitivity to periods of food restriction, their exploration and foraging behaviour as well as adult resting metabolic rate (RMR. During a short period of food restriction, subjects from the poor nutritional conditions had a higher body mass loss than those raised under qualitatively superior nutritional conditions. Moreover, subjects that were raised under poor nutritional conditions were faster to engage in exploratory and foraging behaviour. But RMR did not differ among treatments. These results reveal that early nutritional conditions affect adult exploratory behaviour, a representative personality trait, foraging and adult's physiological condition. As early nutritional conditions are reflected in adult phenotypic plasticity specifically when stressful situations reappear, the results suggest that costs for poor developmental conditions are paid when environmental conditions deteriorate.

  1. Implications of nutritional stress as nestling or fledgling on subsequent attractiveness and fecundity in zebra finches (Taeniopygia guttata

    Directory of Open Access Journals (Sweden)

    Mariam Honarmand

    2017-08-01

    Full Text Available The conditions an organism experiences during early development can have profound and long lasting effects on its subsequent behavior, attractiveness, and life history decisions. Most previous studies have exposed individuals to different conditions throughout development until nutritional independence. Yet under natural conditions, individuals may experience limitations for much shorter periods due to transient environmental fluctuations. Here, we used zebra finches (Taeniopygia guttata in captivity to determine if conditions experienced during distinctly different early developmental phases contribute differently to male and female attractiveness and subsequent reproduction. We conducted a breeding experiment in which offspring were exposed to food regimes with (a low quality food provided only during the nestling period, (b low quality food provided only during the fledgling period, or (c high quality food throughout early development. We show that despite short-term effects on biometry and physiology, there were no effects on either male or female attractiveness, as tested in two-way mate choice free-flight aviary experiments. In a subsequent breeding experiment, the offspring from the initial experiment were allowed to breed themselves. The next generation offspring from mothers raised under lower quality nutrition as either nestling or fledging were lighter at hatching compared to offspring from mothers raised under higher quality nutrition whereas paternal early nutrition had no such effects. The lack of early developmental limitations on attractiveness suggests that attractiveness traits were not affected or that birds compensated for any such effects. Furthermore, maternal trans-generational effects of dietary restrictions emphasize the importance of role of limited periods of early developmental stress in the expression of environmentally determined fitness components.

  2. Implications of nutritional stress as nestling or fledgling on subsequent attractiveness and fecundity in zebra finches (Taeniopygia guttata).

    Science.gov (United States)

    Honarmand, Mariam; Krause, E Tobias; Naguib, Marc

    2017-01-01

    The conditions an organism experiences during early development can have profound and long lasting effects on its subsequent behavior, attractiveness, and life history decisions. Most previous studies have exposed individuals to different conditions throughout development until nutritional independence. Yet under natural conditions, individuals may experience limitations for much shorter periods due to transient environmental fluctuations. Here, we used zebra finches ( Taeniopygia guttata ) in captivity to determine if conditions experienced during distinctly different early developmental phases contribute differently to male and female attractiveness and subsequent reproduction. We conducted a breeding experiment in which offspring were exposed to food regimes with (a) low quality food provided only during the nestling period, (b) low quality food provided only during the fledgling period, or (c) high quality food throughout early development. We show that despite short-term effects on biometry and physiology, there were no effects on either male or female attractiveness, as tested in two-way mate choice free-flight aviary experiments. In a subsequent breeding experiment, the offspring from the initial experiment were allowed to breed themselves. The next generation offspring from mothers raised under lower quality nutrition as either nestling or fledging were lighter at hatching compared to offspring from mothers raised under higher quality nutrition whereas paternal early nutrition had no such effects. The lack of early developmental limitations on attractiveness suggests that attractiveness traits were not affected or that birds compensated for any such effects. Furthermore, maternal trans-generational effects of dietary restrictions emphasize the importance of role of limited periods of early developmental stress in the expression of environmentally determined fitness components.

  3. Pan, Syrinx and syringomyelia.

    Science.gov (United States)

    Palacios-Sánchez, Leonardo; Botero-Meneses, Juan Sebastián; Vélez-Flórez, María Camila

    2017-12-01

    Many myths and legends have had a deep influence on modern language, and on modern medical vernacular. The terms "syrinx" and "panic"are two of the most characteristic examples and their use in neurology and other specialties is well known. This article reviews the history of these words in Greek mythology and their use in modern medicine. It is known by very few that clinical symptoms or conditions, such as syringomyelia and panic attacks, have a mythological origin in their definition and naming.

  4. Evidence for cholinergic participation in the control of bird song; acetylcholinesterase distribution and muscarinic receptor autoradiography in the zebra finch brain

    International Nuclear Information System (INIS)

    Ryan, S.M.; Arnold, A.P.

    1981-01-01

    Brain regions thought to be involved in the control of song in the zebra finch (Poephila guttata), were examined histochemically using the Karnovsky and Roots direct-coloring method for the detection of acetylcholinesterase (AChE) and the autoradiographic method for the localization of muscarinic cholinergic receptors following injection of tritiated quinuclidinyl benzilate (3H QNB). All presently identified vocal control nuclei in both males and females contain AChE. These nuclei include Area X, magnocellular nucleus of the anterior neostriatum (MAN), nucleus interface (NIF), caudal nucleus of the hyperstriatum ventrale (HVc), intercollicular nucleus (ICo), nucleus uva, robust nucleus of the archistriatum (RA), and tracheosyringeal portion of the hypoglossal nerve nucleus (nXIIts). All nuclei except Area X contain mostly AChE-synthesizing cell bodies. All of these nuclei contain some AChE in the neuropil, with particularly intense staining in Area X, the surrounding LPO, and the dorsomedial portion of ICo. In agreement with this description are very high concentrations of 3H QNB in both Area X and the dorsomedial ICo. HVc also appears specifically labeled. Evidence from these two histological technique suggests that efferent projections of most vocal control area may utilize acetylcholine, and that several of the vocal control nuclei may themselves receive muscarinic cholinergic projection. In Area X, there are sex differences of AChE neuropil staining. This evidence suggesting that sexually dimorphic projections to or within Area X are cholinergic or cholinoceptive

  5. Sex- and age-related differences in ribosomal proteins L17 and L37, as well as androgen receptor protein, in the song control system of zebra finches.

    Science.gov (United States)

    Tang, Y P; Wade, J

    2010-12-29

    The zebra finch song system is sexually dimorphic--only males sing, and the morphology of forebrain regions controlling the learning and production of this song is greatly enhanced in males compared to females. Masculinization appears to involve effects of steroid hormones as well as other factors, perhaps including the expression of sex chromosome genes (males: ZZ, females: ZW). The present study investigated three proteins--two encoded by Z-linked genes, ribosomal proteins L17 and L37 (RPL17 and RPL37), including their co-localization with androgen receptor (AR), from post-hatching day 25 to adulthood. Extensive co-expression of AR with the ribosomal proteins was detected in the three song nuclei investigated (HVC, robust nucleus of the arcopallium (RA), and Area X) across these ages. In general, more cells expressed each of these proteins in males compared to females, and the sex differences increased as animals matured. Specific patterns differed across regions and between RPL17 and RPL37, which suggest potential roles of one or both of these proteins in the incorporation and/or differentiation of song system cells. Copyright © 2010 IBRO. Published by Elsevier Ltd. All rights reserved.

  6. Sex determination of duck embryos: observations on syrinx development

    Science.gov (United States)

    Wilson, Robert E.; Sonsthagen, Sarah A.; Franson, J. Christian

    2013-01-01

    Ducks exhibit sexual dimorphism in vocal anatomy. Asymmetrical ossification of the syrinx (bulla syringealis) is discernable at about 10 days of age in male Pekin duck (Anas platyrhynchos domestica) embryos, but information is lacking on the early development of the bulla in wild ducks. To evaluate the reliability of this characteristic for sexing developing embryos, we examined the syrinx of dead embryos and compared results with molecular sexing techniques in high arctic nesting Common Eiders (Somateria mollissima). Embryos 8 days or older were accurately (100%) sexed based on the presence/absence of a bulla, 2 days earlier than Pekin duck. The use of the tracheal bulla can be a valuable technique when sex identification of embryos or young ducklings is required.

  7. Mercury reduces avian reproductive success and imposes selection: an experimental study with adult- or lifetime-exposure in zebra finch.

    Directory of Open Access Journals (Sweden)

    Claire W Varian-Ramos

    Full Text Available Mercury is a global pollutant that biomagnifies in food webs, placing wildlife at risk of reduced reproductive fitness and survival. Songbirds are the most diverse branch of the avian evolutionary tree; many are suffering persistent and serious population declines and we know that songbirds are frequently exposed to mercury pollution. Our objective was to determine the effects of environmentally relevant doses of mercury on reproductive success of songbirds exposed throughout their lives or only as adults. The two modes of exposure simulated philopatric species versus dispersive species, and are particularly relevant because of the heightened mercury-sensitivity of developing nervous systems. We performed a dosing study with dietary methylmercury in a model songbird species, the zebra finch (Taeniopygia guttata, at doses from 0.3 - 2.4 parts per million. Birds were exposed to mercury either as adults only or throughout their lives. All doses of mercury reduced reproductive success, with the lowest dose reducing the number of independent offspring produced in one year by 16% and the highest dose, representing approximately half the lethal dose for this species, causing a 50% reduction. While mercury did not affect clutch size or survivorship, it had the most consistent effect on the proportion of chicks that fledged from the nest, regardless of mode of exposure. Among birds exposed as adults, mercury caused a steep increase in the latency to re-nest after loss of a clutch. Birds exposed for their entire lifetimes, which were necessarily the offspring of dosed parents, had up to 50% lower reproductive success than adult-exposed birds at low doses of methylmercury, but increased reproductive success at high doses, suggesting selection for mercury tolerance at the highest level of exposure. Our results indicate that mercury levels in prey items at contaminated sites pose a significant threat to populations of songbirds through reduced reproductive

  8. Food for Song: Expression of C-Fos and ZENK in the Zebra Finch Song Nuclei during Food Aversion Learning

    Science.gov (United States)

    Tokarev, Kirill; Tiunova, Anna

    2011-01-01

    Background Specialized neural pathways, the song system, are required for acquiring, producing, and perceiving learned avian vocalizations. Birds that do not learn to produce their vocalizations lack telencephalic song system components. It is not known whether the song system forebrain regions are exclusively evolved for song or whether they also process information not related to song that might reflect their ‘evolutionary history’. Methodology/Principal Findings To address this question we monitored the induction of two immediate-early genes (IEGs) c-Fos and ZENK in various regions of the song system in zebra finches (Taeniopygia guttata) in response to an aversive food learning paradigm; this involves the association of a food item with a noxious stimulus that affects the oropharyngeal-esophageal cavity and tongue, causing subsequent avoidance of that food item. The motor response results in beak and head movements but not vocalizations. IEGs have been extensively used to map neuro-molecular correlates of song motor production and auditory processing. As previously reported, neurons in two pallial vocal motor regions, HVC and RA, expressed IEGs after singing. Surprisingly, c-Fos was induced equivalently also after food aversion learning in the absence of singing. The density of c-Fos positive neurons was significantly higher than that of birds in control conditions. This was not the case in two other pallial song nuclei important for vocal plasticity, LMAN and Area X, although singing did induce IEGs in these structures, as reported previously. Conclusions/Significance Our results are consistent with the possibility that some of the song nuclei may participate in non-vocal learning and the populations of neurons involved in the two tasks show partial overlap. These findings underscore the previously advanced notion that the specialized forebrain pre-motor nuclei controlling song evolved from circuits involved in behaviors related to feeding. PMID:21695176

  9. Mercury Reduces Avian Reproductive Success and Imposes Selection: An Experimental Study with Adult- or Lifetime-Exposure in Zebra Finch

    Science.gov (United States)

    Varian-Ramos, Claire W.; Swaddle, John P.; Cristol, Daniel A.

    2014-01-01

    Mercury is a global pollutant that biomagnifies in food webs, placing wildlife at risk of reduced reproductive fitness and survival. Songbirds are the most diverse branch of the avian evolutionary tree; many are suffering persistent and serious population declines and we know that songbirds are frequently exposed to mercury pollution. Our objective was to determine the effects of environmentally relevant doses of mercury on reproductive success of songbirds exposed throughout their lives or only as adults. The two modes of exposure simulated philopatric species versus dispersive species, and are particularly relevant because of the heightened mercury-sensitivity of developing nervous systems. We performed a dosing study with dietary methylmercury in a model songbird species, the zebra finch (Taeniopygia guttata), at doses from 0.3 – 2.4 parts per million. Birds were exposed to mercury either as adults only or throughout their lives. All doses of mercury reduced reproductive success, with the lowest dose reducing the number of independent offspring produced in one year by 16% and the highest dose, representing approximately half the lethal dose for this species, causing a 50% reduction. While mercury did not affect clutch size or survivorship, it had the most consistent effect on the proportion of chicks that fledged from the nest, regardless of mode of exposure. Among birds exposed as adults, mercury caused a steep increase in the latency to re-nest after loss of a clutch. Birds exposed for their entire lifetimes, which were necessarily the offspring of dosed parents, had up to 50% lower reproductive success than adult-exposed birds at low doses of methylmercury, but increased reproductive success at high doses, suggesting selection for mercury tolerance at the highest level of exposure. Our results indicate that mercury levels in prey items at contaminated sites pose a significant threat to populations of songbirds through reduced reproductive success. PMID

  10. Immunohistochemical localization of cocaine- and amphetamine-regulated transcript peptide (CARTp) in the brain of the pigeon (Columba livia) and zebra finch (Taeniopygia guttata).

    Science.gov (United States)

    Gutierrez-Ibanez, Cristian; Iwaniuk, Andrew N; Jensen, Megan; Graham, David J; Pogány, Ákos; Mongomery, Benjamin C; Stafford, James L; Luksch, Harald; Wylie, Douglas R

    2016-12-15

    Cocaine- and amphetamine-regulated transcript peptides (CARTp) are neuropeptides that act as neurotransmitters in the brain of vertebrates. The expression of CARTp has been characterized in teleosts, amphibians, and several mammalian species, but comparative data in reptiles and birds are nonexistent. In this study, we show the distribution of immunoreactivity against CART peptides (CARTp-ir) in the brains of two bird species: the pigeon (Columba livia) and zebra finch (Taeniopygia guttata). We found CARTp-ir cells and terminals in the brains of both, but no major differences between the two species. As in mammals, teleost fish, and amphibians, CARTp-ir terminals and cells were abundant in subpallial regions, particularly the striatum and nucleus accumbens. We also found CARTp-ir cells and terminals in the hypothalamus, and a large number of CARTp-ir terminals in the substantia nigra, ventral tegmental area, periaqueductal gray, parabrachial nucleus, and dorsal vagal complex. However, in contrast to other vertebrates, CARTp-ir was not found in the olfactory bulb. In addition there was almost no CARTp-ir in the pallium or the hippocampal formation, and little CARTp-ir in the cerebellum. The conserved expression of CARTp in the subpallium, hypothalamus, and dorsal vagal complex of birds suggests that some of the functions of CARTp, such as regulation of food intake and interactions with the social control network and mesolimbic reward system, are conserved among vertebrates. J. Comp. Neurol. 524:3747-3773, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  11. Are olfactory cues involved in nest recognition in two social species of estrildid finches?

    Directory of Open Access Journals (Sweden)

    E Tobias Krause

    Full Text Available Reliably recognizing their own nest provides parents with a necessary skill to invest time and resources efficiently in raising their offspring and thereby maximising their own reproductive success. Studies investigating nest recognition in adult birds have focused mainly on visual cues of the nest or the nest site and acoustic cues of the nestlings. To determine whether adult songbirds also use olfaction for nest recognition, we investigated the use of olfactory nest cues for two estrildid finch species, zebra finches (Taeniopygia guttata and Bengalese finches (Lonchura striata var. domestica during the nestling and fledgling phase of their offspring. We found similar behavioural responses to nest odours in both songbird species. Females preferred the odour of their own nest over a control and avoided the foreign conspecific nest scent over a control during the nestling phase of their offspring, but when given the own odour and the foreign conspecific odour simultaneously we did not find a preference for the own nest odour. Males of both species did not show any preferences at all. The behavioural reaction to any nest odour decreased after fledging of the offspring. Our results show that only females show a behavioural response to olfactory nest cues, indicating that the use of olfactory cues for nest recognition seems to be sex-specific and dependent on the developmental stage of the offspring. Although estrildid finches are known to use visual and acoustic cues for nest recognition, the similar behavioural pattern of both species indicates that at least females gain additional information by olfactory nest cues during the nestling phase of their offspring. Thus olfactory cues might be important in general, even in situations in which visual and acoustic cues are known to be sufficient.

  12. Song tutoring in presinging zebra finch juveniles biases a small population of higher-order song-selective neurons toward the tutor song.

    Science.gov (United States)

    Adret, Patrice; Meliza, C Daniel; Margoliash, Daniel

    2012-10-01

    We explored physiological changes correlated with song tutoring by recording the responses of caudal nidopallium neurons of zebra finches aged P21-P24 (days post hatching) to a broad spectrum of natural and synthetic stimuli. Those birds raised with their fathers tended to show behavioral evidence of song memorization but not of singing; thus auditory responses were not confounded by the birds' own vocalizations. In study 1, 37 of 158 neurons (23%) in 17 of 22 tutored and untutored birds were selective for only 1 of 10 stimuli comprising broadband signals, early juvenile songs and calls, female calls, and adult songs. Approximately 30% of the selective neurons (12/37 neurons in 9 birds) were selective for adult conspecific songs. All these were found in the song system nuclei HVC and paraHVC. Of 122 neurons (17 birds) in tutored birds, all of the conspecific song-selective neurons (8 neurons in 6 birds) were selective for the adult tutor song; none was selective for unfamiliar song. In study 2 with a different sampling strategy, we found that 11 of 12 song-selective neurons in 6 of 7 birds preferred the tutor song; none preferred unfamiliar or familiar conspecific songs. Most of these neurons were found in caudal lateral nidopallium (NCL) below HVC. Thus by the time a bird begins to sing, there are small numbers of tutor song-selective neurons distributed in several forebrain regions. We hypothesize that a small population of higher-order auditory neurons is innately selective for complex features of behaviorally relevant stimuli and these responses are modified by specific perceptual/social experience during development.

  13. The genome of a songbird

    DEFF Research Database (Denmark)

    Warren, Wesley C.; Clayton, David F.; Ellegren, Hans

    2010-01-01

    The zebra finch is an important model organism in several fields with unique relevance to human neuroscience. Like other songbirds, the zebra finch communicates through learned vocalizations, an ability otherwise documented only in humans and a few other animals and lacking in the chickenthe only...

  14. Compensation in resting metabolism for experimentally increased activity

    NARCIS (Netherlands)

    Deerenberg, C; Overkamp, GJF; Visser, GH; Daan, S; Heldmaier, G.

    1998-01-01

    To study zebra finch allocation of energy to day and night at two different workloads, we assessed the daily energy turnover from: (1) metabolizable energy of the food, and (2) doubly-labeled water. In both experiments we imposed two levels of activity on captive zebra finches (Taeniopygia guttata),

  15. Quantitative modelling of the biomechanics of the avian syrinx

    DEFF Research Database (Denmark)

    Elemans, Coen P. H.; Larsen, Ole Næsbye; Hoffmann, Marc R.

    2003-01-01

    We review current quantitative models of the biomechanics of bird sound production. A quantitative model of the vocal apparatus was proposed by Fletcher (1988). He represented the syrinx (i.e. the portions of the trachea and bronchi with labia and membranes) as a single membrane. This membrane acts...

  16. Zebra Stripes through the Eyes of Their Predators, Zebras, and Humans.

    Directory of Open Access Journals (Sweden)

    Amanda D Melin

    Full Text Available The century-old idea that stripes make zebras cryptic to large carnivores has never been examined systematically. We evaluated this hypothesis by passing digital images of zebras through species-specific spatial and colour filters to simulate their appearance for the visual systems of zebras' primary predators and zebras themselves. We also measured stripe widths and luminance contrast to estimate the maximum distances from which lions, spotted hyaenas, and zebras can resolve stripes. We found that beyond ca. 50 m (daylight and 30 m (twilight zebra stripes are difficult for the estimated visual systems of large carnivores to resolve, but not humans. On moonless nights, stripes are difficult for all species to resolve beyond ca. 9 m. In open treeless habitats where zebras spend most time, zebras are as clearly identified by the lion visual system as are similar-sized ungulates, suggesting that stripes cannot confer crypsis by disrupting the zebra's outline. Stripes confer a minor advantage over solid pelage in masking body shape in woodlands, but the effect is stronger for humans than for predators. Zebras appear to be less able than humans to resolve stripes although they are better than their chief predators. In conclusion, compared to the uniform pelage of other sympatric herbivores it appears highly unlikely that stripes are a form of anti-predator camouflage.

  17. In(-formations. The Meaning of Paratextual Elements in Debussy's Syrinx

    Directory of Open Access Journals (Sweden)

    Marcel Cobussen

    2005-12-01

    Full Text Available According to Gérard Genette, paratextual elements can be defined as that what comes against, beside, and in addition to the text (a score for example 'itself'. In that sense, they are always subordinate to 'their' text. The paratext is all material other than, though very closely connected to, the 'actual' text: the cover, the author's name, the title, preface, illustrations, notes, etc. It is therefore located in the space between inside and outside, the space between still belonging and not yet belonging to the text. This essay first of all investigates how paratextual elements (especially breath marks are necessary to provide a musical text (in this case Debussy's Syrinx for solo flute with a (temporary meaning and how they direct possible interpretations. Secondly, this essay also suggests that within the musical text 'itself', paratext is always already present (for example in ornamentation. However, in Syrinx, the borders between text and paratext are remarkably porous, creating a noteworthy questioning and shifting of hierarchies.

  18. Expression analysis of the speech-related genes FoxP1 and FoxP2 and their relation to singing behavior in two songbird species

    Science.gov (United States)

    Chen, Qianqian; Heston, Jonathan B.; Burkett, Zachary D.; White, Stephanie A.

    2013-01-01

    SUMMARY Humans and songbirds are among the rare animal groups that exhibit socially learned vocalizations: speech and song, respectively. These vocal-learning capacities share a reliance on audition and cortico-basal ganglia circuitry, as well as neurogenetic mechanisms. Notably, the transcription factors Forkhead box proteins 1 and 2 (FoxP1, FoxP2) exhibit similar expression patterns in the cortex and basal ganglia of humans and the zebra finch species of songbird, among other brain regions. Mutations in either gene are associated with language disorders in humans. Experimental knock-down of FoxP2 in the basal ganglia song control region Area X during song development leads to imprecise copying of tutor songs. Moreover, FoxP2 levels decrease naturally within Area X when zebra finches sing. Here, we examined neural expression patterns of FoxP1 and FoxP2 mRNA in adult Bengalese finches, a songbird species whose songs exhibit greater sequence complexity and increased reliance on audition for maintaining their quality. We found that FoxP1 and FoxP2 expression in Bengalese finches is similar to that in zebra finches, including strong mRNA signals for both factors in multiple song control nuclei and enhancement of FoxP1 in these regions relative to surrounding brain tissue. As with zebra finches, when Bengalese finches sing, FoxP2 is behaviorally downregulated within basal ganglia Area X over a similar time course, and expression negatively correlates with the amount of singing. This study confirms that in multiple songbird species, FoxP1 expression highlights song control regions, and regulation of FoxP2 is associated with motor control of song. PMID:24006346

  19. Genetic diversity of piroplasms in plains zebra (Equus quagga burchellii) and Cape mountain zebra (Equus zebra zebra) in South Africa.

    Science.gov (United States)

    Bhoora, Raksha; Buss, Peter; Guthrie, Alan J; Penzhorn, Barend L; Collins, Nicola E

    2010-11-24

    Seventy EDTA blood samples collected from plains zebra (Equus quagga burchellii) and Cape mountain zebra (Equus zebra zebra) were screened for the presence of piroplasm parasite DNA using quantitative T. equi-specific and B. caballi-specific TaqMan real-time PCR (qPCR) tests. T. equi parasite DNA was detected in 60 samples, 19 of which were also positive for B. caballi. Approximately 1480bp of the piroplasm 18S rRNA gene was amplified and sequenced from 17 samples, while the V4 hypervariable region of the 18S rRNA gene was amplified, cloned and sequenced from 31 samples. BLASTN analysis revealed that all of the sequences obtained were most similar to T. equi genotypes and not B. caballi genotypes. Although Babesia parasites were present in some of these samples, as indicated by qPCR, the parasitaemia may have been too low to allow detection by cloning of PCR products from a mixed infection. Sequence analyses of both the full-length and the V4 hypervariable region of the T. equi 18S rRNA gene revealed the existence of 13 new T. equi sequences from zebra, confirming the existence of sequence heterogeneity in the rRNA genes of the parasites that cause equine piroplasmosis, and further suggesting that there may be additional, as yet unidentified, T. equi and B. caballi 18S rRNA sequences present in the horse and zebra populations in South Africa. The occurrence of previously unrecognized sequence variation could pose a potential problem in the implementation of diagnostic tests targeting the 18S rRNA gene. Copyright © 2010 Elsevier B.V. All rights reserved.

  20. Effects of the social environment during adolescence on the development of social behaviour, hormones and morphology in male zebra finches (Taeniopygia guttata).

    Science.gov (United States)

    Bölting, Stefanie; von Engelhardt, Nikolaus

    2017-01-01

    Individual differences in behaviour are widespread in the animal kingdom and often influenced by the size or composition of the social group during early development. In many vertebrates the effects of social interactions early in life on adult behaviour are mediated by changes in maturation and physiology. Specifically, increases in androgens and glucocorticoids in response to social stimulation seem to play a prominent role in shaping behaviour during development. In addition to the prenatal and early postnatal phase, adolescence has more recently been identified as an important period during which adult behaviour and physiology are shaped by the social environment, which so far has been studied mostly in mammals. We raised zebra finches ( Taeniopygia guttata ) under three environmental conditions differing in social complexity during adolescence - juvenile pairs, juvenile groups, and mixed-age groups - and studied males' behavioural, endocrine, and morphological maturation, and later their adult behaviour. As expected, group-housed males exhibited higher frequencies of social interactions. Group housing also enhanced song during adolescence, plumage development, and the frequency and intensity of adult courtship and aggression. Some traits, however, were affected more in juvenile groups and others in mixed-age groups. Furthermore, a testosterone peak during late adolescence was suppressed in groups with adults. In contrast, corticosterone concentrations did not differ between rearing environments. Unexpectedly, adult courtship in a test situation was lowest in pair-reared males and aggression depended upon the treatment of the opponent with highest rates shown by group-reared males towards pair-reared males. This contrasts with previous findings, possibly due to differences in photoperiod and the acoustic environment. Our results support the idea that effects of the adolescent social environment on adult behaviour in vertebrates are mediated by changes in

  1. Species collapse via hybridization in Darwin's tree finches.

    Science.gov (United States)

    Kleindorfer, Sonia; O'Connor, Jody A; Dudaniec, Rachael Y; Myers, Steven A; Robertson, Jeremy; Sulloway, Frank J

    2014-03-01

    Species hybridization can lead to fitness costs, species collapse, and novel evolutionary trajectories in changing environments. Hybridization is predicted to be more common when environmental conditions change rapidly. Here, we test patterns of hybridization in three sympatric tree finch species (small tree finch Camarhynchus parvulus, medium tree finch Camarhynchus pauper, and large tree finch: Camarhynchus psittacula) that are currently recognized on Floreana Island, Galápagos Archipelago. Genetic analysis of microsatellite data from contemporary samples showed two genetic populations and one hybrid cluster in both 2005 and 2010; hybrid individuals were derived from genetic population 1 (small morph) and genetic population 2 (large morph). Females of the large and rare species were more likely to pair with males of the small common species. Finch populations differed in morphology in 1852-1906 compared with 2005/2010. An unsupervised clustering method showed (a) support for three morphological clusters in the historical tree finch sample (1852-1906), which is consistent with current species recognition; (b) support for two or three morphological clusters in 2005 with some (19%) hybridization; and (c) support for just two morphological clusters in 2010 with frequent (41%) hybridization. We discuss these findings in relation to species demarcations of Camarhynchus tree finches on Floreana Island.

  2. Ecoimmunity in Darwin's finches: invasive parasites trigger acquired immunity in the medium ground finch (Geospiza fortis.

    Directory of Open Access Journals (Sweden)

    Sarah K Huber

    Full Text Available BACKGROUND: Invasive parasites are a major threat to island populations of animals. Darwin's finches of the Galápagos Islands are under attack by introduced pox virus (Poxvirus avium and nest flies (Philornis downsi. We developed assays for parasite-specific antibody responses in Darwin's finches (Geospiza fortis, to test for relationships between adaptive immune responses to novel parasites and spatial-temporal variation in the occurrence of parasite pressure among G. fortis populations. METHODOLOGY/PRINCIPAL FINDINGS: We developed enzyme-linked immunosorbent assays (ELISAs for the presence of antibodies in the serum of Darwin's finches specific to pox virus or Philornis proteins. We compared antibody levels between bird populations with and without evidence of pox infection (visible lesions, and among birds sampled before nesting (prior to nest-fly exposure versus during nesting (with fly exposure. Birds from the Pox-positive population had higher levels of pox-binding antibodies. Philornis-binding antibody levels were higher in birds sampled during nesting. Female birds, which occupy the nest, had higher Philornis-binding antibody levels than males. The study was limited by an inability to confirm pox exposure independent of obvious lesions. However, the lasting effects of pox infection (e.g., scarring and lost digits were expected to be reliable indicators of prior pox infection. CONCLUSIONS/SIGNIFICANCE: This is the first demonstration, to our knowledge, of parasite-specific antibody responses to multiple classes of parasites in a wild population of birds. Darwin's finches initiated acquired immune responses to novel parasites. Our study has vital implications for invasion biology and ecological immunology. The adaptive immune response of Darwin's finches may help combat the negative effects of parasitism. Alternatively, the physiological cost of mounting such a response could outweigh any benefits, accelerating population decline. Tests

  3. Carotenoid accumulation in the tissues of zebra finches: predictors of integumentary pigmentation and implications for carotenoid allocation strategies.

    Science.gov (United States)

    McGraw, Kevin J; Toomey, Matthew B

    2010-01-01

    Carotenoid pigments produce the bright yellow to red ornamental colors of many animals, especially birds, and must ultimately be derived from the diet. However, they are also valuable for many physiological functions (e.g., antioxidants, immunostimulants, photoprotection, visual tuning, yolk nourishment to embryos), and as a result they are present in numerous internal body tissues (e.g., liver, adipose tissue, retina) whose carotenoid types and amounts are rarely studied in the context of color acquisition. Because male and female animals typically place different priorities on fitness-enhancing activities (e.g., gametic investment in females, sexual attraction in males), carotenoid allocation may track such investment patterns in the two sexes, and we can test for such sex-specific priorities of carotenoids by assessing body-tissue distributions of these pigments. We used high-performance liquid chromatography to identify and quantify carotenoid pigments from the plasma, liver, adipose tissue, and retina as well as the beak and legs of male and female zebra finches (Taeniopygia guttata), a species in which males display sexually attractive, red, carotenoid-based beak coloration and females also display some (albeit a less rich orange) beak color. To our knowledge, this is the first study of the predictors of carotenoid-based leg coloration-another potentially important visual signal-in this species. The same suite of dietary (e.g., lutein, zeaxanthin, beta-cryptoxanthin) and metabolically derived (e.g., dehydrolutein, anhydrolutein) yellow and orange carotenoids was present in plasma, liver, and adipose tissue of both sexes. Retina contained two different metabolites (astaxanthin and galloxanthin) that serve specific functions in association with unique photoreceptor types in the eye. Beaks were enriched with four red ketocarotenoid derivatives in both sexes (alpha-doradexanthin, adonirubin, astaxanthin, and canthaxanthin), while the carotenoid profile of legs

  4. Uropygial gland volatiles may code for olfactory information about sex, individual, and species in Bengalese finches Lonchura striata

    Directory of Open Access Journals (Sweden)

    Jian-Xu ZHANG et al.

    2009-10-01

    Full Text Available Over-shadowed by eye-catching vocal and visual signals, chemical communication has long been overlooked in birds. This study aimed at exploring whether volatile composition of the uropygial gland secretion (UGS of birds was associated with the information about sex, individual and species. By using dichloromethane extraction and gas chromatography-mass spectrometry (GC-MS, we analyzed the UGS volatiles of domesticated Bengalese finches (Lonchura striata, Estrildiea which is also known as white-rumped munias. We characterized 16 volatile molecules from the UGS, including eight n-alkanols, five diesters, an ester, an aldehyde and a fatty acid, and quantified them in terms of GC peak area percentages (relative abundances. Among these compounds, hexadecanol and octadecanol were major components in both sexes. The former was richer in males than females and the latter richer in females than males, suggesting that they might be male and female pheromone candidates, respectively. The high inter-individual variations, in relative abundance, of the UGS volatiles implied that they might carry information about individuality. The similarity between GC profiles of the UGS and wing feather from same individuals indicates that the birds might preen the secretion to their feathers to transmit chemical cues. Additionally, by comparing with three sympatric passerine species,i.e., zebra finches Taeniopygia guttata, yellow-bowed buntings Emberiza chrysophrys and rooks Corvus frugilegus, we found that the composition of C13-C18 alkanols in the UGS might contain information about species. Our study also show that quantitative differences (degree of same UGS volatiles might be the key for the Bengalese finch to code for information about sex and individuality whereas both the kind and degree of UGS constituents could be utilized to code for information about species [Current Zoology 55 (5:–2009].

  5. Electrocardiography of Grevy's zebras (Equus grevyi).

    Science.gov (United States)

    Myers, Debbie A; Citino, Scott; Mitchell, Mark A

    2008-09-01

    Electrocardiograms (ECGs) are a good baseline test for assessing cardiac rhythm. ECGs have not been reported in any zebra species and in very few Perissodactyla species. Standard limb, six-lead ECGs were recorded in 23 anesthetized Grevy's zebras (Equus grevyi). Heart rate, RR interval, P-wave duration, RR maximum/minimum, PR interval, QRS duration, QT interval, ST segment deviation, P-wave amplitude, QRS amplitude, and T-wave amplitude were measured and calculated from lead II ECGs from these Grevy's zebras. Several variables were tested, including gender, age (0-24, 24-48, 48-180, and >180 mo), weight (350 kg), pregnancy status, and anesthetic differences (standard dose or supplemented dose), to see if they affected ECG values in these animals. There were no significant differences in any of the ECG parameters between genders. RR and QT intervals were longer in older zebras; heart rates were faster in younger zebras. The RR and PR intervals, as well as the QRS duration, were greater in heavier zebras; heart rates were faster in lighter zebras. The RR interval was significantly longer in pregnant zebras. There were no significant differences in any of the ECG parameters for zebras anesthetized with a standardized dose of the drug combination etorphine-detomidine-acepromazine compared to those receiving additional supplements of these drugs and/or ketamine. All other parameters were not significantly different among groups, except where noted previously. The results of this research indicate that differences in ECG parameters in zebras may occur between animals of different ages, weights, and pregnancy status and that these factors should be considered when interpreting the respective ECGs of these zebras.

  6. Cardiac evaluation of anesthetized Grevy's zebras (Equus grevyi).

    Science.gov (United States)

    Adin, Darcy B; Maisenbacher, Herbert W; Ojeda, Nyurka; Fiorello, Christine V; Estrada, Amara H; Prosek, Robert; Citino, Scott B

    2007-02-01

    To determine ECG and echocardiographic measurements in healthy anesthetized Grevy's zebras (Equus grevyi). 20 healthy zebras. Auscultation, base-apex ECG, and echocardiography were performed on anesthetized zebras. Low-grade systolic murmurs were detected in the left basilar region in 4 of 20 zebras. Evaluation of ECGs from 19 zebras revealed sinus rhythm with a predominantly negative QRS complex and a mean +/- SD heart rate of 67 +/- 10 beats/min. Echocardiograms of sufficient image quality were obtained for 16 zebras. Interventricular septal thickness in diastole, left ventricular chamber in diastole and systole, left atrial diameter, and left ventricular mass were significantly and moderately correlated with estimated body weight (r values ranged from 0.650 to 0.884). Detectable swirling of blood in the right and sometimes the left ventricles was detected in 9 of 16 zebras, whereas physiologic regurgitation of blood was detected for the aortic valve in 3 zebras, pulmonary valve in 2 zebras, mitral valve in 2 zebras, and tricuspid valve in 1 zebra. Results of this study provide reference information for use in the cardiac evaluation of anesthetized Grevy's zebras.

  7. Population genetic diversity and hybrid detection in captive zebras.

    Science.gov (United States)

    Ito, Hideyuki; Langenhorst, Tanya; Ogden, Rob; Inoue-Murayama, Miho

    2015-08-21

    Zebras are members of the horse family. There are three species of zebras: the plains zebra Equus quagga, the Grevy's zebra E. grevyi and the mountain zebra E. zebra. The Grevy's zebra and the mountain zebra are endangered, and hybridization between the Grevy's zebra and the plains zebra has been documented, leading to a requirement for conservation genetic management within and between the species. We characterized 28 microsatellite markers in Grevy's zebra and assessed cross-amplification in plains zebra and two of its subspecies, as well as mountain zebra. A range of standard indices were employed to examine population genetic diversity and hybrid populations between Grevy's and plains zebra were simulated to investigate subspecies and hybrid detection. Microsatellite marker polymorphism was conserved across species with sufficient variation to enable individual identification in all populations. Comparative diversity estimates indicated greater genetic variation in plains zebra and its subspecies than Grevy's zebra, despite potential ascertainment bias. Species and subspecies differentiation were clearly demonstrated and F1 and F2 hybrids were correctly identified. These findings provide insights into captive population genetic diversity in zebras and support the use of these markers for identifying hybrids, including the known hybrid issue in the endangered Grevy's zebra.

  8. Detection of Mycoplasma gallisepticum in House Finches ( Haemorhous mexicanus) from Arizona.

    Science.gov (United States)

    Staley, Molly; Bonneaud, Camille; McGraw, Kevin J; Vleck, Carol M; Hill, Geoffrey E

    2018-03-01

    In 1994, an endemic poultry pathogen, Mycoplasma gallisepticum (MG), was identified as the causative agent of a novel disease in house finches ( Haemorhous mexicanus). After an initial outbreak in Maryland, MG spread rapidly throughout eastern North American populations of house finches. Subsequently, MG spread slowly through the northern interior of North America and then into the Pacific Northwest, finally reaching California in 2006. Until 2009, there were no reports of MG in the southwestern United States east of California. In August 2011, after reports of house finches displaying conjunctivitis characteristic of MG infection in Arizona, we trapped house finches at bird feeders in central Arizona (Tempe) and southern Arizona (Tucson and Green Valley) to assay for MG infection. Upon capture, we noted whether birds exhibited conjunctivitis, and we collected choanal swabs to test for the presence of MG DNA using PCR. We detected MG in finches captured from Green Valley (in ∼12% of birds captured), but not in finches from Tucson or Tempe. Based on resampling of house finches at these sites in July 2014, we suggest that central Arizona finches likely remain unexposed to MG. We also suggest that low urban connectivity between arid habitats of southern and central Arizona or a reduction in the prevalence of MG after its initial arrival in Arizona may be limiting the spread of MG from south to north in Arizona. In addition, the observed conjunctivitis-like signs in house finches that were negative for MG by PCR may be caused primarily by avian pox virus.

  9. Parasitism of wild Gouldian finches (Erythrura gouldiae) by the air-sac mite Sternostoma tracheacolum.

    Science.gov (United States)

    Tidemann, S C; McOrist, S; Woinarski, J C; Freeland, W J

    1992-01-01

    Sixty-two percent of 26 wild caught Gouldian finches (Erythrura gouldiae) were infected with Sternostoma tracheacolum, a parasitic rhinonyssid mite. The intensity of infection was higher in adult finches than juveniles, and higher in juvenile females than juvenile males. Histopathological investigation of wild Gouldian Finches revealed bronchopneumonia and air sacculitis associated with mite infection. Although this mite may not have contributed to the decline of Gouldian finch populations in the wild during the past 20 yr, it may be suppressing the return of the finch to its former status.

  10. Mesotocin and nonapeptide receptors promote estrildid flocking behavior.

    Science.gov (United States)

    Goodson, James L; Schrock, Sara E; Klatt, James D; Kabelik, David; Kingsbury, Marcy A

    2009-08-14

    Proximate neural mechanisms that influence preferences for groups of a given size are almost wholly unknown. In the highly gregarious zebra finch (Estrildidae: Taeniopygia guttata), blockade of nonapeptide receptors by an oxytocin (OT) antagonist significantly reduced time spent with large groups and familiar social partners independent of time spent in social contact. Opposing effects were produced by central infusions of mesotocin (MT, avian homolog of OT). Most drug effects appeared to be female-specific. Across five estrildid finch species, species-typical group size correlates with nonapeptide receptor distributions in the lateral septum, and sociality in female zebra finches was reduced by OT antagonist infusions into the septum but not a control area. We propose that titration of sociality by MT represents a phylogenetically deep framework for the evolution of OT's female-specific roles in pair bonding and maternal functions.

  11. Attenuated Phenotype of a Recent House Finch-Associated Mycoplasma gallisepticum Isolate in Domestic Poultry.

    Science.gov (United States)

    Pflaum, K; Tulman, E R; Beaudet, J; Liao, X; Dhondt, K V; Dhondt, A A; Hawley, D M; Ley, D H; Kerr, K M; Geary, S J

    2017-06-01

    Mycoplasma gallisepticum , known primarily as a respiratory pathogen of domestic poultry, has emerged since 1994 as a significant pathogen of the house finch ( Haemorhous mexicanus ) causing severe conjunctivitis and mortality. House finch-associated M. gallisepticum (HFMG) spread rapidly and increased in virulence for the finch host in the eastern United States. In the current study, we assessed virulence in domestic poultry with two temporally distant, and yet geographically consistent, HFMG isolates which differ in virulence for house finches-Virginia 1994 (VA1994), the index isolate of the epidemic, and Virginia 2013 (VA2013), a recent isolate of increased house finch virulence. Here we report a significant difference between VA1994 and VA2013 in their levels of virulence for chickens; notably, this difference correlated inversely to the difference in their levels of virulence for house finches. VA1994, while moderately virulent in house finches, displayed significant virulence in the chicken respiratory tract. VA2013, while highly virulent in the house finch, was significantly attenuated in chickens relative to VA1994, displaying less-severe pathological lesions in, and reduced bacterial recovery from, the respiratory tract. Overall, these data indicate that a recent isolate of HFMG is greatly attenuated in the chicken host relative to the index isolate, notably demonstrating a virulence phenotype in chickens inversely related to that in the finch host. Copyright © 2017 American Society for Microbiology.

  12. Androgens regulate gene expression in avian skeletal muscles.

    Directory of Open Access Journals (Sweden)

    Matthew J Fuxjager

    Full Text Available Circulating androgens in adult reproductively active male vertebrates influence a diversity of organ systems and thus are considered costly. Recently, we obtained evidence that androgen receptors (AR are expressed in several skeletal muscles of three passeriform birds, the golden-collared manakin (Manacus vitellinus, zebra finch (Taenopygia guttata, and ochre-bellied flycatcher (Mionectes oleagieus. Because skeletal muscles that control wing movement make up the bulk of a bird's body mass, evidence for widespread effects of androgen action on these muscles would greatly expand the functional impact of androgens beyond their well-characterized effects on relatively discrete targets throughout the avian body. To investigate this issue, we use quantitative PCR (qPCR to determine if androgens alter gene mRNA expression patterns in wing musculature of wild golden-collared manakins and captive zebra finches. In manakins, the androgen testosterone (T up-regulated expression of parvalbumin (PV and insulin-like growth factor I (IGF-I, two genes whose products enhance cellular Ca(2+ cycling and hypertrophy of skeletal muscle fibers. In T-treated zebra finches, the anti-androgen flutamide blunted PV and IGF-I expression. These results suggest that certain transcriptional effects of androgen action via AR are conserved in passerine skeletal muscle tissue. When we examined wing muscles of manakins, zebra finches and ochre-bellied flycatchers, we found that expression of PV and IGF-I varied across species and in a manner consistent with a function for AR-dependent gene regulation. Together, these findings imply that androgens have the potential to act on avian muscle in a way that may enhance the physicality required for successful reproduction.

  13. ANDROID BASED TELEOPERATION FOR THE FINCH ROBOT

    Directory of Open Access Journals (Sweden)

    Oliver Faust

    2016-09-01

    Full Text Available The act of creating a robot involves systems engineering and creative problem solutions. It is about using established components to create a system that works in the natural or at least in the human environment. The current project is no exception, we have used the Robot Operating System (ROS to create an android based teleoperator application for the Finch robot. A Raspberry Pi processing platform establishes the link between the android device and the Finch robot. The most creative task, during the system design, was to translate the commands from the teleoperator application into wheel movements of the Finch robot. The translation must take into account the physical setup of the robot, including unintended negative influences, such as drag. The command translation involved a nonlinear coordinate transformation. The ROS framework enabled us to focus on that nonstandard coordinate translation task by offering a high level of abstraction and the ability to create component functionalities independently.

  14. In vivo detection of fluctuating brain steroid levels SHORT

    Science.gov (United States)

    Ikeda, Maaya; Rensel, Michelle A.; Schlinger, Barney A.; Remage-Healey, Luke

    2015-01-01

    This protocol describes a method for in vivo measurement of steroid hormones in brain circuits of the zebra finch. In vivo microdialysis has been used successfully to detect fluctuating neurosteroids in the auditory forebrain (Remage-Healey et al., 2008; 2012; Ikeda et al., 2012) and in the hippocampus (Rensel et al., 2012; 2013) of behaving adult zebra finches. In some cases, the steroids measured are derived locally (e.g., ‘neurosteroids’ like estrogens in males) whereas in other cases the steroids measured reflect systemic circulating levels and/or central conversion (e.g., the primary androgen testosterone and the primary glucocorticoid corticosterone). We also describe the method of reverse-microdialysis (‘retrodialysis’) of compounds that can influence local steroid neurochemistry as well as behavior. In vivo microdialysis can now be used to study steroid signaling in the brain for a variety of experimental purposes. Furthermore, similar methods have been developed to examine changing levels of catecholamines in behaving zebra finches (e.g., Sasaki et al., 2006). Thus, the combined study of neurochemistry and behavior in a vocal learning species now has a new set of powerful tools. PMID:25342066

  15. A SEROLOGIC AND POLYMERASE CHAIN REACTION SURVEY OF EQUINE HERPESVIRUS IN BURCHELL'S ZEBRAS (EQUUS QUAGGA), HARTMANN'S MOUNTAIN ZEBRAS (EQUUS ZEBRA HARTMANNAE), AND THOMSON'S GAZELLES (EUDORCAS THOMSONII) IN A MIXED SPECIES SAVANNAH EXHIBIT.

    Science.gov (United States)

    Lopez, Karen M; Fleming, Gregory J; Mylniczenko, Natalie D

    2016-12-01

    Reports of equine herpesvirus (EHV) 1 and EHV-9 causing clinical disease in a wide range of species have been well documented in the literature. It is thought that zebras are the natural hosts of EHV-9 both in the wild and in captive collections. Concerns about potential interspecies transmission of EHV-1 and EHV-9 in a mixed species savannah exhibit prompted serologic and polymerase chain reaction surveys. Eighteen Burchell's zebras ( Equus quagga ), 11 Hartmann's mountain zebras ( Equus zebra hartmannae), and 14 Thomson's gazelles ( Eudorcas thomsonii ) cohabitating the same exhibit were examined for EHV-1 virus neutralization titers, and evidence of virus via EHV 1-5 polymerase chain reactions. None of the animals had previous exposure to vaccination with EHV-1 or EHV-4. All tested zebras had positive EHV-1 titers, ranging from 4 to 384. All zebras and Thomson's gazelles had negative polymerase chain reaction results for all targeted equine herpesviruses. EHV-9-specific assays are not available but EHV-1, EHV-4, and EHV-9 cross-react serologically. Positive serology results indicate a potential latent equine herpesvirus in the zebra population, which prompted initiation of an equine herpesvirus vaccine protocol, changes in pregnant zebra mare management, and equine herpesvirus polymerase chain reaction screening prior to shipment to or from the study site.

  16. Environmental DNA mapping of Zebra Mussel populations

    Science.gov (United States)

    Amberg, Jon J.; Merkes, Christopher

    2016-01-01

    Environmental DNA (eDNA) has become a popular tool for detecting aquatic invasive species, but advancements have made it possible to potentially answer other questions like reproduction, movement, and abundance of the targeted organism. In this study we developed a Zebra Mussel (Dreissena polymorpha) eDNA protocol. We then determined if this assay could be used to help determine Zebra Mussel biomass in a lake with a well-established population of Zebra Mussels and a lake with an emerging population of mussels. Our eDNA assay detected DNA of Zebra Mussels but not DNA from more than 20 other species of fish and mussels, many commonly found in Minnesota waters. Our assay did not predict biomass. We did find that DNA from Zebra Mussels accumulated in softer substrates in both lakes, even though the mussels were predominately on the harder substrates. Therefore, we concluded that eDNA may be useful to detect the presence of Zebra Mussels in these lakes but our assay/approach could not predict biomass.

  17. Zebra mussel monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Hennagir, T.

    1994-01-01

    In less than a decade, zebra mussels have become the latest environmental scourge to plague the North American power industry. Infestations in the Great Lakes region have already reached natural disaster proportions. The invasion shows little sign of subsiding; Michigan's inland waters are the next most likely threatened area. In the southern United States, the mussles' migration has extended about 50 miles deeper than experts had originally predicted. By the year 2000, zebra mussel monitoring and control efforts will cost business and industry $5 billion, according to the federal Aquatic Nuisance Prevention and Control Act of 1990. Estimates of more than $1 million to control mussel fouling are projected for the Great Lakes area alone. While small independent hydropower stations are not as susceptible to zebra mussles as coal or nuclear facilities, there is cause for concern. Infestations can quickly foul hydropower plant components, hampering equipment operation and reducing facility efficiency. In extreme cases, leaving the mussels unchecked can result in stoplog gate flow blockage or false water level gauge readings. Advance prevention is often an effective first-line of defense against this troublesome, rapidly spreading and extremely prolific mollusk. Mussel monitoring efforts should begin a year in advance of when zebra mussels are expected to appear in a given location. Hydropower facility components that come into contact or rely exclusively on raw water are at greatest risk, as are other external components such as embayment walls, screens, trashracks and fish ladders.

  18. A sex-chromosome inversion causes strong overdominance for sperm traits that affect siring success

    Czech Academy of Sciences Publication Activity Database

    Knief, U.; Forstmeier, W.; Pei, Y.; Ihle, M.; Wang, D.; Martin, K.; Opatová, Pavlína; Albrechtová, Jana; Wittig, M.; Franke, A.; Albrecht, Tomáš; Kempenaers, B.

    2017-01-01

    Roč. 1, č. 8 (2017), s. 1177-1184 E-ISSN 2397-334X R&D Projects: GA ČR(CZ) GAP506/12/2472 Institutional support: RVO:68081766 Keywords : Finch Taeniopygia guttata * mixed-effects models * zebra finch * pericentric inversions * fitness consequences * genetic parameters Subject RIV: EG - Zoology OBOR OECD: Biology (theoretical, mathematical, thermal, cryobiology, biological rhythm), Evolutionary biology

  19. Invasive parasites, habitat change and heavy rainfall reduce breeding success in Darwin's finches.

    Science.gov (United States)

    Cimadom, Arno; Ulloa, Angel; Meidl, Patrick; Zöttl, Markus; Zöttl, Elisabet; Fessl, Birgit; Nemeth, Erwin; Dvorak, Michael; Cunninghame, Francesca; Tebbich, Sabine

    2014-01-01

    Invasive alien parasites and pathogens are a growing threat to biodiversity worldwide, which can contribute to the extinction of endemic species. On the Galápagos Islands, the invasive parasitic fly Philornis downsi poses a major threat to the endemic avifauna. Here, we investigated the influence of this parasite on the breeding success of two Darwin's finch species, the warbler finch (Certhidea olivacea) and the sympatric small tree finch (Camarhynchus parvulus), on Santa Cruz Island in 2010 and 2012. While the population of the small tree finch appeared to be stable, the warbler finch has experienced a dramatic decline in population size on Santa Cruz Island since 1997. We aimed to identify whether warbler finches are particularly vulnerable during different stages of the breeding cycle. Contrary to our prediction, breeding success was lower in the small tree finch than in the warbler finch. In both species P. downsi had a strong negative impact on breeding success and our data suggest that heavy rain events also lowered the fledging success. On the one hand parents might be less efficient in compensating their chicks' energy loss due to parasitism as they might be less efficient in foraging on days of heavy rain. On the other hand, intense rainfalls might lead to increased humidity and more rapid cooling of the nests. In the case of the warbler finch we found that the control of invasive plant species with herbicides had a significant additive negative impact on the breeding success. It is very likely that the availability of insects (i.e. food abundance)is lower in such controlled areas, as herbicide usage led to the removal of the entire understory. Predation seems to be a minor factor in brood loss.

  20. Invasive parasites, habitat change and heavy rainfall reduce breeding success in Darwin's finches.

    Directory of Open Access Journals (Sweden)

    Arno Cimadom

    Full Text Available Invasive alien parasites and pathogens are a growing threat to biodiversity worldwide, which can contribute to the extinction of endemic species. On the Galápagos Islands, the invasive parasitic fly Philornis downsi poses a major threat to the endemic avifauna. Here, we investigated the influence of this parasite on the breeding success of two Darwin's finch species, the warbler finch (Certhidea olivacea and the sympatric small tree finch (Camarhynchus parvulus, on Santa Cruz Island in 2010 and 2012. While the population of the small tree finch appeared to be stable, the warbler finch has experienced a dramatic decline in population size on Santa Cruz Island since 1997. We aimed to identify whether warbler finches are particularly vulnerable during different stages of the breeding cycle. Contrary to our prediction, breeding success was lower in the small tree finch than in the warbler finch. In both species P. downsi had a strong negative impact on breeding success and our data suggest that heavy rain events also lowered the fledging success. On the one hand parents might be less efficient in compensating their chicks' energy loss due to parasitism as they might be less efficient in foraging on days of heavy rain. On the other hand, intense rainfalls might lead to increased humidity and more rapid cooling of the nests. In the case of the warbler finch we found that the control of invasive plant species with herbicides had a significant additive negative impact on the breeding success. It is very likely that the availability of insects (i.e. food abundanceis lower in such controlled areas, as herbicide usage led to the removal of the entire understory. Predation seems to be a minor factor in brood loss.

  1. Io, Argus, Hermes, Syrinx: An Example of the In_uence Excersiced by Ovid’s Metamorphoses on Ancient Roman Painting

    Directory of Open Access Journals (Sweden)

    Monika Osvald

    2012-07-01

    Full Text Available Although a main source of iconography ever since the Middle Ages, the influence of Ovid’s Metamorphoses on Ancient Roman visual arts has been presupposed rather than researched in detail. This lacuna in ancient iconography has been filled by the research project MetaMArS, Le Metamorfosi di Ovidio: Mito, Arte, Società, headed by Professor Francesca Ghedini of Padua University. The aim of the project is the systematic study of mutual influences between Ovid and the art of the Roman period. The research is based on a four-step methodology: (1 selecting the subject-matter and compiling an inventory of all literary and iconographic testimonies relating to it; (2 dividing Ovid’s narrative into episodes, i.e. acts and scenes; (3 classifying the iconographic repertoire by themes and schemes; (4 identifying the convergences/ divergences between the two parallel series. Following the above methodology, the paper focuses on the myth of Io woven by Ovid into Book 1 of the Metamorphoses (ll. 568–750. The lines have been divided into a prologue and five acts, with each of the latter subdivided into two scenes, while Act 4 subsumes the passage on Pan and Syrinx as well. In the opinion of Franz Bömer, it is the Syrinx element that is Ovid’s original contribution: thus both the Syrinx figure and the entire first scene of Act 4, which has Hermes in a shepherd’s attire beguile Argus by playing a new instrument, are crucial to establishing a potential in_uence of the Metamorphoses on select Roman iconography. The iconographic theme of Io, Argus, and Hermes is represented in Roman wall painting by eleven pictures, which may be divided into bi-figural and three-figural depictions, with the former corresponding to Act 3, Scene 1, and the latter to Act 4, Scene 1. In terms of composition, the images follow four schemes, the second of which includes two variants. Schemes 3 (in the House of the Citharist at Pompeii and 4 (in the temple of Isis at Pompeii

  2. Nest destruction elicits indiscriminate con- versus heterospecific brood parasitism in a captive bird.

    Science.gov (United States)

    Shaw, Rachael C; Feeney, William E; Hauber, Mark E

    2014-12-01

    Following nest destruction, the laying of physiologically committed eggs (eggs that are ovulated, yolked, and making their way through the oviduct) in the nests of other birds is considered a viable pathway for the evolution of obligate interspecific brood parasitism. While intraspecific brood parasitism in response to nest predation has been experimentally demonstrated, this pathway has yet to be evaluated in an interspecific context. We studied patterns of egg laying following experimental nest destruction in captive zebra finches, Taeniopygia guttata, a frequent intraspecific brood parasite. We found that zebra finches laid physiologically committed eggs indiscriminately between nests containing conspecific eggs and nests containing heterospecific eggs (of Bengalese finches, Lonchura striata vars. domestica), despite the con- and heterospecific eggs differing in both size and coloration. This is the first experimental evidence that nest destruction may provide a pathway for the evolution of interspecific brood parasitism in birds.

  3. Zebra: searching for rare diseases

    DEFF Research Database (Denmark)

    Dragusin, Radu; Petcu, Paula; Lioma, Christina

    2012-01-01

    disease diagnostic hypotheses in the domain of medical IR. In this work, we build upon an existing vertical medical search engine, Zebra, that is focused on rare disease diagnosis. In previous work, Zebra has been evaluated using real-life medical cases of rare and difficult diseases, and has been found...

  4. Placentation in the plains zebra (Equus quagga).

    Science.gov (United States)

    Allen, W R Twink; Stansfield, Fiona; Wilsher, Sandra

    2017-10-01

    The placenta and fetal gonads of 12 pregnant plains zebra (Equus quagga), estimated to be between 81 and 239 days of gestation, were examined. The diffuse, microcotyledonary zebra placenta appeared, developmentally, to be 3-4 weeks behind its counterpart in horse pregnancy and this, together with the presence of small and long-lived endometrial cups, low levels of zebra chorionic gonadotrophin in maternal serum and few accessory corpora lutea in the maternal ovaries during the first half of gestation, made zebra pregnancy more similar to donkey than horse pregnancy. Zebra fetal gonads enlarged after 80 days of gestation and their interstitial cells stained positively for 3β hydroxysteroid dehydrogenase and 17,20 lyase steroid enzymes while the trophoblast stained for aromatase. This confirmed that zebra fetal gonads, like those of the horse and donkey, can synthesise C19 androgens, which can then be aromatised by the placenta to C18 oestrogens. It is remarkable that such unusual feto-placental mechanisms of production of gonadotrophic and steroid hormones has persisted unchanged within the genus Equus despite the many physical adaptations and the considerable loss of chromosomes that have occurred during the evolution of its member species.

  5. Zebra: A striped network file system

    Science.gov (United States)

    Hartman, John H.; Ousterhout, John K.

    1992-01-01

    The design of Zebra, a striped network file system, is presented. Zebra applies ideas from log-structured file system (LFS) and RAID research to network file systems, resulting in a network file system that has scalable performance, uses its servers efficiently even when its applications are using small files, and provides high availability. Zebra stripes file data across multiple servers, so that the file transfer rate is not limited by the performance of a single server. High availability is achieved by maintaining parity information for the file system. If a server fails its contents can be reconstructed using the contents of the remaining servers and the parity information. Zebra differs from existing striped file systems in the way it stripes file data: Zebra does not stripe on a per-file basis; instead it stripes the stream of bytes written by each client. Clients write to the servers in units called stripe fragments, which are analogous to segments in an LFS. Stripe fragments contain file blocks that were written recently, without regard to which file they belong. This method of striping has numerous advantages over per-file striping, including increased server efficiency, efficient parity computation, and elimination of parity update.

  6. Zebra Mussels Pose a Threat to Virginia's Waters

    OpenAIRE

    Helfrich, Louis A. (Louis Anthony), 1942-; Weigmann, Diana L.; Speenburgh, Renee M.; Neves, Richard J.; Kitchel, Lisie; Bruenderman, Sue A., 1962-

    2005-01-01

    Provides an brief introduction to the invasion of the zebra mussel into American waters, explains the economic consequences they pose, and discusses if Virginia will inherit the problem, what the public can do to help, the general lifecycle of the zebra mussel and if they can be controlled, and who is working on the zebra mussel problem.

  7. Opposing effects of oxidative challenge and carotenoids on antioxidant status and condition-dependent sexual signalling

    Czech Academy of Sciences Publication Activity Database

    Tomášek, Oldřich; Gabrielová, B.; Kačer, P.; Maršík, Petr; Svobodová, J.; Syslová, K.; Vinkler, M.; Albrecht, Tomáš

    2016-01-01

    Roč. 6, č. 23546 (2016), s. 23546 ISSN 2045-2322 R&D Projects: GA ČR(CZ) GAP506/12/2472; GA ČR GA15-11782S Institutional support: RVO:68081766 ; RVO:61389030 Keywords : finch Taenopygia guttata * plumage coloration * in-vivo * information content * immune activation * zebra finches * life span * stress * expression * capacity Subject RIV: EG - Zoology Impact factor: 4.259, year: 2016

  8. Forecasting the expansion of zebra mussels in the United States.

    Science.gov (United States)

    Bossenbroek, Jonathan M; Johnson, Ladd E; Peters, Brett; Lodge, David M

    2007-06-01

    Because zebra mussels spread rapidly throughout the eastern United States in the late 1980s and early 1990s, their spread to the western United States has been expected. Overland dispersal into inland lakes and reservoirs, however, has occurred at a much slower rate than earlier spread via connected, navigable waterways. We forecasted the potential western spread of zebra mussels by predicting the overland movement of recreational boaters with a production-constrained gravity model. We also predicted the potential abundance of zebra mussels in two western reservoirs by comparing their water chemistry characteristics with those of water bodies with known abundances of zebra mussels. Most boats coming from waters infested with zebra mussels were taken to areas that already had zebra mussels, but a small proportion of such boats did travel west of the 100th meridian. If zebra mussels do establish in western U.S. water bodies, we predict that population densities could achieve similar levels to those in the Midwestern United States, where zebra mussels have caused considerable economic and ecological impacts. Our analyses suggest that the dispersal of zebra mussels to the western United States is an event of low probability but potentially high impact on native biodiversity and human infrastructure. Combining these results with economic analyses could help determine appropriate investment levels in prevention and control strategies.

  9. CA/CPS: A Communications ZEBRA implementation using CPS

    International Nuclear Information System (INIS)

    Roberts, L.A.

    1991-05-01

    CZ/CPS is an implementation of the Communications ZEBRA distributed computing environment utilizing the CPS communications protocol. CZ/CPS is intended for parallelization of high energy physics application programs using the CERN Program Library memory and data structure management features. CZ/CPS provides transparent communication of ZEBRA data structures among cooperative processes using standard interfaces for ZEBRA I/O. Examples of usage in a CPS HBOOK4 and GEANT3 application are provided

  10. Personality is Tightly Coupled to Vasopressin-Oxytocin Neuron Activity in a Gregarious Finch

    Directory of Open Access Journals (Sweden)

    Aubrey M Kelly

    2014-02-01

    Full Text Available Nonapeptides of the vasopressin-oxytocin family modulate social processes differentially in relation to sex, species, behavioral phenotype, and human personality. However, the mechanistic bases for these differences are not well understood, in part because multidimensional personality structures remain to be described for common laboratory animals. Based upon principal components (PC analysis of extensive behavioral measures in social and nonsocial contexts, we now describe three complex dimensions of phenotype (personality for the zebra finch, a species that exhibits a human-like social organization that is based upon biparental nuclear families embedded within larger social groups. These dimensions can be characterized as Social competence/dominance, Gregariousness, and Anxiety. We further demonstrate that the phasic Fos response of nonapeptide neurons in the paraventricular nucleus of the hypothalamus and medial bed nucleus of the stria terminalis are significantly predicted by personality, sex, social context, and their interactions. Furthermore the behavioral PCs are each associated with a distinct suite of neural PCs that incorporate both peptide cell numbers and their phasic Fos responses, indicating that personality is reflected in complex patterns of neuromodulation arising from multiple peptide cell groups. These findings provide novel insights into the mechanisms underlying sex- and phenotype-specific modulation of behavior, and should be broadly relevant, given that vasopressin-oxytocin systems are strongly conserved across vertebrates.

  11. EPRI's zebra mussel monitoring and control guidelines

    International Nuclear Information System (INIS)

    Mussalli, Y.G.; Armor, A.; Edwards, R.; Mattice, J.; Miller, M.; Nott, B.; Tsou, J.L.

    1992-01-01

    The Electric Power Research Institute (EPRI) Zebra Mussel Monitoring and Control Guidelines is a comprehensive compilation of US and European practices. The zebra mussel has infested all the Great Lakes and is positioned to spread to the adjoining river basins. The impact of the zebra mussel on power plants is as a biofouler clogging water systems and heat exchangers. The EPRI guidelines discuss the distribution of the zebra mussel in the US, identification of the zebra mussel, potential threats to power plants, and methods to initiate the monitoring and control program. Both preventive and corrective measures are presented. Preventive measures include various monitoring methods to initiate control techniques. The control techniques include both chemical and nonchemical together with combining techniques. Corrective methods include operational considerations, chemical cleaning, and mechanical/physical cleaning. It may also be possible to incorporate design changes, such as open to closed-loop backfit, backflushing, or pretreatment for closed systems. Table 1 shows a matrix of the monitoring methods. Table 2 presents a control matrix related to nuclear, fossil, and hydro raw water systems. Table 3 is a summary of the applicability of treatments to the various raw water systems. Appendixes are included that contain specifications to aid utilities in implementing several of the control technologies

  12. Differing House Finch Cytokine Expression Responses to Original and Evolved Isolates of Mycoplasma gallisepticum.

    Science.gov (United States)

    Vinkler, Michal; Leon, Ariel E; Kirkpatrick, Laila; Dalloul, Rami A; Hawley, Dana M

    2018-01-01

    The recent emergence of the poultry bacterial pathogen Mycoplasma gallisepticum (MG) in free-living house finches ( Haemorhous mexicanus ), which causes mycoplasmal conjunctivitis in this passerine bird species, resulted in a rapid coevolutionary arms-race between MG and its novel avian host. Despite extensive research on the ecological and evolutionary dynamics of this host-pathogen system over the past two decades, the immunological responses of house finches to MG infection remain poorly understood. We developed seven new probe-based one-step quantitative reverse transcription polymerase chain reaction assays to investigate mRNA expression of house finch cytokine genes ( IL1B, IL6, IL10, IL18, TGFB2, TNFSF15 , and CXCLi2 , syn. IL8L ). These assays were then used to describe cytokine transcription profiles in a panel of 15 house finch tissues collected at three distinct time points during MG infection. Based on initial screening that indicated strong pro-inflammatory cytokine expression during MG infection at the periorbital sites in particular, we selected two key house finch tissues for further characterization: the nictitating membrane, i.e., the internal eyelid in direct contact with MG, and the Harderian gland, the secondary lymphoid tissue responsible for regulation of periorbital immunity. We characterized cytokine responses in these two tissues for 60 house finches experimentally inoculated either with media alone (sham) or one of two MG isolates: the earliest known pathogen isolate from house finches (VA1994) or an evolutionarily more derived isolate collected in 2006 (NC2006), which is known to be more virulent. We show that the more derived and virulent isolate NC2006, relative to VA1994, triggers stronger local inflammatory cytokine signaling, with peak cytokine expression generally occurring 3-6 days following MG inoculation. We also found that the extent of pro-inflammatory interleukin 1 beta signaling was correlated with conjunctival MG loads

  13. Differing House Finch Cytokine Expression Responses to Original and Evolved Isolates of Mycoplasma gallisepticum

    Directory of Open Access Journals (Sweden)

    Michal Vinkler

    2018-01-01

    Full Text Available The recent emergence of the poultry bacterial pathogen Mycoplasma gallisepticum (MG in free-living house finches (Haemorhous mexicanus, which causes mycoplasmal conjunctivitis in this passerine bird species, resulted in a rapid coevolutionary arms-race between MG and its novel avian host. Despite extensive research on the ecological and evolutionary dynamics of this host–pathogen system over the past two decades, the immunological responses of house finches to MG infection remain poorly understood. We developed seven new probe-based one-step quantitative reverse transcription polymerase chain reaction assays to investigate mRNA expression of house finch cytokine genes (IL1B, IL6, IL10, IL18, TGFB2, TNFSF15, and CXCLi2, syn. IL8L. These assays were then used to describe cytokine transcription profiles in a panel of 15 house finch tissues collected at three distinct time points during MG infection. Based on initial screening that indicated strong pro-inflammatory cytokine expression during MG infection at the periorbital sites in particular, we selected two key house finch tissues for further characterization: the nictitating membrane, i.e., the internal eyelid in direct contact with MG, and the Harderian gland, the secondary lymphoid tissue responsible for regulation of periorbital immunity. We characterized cytokine responses in these two tissues for 60 house finches experimentally inoculated either with media alone (sham or one of two MG isolates: the earliest known pathogen isolate from house finches (VA1994 or an evolutionarily more derived isolate collected in 2006 (NC2006, which is known to be more virulent. We show that the more derived and virulent isolate NC2006, relative to VA1994, triggers stronger local inflammatory cytokine signaling, with peak cytokine expression generally occurring 3–6 days following MG inoculation. We also found that the extent of pro-inflammatory interleukin 1 beta signaling was correlated with conjunctival

  14. A sensorimotor area in the songbird brain is required for production of vocalizations in the song learning period of development.

    Science.gov (United States)

    Piristine, Hande C; Choetso, Tenzin; Gobes, Sharon M H

    2016-11-01

    Sensory feedback is essential for acquiring and maintaining complex motor behaviors, including birdsong. In zebra finches, auditory feedback reaches the song control circuits primarily through the nucleus interfacialis nidopalii (Nif), which provides excitatory input to HVC (proper name)-a premotor region essential for the production of learned vocalizations. Despite being one of the major inputs to the song control pathway, the role of Nif in generating vocalizations is not well understood. To address this, we transiently inactivated Nif in late juvenile zebra finches. Upon Nif inactivation (in both hemispheres or on one side only), birds went from singing stereotyped zebra finch song to uttering highly variable and unstructured vocalizations resembling sub-song, an early juvenile song form driven by a basal ganglia circuit. Simultaneously inactivating Nif and LMAN (lateral magnocellular nucleus of the anterior nidopallium), the output nucleus of a basal ganglia circuit, inhibited song production altogether. These results suggest that Nif is required for generating the premotor drive for song. Permanent Nif lesions, in contrast, have only transient effects on vocal production, with song recovering within a day. The sensorimotor nucleus Nif thus produces a premotor drive to the motor pathway that is acutely required for generating learned vocalizations, but once permanently removed, the song system can compensate for its absence. © 2016 Wiley Periodicals, Inc. Develop Neurobiol 76: 1213-1225, 2016. © 2016 Wiley Periodicals, Inc.

  15. USGS Zebra Mussel Monitoring Program for north Texas

    Science.gov (United States)

    Churchill, Christopher J.; Baldys, Stanley

    2012-01-01

    The U.S. Geological Survey (USGS) Zebra Mussel Monitoring Program for north Texas provides early detection and monitoring of zebra mussels (Dreissena polymorpha) by using a holistic suite of detection methods. The program is designed to assess zebra mussel occurrence, distribution, and densities in north Texas waters by using four approaches: (1) SCUBA diving, (2) water-sample collection with plankton tow nets (followed by laboratory analyses), (3) artificial substrates, and (4) water-quality sampling. Data collected during this type of monitoring can assist rapid response efforts and can be used to quantify the economic and ecological effects of zebra mussels in the north Texas area. Monitoring under this program began in April 2010. The presence of large zebra mussel populations often causes undesirable economic and ecological effects, including damage to water-processing infrastructure and hydroelectric powerplants (with an estimated 10-year cost of $3.1 billion), displacement of native mussels, increases in concentrations of certain species of cyanobacteria, and increases in concentrations of geosmin (an organic compound that results in taste and odor issues in water). Since no large-scale, environmentally safe eradication method has been developed for zebra mussels, it is difficult to remove established populations. Broad physicochemical adaptability, prolific reproductive capacity, and rapid dispersal methods have enabled zebra mussels, within a period of about 20 years, to establish populations under differing environmental conditions across much of the eastern part of the United States. In Texas, the presence of zebra mussels was first confirmed in April 2009 in Lake Texoma in the Red River Basin along the Texas-Oklahoma border. They were most likely introduced into Lake Texoma through overland transport from an infested water body. Since then, the presence of zebra mussels has been reported in both the Red River and Washita River arms of Lake Texoma, in

  16. Neuroinflammation induces glial aromatase expression in the uninjured songbird brain

    Directory of Open Access Journals (Sweden)

    Saldanha Colin J

    2011-07-01

    Full Text Available Abstract Background Estrogens from peripheral sources as well as central aromatization are neuroprotective in the vertebrate brain. Under normal conditions, aromatase is only expressed in neurons, however following anoxic/ischemic or mechanical brain injury; aromatase is also found in astroglia. This increased glial aromatization and the consequent estrogen synthesis is neuroprotective and may promote neuronal survival and repair. While the effects of estradiol on neuroprotection are well studied, what induces glial aromatase expression remains unknown. Methods Adult male zebra finches (Taeniopygia guttata were given a penetrating injury to the entopallium. At several timepoints later, expression of aromatase, IL-1β-like, and IL-6-like were examined using immunohisotchemistry. A second set of zebra birds were exposed to phytohemagglutinin (PHA, an inflammatory agent, directly on the dorsal surface of the telencephalon without creating a penetrating injury. Expression of aromatase, IL-1β-like, and IL-6-like were examined using both quantitative real-time polymerase chain reaction to examine mRNA expression and immunohistochemistry to determine cellular expression. Statistical significance was determined using t-test or one-way analysis of variance followed by the Tukey Kramers post hoc test. Results Following injury in the zebra finch brain, cytokine expression occurs prior to aromatase expression. This temporal pattern suggests that cytokines may induce aromatase expression in the damaged zebra finch brain. Furthermore, evoking a neuroinflammatory response characterized by an increase in cytokine expression in the uninjured brain is sufficient to induce glial aromatase expression. Conclusions These studies are among the first to examine a neuroinflammatory response in the songbird brain following mechanical brain injury and to describe a novel neuroimmune signal to initiate aromatase expression in glia.

  17. Control of zebra mussels with ultraviolet radiation

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, D.P.

    1998-07-01

    This paper presents the results of research on the effects of low and medium pressure ultraviolet (UV) radiation on zebra mussel mortality carried out between 1992 and 1995. An initial 1992 study, carried out by Aquatic Sciences (ASI), showed that flow-through UV systems have the ability to kill zebra mussels and prevent them from attaching to downstream surfaces. However, this work did not include expanded testing to determine the limitations of UV radiation at higher flow rates or to further define effective working parameters. The 1994 study was carried out at the Lennox Thermal Generating Station (TGS) of Ontario Hydro in Kingston, Ontario. This study involved the testing of two open channel UV systems (medium and low pressure) in an effort to determine flow rates and volumes for which UV disinfection would be effective and practical for the prevention of zebra mussel infestation. It was recommended that medium pressure (MP) and low pressure (LP) UV systems be tested for their ability to control downstream settlement of zebra mussels, in flow-through trials.

  18. Zebra mussel filtration and its potential uses in industrial water treatment.

    Science.gov (United States)

    Elliott, Paul; Aldridge, David C; Moggridge, Geoff D

    2008-03-01

    The zebra mussel (Dreissena polymorpha) is a notorious freshwater biofouling pest, and populations of the species can alter aquatic environments through their substantial filtration capabilities. Despite the ecological importance of zebra mussel filtration, many predictions of their large-scale effects on ecosystems rely on extrapolations from filtration rates obtained in static laboratory experiments, not accounting for natural mussel densities, boundary layer effects, flow rates or elevated algal concentrations. This study used large-scale industrial flume trials to investigate the influence of these factors on zebra mussel filtration and proposes some novel industrial applications of these findings. The flume trials revealed some of the highest zebra mussel clearance rates found to date, up to 574+/-20mlh(-1)g(-1) of wet tissue mass. Under low algal concentrations, chlorophyll a removal by zebra mussels was not proportional to mussel density, indicating that field rates of zebra mussel grazing may be much lower than previous studies have predicted. Increasing ambient velocities up to 100mls(-1) ( approximately 4cms(-1)) led to increased clearance rates by zebra mussels, possibly due to the replenishment of locally depleted resources, but higher velocities of 300mls(-1) (12cms(-1)) did not lead to further significant increases in clearance rate. When additional algal cultures were dosed into the flumes, chlorophyll a removal increased approximately logarithmically with zebra mussel density and there were no differences in the clearance of three different species of alga: Ankyra judayi, Pandorina morum and Cyclotella meneghinia. Some novel industrial uses of these zebra mussel filtration studies are proposed, such as: (1) helping to inform models that predict the large-scale grazing effects of the mussels, (2) allowing estimates of zebra mussel densities in industrial pipelines, and (3) constructing large-scale biofilters for use in water clarification.

  19. FindZebra: a search engine for rare diseases.

    Science.gov (United States)

    Dragusin, Radu; Petcu, Paula; Lioma, Christina; Larsen, Birger; Jørgensen, Henrik L; Cox, Ingemar J; Hansen, Lars Kai; Ingwersen, Peter; Winther, Ole

    2013-06-01

    The web has become a primary information resource about illnesses and treatments for both medical and non-medical users. Standard web search is by far the most common interface to this information. It is therefore of interest to find out how well web search engines work for diagnostic queries and what factors contribute to successes and failures. Among diseases, rare (or orphan) diseases represent an especially challenging and thus interesting class to diagnose as each is rare, diverse in symptoms and usually has scattered resources associated with it. We design an evaluation approach for web search engines for rare disease diagnosis which includes 56 real life diagnostic cases, performance measures, information resources and guidelines for customising Google Search to this task. In addition, we introduce FindZebra, a specialized (vertical) rare disease search engine. FindZebra is powered by open source search technology and uses curated freely available online medical information. FindZebra outperforms Google Search in both default set-up and customised to the resources used by FindZebra. We extend FindZebra with specialized functionalities exploiting medical ontological information and UMLS medical concepts to demonstrate different ways of displaying the retrieved results to medical experts. Our results indicate that a specialized search engine can improve the diagnostic quality without compromising the ease of use of the currently widely popular standard web search. The proposed evaluation approach can be valuable for future development and benchmarking. The FindZebra search engine is available at http://www.findzebra.com/. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  20. Improved axial resolution of FINCH fluorescence microscopy when combined with spinning disk confocal microscopy.

    Science.gov (United States)

    Siegel, Nisan; Brooker, Gary

    2014-09-22

    FINCH holographic fluorescence microscopy creates super-resolved images with enhanced depth of focus. Addition of a Nipkow disk real-time confocal image scanner is shown to reduce the FINCH depth of focus while improving transverse confocal resolution in a combined method called "CINCH".

  1. Copper and copper-nickel alloys as zebra mussel antifoulants

    Energy Technology Data Exchange (ETDEWEB)

    Dormon, J.M.; Cottrell, C.M.; Allen, D.G.; Ackerman, J.D.; Spelt, J.K. [Univ. of Toronto, Ontario (Canada)

    1996-04-01

    Copper has been used in the marine environment for decades as cladding on ships and pipes to prevent biofouling by marine mussels (Mytilus edulis L.). This motivated the present investigation into the possibility of using copper to prevent biofouling in freshwater by both zebra mussels and quagga mussels (Dreissena polymorpha and D. bugensis collectively referred to as zebra mussels). Copper and copper alloy sheet proved to be highly effective in preventing biofouling by zebra mussels over a three-year period. Further studies were conducted with copper and copper-nickel mesh (lattice of expanded metal) and screen (woven wire with a smaller hole size), which reduced the amount of copper used. Copper screen was also found to be strongly biofouling-resistant with respect to zebra mussels, while copper mesh reduced zebra mussel biofouling in comparison to controls, but did not prevent it entirely. Preliminary investigations into the mechanism of copper antifouling, using galvanic couples, indicated that the release of copper ions from the surface of the exposed metal into the surrounding water is directly or indirectly responsible for the biofouling resistance of copper.

  2. Mitigation of unionid mortality caused by zebra mussel infestation: cleaning of unionids

    Science.gov (United States)

    Schloesser, Don W.

    1996-01-01

    Exotic zebra mussels Dreissena polymorpha have infested and caused mortality of native unionids in the Great Lakes since 1986; no other such parasitism of native unionids occurs in North America. Survival of unionids threatened by zebra mussel infestation was tested by suspending uncleaned and cleaned unionids in nearshore waters of western Lake Erie. Survival was determined, and newly settled zebra mussels were removed from clean unionids at eight intervals that ranged from 21 d to 77 d between 5 July 1990 and 3 July 1991. After 1 year, survival rates of uncleaned and cleaned unionids were 0% and 42%, respectively. Of the 10 species examined, only indivduals from 3 species (Amblema plicata plicata, Fusconaia flava, and Quadrula quadrula) survived 1 year. These species have relatively thick shells, which may have contributed to their survival. Removal of newly settled zebra mussels may be important to unionid survival because 98% of the zebra mussels removed after the initial cleaning were small mussels (zebra mussels cause mortality of unionids, but the removal of zebra mussels from unionids is the only method known that successfully reduces unionid mortality in waters colonized by zebra mussels.

  3. Research continues on zebra mussel control

    International Nuclear Information System (INIS)

    Anon.

    1993-01-01

    Researchers are working on many fronts to learn methods for controlling and combatting zebra mussels, a species of mussel that can attach to the inside of water intakes at hydroelectric and thermal power plants, and can reduce or block water flow. Biologists at the University of Toledo in Ohio report that compounds from the African soapberry plant called lemmatoxins are lethal to zebra mussels. In laboratory tests, researchers have determined 1 to 2 milligrams of purified lemmatoxins per liter will kill the mussels. In field tests, biologist Harold Lee flushed water through a mussel-infested pipe. He found that the berry extract killed mussels in four to eight hours, making continuous treatment of water intake pipes unnecessary, according to a report in New Scientists. The University of Toledo participated in another project, funded by the American Water Works Association Research Foundation. That project team included the cities of Toledo and Cleveland, Ohio, Finkbeiner, Pettis ampersand Strout, Ltd. consulting engineers, and researchers from Ohio's Case Western Reserve University. The team identified a chemical oxidant, sodium hypochlorite, as a cost-effective agent for controlling zebra mussels at water treatment plant intakes. Toledo has used the sodium hypochlorite and reports the chemical has cleared colonies of zebra mussels that had attached to the intake of its water treatment plant

  4. Zebra mussels invade Lake Erie muds

    Science.gov (United States)

    Berkman, Paul Arthur; Haltuch, Melissa A.; Tichich, Emily; Garton, David W.; Kennedy, Gregory W.; Gannon, John E.; Mackey, Scudder D.; Fuller, Jonathan A.; Liebenthal, Dale L.

    1998-01-01

    Zebra mussels (Dreissena polymorpha) originated in western Russia but have now become widespread in Europe and North America. They are widely known for their conspicuous invasion of rocks and other hard substrates in North American and European watersheds. We have found beds of zebra mussels directly colonizing sand and mud sediments each year across hundreds of square kilometres of North America's Lake Erie. This transformation of sedimentary habitats into mussel beds represents an unforeseen change in the invasive capacity of this species.

  5. Prevention of zebra mussel infestation and dispersal during aquaculture operations

    Science.gov (United States)

    Waller, D.L.; Fisher, S.W.; Dabrowska, H.

    1996-01-01

    The zebra mussel Dreissena polymorpha, an exotic invasive species, poses a major threat to North American fish management programs and the aquaculture industry. Fish hatcheries may become infected with zebra mussels from a variety of sources, including the water supply, fish shipments, boats, and equipment. The hatcheries could then serve as agents for the overland dispersal of zebra mussels into stocked waters and to other fish hatcheries. We evaluated the effectiveness and safety of aquaculture chemicals for use in controlling zebra mussels in fish hatcheries and preventing dispersal of veligers during fish transport. Chemicals were evaluated for use in fish transport and as disinfectants for ponds and equipment. Standardized static toxicity tests were conducted with representative species of warmwater, coolwater, and coldwater fishes and with larval (3-d-old veligers), early juvenile (settling larvae), and adult zebra mussels. Chemical concentrations and exposure durations were based on recommended treatment levels for fish, eggs, and ponds. Recommended treatment levels were also exceeded, if necessary, to establish lethal levels for zebra mussels of different developmental stages. Our results indicate that some chemicals currently in use in hatcheries may be effective for controlling zebra mussels in various operations. Chloride salts were the safest and most effective therapeutants tested for use in fish transport. The toxicity of chloride salts to fish varied among species and with temperature; only one treatment regime (sodium chloride at 10,000 mg/L) was safe to all fish species that we tested, but it was only effective on veliger and settler stages of the zebra mussel. Effective disinfectants were benzalkonium chloride for use on equipment and rotenone for use in ponds after fish are harvested. The regulatory status of the identified chemicals is discussed as well as several nonchemical control alternatives.

  6. Prevalence of blood parasites in eastern versus Western house finches: are eastern birds resistant to infection?

    Science.gov (United States)

    Davis, Andrew K; Hood, Wendy R; Hill, Geoffrey E

    2013-09-01

    The rapid spread of the bacterial disease, Mycoplasma gallisepticum (MG), throughout the introduced range of house finches (Carpodacus mexicanus) in eastern North America, compared to its slower spread through the native western range, has puzzled researchers and highlights the need to understand the relative differences in health state of finches from both populations. We conducted a light-microscope survey of hemoparasites in populations of finches from Arizona (within the western range) and from Alabama (within the eastern range), and compared our estimates of prevalence to published reports from house finches sampled in both ranges. Of the 33 Arizona birds examined, we recorded hematozoan infections in 16 (48.5%) individuals, compared to 1 infected Alabama bird out of 30 birds examined (3.3%). Based on independent surveys of seven western North American and five eastern North American populations of house finches the average prevalence of blood parasites in western populations is 38.8% (±17.9 SD), while the average prevalence within the eastern range is only 5.9% (±6.1 SD). The average rate of infection among all songbirds sampled in the east is 34.2% (±4.8 SD). Thus, our surveys of wild birds as well as previously published observations point to eastern house finches having a much lower prevalence of blood parasite infections than their western counterparts. Combined with the fact that eastern finches also tend to have lower rates of avian pox infections than do western birds (based on a literature review), these observations suggest that eastern birds have either strong resistance to these infections or high susceptibility and associated mortality.

  7. Does a Syrinx Matter for Return to Play in Contact Sports? A Case Report and Evidence-Based Review of Return-to-Play Criteria After Transient Quadriplegia.

    Science.gov (United States)

    Milles, Jeffrey L; Gallizzi, Michael A; Sherman, Seth L; Smith, Patrick A; Choma, Theodore J

    2014-09-01

    Transient quadriplegia is a rare injury that can change the course of an athlete's career if misdiagnosed or managed inappropriately. The clinician should be well versed in the return-to-play criteria for this type of injury. Unfortunately, when an unknown preexisting syrinx is present in the athlete, there is less guidance on their ability to return to play. This case report and review of the current literature illustrates a National Collegiate Athletic Association (NCAA) Division I football player who suffered a transient quadriplegic event during a kickoff return that subsequently was found to have an incidental cervical syrinx on magnetic resonance imaging. The player was able to have a full neurologic recovery, but ultimately he was withheld from football.

  8. Presumptive red maple (Acer rubrum) toxicosis in Grevy's zebra (Equus grevyi).

    Science.gov (United States)

    Weber, M; Miller, R E

    1997-03-01

    Two female Grevy's zebras (Equus grevyi), one juvenile and one adult, were treated for hemolytic anemia. The juvenile survived, but the adult animal, which also had methemoglobinemia, was euthanized after it failed to recover from anesthesia. Significant pathologic findings in the adult zebra included generalized icterus, hemoglobinuric nephrosis, and paracentral hepatic necrosis. Serum titers for known infectious causes of anemia were negative. Examination of the zebra holding areas revealed two hybrid red maple (Acer sp.) trees. There was no known exposure to other hemolytic agents. This is the first report of probable red maple-induced hemolysis in zebra.

  9. Birds and babies : a comparison of the early development in vocal learners

    NARCIS (Netherlands)

    Haar, Sita Minke ter

    2013-01-01

    This thesis provides a comparison of mostly perceptual development during vocal learning in songbirds (zebra finches) and human infants. The aim is to disentangle experience dependent and independent processes during vocal learning. In both human infants and juvenile songbirds, a perceptual

  10. Predation on exotic zebra mussels by native fishes: Effects on predator and prey

    Science.gov (United States)

    Magoulick, D.D.; Lewis, L.C.

    2002-01-01

    1. Exotic zebra mussels, Dreissena polymorpha, occur in southern U.S. waterways in high densities, but little is known about the interaction between native fish predators and zebra mussels. Previous studies have suggested that exotic zebra mussels are low profitability prey items and native vertebrate predators are unlikely to reduce zebra mussel densities. We tested these hypotheses by observing prey use of fishes, determining energy content of primary prey species of fishes, and conducting predator exclusion experiments in Lake Dardanelle, Arkansas. 2. Zebra mussels were the primary prey eaten by 52.9% of blue catfish, Ictalurus furcatus; 48.2% of freshwater drum, Aplodinotus grunniens; and 100% of adult redear sunfish, Lepomis microlophus. Blue catfish showed distinct seasonal prey shifts, feeding on zebra mussels in summer and shad, Dorosoma spp., during winter. Energy content (joules g-1) of blue catfish prey (threadfin shad, Dorosoma petenense; gizzard shad, D. cepedianum; zebra mussels; and asiatic clams, Corbicula fluminea) showed a significant species by season interaction, but shad were always significantly greater in energy content than bivalves examined as either ash-free dry mass or whole organism dry mass. Fish predators significantly reduced densities of large zebra mussels (>5 mm length) colonising clay tiles in the summers of 1997 and 1998, but predation effects on small zebra mussels (???5 mm length) were less clear. 3. Freshwater drum and redear sunfish process bivalve prey by crushing shells and obtain low amounts of higher-energy food (only the flesh), whereas blue catfish lack a shell-crushing apparatus and ingest large amounts of low-energy food per unit time (bivalves with their shells). Blue catfish appeared to select the abundant zebra mussel over the more energetically rich shad during summer, then shifted to shad during winter when shad experienced temperature-dependent stress and mortality. Native fish predators can suppress adult zebra

  11. Experimental demonstration of the fitness consequences of an introduced parasite of Darwin's finches.

    Directory of Open Access Journals (Sweden)

    Jennifer A H Koop

    2011-05-01

    Full Text Available Introduced parasites are a particular threat to small populations of hosts living on islands because extinction can occur before hosts have a chance to evolve effective defenses. An experimental approach in which parasite abundance is manipulated in the field can be the most informative means of assessing a parasite's impact on the host. The parasitic fly Philornis downsi, recently introduced to the Galápagos Islands, feeds on nestling Darwin's finches and other land birds. Several correlational studies, and one experimental study of mixed species over several years, reported that the flies reduce host fitness. Here we report the results of a larger scale experimental study of a single species at a single site over a single breeding season.We manipulated the abundance of flies in the nests of medium ground finches (Geospiza fortis and quantified the impact of the parasites on nestling growth and fledging success. We used nylon nest liners to reduce the number of parasites in 24 nests, leaving another 24 nests as controls. A significant reduction in mean parasite abundance led to a significant increase in the number of nests that successfully fledged young. Nestlings in parasite-reduced nests also tended to be larger prior to fledging.Our results confirm that P. downsi has significant negative effects on the fitness of medium ground finches, and they may pose a serious threat to other species of Darwin's finches. These data can help in the design of management plans for controlling P. downsi in Darwin's finch breeding populations.

  12. Co-existence of zebra mussels and freshwater unionids: Population dynamics of Leptodea fragilis in a coastal wetland infested with zebra mussels

    Science.gov (United States)

    Nichols, S. Jerrine; Amberg, Jon

    1999-01-01

    In 1996, thousands of live Leptodea fragilis were collected from a marsh located in the western basin of Lake Erie that was infested with zebra mussels (Dreissena polymorpha). Despite the presence of zebra mussels at this site for a number of years, this L. fragilis population showed no signs of competition-induced changes in population dynamics. Biofouling was limited: fewer than 1% of the L. fragilis showed evidence of recent or past zebra mussel colonization. Successful recruitment occurred yearly, with multiple year classes collected that ranged in age from 1 to 12 years. However, age and shell length were not well correlated. Seventy-one percent of the individuals collected were 51-80 mm long, but ranged in age from 2 to 4.5 years. Three different patterns of growth or shell deposition were found. Some individuals grew rapidly, reaching 105 mm in 3.5 years, while others grew only 4.5 mm over the same time period. A few grew poorly during some years but very rapidly in others. Individuals with a shell length of 41 mm or more were sexually mature and females were more common than males. The strong recruitment and steady growth of this population showed no change between the years before and after the zebra mussel invasion, indicating that this marsh is functioning as a natural refugium from potential problems caused by zebra mussels.

  13. Biogeochemical alteration of the benthic environment by the zebra mussel Dreissena polymorpha (Pallas

    Directory of Open Access Journals (Sweden)

    Alina Krevš

    2010-12-01

    Full Text Available The aim of this study was to verify whether the biogeochemicalfeatures (e.g. concentration of nutrients, oxygen consumption,mineralization rate, Eh of sediments changed by the zebra musselor its shell deposits differ from those in the ambient soft bottom,and how these differences are related to the structure of benthicmacroinvertebrates. In 2006 three sampling sessions were carriedout in the Curonian Lagoon, SE Baltic Sea, at three pre-definedsites, corresponding to different bottom types: zebra musselbed, zebra mussel shell deposits and bare soft sediments. Similarityanalysis of biogeochemical parameters indicated that bottom sedimentscovered with zebra mussel shell deposits were rather distinctfrom the other bottom types because of the lowest total organicmatter mineralization rate and highest organic carbon, totalphosphorus and total nitrogen content. The parameters measuredin the zebra mussel bed did not deviate conspicuously from thevalues observed in bare bottoms, except for the higher rate ofoxygen consumption in the upper sediment layer. Unsuitable anoxicconditions on the one hand and the "attractive" shelters providedby zebra mussels on the other hand may promote the epifaunallife style in the habitats formed by dense zebra mussel clumps.

  14. Occurrence of zebra mussels in near-shore areas of western Lake Erie

    Science.gov (United States)

    Custer, Christine M.; Custer, T.W.

    1997-01-01

    Zebra mussels (Dreissena polymorpha) invaded the Great Lakes in the mid-1980s and quickly reached high densities. The objective of this study was to determine current consumption of zebra mussels by waterfowl in the Great Lakes region. Feeding Lesser Scaups (Aythya affinis), Greater Scaups (A. marila), Canvasbacks (A. valisineria), Redheads (A. americana), Buffleheads (Bucephala albeola) and Common Goldeneyes (B. clangula) were collected in western Lake Erie and in Lake St. Clair between fall and spring, 1992-1993 to determine food habits. All 10 Redheads, 97% of Lesser Scaups, 83% of Goldeneyes, 60% of Buffleheads and 9% of Canvasbacks contained one or more zebra mussels in their upper gastrointestinal tracts. The aggregate percent of zebra mussels in the diet of Lesser Scaups was higher in Lake Erie (98.6%) than in Lake St. Clair (54.4%). Zebra mussels, (aggregate percent) dominated the diet of Common Goldeneyes (79.2%) but not in Buffleheads (23.5%), Redheads (21%) or Canvasbacks (9%). Lesser Scaups from Lake Erie fed on larger zebra mussels ( = 10.7 i?? 0.66 mm SE) than did Lesser Scaups from Lake St. Clair ( = 4.4 i?? 0.22 mm). Lesser Scaups, Buffleheads and Common Goldeneyes from Lake Erie consumed zebra mussels of similar size.

  15. The Effect of Zebra Mussels on Algal Community Structure in an Impounded River System

    Science.gov (United States)

    Trumble, A. F.; Luttenton, M.

    2005-05-01

    The zebra mussel, Dreissena polymorpha, invaded the Great Lakes Region in the mid 1980's, and subsequently colonized inland lakes and coastal river systems through secondary invasions. The Muskegon River below Croton Dam was colonized by zebra mussels in 2000 following their introduction into Croton impoundment in the late 1990's. No zebra mussels were found below Croton Dam in 1999 but had increased to 25,000 m-2 by 2001. We examined the affect of zebra mussels on epilithic periphyton communities by comparing plots that were and were not colonized by zebra mussels. Chlorophyll a increased in both treatments over time but was significantly higher in control plots than in zebra mussel plots. The concentration of chlorophyll a in the control plots increased from 14 µgcm-2 to 26 µgcm-2 and the concentration in the zebra mussel plots started at 12 µgcm-2, peaked at 19 µgcm-2, and then decreased to 15 µgcm-2 over a 6 week period. In a related experiment using artificial streams, chlorophyll a increased with increasing zebra mussel density, but differences were not significant. The different trends observed between the two experiments may be explained in part by arthropod invertebrates associated with zebra mussel populations.

  16. Preference of redear sunfish on zebra mussels and rams-horn snails

    Science.gov (United States)

    French, John R. P.; Morgan, Michael N.

    1995-01-01

    We tested prey preferences of adult (200- to 222-mm long) redear sunfish (Lepomis microlophus) on two size classes of zebra mussels (Dreissena polymorpha) and two-ridge rams-horns (Helisoma anceps) in experimental aquaria. We also tested physical limitations on consuming these mollusks and determined prey bioenergetic profitability. Redear sunfish strongly preferred rams-horns over zebra mussels, but they displayed no size preference for either prey. Ingestion was not physically limited since both prey species up to 15-mm long fit within the pharyngeal gapes of redear sunfish. Rams-horns were more bioenergetically profitable than zebra mussels and ingestion of rams-horn shell fragments was about three times less than zebra mussels. Rams-horns were somewhat more resistant to shell-crushing, but all size ranges of both prey species tested were crushable by redear sunfish. These studies suggested that the redear sunfish should not be considered a panacea for biological control of zebra mussels.

  17. The use of positive reinforcement in training zebra sharks (Stegostoma fasciatum).

    Science.gov (United States)

    Marranzino, Ashley

    2013-01-01

    Positive reinforcement training (PRT) was used on 4 adult zebra sharks, Stegostoma fasciatum, housed at the Downtown Aquarium, Denver, to determine the ability of zebra sharks to become desensitized to various stimuli associated with veterinary procedures. One male and 3 female sharks were trained for 12 weeks. As a result of PRT, all 4 zebra sharks were desensitized to staying within a closed holding tank off of the main exhibit, the presence of multiple trainers in the closed holding tank, and tactile stimulation. One of the 4 zebra sharks was also successfully desensitized to the presence of a stretcher being brought into the holding tank. All of these procedures are common in veterinary examinations, and it is hoped that desensitization to these stimuli will reduce the stress associated with examinations. The training accomplished has allowed for easier maintenance of the zebra sharks by the aquarium staff and an improvement in the care of the sharks.

  18. Molecular phylogenetics of finches and sparrows: consequences of character state removal in cytochrome b sequences.

    Science.gov (United States)

    Groth, J G

    1998-12-01

    The complete mitochondrial cytochrome b genes of 53 genera of oscine passerine birds representing the major groups of finches and some allies were compared. Phylogenetic trees resulting from three levels of character partition removal (no data removed, transitions at third positions of codons removed, and all transitions removed [transversion parsimony]) were generally concordant, and all supported several basic statements regarding relationships of finches and finch-like birds, including: (1) larks (Alaudidae) show no close relationship to any finch group; (2) Peucedramus (olive warbler) is phylogenetically far removed from true wood warblers; (3) a clade consisting of fringillids, passerids, motacillids, and emberizids is supported, and this clade is characterized by evolution of a vestigial 10th wing primary; and (4) Hawaiian honeycreepers are derived from within the cardueline finches. Excluding transition substitutions at third positions of codons resulted in phylogenetic trees similar to, but with greater bootstrap nodal support than, trees derived using either all data (equally weighted) or transversion parsimony. Relative to the shortest trees obtained using all data, the topologies obtained after elimination of third-position transitions showed only slight increases in realized treelength and homoplasy. These increases were negligable compared to increases in overall nodal support; therefore, this partition removal scheme may enhance recovery of deep phylogenetic signal in protein-coding DNA datasets. Copyright 1998 Academic Press.

  19. Interpretation of experiments made in ZEBRA CADENZA assemblies with CEA formulary

    International Nuclear Information System (INIS)

    D'Angelo, A.; Rimpault, G.

    1983-06-01

    A benchmark exercise on fast critical heterogeneity method assessment has been proposed in the framework of NEACRP. It is based on the analysis of two integral experiments performed by UKAEA on the ZEBRA facility (the CADENZA assemblies): - a plate fuelled core (ZEBRA 22); - a 75% pin fuelled core (ZEBRA 23). The interpretation of these experiments has been done using the current standard CEA methods. We find a relevant (650 pcm) discrepancy between the ''k'' values of ZEBRA 22 and ZEBRA 23 pin assemblies. We try in this report to find out the origin of this discrepancy. The spatial k-value calculation results and corrections are affected by nomore than 150 pcm and are partially correlated. Moreover, this discrepancy does not seem to be explained in terms of homogenous infinite dilute cross section effects. It has been found that most of the discrepancy can be traced back to heterogeneity effects, and mainly to the heterogeneity effects of the metallic fuel plate in the metallic fuel plate in the ZEBRA 22 cell. Finally, the pin core gives, in the CEA analysis, a Keff E-C value well inside the known performance of the adjusted CARNAVAL IV formulaire (i.e. E-C =+ 300 + +500+-200 pcm) for plutonium fuelled cores

  20. Zebra mussels anchor byssal threads faster and tighter than quagga mussels in flow.

    Science.gov (United States)

    Peyer, Suzanne M; McCarthy, Alice J; Lee, Carol Eunmi

    2009-07-01

    While the invasive zebra mussel Dreissena polymorpha has rapidly spread throughout the Great Lakes and inland waterways, it is being displaced by the quagga mussel Dreissena bugensis in shallow water habitats. However, zebra mussels remain dominant in areas with higher water velocity. We hypothesized that the persistence of zebra over quagga mussels in habitats with higher water velocity might result from greater rate and strength of byssal thread attachment. We examined whether zebra mussels relative to quagga mussels have: (1) higher byssal thread synthesis rate, (2) lower dislodgment in flow and (3) greater mechanical force required for detachment from substrate. Specifically, we examined byssal thread synthesis rate and dislodgment of both species in response to water velocities of 0, 50, 100 and 180 cm s(-1). Byssal thread synthesis rate was significantly higher for zebra than for quagga mussels at all velocities. Dislodgment from the substrate increased for both species with increasing velocity but was significantly lower for zebra than for quagga mussels. We also tested the mechanical force to detach mussels after short (32 h) and long (two and three months) periods of attachment on hard substrate. Detachment force was significantly higher for zebra than for quagga mussels only after short-term attachment. Higher byssal thread synthesis rate in zebra mussels was a likely factor that minimized their dislodgment in flow and increased short-term attachment strength. Differences in byssal thread synthesis rate between the two species might partly account for the ability of zebra mussels to maintain dominance over quagga mussels in habitats with high velocities.

  1. Learning to breathe and sing: development of respiratory-vocal coordination in young songbirds.

    Science.gov (United States)

    Veit, Lena; Aronov, Dmitriy; Fee, Michale S

    2011-10-01

    How do animals with learned vocalizations coordinate vocal production with respiration? Songbirds such as the zebra finch learn their songs, beginning with highly variable babbling vocalizations known as subsong. After several weeks of practice, zebra finches are able to produce a precisely timed pattern of syllables and silences, precisely coordinated with expiratory and inspiratory pulses (Franz M, Goller F. J Neurobiol 51: 129-141, 2002). While respiration in adult song is well described, relatively little is known about respiratory patterns in subsong or about the processes by which respiratory and vocal patterns become coordinated. To address these questions, we recorded thoracic air sac pressure in juvenile zebra finches prior to the appearance of any consistent temporal or acoustic structure in their songs. We found that subsong contains brief inspiratory pulses (50 ms) alternating with longer pulses of sustained expiratory pressure (50-500 ms). In striking contrast to adult song, expiratory pulses often contained multiple (0-8) variably timed syllables separated by expiratory gaps and were only partially vocalized. During development, expiratory pulses became shorter and more stereotyped in duration with shorter and fewer nonvocalized parts. These developmental changes eventually resulted in the production of a single syllable per expiratory pulse and a single inspiratory pulse filling each gap, forming a coordinated sequence similar to that of adult song. To examine the role of forebrain song-control nuclei in the development of respiratory patterns, we performed pressure recordings before and after lesions of nucleus HVC (proper name) and found that this manipulation reverses the developmental trends in measures of the respiratory pattern.

  2. Invasion of the Zebra Mussels: A Mock Trial Activity

    Science.gov (United States)

    Beck, Judy A.; Czerniak, Charlene M.

    2005-01-01

    In this activity, students learn about the important topic of invasive species, specifically Zebra Mussels. Students role-play different characters in a real-life situation: the trial of the Zebra Mussel for unlawful disruption of the Great Lakes ecosystem. Students will also learn about jurisprudential inquiry by examining the trial process. This…

  3. Large diurnal temperature range increases bird sensitivity to climate change

    NARCIS (Netherlands)

    Briga, Michael; Verhulst, Simon

    2015-01-01

    Climate variability is changing on multiple temporal scales, and little is known of the consequences of increases in short-term variability, particularly in endotherms. Using mortality data with high temporal resolution of zebra finches living in large outdoor aviaries (5 years, 359.220 bird-days),

  4. One-Stage Correction Surgery of Scoliosis Associated With Syringomyelia: Is it Safe to Leave Untreated a Syrinx Without Neurological Symptom?

    Science.gov (United States)

    Wang, Guodong; Sun, Jianmin; Jiang, Zhensong; Cui, Xingang; Cui, Jiangchao

    2015-06-01

    Retrospective study. To investigate the safety to leave a syrinx untreated in 1-stage correction surgery of scoliosis associated with syringomyelia without progressive neurological symptom. The present protocol for patients with scoliosis secondary to syringomyelia advocated to treat the syrinx first because of the increased risk in correction surgery. However, in daily life, these patients could still do lateral bending, in which spinal cord distracted albeit without any neurological symptom occurred. Twenty-one consecutive patients with scoliosis associated with syringomyelia with or without Chiari malformation underwent surgery in our department from 2003 to 2010 were included in this study. Patients with progressive neural deficits were excluded. Every patient received detailed neurological and radiologic examination before the surgery, including whole spine films, lateral-bending and fulcrum-bending films, 3-dimensional computed tomography scan, and magnetic resonance imaging. All the patients underwent 1-stage correction surgery without treatment of syrinx. During the surgery, Spinal Cord Monitor (SCM) and wake-up test were used to prevent serious neurological complications. At follow-up, patients received neurological examination and whole spine x-ray films. There were 13 male and 8 female patients. Before the surgery, 3 patients complained wasting of the intrinsic muscles of hand, 1 complained numbness of left upper extremity, and 4 complained back pain. Negative abdomen reflex occurred on 12 of 21 patients. All the patients were single major curve, including 14 thoracic curves and 7 thoracolumbar curves. The mean preoperative Cobb angle of scoliosis was 68.05±20.1 degrees, on bending films was 39.48±21.56 degrees, postoperative was 23.19±14.14 degrees, at final follow-up was 25.76±14.46 degrees. The mean flexibility was 0.452±0.158, correction ratio was 0.685±0.140. During the operation, SCM showed motor evoked potential (MEP) loss transiently in 2

  5. Evaluation of zebra mussels (Dreissena polymorpha) as biomonitors of mercury contamination in aquatic ecosystems.

    Science.gov (United States)

    Blackwell, Bradley D; Driscoll, Charles T; Spada, Michael E; Todorova, Svetoslava G; Montesdeoca, Mario R

    2013-03-01

    Zebra mussels have invaded many lakes in the United States and could be a useful tool for monitoring responses of aquatic biota to changes in mercury loading. The goal of the present study was to evaluate zebra mussels for use as a biomonitor of mercury contamination by comparing zebra mussel mercury concentrations between a lake with only indirect atmospheric mercury contamination (Otisco Lake, NY, USA) and a lake that was directly contaminated by mercury discharges (Onondaga Lake, NY, USA). Zebra mussels were sampled in both the spring and fall of 2004 and 2005. Total mercury (THg) concentrations in zebra mussels were approximately seven times greater in Onondaga Lake than in Otisco Lake, and water column mercury concentrations differed by an order of magnitude between the two lakes. Seasonal differences resulted in significantly higher zebra mussel THg concentrations during the fall for both lakes. There was also significant variation among different sampling sites in Onondaga Lake. Mussel methylmercury concentrations averaged 53% of THg concentrations but were highly variable. Strong relationships between water column THg and zebra mussel THg suggest that zebra mussels are a good indicator of aquatic mercury concentrations and could be used as an effective biomonitor of mercury contamination in aquatic ecosystems. Copyright © 2013 SETAC.

  6. Predation of the zebra mussel (Dreissena polymorpha) by freshwater drum in western Lake Erie

    Science.gov (United States)

    French, John R. P.; Bur, Michael T.; Nalepa, Thomas F.; Schloesser, Donald W.

    1992-01-01

    Environmental and economic problems associated with the colonization of zebra mussels (Dreissena polymorpha) in western Lake Erie created a need to investigate control mechanisms. Predation by fishes is one potential means of control, but predation on zebra mussels by native fishes in Lake Erie is unknown. The freshwater drum (Aplodinotus grunniens) is the most likely fish predator since it is the only fish with pharyngeal teeth capable of crushing mollusk shells. In 1990, freshwater drum were collected in western Lake Erie from 9 sites near rocky reefs and 13 sites with silt or sand bottoms, and gut contents were examined. Predation on zebra mussels increased as drum size increased. Small drum (200-249 mm in length) fed mainly on dipterans, amphipods, and small fish; small zebra mussels (375 mm in length) fed almost exclusively on zebra mussels (seasons and locations combined). The smallest drum capable of crushing zebra mussel shells was 265 mm. Since freshwater drum over 375 mm feed heavily on zebra mussels, they may become a possible biological control mechanism for mussels in portions of North America.

  7. Sexual dimorphism in striatal dopaminergic responses promotes monogamy in social songbirds.

    Science.gov (United States)

    Tokarev, Kirill; Hyland Bruno, Julia; Ljubičić, Iva; Kothari, Paresh J; Helekar, Santosh A; Tchernichovski, Ofer; Voss, Henning U

    2017-08-11

    In many songbird species, males sing to attract females and repel rivals. How can gregarious, non-territorial songbirds such as zebra finches, where females have access to numerous males, sustain monogamy? We found that the dopaminergic reward circuitry of zebra finches can simultaneously promote social cohesion and breeding boundaries. Surprisingly, in unmated males but not in females, striatal dopamine neurotransmission was elevated after hearing songs. Behaviorally too, unmated males but not females persistently exchanged mild punishments in return for songs. Song reinforcement diminished when dopamine receptors were blocked. In females, we observed song reinforcement exclusively to the mate's song, although their striatal dopamine neurotransmission was only slightly elevated. These findings suggest that song-triggered dopaminergic activation serves a dual function in social songbirds: as low-threshold social reinforcement in males and as ultra-selective sexual reinforcement in females. Co-evolution of sexually dimorphic reinforcement systems can explain the coexistence of gregariousness and monogamy.

  8. Social learning in nest-building birds: a role for familiarity.

    Science.gov (United States)

    Guillette, Lauren M; Scott, Alice C Y; Healy, Susan D

    2016-03-30

    It is becoming apparent that birds learn from their own experiences of nest building. What is not clear is whether birds can learn from watching conspecifics build. As social learning allows an animal to gain information without engaging in costly trial-and-error learning, first-time builders should exploit the successful habits of experienced builders. We presented first-time nest-building male zebra finches with either a familiar or an unfamiliar conspecific male building with material of a colour the observer did not like. When given the opportunity to build, males that had watched a familiar male build switched their material preference to that used by the familiar male. Males that observed unfamiliar birds did not. Thus, first-time nest builders use social information and copy the nest material choices when demonstrators are familiar but not when they are strangers. The relationships between individuals therefore influence how nest-building expertise is socially transmitted in zebra finches. © 2016 The Author(s).

  9. Interactions among zebra mussel shells, invertebrate prey, and Eurasian ruffe or yellow perch

    Science.gov (United States)

    Kolar, C.S.; Fullerton, A.H.; Martin, K.M.; Lamberti, G.A.

    2002-01-01

    The exotic zebra mussel, Dreissena polymorpha, is established in all of the Laurentian Great Lakes and may affect benthivorous fishes by increasing the complexity of benthic substrates and changing energy flow patterns within the food web. Native yellow perch, Perca flavescens, and the nonindigenous Eurasian ruffe, Gymnocephalus cernuus, are benthivores that may compete for limited food resources. As ruffe spread to areas with more dense zebra mussel populations, the zone of interaction among zebra mussels, yellow perch, and ruffe will increase and intensify. In the laboratory, the effect of zebra mussel shells on the ability of these fishes to forage on amphipods (Gammarus pseudolimnaeus) and chironomids (Chironomus plumosus) was examined in light and darkness. In 12 h, ruffe consumed more amphipods than did similar-sized yellow perch, particularly in darkness on bare cobble, and in light within zebra mussels. Amphipods decreased activity more in the presence of ruffe than yellow perch. More amphipods were found in zebra mussel shells than in bare cobble, whether or not fish were present. In darkness, when ruffe consumed more amphipods on bare cobble, amphipods became more associated with zebra mussel shells. Although ruffe consumed more amphipods than yellow perch, perch consumed more chironomids than ruffe on bare cobble. The presence of zebra mussel shells altered the relative consumption of invertebrates in some substrate-light combinations. Experiments such as these help to improve understanding of the direct and indirect effects of predation between and among native and nonindigenous species that may exert structuring forces on the nearshore communities of the Great Lakes currently or in the future.

  10. IMPACT OF WATER PH ON ZEBRA MUSSEL MORTALITY

    International Nuclear Information System (INIS)

    Molloy, Daniel P.

    2002-01-01

    The experiments conducted this past quarter have suggested that the bacterium Pseudomonas fluorescens strain CL0145A is effective at killing zebra mussels throughout the entire range of pH values tested (7.2 to 8.6). Highest mortality was achieved at pH values characteristic of preferred zebra mussel waterbodies, i.e., hard waters with a range of 7.8 to 8.6. In all water types tested, however, ranging from very soft to very hard, considerable mussel kill was achieved (83 to 99% mean mortality), suggesting that regardless of the pH or hardness of the treated water, significant mussel kill can be achieved upon treatment with P. fluorescens strain CL0145A. These results further support the concept that this bacterium has significant potential for use as a zebra mussel control agent in power plant pipes receiving waters with a wide range of physical and chemical characteristics

  11. IMPACT OF WATER PH ON ZEBRA MUSSEL MORTALITY

    Energy Technology Data Exchange (ETDEWEB)

    Daniel P. Molloy

    2002-10-15

    The experiments conducted this past quarter have suggested that the bacterium Pseudomonas fluorescens strain CL0145A is effective at killing zebra mussels throughout the entire range of pH values tested (7.2 to 8.6). Highest mortality was achieved at pH values characteristic of preferred zebra mussel waterbodies, i.e., hard waters with a range of 7.8 to 8.6. In all water types tested, however, ranging from very soft to very hard, considerable mussel kill was achieved (83 to 99% mean mortality), suggesting that regardless of the pH or hardness of the treated water, significant mussel kill can be achieved upon treatment with P. fluorescens strain CL0145A. These results further support the concept that this bacterium has significant potential for use as a zebra mussel control agent in power plant pipes receiving waters with a wide range of physical and chemical characteristics.

  12. Quagga and zebra mussels: biology, impacts, and control

    Science.gov (United States)

    Nalepa, Thomas F.; Schloesser, Don W.; Nalepa, Thomas F.; Schloesser, Don W.

    2013-01-01

    Quagga and Zebra Mussels: Biology, Impacts, and Control, Second Edition provides a broad view of the zebra/quagga mussel issue, offering a historic perspective and up-to-date information on mussel research. Comprising 48 chapters, this second edition includes reviews of mussel morphology, physiology, and behavior. It details mussel distribution and spread in Europe and across North America, and examines policy and regulatory responses, management strategies, and mitigation efforts. In addition, this book provides extensive coverage of the impact of invasive mussel species on freshwater ecosystems, including effects on water clarity, phytoplankton, water quality, food web changes, and consequences to other aquatic fauna. It also reviews and offers new insights on how zebra and quagga mussels respond and adapt to varying environmental conditions. This new edition includes seven video clips that complement chapter text and, through visual documentation, provide a greater understanding of mussel behavior and distribution.

  13. How well can fishes prey on zebra mussels in eastern North America?

    Science.gov (United States)

    French, John R. P.

    1993-01-01

    Literature on mollusk-eating fishes was reviewed to determine the potential for different species of fish to control zebra mussels in eastern North America. At least six species are potential predators of zebra mussels because they possess (1) both upper and lower pharyngeal teeth or (2) lower pharyngeal teeth and chewing pads located on the dorsal roof for crushing mollusk shells. Freshwater drum (Aplodinotus grunniens) and two centrarchids, redear sunfish (Lepomis microlophus) and pumpkinseed (L. gibbosus), possess both upper and lower pharyngeal teeth and are likely to consume more zebra mussels than fishes with only lower pharyngeal teeth. Only two catostomid species, copper and river redhorses (Moxostoma hubbsi and M. carinatum), have chewing pads that enable them to crush mollusks. The exotic omnivorous common carp (Cyprinus carpio), possessing lower teeth and a chewing pad, may prey on zebra mussels when aquatic insect larvae, its preferred food, become rare. Managing populations of drum, sunfishes and redhorses to reduce exploitation of large individuals and improve their habitats are suggested as means to intensify biological control of zebra mussels in eastern North America. Other Eurasian molluscivores, the roach (Rutilus rutilus) and the black carp (Mylopharyngodon piceus) should not be introduced into North America because research has shown repeatedly that an introduced biological controller usually does not forage for unwanted pests or reside only in preferred habitats of pests. Drum, sunfishes and redhorses should be preferred over these exotics as biological controllers of zebra mussels in North America because these native fishes will likely occupy newly established habitats of zebra mussels.

  14. Three Molecular Markers Show No Evidence of Population Genetic Structure in the Gouldian Finch (Erythrura gouldiae.

    Directory of Open Access Journals (Sweden)

    Peri E Bolton

    Full Text Available Assessment of genetic diversity and connectivity between regions can inform conservation managers about risk of inbreeding, potential for adaptation and where population boundaries lie. The Gouldian finch (Erythrura gouldiae is a threatened species in northern Australia, occupying the savannah woodlands of the biogeographically complex monsoon tropics. We present the most comprehensive population genetic analysis of diversity and structure the Gouldian finch using 16 microsatellite markers, mitochondrial control region and 3,389 SNPs from genotyping-by-sequencing. Mitochondrial diversity is compared across three related, co-distributed finches with different conservation threat-statuses. There was no evidence of genetic differentiation across the western part of the range in any of the molecular markers, and haplotype diversity but not richness was lower than a common co-distributed species. Individuals within the panmictic population in the west may be highly dispersive within this wide area, and we urge caution when interpreting anecdotal observations of changes to the distribution and/or flock sizes of Gouldian finch populations as evidence of overall changes to the population size of this species.

  15. Systemic equid alphaherpesvirus 9 in a Grant's zebra.

    Science.gov (United States)

    Moeller, Robert B; Crossley, Beate; Pipkin, Arlena; Li, Yanqiu; Balasuriya, Udeni B R

    2018-04-01

    A 2-y-old female Grant's zebra ( Equus quagga [ burchellii] boehmi) was presented with a clinical history of depression, anorexia, and weakness of 1-wk duration. Postmortem examination identified ulcers on the tongue and palate; a large abscess adjacent to the larynx; left lung consolidation; mild swelling, darkening, and congestion of the liver with accentuation of the lobular pattern; and edema and congestion of the distal small and large intestines. Histologic examination identified necrotizing bronchopneumonia, necrotizing hepatitis, nephritis, and enterocolitis. Eosinophilic intranuclear inclusions were detected in syncytial cells and degenerate bronchial epithelium in the lungs and in some hepatocytes associated with necrotic foci. Bacterial cultures of the lung, liver, and laryngeal abscess failed to detect any significant pathogen. Lung and liver tested positive for equine herpesvirus with neuropathogenic marker by real-time PCR. Subsequently, equine herpesvirus was isolated in tissue culture, and the entire viral DNA polymerase gene (ORF30) was sequenced. The zebra lung isolate had a very close nucleotide and amino acid sequence identity to equid alphaherpesvirus 9 (EHV-9; 99.6% and 99.8%, respectively) in contrast to the neuropathogenic T953 strain of EHV-1 (94.7% and 96.6%, respectively). Although zebras are considered the natural host for EHV-9, we document an unusual acute systemic, fatal EHV-9 infection in a 2-y-old Grant's zebra.

  16. In situ vocal fold properties and pitch prediction by dynamic actuation of the songbird syrinx

    DEFF Research Database (Denmark)

    Düring, Daniel N; Knörlein, Benjamin J; Elemans, Coen P H

    2017-01-01

    , forces and torques exerted on, and motion of the syringeal skeleton during song. Here, we present a novel marker-based 3D stereoscopic imaging technique to reconstruct 3D motion of servo-controlled actuation of syringeal muscle insertions sites in vitro and focus on two muscles controlling sound pitch......The biomechanics of sound production forms an integral part of the neuromechanical control loop of avian vocal motor control. However, we critically lack quantification of basic biomechanical parameters describing the vocal organ, the syrinx, such as material properties of syringeal elements...... motion and forces, acoustic effects of muscle recruitment, and calibration of computational birdsong models, enabling experimental access to the entire neuromechanical control loop of vocal motor control....

  17. The zebra mussel

    International Nuclear Information System (INIS)

    Bertran, A.; Esparza, J.L.; Munte, L.

    2010-01-01

    The aim of this article is, on the one hand, to provide information about the zebra mussel, its behavior, its effect on the ecosystem and the problems it poses for industry (especially in the CNA cooling systems) and, on the other hand, to review the strategies and technologies needed to control de mussel and to present the solution adopted by the power plant to combat the plague. (Author).

  18. Distribution of language-related Cntnap2 protein in neural circuits critical for vocal learning.

    Science.gov (United States)

    Condro, Michael C; White, Stephanie A

    2014-01-01

    Variants of the contactin associated protein-like 2 (Cntnap2) gene are risk factors for language-related disorders including autism spectrum disorder, specific language impairment, and stuttering. Songbirds are useful models for study of human speech disorders due to their shared capacity for vocal learning, which relies on similar cortico-basal ganglia circuitry and genetic factors. Here we investigate Cntnap2 protein expression in the brain of the zebra finch, a songbird species in which males, but not females, learn their courtship songs. We hypothesize that Cntnap2 has overlapping functions in vocal learning species, and expect to find protein expression in song-related areas of the zebra finch brain. We further expect that the distribution of this membrane-bound protein may not completely mirror its mRNA distribution due to the distinct subcellular localization of the two molecular species. We find that Cntnap2 protein is enriched in several song control regions relative to surrounding tissues, particularly within the adult male, but not female, robust nucleus of the arcopallium (RA), a cortical song control region analogous to human layer 5 primary motor cortex. The onset of this sexually dimorphic expression coincides with the onset of sensorimotor learning in developing males. Enrichment in male RA appears due to expression in projection neurons within the nucleus, as well as to additional expression in nerve terminals of cortical projections to RA from the lateral magnocellular nucleus of the nidopallium. Cntnap2 protein expression in zebra finch brain supports the hypothesis that this molecule affects neural connectivity critical for vocal learning across taxonomic classes. Copyright © 2013 Wiley Periodicals, Inc.

  19. Efficacy of candidate chemicals for preventing attachment of zebra mussels (Dreissena polymorpha)

    Science.gov (United States)

    Cope, W.G.; Bartsch, M.R.; Marking, L.L.

    1997-01-01

    Forty-seven chemicals having potential for preventing the attachment of zebra mussels Dreissena polymorpha were identified and tested. For each chemical, 15 zebra mussels (5-8-mm shell length) in each of two replicates and six treatments were exposed for 48 h followed by a 48-h postexposure period in untreated water. Eleven of the chemicals inhibited the reattachment of zebra mussels after the 48-h exposure; eight had EC50 values ranging from 0.4 to 5.4 mg /L, and three had EC50 values ranging from 19.4 to 29.0 mg/L. Based on an analysis of chemical cost, solubility in water, anticipated treatment concentrations, and potential hazards to humans or the environment, three of the most promising chemicals, all antioxidants (butylated hydroxyanisole [BHA], tert-butylhydroquinone, and tannic acid) were tested on nontarget fish (bluegill, Lepomis macrochirus; channel catfish, Ictalurus punctatus; and rainbow trout, Oncorhynchus mykiss). These chemicals were not selectively toxic to zebra mussels; only the tests with bluegill and BHA and with channel catfish and tannic acid had 48-h LC50 values greater than the concentrations effective for preventing the reattachment of zebra mussels. Although the attachment of zebra mussels can be prevented with selected antioxidants, an alternative formulation should be investigated to minimize effects on nontarget organisms, such as fish.

  20. Food habits of diving ducks in the Great Lakes after the zebra mussel invasion

    Science.gov (United States)

    Custer, Christine M.; Custer, T.W.

    1996-01-01

    Zebra mussels (Dreissena polymorpha) invaded the Great Lakes in the mid-1980s and quickly reached high densities. The objective of this study was to determine current consumption of zebra mussels by waterfowl in the Great Lakes region. Feeding Lesser Scaups (Aythya affinis), Greater Scaups (A. marila), Canvasbacks (A. valisineria), Redheads (A. americana), Buffleheads (Bucephala albeola) and Common Goldeneyes (B. clangula) were collected in western Lake Erie and in Lake St. Clair between fall and spring, 1992-1993 to determine food habits. All 10 Redheads, 97% of Lesser Scaups, 83% of Goldeneyes, 60% of Buffleheads and 9% of Canvasbacks contained one or more zebra mussels in their upper gastrointestinal tracts. The aggregate percent of zebra mussels in the diet of Lesser Scaups was higher in Lake Erie (98.6%) than in Lake St. Clair (54.4%). Zebra mussels (aggregate percent) dominated the diet of Common Goldeneyes (79.2%) but not in Buffleheads (23.5%), Redheads (21%) or Canvasbacks (9%). Lesser Scaups from Lake Erie fed on larger zebra mussels ( = 10.7 i?? 0.66 mm SE) than did Lesser Scaups from Lake St. Clair ( = 4.4 i?? 0.22 mm). Lesser Scaups, Buffleheads and Common Goldeneyes from Lake Erie consumed zebra mussels of similar size.

  1. Exploratory behavior is linked to stress physiology and social network centrality in free-living house finches (Haemorhous mexicanus).

    Science.gov (United States)

    Moyers, Sahnzi C; Adelman, James S; Farine, Damien R; Moore, Ignacio T; Hawley, Dana M

    2018-05-21

    Animal personality has been linked to individual variation in both stress physiology and social behaviors, but few studies have simultaneously examined covariation between personality traits, stress hormone levels, and behaviors in free-living animals. We investigated relationships between exploratory behavior (one aspect of animal personality), stress physiology, and social and foraging behaviors in wild house finches (Haemorhous mexicanus). We conducted novel environment assays after collecting samples of baseline and stress-induced plasma corticosterone concentrations from a subset of house finches. We then fitted individuals with Passive Integrated Transponder tags and monitored feeder use and social interactions at radio-frequency identification equipped bird feeders. First, we found that individuals with higher baseline corticosterone concentrations exhibit more exploratory behaviors in a novel environment. Second, more exploratory individuals interacted with more unique conspecifics in the wild, though this result was stronger for female than for male house finches. Third, individuals that were quick to begin exploring interacted more frequently with conspecifics than slow-exploring individuals. Finally, exploratory behaviors were unrelated to foraging behaviors, including the amount of time spent on bird feeders, a behavior previously shown to be predictive of acquiring a bacterial disease that causes annual epidemics in house finches. Overall, our results indicate that individual differences in exploratory behavior are linked to variation in both stress physiology and social network traits in free-living house finches. Such covariation has important implications for house finch ecology, as both traits can contribute to fitness in the wild. Copyright © 2018 Elsevier Inc. All rights reserved.

  2. Model calculations for the airborne Fast Ice Nuclei CHamber FINCH-HALO

    Science.gov (United States)

    Nillius, B.; Bingemer, H.; Bundke, U.; Jaenicke, R.; Reimann, B.; Wetter, T.

    2009-04-01

    Ice nuclei (IN) initiate the formation of primary ice in tropospheric clouds. In mixed phase clouds the primary ice crystals can grow very fast by the Bergeron-Findeisen process (Findeisen, 1938) at the expense of evaporating water droplets, and form precipitation. Thus, IN are essential for the development of precipitation in mixed phase clouds in the middle latitude. However, the role of IN in the development of clouds is still poorly understood and needs to be studied (Levin and Cotton, 2007). A Fast Ice Nuclei CHamber (FINCH-HALO) for airborne operation on the High And LOng Range research aircraft (HALO) is under development at the Institute for Atmosphere and Environment University Frankfurt. IN particles are activated within the chamber at certain ice super-saturation and temperature by mixing three gas flows, a warm moist, a cold dry, and an aerosol flow. After activation the particles will grow within a processing chamber. In an optical depolarisation detector droplets and ice crystals are detected separately. The setup of the new FINCH-HALO instrument is based on the ground based IN counter FINCH (Bundke, 2008). In FINCH-HALO a new cooling unit is used. Thus, measurements down to -40°C are possible. Furthermore minor changes of the inlet section where the mixing occurs were done. The contribution will present 3D model calculations with FLUENT of the flow conditions in the new inlet section for different pressure levels during a flight typical for HALO. Growth rates of ice crystals in the chamber at different temperature and super-saturation will be shown. References: Bundke U., B. Nillius, R. Jaenicke, T. Wetter, H. Klein, H. Bingemer, (2008). The Fast Ice Nucleus Chamber FINCH, Atmospheric Research, doi:10.1016/j.atmosres.2008.02.008 Findeisen, R., (1938). Meteorologisch-physikalische Begebenheiten der Vereisung in der Atmosphäre. Hauptversammlung 1938 der Lilienthal-Gesellschaft. Levin, Z., W. Cotton, (2007). Aerosol pollution impact on precipitation

  3. Economic impacts of zebra mussels on drinking water treatment and electric power generation facilities.

    Science.gov (United States)

    Connelly, Nancy A; O'Neill, Charles R; Knuth, Barbara A; Brown, Tommy L

    2007-07-01

    Invasions of nonnative species such as zebra mussels can have both ecological and economic consequences. The economic impacts of zebra mussels have not been examined in detail since the mid-1990s. The purpose of this study was to quantify the annual and cumulative economic impact of zebra mussels on surface water-dependent drinking water treatment and electric power generation facilities (where previous research indicated the greatest impacts). The study time frame was from the first full year after discovery in North America (Lake St. Clair, 1989) to the present (2004); the study area was throughout the mussels' North American range. A mail survey resulted in a response rate of 31% for electric power companies and 41% for drinking water treatment plants. Telephone interviews with a sample of nonrespondents assessed nonresponse bias; only one difference was found and adjusted for. Over one-third (37%) of surveyed facilities reported finding zebra mussels in the facility and almost half (45%) have initiated preventive measures to prevent zebra mussels from entering the facility operations. Almost all surveyed facilities (91%) with zebra mussels have used control or mitigation alternatives to remove or control zebra mussels. We estimated that 36% of surveyed facilities experienced an economic impact. Expanding the sample to the population of the study area, we estimated 267 million dollars (BCa 95% CI = 161 million dollars - 467 million dollars) in total economic costs for electric generation and water treatment facilities through late 2004, since 1989. Annual costs were greater (44,000 dollars/facility) during the early years of zebra mussel infestation than in recent years (30,000 dollars). As a result of this and other factors, early predictions of the ultimate costs of the zebra mussel invasion may have been excessive.

  4. Optimal Management of a Potential Invader: The Case of Zebra Mussels in Florida

    OpenAIRE

    Lee, Donna J.; Adams, Damian C.; Rossi, Frederick J.

    2007-01-01

    Dominant users of Lake Okeechobee water resources are agricultural producers and recreational anglers. These uses will be directly affected, should the lake become infested with zebra mussels. We employ a probabilistic bioeconomic simulation model to estimate the potential impact of zebra mussels on consumptive water uses, recreational angling, and wetland ecosystem services under alternative public management scenarios. Without public management, the expected net economic impact from zebra m...

  5. Effect of Egg Size on Predation by White-Footed Mice

    Science.gov (United States)

    R. M. DeGraaf; T. J. Maier

    1996-01-01

    We compared predation by wild-trapped, caged white-footed mice (Peromyscus leucopus) on eggs of Japanese Quail (Coturnix coturnix) and Zebra Finches (Poephila guttata) to test the effect of egg size. Nine male and nine female mice were weighed, acclimated to cages for 24 h, and presented with two wicker nests,...

  6. Vocal Communication: Decoding Sexy Songs.

    Science.gov (United States)

    Gahr, Manfred

    2018-04-02

    Male birds communicate sexual motivation via song performance, and receiving females might eventually respond to such 'ornaments'. A new study now shows that female zebra finches have a specialized higher order sensory (forebrain) region that preferably responds to the males' mating songs. Copyright © 2018 Elsevier Ltd. All rights reserved.

  7. A southern African origin and cryptic structure in the highly mobile plains zebra.

    Science.gov (United States)

    Pedersen, Casper-Emil T; Albrechtsen, Anders; Etter, Paul D; Johnson, Eric A; Orlando, Ludovic; Chikhi, Lounes; Siegismund, Hans R; Heller, Rasmus

    2018-03-01

    The plains zebra (Equus quagga) is an ecologically important species of the African savannah. It is also one of the most numerous and widely distributed ungulates, and six subspecies have been described based on morphological variation. However, the within-species evolutionary processes have been difficult to resolve due to its high mobility and a lack of consensus regarding the population structure. We obtained genome-wide DNA polymorphism data from more than 167,000 loci for 59 plains zebras from across the species range, encompassing all recognized extant subspecies, as well as three mountain zebras (Equus zebra) and three Grevy's zebras (Equus grevyi). Surprisingly, the population genetic structure does not mirror the morphology-based subspecies delineation, underlining the dangers of basing management units exclusively on morphological variation. We use demographic modelling to provide insights into the past phylogeography of the species. The results identify a southern African location as the most likely source region from which all extant populations expanded around 370,000 years ago. We show evidence for inclusion of the extinct and phenotypically divergent quagga (Equus quagga quagga) in the plains zebra variation and reveal that it was less divergent from the other subspecies than the northernmost (Ugandan) extant population.

  8. Bioaccumulation of pathogenic bacteria and amoeba by zebra mussels and their presence in watercourses.

    Science.gov (United States)

    Mosteo, R; Goñi, P; Miguel, N; Abadías, J; Valero, P; Ormad, M P

    2016-01-01

    Dreissena polymorpha (the zebra mussel) has been invading freshwater bodies in Europe since the beginning of the nineteenth century. Filter-feeding organisms can accumulate and concentrate both chemical and biological contaminants in their tissues. Therefore, zebra mussels are recognized as indicators of freshwater quality. In this work, the capacity of the zebra mussel to accumulate human pathogenic bacteria and protozoa has been evaluated and the sanitary risk associated with their presence in surface water has also been assessed. The results show a good correlation between the pathogenic bacteria concentration in zebra mussels and in watercourses. Zebra mussels could therefore be used as an indicator of biological contamination. The bacteria (Escherichia coli, Enterococcus spp., Pseudomonas spp., and Salmonella spp.) and parasites (Cryptosporidium oocysts and free-living amoebae) detected in these mussels reflect a potential sanitary risk in water.

  9. IMPACT OF WATER TEMPERATURE ON ZEBRA MUSSEL MORTALITY

    Energy Technology Data Exchange (ETDEWEB)

    Daniel P. Molloy

    2002-08-07

    These tests conducted this past quarter have indicated that the bacterium Pseudomonas fluorescens strain CL0145A is effective at killing zebra mussels at water temperatures ranging from 7 to 23 C. Percent kill will likely be somewhat lower at very low temperatures, e.g., 7 C, but even at such low temperatures high mussel kill can still be achieved (>70% kill). This is significant because the development of a zebra mussel control method that is efficacious in such a wide range of temperatures broadens its usefulness as a potential commercial product.

  10. Zebra Mussel Research Technical Notes. Impacts of Zebra Mussel Infestations on Water Quality. Section 1 - Environmental Testing

    National Research Council Canada - National Science Library

    Ashby, Steven

    1998-01-01

    ..., and sediment quality. The purpose of this technical note describes potential changes in water quality as a result of zebra mussel infestations in aquatic systems, based on a review of the literature...

  11. Journal of Biosciences | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    The distribution of acetylcholinesterase (AChE) in the central vocal control nuclei of the zebra finch was studied using enzyme histochemistry. AChE fibres and cells are intensely labelled in the forebrain nucleus area X, strongly labelled in high vocal centre (HVC) perikarya, and moderately to lightly labelled in the somata ...

  12. Zebra Mussel Chemical Control Guide.

    Science.gov (United States)

    2000-01-01

    are 3 to 5 years. Zebra mussels are filter feeders, opening their shells to allow ingestion of particulates. When their sensitive chemoreceptors alert...used for oxidation of iron and manganese and to correct taste and odor problems in treated water because of its ability to produce oxidation reactions

  13. Naris deformation in Darwin’s finches: Experimental and historical evidence for a post-1960s arrival of the parasite Philornis downsi

    Directory of Open Access Journals (Sweden)

    Sonia Kleindorfer

    2016-07-01

    Full Text Available The rate of evolution depends on the strength of selection, which may be particularly strong for introduced parasites and their naive hosts. Because natural selection acts on phenotypes and because parasites can alter host phenotype, one fruitful starting point to measure the impact of novel pathogens is to quantify parasite-induced changes to host phenotype. Our study system is Darwin’s finches on Floreana Island, Galápagos Archipelago, and the virulent fly larvae of Philornis downsi that were first discovered in Darwin’s finch nests in 1997. We use an experimental approach and measure host phenotype in parasitized and parasite-free chicks in Darwin’s small ground finch (Geospiza fuliginosa. Beak size did not differ between the two treatment groups, but naris size was 106% larger in parasitized chicks (∼3.3 mm versus parasite-free chicks (∼1.6 mm. To test if P. downsi was present prior to the 1960s, we compared naris size in historical (1899–1962 and contemporary birds (2004–2014 on Floreana Island in small ground finches (G. fuliginosa and medium tree finches (Camarhynchus pauper. Contemporary Darwin’s finches had significantly larger naris size (including extreme deformation, whereas historical naris size was both smaller and less variable. These findings provide the first longitudinal analysis for the extent of P. downsi-induced change to host naris size and show that Darwin’s finches, prior to the 1960s, were not malformed. Thus natural selection on altered host phenotype as a consequence of P. downsi parasitism appears to be contemporary and novel.

  14. Zebra mussel control using acoustic energy

    International Nuclear Information System (INIS)

    Tiller, G.W.; Gaucher, T.A.; Menezes, J.K.; Dolat, S.W.

    1992-01-01

    A practical and economical device or method that reduces zebra mussel colonization without detrimental side effects is highly desirable. An ideal method is one that could be installed near, on, or in existing raw water intakes and conduits. It must have a known effect that is limited to a defined area, should have maximum effects on a targeted species, and preferably have a low life cycle cost than the current alternative methods of control and maintenance. Underwater sound could be such a desirable solution, if found to be an effective control measure for zebra mussels. Although sound most often applies specifically to acoustic energy that is audible to humans, 20 Hertz (Hz) to 20 kiloHertz (kHz), in this report we will use the terms sound and acoustic to include acoustic energy between 100 Hz and 100 MegaHertz (MHz). This research on zebra mussel biofouling is designed to effect the early developmental stages in the life cycle of Dreissena polymorpha (Pallas). Vulnerable stages in the development of D. polymorpha that might yield to site-specific acoustic deterrence measures include the free-swimming larval veliger stage, the postveliger pre-attachment demersal stage, and the immediate post-attachment stage. The proposed applications include surface treatment to prevent, reduce or eliminate colonization on underwater structures, and the stream treatment to reduce or eliminate (destroy) mussel larvae entrained in a moving volume of water

  15. Sex Reversal and Comparative Data Undermine the W Chromosome and Support Z-linked DMRT1 as the Regulator of Gonadal Sex Differentiation in Birds.

    Science.gov (United States)

    Hirst, Claire E; Major, Andrew T; Ayers, Katie L; Brown, Rosie J; Mariette, Mylene; Sackton, Timothy B; Smith, Craig A

    2017-09-01

    The exact genetic mechanism regulating avian gonadal sex differentiation has not been completely resolved. The most likely scenario involves a dosage mechanism, whereby the Z-linked DMRT1 gene triggers testis development. However, the possibility still exists that the female-specific W chromosome may harbor an ovarian determining factor. In this study, we provide evidence that the universal gene regulating gonadal sex differentiation in birds is Z-linked DMRT1 and not a W-linked (ovarian) factor. Three candidate W-linked ovarian determinants are HINTW, female-expressed transcript 1 (FET1), and female-associated factor (FAF). To test the association of these genes with ovarian differentiation in the chicken, we examined their expression following experimentally induced female-to-male sex reversal using the aromatase inhibitor fadrozole (FAD). Administration of FAD on day 3 of embryogenesis induced a significant loss of aromatase enzyme activity in female gonads and masculinization. However, expression levels of HINTW, FAF, and FET1 were unaltered after experimental masculinization. Furthermore, comparative analysis showed that FAF and FET1 expression could not be detected in zebra finch gonads. Additionally, an antibody raised against the predicted HINTW protein failed to detect it endogenously. These data do not support a universal role for these genes or for the W sex chromosome in ovarian development in birds. We found that DMRT1 (but not the recently identified Z-linked HEMGN gene) is male upregulated in embryonic zebra finch and emu gonads, as in the chicken. As chicken, zebra finch, and emu exemplify the major evolutionary clades of birds, we propose that Z-linked DMRT1, and not the W sex chromosome, regulates gonadal sex differentiation in birds. Copyright © 2017 Endocrine Society.

  16. Differences in number and distribution of striatal calbindin medium spiny neurons between a vocal-learner (Melopsittacus undulatus and a non-vocal learner bird (Colinus virginianus

    Directory of Open Access Journals (Sweden)

    Elena eGarcia-Calero

    2013-12-01

    Full Text Available Striatal projecting neurons, known as medium spiny neurons (MSNs, segregate into two compartments called matrix and striosome in the mammalian striatum. The matrix domain is characterized by the presence of calbindin immunopositive (CB+ MSNs, not observed in the striosome subdivision. The existence of a similar CB+ MSN population has recently been described in two striatal structures in male zebra finch (a vocal learner bird: the striatal capsule and the Area X, a nucleus implicated in song learning. Female zebra finches show a similar pattern of CB+ MSNs than males in the developing striatum but loose these cells in juveniles and adult stages. In the present work we analyzed the existence and allocation of CB+MSNs in the striatal domain of the vocal learner bird budgerigar (representative of psittaciformes order and the non-vocal learner bird quail (representative of galliformes order. We studied the co-localization of CB protein with FoxP1, a transcription factor expressed in vertebrate striatal MSNs. We observed CB+ MSNs in the medial striatal domain of adult male and female budgerigars, although this cell type was missing in the potentially homologous nucleus for Area X in budgerigar. In quail, we observed CB+ cells in the striatal domain at developmental and adult stages but they did not co-localize with the MSN marker FoxP1. We also described the existence of the CB+ striatal capsule in budgerigar and quail and compared these results with the CB+ striatal capsule observed in juvenile zebra finches. Together, these results point out important differences in CB+MSN distribution between two representative species of vocal learner and non-vocal learner avian orders (respectively the budgerigar and the quail, but also between close vocal learner bird families.

  17. Predation and physical environment structure the density and population size structure of zebra mussels

    OpenAIRE

    Naddafi, Rahmat; Pettersson, Kurt; Eklöv, Peter

    2010-01-01

    The zebra mussel (Dreissena polymorpha) provides one example of successful invaders in novel environments. However, little attention has been devoted to exploring the factors regulating zebra mussel density and population size structure at the local scale. We tested effects of physicochemical factors and fish predation on the density of zebra mussels at several sites and between years in a natural lake. Water depth and roach (Rutilus rutilus) density were the most important variables affectin...

  18. Halicephalobus gingivalis (Nematoda) infection in a Grevy's zebra (Equus grevyi).

    Science.gov (United States)

    Isaza, R; Schiller, C A; Stover, J; Smith, P J; Greiner, E C

    2000-03-01

    A 6-yr-old female Grevy's zebra (Equus grevyi) with a disseminated rhabditiform nematode infection is described. Antemortem clinical signs were limited to blindness and abnormal behavior believed to be caused by a recurrent nematode-induced uveitis. Histologic examination of the kidneys, heart, eyes, uterus, and lymph nodes revealed granulomas containing multiple sections of rhabditiform nematodes. Most of the recovered nematodes were larval stages with only a few adult females noted. The adults measured 243-297 microm x 11-16 microm (x = 269 x 14 microm). The distinctive rhabditiform esophagi had corpus:isthmus:bulb proportions of 19:11:5. On the basis of adult morphology, the nematode was identified as Halicephalobus gingivalis. This is the first report of this parasite in a zebra and indicates that this parasitic granulomatous disease should be considered in zebras with neurologic disease.

  19. Hemispheric dominance underlying the neural substrate for learned vocalizations develops with experience.

    Science.gov (United States)

    Chirathivat, Napim; Raja, Sahitya C; Gobes, Sharon M H

    2015-06-22

    Many aspects of song learning in songbirds resemble characteristics of speech acquisition in humans. Genetic, anatomical and behavioural parallels have most recently been extended with demonstrated similarities in hemispheric dominance between humans and songbirds: the avian higher order auditory cortex is left-lateralized for processing song memories in juvenile zebra finches that already have formed a memory of their fathers' song, just like Wernicke's area in the left hemisphere of the human brain is dominant for speech perception. However, it is unclear if hemispheric specialization is due to pre-existing functional asymmetry or the result of learning itself. Here we show that in juvenile male and female zebra finches that had never heard an adult song before, neuronal activation after initial exposure to a conspecific song is bilateral. Thus, like in humans, hemispheric dominance develops with vocal proficiency. A left-lateralized functional system that develops through auditory-vocal learning may be an evolutionary adaptation that could increase the efficiency of transferring information within one hemisphere, benefiting the production and perception of learned communication signals.

  20. Development and validation of a house finch interleukin-1β (HfIL-1β) ELISA system.

    Science.gov (United States)

    Kim, Sungwon; Park, Myeongseon; Leon, Ariel E; Adelman, James S; Hawley, Dana M; Dalloul, Rami A

    2017-08-30

    A unique clade of the bacterium Mycoplasma gallisepticum (MG), which causes chronic respiratory disease in poultry, has resulted in annual epidemics of conjunctivitis in North American house finches since the 1990s. Currently, few immunological tools have been validated for this songbird species. Interleukin-1β (IL-1β) is a prototypic multifunctional cytokine and can affect almost every cell type during Mycoplasma infection. The overall goal of this study was to develop and validate a direct ELISA assay for house finch IL-1β (HfIL-1β) using a cross-reactive chicken antibody. A direct ELISA approach was used to develop this system using two different coating methods, carbonate and dehydration. In both methods, antigens (recombinant HfIL-1b or house finch plasma) were serially diluted in carbonate-bicarbonate coating buffer and either incubated at 4 °C overnight or at 60 °C on a heating block for 2 hr. To generate the standard curve, rHfIL-1b protein was serially diluted at 0, 3, 6, 9, 12, 15, 18, 21, and 24 ng/mL. Following blocking and washing, anti-chicken IL-1b polyclonal antibody was added, plates were later incubated with detecting antibodies, and reactions developed with tetramethylbenzidine solution. A commercially available anti-chicken IL-1β (ChIL-1β) polyclonal antibody (pAb) cross-reacted with house finch plasma IL-1β as well as bacterially expressed recombinant house finch IL-1β (rHfIL-1β) in immunoblotting assays. In a direct ELISA system, rHfIL-1β could not be detected by an anti-ChIL-1β pAb when the antigen was coated with carbonate-bicarbonate buffer at 4°C overnight. However, rHfIL-1β was detected by the anti-ChIL-1β pAb when the antigen was coated using a dehydration method by heat (60°C). Using the developed direct ELISA for HfIL-1β with commercial anti-ChIL-1β pAb, we were able to measure plasma IL-1β levels from house finches. Based on high amino acid sequence homology, we hypothesized and demonstrated cross-reactivity of

  1. ZebraZoom: an automated program for high-throughput behavioral analysis and categorization

    Science.gov (United States)

    Mirat, Olivier; Sternberg, Jenna R.; Severi, Kristen E.; Wyart, Claire

    2013-01-01

    The zebrafish larva stands out as an emergent model organism for translational studies involving gene or drug screening thanks to its size, genetics, and permeability. At the larval stage, locomotion occurs in short episodes punctuated by periods of rest. Although phenotyping behavior is a key component of large-scale screens, it has not yet been automated in this model system. We developed ZebraZoom, a program to automatically track larvae and identify maneuvers for many animals performing discrete movements. Our program detects each episodic movement and extracts large-scale statistics on motor patterns to produce a quantification of the locomotor repertoire. We used ZebraZoom to identify motor defects induced by a glycinergic receptor antagonist. The analysis of the blind mutant atoh7 revealed small locomotor defects associated with the mutation. Using multiclass supervised machine learning, ZebraZoom categorized all episodes of movement for each larva into one of three possible maneuvers: slow forward swim, routine turn, and escape. ZebraZoom reached 91% accuracy for categorization of stereotypical maneuvers that four independent experimenters unanimously identified. For all maneuvers in the data set, ZebraZoom agreed with four experimenters in 73.2–82.5% of cases. We modeled the series of maneuvers performed by larvae as Markov chains and observed that larvae often repeated the same maneuvers within a group. When analyzing subsequent maneuvers performed by different larvae, we found that larva–larva interactions occurred as series of escapes. Overall, ZebraZoom reached the level of precision found in manual analysis but accomplished tasks in a high-throughput format necessary for large screens. PMID:23781175

  2. Laterality of suckling behaviour in three zebra species.

    Science.gov (United States)

    Pluháček, Jan; Olléová, Michaela; Bartošová, Jitka; Pluháčková, Jana; Bartoš, Luděk

    2013-01-01

    Although side preference while suckling is an easily characterised lateralised behaviour, few studies have been conducted. We observed laterality in suckling behaviour in three captive zebra species to test two hypotheses: laterality affected by the foal (motor laterality) and laterality affected by the mother. In total we observed 35 foals of Grevy's, plains, and mountain zebra in two zoos and recorded 5128 successful suckling bouts and 9095 unsuccessful suckling attempts. At the population level the only factor affecting side preference of suckling bouts and attempts was the identity of the individual foal. Ten foals showed individual preferences: seven foals preferred suckling from the left side of the mother, three preferred suckling from the right side of the mother. The individual preferences increased with increasing age of the foal. Only one foal was refused more often from the opposite side than the preferred side used for suckling whereas three other foals were refused from the preferred side. Foals that preferred suckling either from left or right side were refused by the mare more often than foals which showed non-preference. Thus lateral preferences in suckling behaviour of zebra foals seem to be in line with the motor laterality hypotheses.

  3. Uptake of dissolved organic carbon and trace elements by zebra mussels

    Science.gov (United States)

    Roditi, Hudson A.; Fisher, Nicholas S.; Sañudo-Wilhelmy, Sergio A.

    2000-09-01

    Zebra mussels (Dreissena polymorpha) are widespread and abundant in major freshwater ecosystems in North America, even though the phytoplankton food resources in some of these systems seem to be too low to sustain them. Because phytoplankton biomass is greatly depleted in ecosystems with large D. polymorpha populations and bacteria do not seem to be an important food source for this species, exploitation of alternative carbon sources may explain the unexpected success of D. polymorpha in such environments. Here we examine the possibility that absorption of dissolved organic carbon (DOC) from water could provide a nutritional supplement to zebra mussels. We find that mussels absorb 14C-labelled DOC produced by cultured diatoms with an efficiency of 0.23%; this indicates that DOC in natural waters could contribute up to 50% of the carbon demand of zebra mussels. We also find that zebra mussels absorb some dissolved metals that have been complexed by the DOM; although absorption of dissolved selenium was unaffected by DOC, absorption of dissolved cadmium, silver and mercury by the mussels increased 32-, 8.7- and 3.6-fold, respectively, in the presence of high-molecular-weight DOC.

  4. Repeatability of host female and male aggression towards a brood parasite

    Czech Academy of Sciences Publication Activity Database

    Trnka, A.; Požgayová, Milica; Samaš, P.; Honza, Marcel

    2013-01-01

    Roč. 119, č. 10 (2013), s. 907-917 ISSN 0179-1613 R&D Projects: GA ČR(CZ) GAP506/12/2404 Institutional support: RVO:68081766 Keywords : Cuckoo Cuculus canorus * Great reed warblers * Nest defense * Behavioral syndromes * Plumage polymorphism * Enemy recognition * Potential hosts * Practical guide * Zebra finches Subject RIV: EG - Zoology Impact factor: 1.556, year: 2013

  5. Putative clinical piroplasmosis in a Burchell's zebra (Equus quagga burchelli).

    Science.gov (United States)

    Lampen, F; Bhoora, R; Collins, N E; Penzhorn, B L

    2009-12-01

    A 10-year-old tame zebra gelding was presented after suffering from lethargy, nervousness, reported anaemia and icterus as well as a decreased appetite. These symptoms were seen over some months, with changing severity. The animal was immobilised, treated, and blood specimens were submitted for haematology and biochemistry. This report describes molecular characterisation of Theileria equi recovered from this animal, as well as the clinical findings, treatment and historical relevance of piroplasmosis in zebra in southern Africa.

  6. Factorial microarray analysis of zebra mussel (Dreissena polymorpha: Dreissenidae, Bivalvia adhesion

    Directory of Open Access Journals (Sweden)

    Faisal Mohamed

    2010-05-01

    Full Text Available Abstract Background The zebra mussel (Dreissena polymorpha has been well known for its expertise in attaching to substances under the water. Studies in past decades on this underwater adhesion focused on the adhesive protein isolated from the byssogenesis apparatus of the zebra mussel. However, the mechanism of the initiation, maintenance, and determination of the attachment process remains largely unknown. Results In this study, we used a zebra mussel cDNA microarray previously developed in our lab and a factorial analysis to identify the genes that were involved in response to the changes of four factors: temperature (Factor A, current velocity (Factor B, dissolved oxygen (Factor C, and byssogenesis status (Factor D. Twenty probes in the microarray were found to be modified by one of the factors. The transcription products of four selected genes, DPFP-BG20_A01, EGP-BG97/192_B06, EGP-BG13_G05, and NH-BG17_C09 were unique to the zebra mussel foot based on the results of quantitative reverse transcription PCR (qRT-PCR. The expression profiles of these four genes under the attachment and non-attachment were also confirmed by qRT-PCR and the result is accordant to that from microarray assay. The in situ hybridization with the RNA probes of two identified genes DPFP-BG20_A01 and EGP-BG97/192_B06 indicated that both of them were expressed by a type of exocrine gland cell located in the middle part of the zebra mussel foot. Conclusions The results of this study suggested that the changes of D. polymorpha byssogenesis status and the environmental factors can dramatically affect the expression profiles of the genes unique to the foot. It turns out that the factorial design and analysis of the microarray experiment is a reliable method to identify the influence of multiple factors on the expression profiles of the probesets in the microarray; therein it provides a powerful tool to reveal the mechanism of zebra mussel underwater attachment.

  7. Factorial microarray analysis of zebra mussel (Dreissena polymorpha: Dreissenidae, Bivalvia) adhesion.

    Science.gov (United States)

    Xu, Wei; Faisal, Mohamed

    2010-05-28

    The zebra mussel (Dreissena polymorpha) has been well known for its expertise in attaching to substances under the water. Studies in past decades on this underwater adhesion focused on the adhesive protein isolated from the byssogenesis apparatus of the zebra mussel. However, the mechanism of the initiation, maintenance, and determination of the attachment process remains largely unknown. In this study, we used a zebra mussel cDNA microarray previously developed in our lab and a factorial analysis to identify the genes that were involved in response to the changes of four factors: temperature (Factor A), current velocity (Factor B), dissolved oxygen (Factor C), and byssogenesis status (Factor D). Twenty probes in the microarray were found to be modified by one of the factors. The transcription products of four selected genes, DPFP-BG20_A01, EGP-BG97/192_B06, EGP-BG13_G05, and NH-BG17_C09 were unique to the zebra mussel foot based on the results of quantitative reverse transcription PCR (qRT-PCR). The expression profiles of these four genes under the attachment and non-attachment were also confirmed by qRT-PCR and the result is accordant to that from microarray assay. The in situ hybridization with the RNA probes of two identified genes DPFP-BG20_A01 and EGP-BG97/192_B06 indicated that both of them were expressed by a type of exocrine gland cell located in the middle part of the zebra mussel foot. The results of this study suggested that the changes of D. polymorpha byssogenesis status and the environmental factors can dramatically affect the expression profiles of the genes unique to the foot. It turns out that the factorial design and analysis of the microarray experiment is a reliable method to identify the influence of multiple factors on the expression profiles of the probesets in the microarray; therein it provides a powerful tool to reveal the mechanism of zebra mussel underwater attachment.

  8. Zebra mussels (Dreissena polymorpha) in Ireland, AFLP-fingerprinting and boat traffic both indicate an origin from Britain

    NARCIS (Netherlands)

    Pollux, B.J.A.; Minchin, D.; Van der Velde, G.; Van Alen, T.; Moon-Van der Staay, S.Y.; Hackstein, J.

    2003-01-01

    The zebra mussel (Dreissena polymorpha) is an aquatic nuisance species that invaded Ireland around 1994. We studied the invasion of the zebra mussel combining field surveys and genetic studies, to determine the origin of invasion and the vector of introduction. Field surveys showed that live zebra

  9. Modelling the effects of diving ducks on zebra mussels Dreissena polymorpha in lakes

    NARCIS (Netherlands)

    Nes, van E.H.; Noordhuis, R.; Lammens, E.H.R.R.; Portielje, R.; Reeze, B.; Peeters, E.T.H.M.

    2008-01-01

    An individual-based model describing the growth of zebra mussels (Dreissena polymorpha) is presented. The model is spatially explicit and predicts length¿frequency distributions of zebra mussels. The parameters and model inputs with the strongest effect on the model outcomes were identified using a

  10. Evaluation of several chemical disinfectants for removing zebra mussels from unionid mussels

    Science.gov (United States)

    Waller, D.L.; Fisher, S.W.

    1998-01-01

    We evaluated the safety and effectiveness of chemical treatments for killing veliger and juvenile stages of the zebra mussel Dreissena polymorpha attached to unionid mussels. Static toxicity tests were conducted on eight unionid mussel species with common aquaculture chemicals (benzalkonium chloride, formalin, hydrogen peroxide, calcium chloride, potassium chloride, and sodium chloride). The concentration and duration of each chemical treatment tested had previously been found to kill zebra mussel veligers and juveniles. Several species (e.g., Elliptio dilatata, Lampsilis cardium, and Lasmigona complanata) incurred less than 10% mortality in chloride salt treatments, while in other species (e.g., Obliquaria reflexa and Leptodea fragilis) mortality varied greatly among treatment regimes. Treatments with benzalkonium chloride, formalin, and hydrogen peroxide were less than 90% effective on juvenile stages of zebra mussels and, therefore, were ruled out after preliminary trials. Limited application of specific chemical treatments may be feasible for more tolerant species; however, effective disinfection of unionid shells will require the use of chemical treatment followed by a quarantine period to completely remove zebra mussel larvae and juveniles.

  11. Monitoring of zebra mussels in the Shannon-Boyle navigation, other

    OpenAIRE

    Minchin, D.; Lucy, F.; Sullivan, M.

    2002-01-01

    The zebra mussel (Dreissena polymorpha) population has been closely monitored in Ireland following its discovery in 1997. The species has spread from lower Lough Derg, where it was first introduced, to most of the navigable areas of the Shannon and other interconnected navigable waters. This study took place in the summers of 2000 and 2001 and investigated the relative abundance and biomass of zebra mussels found in the main navigations of the Shannon and elsewhere in rivers, canals and lakes...

  12. Newspaper Coverage of Zebra Mussels in North America : A Case of "Afghanistanism"?

    OpenAIRE

    Roush, Donny; Fortner, Rosanne

    1996-01-01

    Few environmental issues have arisen so abruptly, spread so rapidly, and been so clearly linked to human activity as has the introduction of nonindigenous zebra mussels to the surface freshwater of North America. This research examines communication patterns in information about zebra mussels as an example of how the mass media deal with threats to the environment.

  13. Molecular phylogeny of equine herpesvirus 1 isolates from onager, zebra and Thomson's gazelle.

    Science.gov (United States)

    Ghanem, Y M; Fukushi, H; Ibrahim, E S M; Ohya, K; Yamaguchi, T; Kennedy, M

    2008-01-01

    Viruses related to equine herpesvirus type 1 (EHV-1) were isolated from an aborted fetus of an onager (Equus hemionus) in 1984, an aborted fetus of Grevy's zebra (Equus grevyi) in 1984 and a Thomson's gazelle (Gazella thomsoni) with nonsuppurative encephalitis in 1996, all in the USA. The mother of the onager fetus and the gazelle were kept near plains zebras (Equus burchelli). In phylogenetic trees based on the nucleotide sequences of the genes for glycoproteins B (gB), I (gI), and E (gE), and teguments including ORF8 (UL51), ORF15 (UL45), and ORF68 (US2), the onager, Grevy's zebra and gazelle isolates formed a genetic group that was different from several horse EHV-1 isolates. Within this group, the onager and gazelle isolates were closely related, while the Grevy's zebra isolate was distantly related to these two isolates. The epizootiological origin of the viruses is discussed.

  14. Recognition and Reconstruction of Zebra Crossings on Roads from Mobile Laser Scanning Data

    Directory of Open Access Journals (Sweden)

    Lin Li

    2016-07-01

    Full Text Available Zebra crossings provide guidance and warning to pedestrians and drivers, thereby playing an important role in traffic safety management. Most previous studies have focused on detecting zebra stripes but have not provided full information about the areas, which is critical to both driver assistance systems and guide systems for blind individuals. This paper presents a stepwise procedure for recognizing and reconstructing zebra crossings using mobile laser scanning data. First, we propose adaptive thresholding based on road surface partitioning to reduce the impact of intensity unevenness and improve the accuracy of road marking extraction. Then, dispersion degree filtering is used to reduce the noise. Finally, zebra stripes are recognized according to the rectangular feature and fixed size, which is followed by area reconstruction according to arrangement patterns. We test our method on three datasets captured by an Optech Lynx mobile mapping system. The total recognition rate of 90.91% demonstrates the effectiveness of the method.

  15. Process in Developing Zebra fish Laboratory at Malaysian Nuclear Agency for Toxicology Studies

    International Nuclear Information System (INIS)

    Fazliana Mohd Saaya; Mohd Noor Hidayat Adenan; Anee Suryani Sued

    2015-01-01

    Toxicology is a branch of the very important especially in determining the safety and effectiveness of herbal products to avoid any side effects to the user. Currently, toxicity tests conducted in the laboratory is testing the toxicity of shrimp, tests on cell cultures and experimental animal tests on the rats. One of the most recent exam easier and can reduce the use of experimental rats was testing on zebra fish fish. Fish zebra fish Danio rerio, suitable for the study of toxicity, teratogenicity, genetic, oncology and neurobiology. Zebra fish system of aquarium fish zebra fish system has been in Nuclear Malaysia since 2013 but has not yet fully operational due to several factors and is in the process of moving into a new laboratory which systematically and in accordance with the enabling environment for care. The development of a new fully equipped laboratory is expected to benefit all for use in research. (author)

  16. Use of on-site refugia to protect unionid populations from zebra mussel-induced mortality

    Science.gov (United States)

    Nichols, S. Jerrine; Black, M. Glen; Allen, Jeffrey D.

    2000-01-01

    Protecting unionid populations as zebra mussels spread into inland waterways has relied mainly on relocating at-risk animals into aquaculture facilities. While such relocations are the only viable management technique for some populations, facility availability is limited, leaving many unionids facing extirpation. Another management strategy is in-situ protection either by enhancing natural refugia or by creating managed refugia. We have reviewed all reports of natural refugia and found that refugia for unionids can be found in many areas. There are many habitats where zebra mussel colonization has been limited, or of a temporary nature. Within zebra mussel infested areas, unionid communities continue to survive in some shallow water sites such as estuaries, deltas, and lake-connected wetlands. Managed refugia can be created in areas where natural refugia do not exist. We present a case study on recent efforts to create refugia in an area with rapidly expanding zebra mussel populations. Preliminary analysis of unionid body condition indicates that removal of encrusted zebra mussels only once a year can improve unionid condition factors and decrease mortality. Natural and managed refugia can provide an additional conservation management option in some areas.

  17. Effects of the exotic zebra mussel (Dreissena polymorpha) on metal cycling in Lake Erie

    International Nuclear Information System (INIS)

    Klerks, P.L.; Fraleigh, P.C.; Lawniczak, J.E.

    1997-01-01

    This research demonstrated the impact of high densities of the zebra mussel (Dreissena polymorpha) on the cycling of copper, nickel, and zinc in a lake environment. Experiments with mussels on sedimentation traps in western Lake Erie and with mussels in flow-through tanks receiving Lake Erie water showed that zebra mussels remove metals from the water column, incorporate metals in their tissues, and deposit metals on the lake bottom. Removal of metals from the water column was estimated at 10-17%·day -1 of the amounts present. This material was largely deposited on the lake bottom; zebra mussels more than doubled the rate at which metals were being added to the lake bottom. Metal biodeposition rates were extremely high (e.g., 50 mg Zn·m -2 ·day -1 ) in high-turbidity areas with elevated metal levels. Two factors contributed to metal biodeposition by zebra mussels. First, their production of feces and pseudofeces increased the rate at which suspended matter was being added to the sediment (accounting for 92% of the increased metal biodeposition). Second, the material coming out of suspension had higher metal concentrations when zebra mussels were present (constituting 8% of the increased biodeposition). (author)

  18. Habitat engineering by the invasive zebra mussel Dreissena polymorpha (Pallas) in a boreal coastal lagoon: impact on biodiversity

    Science.gov (United States)

    Zaiko, Anastasija; Daunys, Darius; Olenin, Sergej

    2009-03-01

    Habitat engineering role of the invasive zebra mussel Dreissena polymorpha (Pallas) was studied in the Curonian lagoon, a shallow water body in the SE Baltic. Impacts of live zebra mussel clumps and its shell deposits on benthic biodiversity were differentiated and referred to unmodified (bare) sediments. Zebra mussel bed was distinguished from other habitat types by higher benthic invertebrate biomass, abundance, and species richness. The impact of live mussels on biodiversity was more pronounced than the effect of shell deposits. The structure of macrofaunal community in the habitats with >103 g/m2 of shell deposits devoid of live mussels was similar to that found within the zebra mussel bed. There was a continuous shift in species composition and abundance along the gradient ‘bare sediments—shell deposits—zebra mussel bed’. The engineering impact of zebra mussel on the benthic community became apparent both in individual patches and landscape-level analyses.

  19. Strategies to control zebra mussel fouling at Kewaunee Nuclear Power Plant

    International Nuclear Information System (INIS)

    Schwartz, D.; Kasper, J.R.; Pisani, W.

    1992-01-01

    The zebra mussel, Dreissena polymorpha, is currently infesting the Great Lakes. First discovered in Lake St. Clair, it is now widespread in Lakes Erie and Ontario. The initial efforts relating to zebra mussel control at Wisconsin Public Service Corporation's (WPSC) Kewaunee Nuclear Power Plant (KNPP) precipitated from the Nuclear Regulatory Commission's (NRC) Generic Letter 89-13 regarding fouling of service water (SW) systems at nuclear power plants. In the summer of 1990, Stone and Webster Engineering Corporation (Stone and Webster) was contracted to perform an evaluation of known problems within the SW system. The purposes of the study were to evaluate the actual and potential magnitude of these problems, to evaluate corrective actions to resolve the problems, and to prepare recommendations which would adequately address the issues. Two of the recommendations of this study were to continue a zebra mussel monitoring program which WPSC had already implemented and to evaluate various biocide injection programs should one be required for zebra mussel control. The concern of utilities operating power stations which use waters infested with zebra mussels as their source of cooling and/or makeup water is that mussels (both adults and veligers) will enter plant water systems and foul piping and heat exchangers. This type of fouling can restrict flow through piping, process equipment, and heat exchangers. This type of fouling can restrict flow through piping, process equipment, and heat exchangers, thereby increasing head losses and reducing heat transfer capabilities. The greatest concern in that fouling of this type is within safety-related piping and equipment that are components of service water systems at nuclear power plants

  20. Seasonal effects of the zebra mussel (Dreissena polymorpha) on sediment denitrification rates in Pool 8 of the Upper Mississippi River

    Science.gov (United States)

    Bruesewitz, Denise A.; Tank, Jennifer L.; Bernot, Melody J.; Richardson, William B.; Strauss, Eric A.

    2006-01-01

    Zebra mussels (Dreissena polymorpha) have altered the structure of invaded ecosystems and exhibit characteristics that suggest they may influence ecosystem processes such as nitrogen (N) cycling. We measured denitrification rates seasonally on sediments underlying zebra mussel beds collected from the impounded zone of Navigation Pool 8 of the Upper Mississippi River. Denitrification assays were amended with nutrients to characterize variation in nutrient limitation of denitrification in the presence or absence of zebra mussels. Denitrification rates at zebra mussel sites were high relative to sites without zebra mussels in February 2004 (repeated measures analysis of variance (RM ANOVA), p = 0.005), potentially because of high NO3-N variability from nitrification of high NH4+ zebra mussel waste. Denitrification rates were highest in June 2003 (RM ANOVA, p 3-N concentrations during the study (linear regression, R2 = 0.72, p p ≤ 0.01). Examining how zebra mussels influence denitrification rates will aid in developing a more complete understanding of the impact of zebra mussels and more effective management strategies of eutrophic waters.

  1. Predicting the spread of aquatic invaders: insight from 200 years of invasion by zebra mussels.

    Science.gov (United States)

    Karatayev, Alexander Y; Burlakova, Lyubov E; Mastitsky, Sergey E; Padilla, Dianna K

    2015-03-01

    Understanding factors controlling the introduction and spread of species is crucial to improving the management of both natural populations and introduced species. The zebra mussel, Dreissena polymorpha, is considered the most aggressive freshwater invader in the Northern Hemisphere, and is a convenient model system for invasion biology, offering one of the best aquatic examples for examining the invasion process. We used data on 553 of the 1040 glacial lakes in the Republic of Belarus that were examined for the presence of zebra mussels. We used these data to build, test, and construct modified models to predict the spread of this invader, including selection of important parameters that could limit the spread of this invader. In spite of 200 years of continuous invasion, by 1996, zebra mussels were found in only 16.8% of all lakes studied. Of those lakes without zebra mussels in 1996, 66% were predicted to be susceptible to invasion by zebra mussels in the future, and 33% were predicted to be immune to successful invasion due to their water chemistry. Eighty lakes free of zebra mussels in 1996 were reexamined from 1997 to 2008. Of these, zebra mussels successfully invaded an additional 31 lakes, all of which were classified initially as suitable for zebra mussels; none of the lakes previously classified as unsuitable were invaded. We used the Random Forests classification algorithm with 16 environmental variables to determine the most important factors that differed between invaded lakes and those lakes suitable for invasion that have not yet been invaded. Distance to the nearest infested lakes was found to be the most important variable, followed by the lake area, color, average depth, and concentration of chloride, magnesium, and bicarbonate. This study provides a useful approach for predicting the spread of an invader across a landscape with variable habitat suitability that can be applied to a variety of species and systems.

  2. Zebra Mussel Antifouling Activity of the Marine Natural Product Aaptamine and Analogs

    Science.gov (United States)

    Diers, Jeffrey A.; Bowling, John J.; Duke, Stephen O.; Wahyuono, Subagus; Kelly, Michelle; Hamann, Mark T.

    2016-01-01

    Several aaptamine derivatives were selected as potential zebra mussel (Dreissena polymorpha) antifoulants because of the noteworthy absence of fouling observed on Aaptos sponges. Sponges of the genus Aaptos collected in Manado, Indonesia consistently produce aaptamine-type alkaloids. To date, aaptamine and its derivatives have not been carefully evaluated for their antifoulant properties. Structure–activity relationship studies were conducted using several aaptamine derivatives in a zebra mussel antifouling assay. From these data, three analogs have shown significant antifouling activity against zebra mussel attachment. Aaptamine, isoaaptamine, and the demethylated aaptamine compounds used in the zebra mussel assay produced EC50 values of 24.2, 11.6, and 18.6 μM, respectively. In addition, neither aaptamine nor isoaaptamine produced a phytotoxic response (as high as 300 μM) toward a nontarget organism, Lemna pausicostata, in a 7-day exposure. The use of these aaptamine derivatives from Aaptos sp. as potential environmentally benign antifouling alternatives to metal-based paints and preservatives is significant, not only as a possible control of fouling organisms, but also to highlight the ecological importance of these and similar biochemical defenses. PMID:16718618

  3. DNA adduct measurements in zebra mussels, Dreissena polymorpha, Pallas

    International Nuclear Information System (INIS)

    Le Goff, J.; Gallois, J.; Pelhuet, L.; Devier, M.H.; Budzinski, H.; Pottier, D.; Andre, V.; Cachot, J.

    2006-01-01

    The purpose of this study was to examine PAH accumulation and bulky DNA adduct formation in the digestive gland of zebra mussels exposed in their habitat or in controlled laboratory conditions to complex mixture of PAH. DNA adducts were measured using a 32 P-postlabelling protocol with nuclease P1 enrichment adapted from Reddy and Randerath [Reddy, M.V., Randerath, K., 1986. Nuclease P1-mediated enhancement of sensitivity of 32 P-postlabelling test for structurally diverse DNA adducts. Carcinogenesis 7, 1543-1551]. Specimens collected in the upper part of the Seine estuary were shown to accumulate higher levels of PAH (up to 1.6 μg g -1 dry weight) in comparison to individuals from the reference site (0.053 μg g -1 dry weight). The former exhibited elevated levels of DNA adducts (up to 4.0/10 8 nucleotides) and higher diversity of individual adducts with five distinct spots being specifically detected in individuals originating from the Seine estuary. Zebra mussels exposed for 5 days to 0.01% (v/v) of organic extract of sediment from the Seine estuary were shown to accumulate high amounts of PAH (up to 138 μg g -1 dry weight) but exhibited relatively low levels of DNA adducts. Exposure to benzo[a]pyrene led to a dose-dependent accumulation of B[a]P (up to 7063 μg g -1 dry weight) and a clear induction of DNA adduct formation in the digestive gland of mussels (up to 1.13/10 8 nucleotides). Comparisons with other bivalves exposed to the same model PAH, revealed similar levels of adducts and comparable adduct profiles with a main adduct spot and a second faint one. This study clearly demonstrated that zebra mussels are able to biotransform B[a]P and probably other PAH into reactive metabolites with DNA-binding activity. This work also demonstrated the applicability of the nuclease P1 enhanced 32 P-postlabelling method for bulky adduct detection in the digestive gland of zebra mussels. DNA adduct measurement in zebra mussels could be a suitable biomarker to monitor

  4. DNA adduct measurements in zebra mussels, Dreissena polymorpha, Pallas

    Energy Technology Data Exchange (ETDEWEB)

    Le Goff, J. [GRECAN, UPRES EA-1772, University of Caen, Caen (France); Gallois, J. [Laboratory F. Duncombe, Conseil General du Calvados, Caen (France); Pelhuet, L. [LPTC, UMR-5472 CNRS, University Bordeaux I, Bordeaux (France); Devier, M.H. [LPTC, UMR-5472 CNRS, University Bordeaux I, Bordeaux (France); Budzinski, H. [LPTC, UMR-5472 CNRS, University Bordeaux I, Bordeaux (France); Pottier, D. [GRECAN, UPRES EA-1772, University of Caen, Caen (France); Andre, V. [GRECAN, UPRES EA-1772, University of Caen, Caen (France); Cachot, J. [LEMA, UPRES EA-3222, IFRMP 23, University of Le Havre, 25 rue Philippe Lebon, B.P. 540, 76058 Le Havre Cedex (France)]. E-mail: jerome.cachot@univ-lehavre.fr

    2006-08-12

    The purpose of this study was to examine PAH accumulation and bulky DNA adduct formation in the digestive gland of zebra mussels exposed in their habitat or in controlled laboratory conditions to complex mixture of PAH. DNA adducts were measured using a {sup 32}P-postlabelling protocol with nuclease P1 enrichment adapted from Reddy and Randerath [Reddy, M.V., Randerath, K., 1986. Nuclease P1-mediated enhancement of sensitivity of {sup 32}P-postlabelling test for structurally diverse DNA adducts. Carcinogenesis 7, 1543-1551]. Specimens collected in the upper part of the Seine estuary were shown to accumulate higher levels of PAH (up to 1.6 {mu}g g{sup -1} dry weight) in comparison to individuals from the reference site (0.053 {mu}g g{sup -1} dry weight). The former exhibited elevated levels of DNA adducts (up to 4.0/10{sup 8} nucleotides) and higher diversity of individual adducts with five distinct spots being specifically detected in individuals originating from the Seine estuary. Zebra mussels exposed for 5 days to 0.01% (v/v) of organic extract of sediment from the Seine estuary were shown to accumulate high amounts of PAH (up to 138 {mu}g g{sup -1} dry weight) but exhibited relatively low levels of DNA adducts. Exposure to benzo[a]pyrene led to a dose-dependent accumulation of B[a]P (up to 7063 {mu}g g{sup -1} dry weight) and a clear induction of DNA adduct formation in the digestive gland of mussels (up to 1.13/10{sup 8} nucleotides). Comparisons with other bivalves exposed to the same model PAH, revealed similar levels of adducts and comparable adduct profiles with a main adduct spot and a second faint one. This study clearly demonstrated that zebra mussels are able to biotransform B[a]P and probably other PAH into reactive metabolites with DNA-binding activity. This work also demonstrated the applicability of the nuclease P1 enhanced {sup 32}P-postlabelling method for bulky adduct detection in the digestive gland of zebra mussels. DNA adduct measurement in

  5. WINTOF - A program to produce neutron spectra from Zebra time-of-flight experiments

    International Nuclear Information System (INIS)

    Marshall, J.

    1969-06-01

    This report describes a computer program, written for the Winfrith KDF9 computer, which is used to calculate the neutron energy spectrum in the Zebra reactor from neutron time-of-flight measurements using the Zebra Linac. The data requirements for the program are specified and an illustration of the final spectrum is included. (author)

  6. Bioaccumulation of human waterborne protozoa by zebra mussel (Dreissena polymorpha): interest for water biomonitoring.

    Science.gov (United States)

    Palos Ladeiro, M; Aubert, D; Villena, I; Geffard, A; Bigot, A

    2014-01-01

    Cryptosporidium parvum, Giardia duodenalis and Toxoplasma gondii are ubiquitous pathogens, which waterborne transmission has been largely demonstrated. Since they can be found in various watercourses, interactions with aquatic organisms are possible. Protozoan detection for watercourses biomonitoring is currently based on large water filtration. The zebra mussel, Dreissena polymorpha, is a choice biological model in ecotoxicological studies which are already in use to detect chemical contaminations in watercourses. In the present study, the zebra mussel was tested as a new tool for detecting water contamination by protozoa. In vivo exposures were conducted in laboratory experiments. Zebra mussel was exposed to various protozoan concentrations for one week. Detection of protozoa was realized by Taqman real time qPCR. Our experiments evidenced C. parvum, G. duodenalis and T. gondii oocyst bioaccumulation by mussels proportionally to ambient contamination, and significant T. gondii prevalence was observed in muscle tissue. To our knowledge, this is the first study that demonstrates T. gondii oocyst accumulation by zebra mussel. The results from this study highlight the capacity of zebra mussels to reveal ambient biological contamination, and thus to be used as a new effective tool in sanitary biomonitoring of water bodies. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Effects of the exotic zebra mussel (Dreissena polymorpha) on metal cycling in Lake Erie

    Energy Technology Data Exchange (ETDEWEB)

    Klerks, P.L. [Univ. of Southwestern Louisiana, Dept. of Biology, Lafayette, Louisiana (United States)]. E-mail: klerks@usl.edu; Fraleigh, P.C.; Lawniczak, J.E. [Univ. of Toledo, Dept. of Biology, Toledo, Ohio (United States)

    1997-07-15

    This research demonstrated the impact of high densities of the zebra mussel (Dreissena polymorpha) on the cycling of copper, nickel, and zinc in a lake environment. Experiments with mussels on sedimentation traps in western Lake Erie and with mussels in flow-through tanks receiving Lake Erie water showed that zebra mussels remove metals from the water column, incorporate metals in their tissues, and deposit metals on the lake bottom. Removal of metals from the water column was estimated at 10-17%{center_dot}day{sup -1} of the amounts present. This material was largely deposited on the lake bottom; zebra mussels more than doubled the rate at which metals were being added to the lake bottom. Metal biodeposition rates were extremely high (e.g., 50 mg Zn{center_dot}m{sup -2}{center_dot}day{sup -1}) in high-turbidity areas with elevated metal levels. Two factors contributed to metal biodeposition by zebra mussels. First, their production of feces and pseudofeces increased the rate at which suspended matter was being added to the sediment (accounting for 92% of the increased metal biodeposition). Second, the material coming out of suspension had higher metal concentrations when zebra mussels were present (constituting 8% of the increased biodeposition). (author)

  8. Effects of Room-Temperature Ionic Liquids on Zebra Mussels (Dreissena polymorpha)

    Science.gov (United States)

    Costello, D. M.; Bernot, R. J.; Lamberti, G. A.

    2005-05-01

    Zebra mussels (Dreissena polymorpha) are exotic bivalves that are widely distributed in eastern North America. We propose that this nuisance organism could serve as a model species for studies of aquatic toxicology. We tested zebra mussels response to room-temperature ionic liquids (ILs), which are being synthesized as environmentally friendly alternatives to volatile organic solvents. Volatile organic solvents contribute to atmospheric pollution and ozone depletion, whereas ILs are non-volatile and less harmful to the atmosphere. Although ILs would contribute significantly less to air pollution, little is known about their potential effects on aquatic ecosystems. In 72-hour toxicity tests, we determined the acute effects of three imidazolium-based ILs (1-butyl-3-methylimidazolium bromide (bmimBr), 1-hexyl-3-methylimidazolium bromide (hmimBr), and 1-octyl-3-methylimidazolium bromide (omimBr)) on the survival of zebra mussels. As alkyl chain length decreased, median lethal concentration (LC50) decreased from 1291 mg L-1 for bmimBr, to 105 mg L-1 for hmimBr, and 21.2 mg L-1 for omimBr. For bivalve mussels, the toxicities of these ILs are comparable to the toxicities of commonly used industrial solvents (e.g., toluene, benzene). This study presents a foundation for using zebra mussels in toxicity studies as well as possible models for less common Unionid mussels.

  9. Transcriptional response of stress genes to metal exposure in zebra mussel larvae and adults

    International Nuclear Information System (INIS)

    Navarro, Anna; Faria, Melissa; Barata, Carlos; Pina, Benjamin

    2011-01-01

    Development of stress markers for the invader freshwater zebra mussel (Dreissena polymorpha) is of great interest for both conservation and biomonitoring purposes. Gene expression profiles of several putative or already established gene expression stress markers (Metallothionein, Superoxide dismutase, Catalase, Glutathione S transferase, Glutathione peroxidase, Cytochrome c oxidase, the multixenobiotic resistance P-gp1, and heat shock proteins HSP70 and HSP90) were analyzed by quantitative Real-Time PCR in adults and pediveliger larvae after exposure to metals (Hg, Cu, Cd). A defined pattern of coordinated responses to metal exposure and, presumably, to oxidative stress was observed in gills and digestive gland from adults. A similar, albeit partial response was observed in larvae, indicating an early development of stress-related gene responses in zebra mussel. The tools developed in this study may be useful both for future control strategies and for the use of zebra mussel as sentinel species in water courses with stable populations. - Coordinated expression of stress genes in zebra mussel.

  10. Transcriptional response of stress genes to metal exposure in zebra mussel larvae and adults

    Energy Technology Data Exchange (ETDEWEB)

    Navarro, Anna; Faria, Melissa; Barata, Carlos [Institute of Environmental Assessment and Water Research (IDAEA-CSIC), Jordi Girona 18, 08034 Barcelona (Spain); Pina, Benjamin, E-mail: bpcbmc@cid.csic.e [Institute of Environmental Assessment and Water Research (IDAEA-CSIC), Jordi Girona 18, 08034 Barcelona (Spain)

    2011-01-15

    Development of stress markers for the invader freshwater zebra mussel (Dreissena polymorpha) is of great interest for both conservation and biomonitoring purposes. Gene expression profiles of several putative or already established gene expression stress markers (Metallothionein, Superoxide dismutase, Catalase, Glutathione S transferase, Glutathione peroxidase, Cytochrome c oxidase, the multixenobiotic resistance P-gp1, and heat shock proteins HSP70 and HSP90) were analyzed by quantitative Real-Time PCR in adults and pediveliger larvae after exposure to metals (Hg, Cu, Cd). A defined pattern of coordinated responses to metal exposure and, presumably, to oxidative stress was observed in gills and digestive gland from adults. A similar, albeit partial response was observed in larvae, indicating an early development of stress-related gene responses in zebra mussel. The tools developed in this study may be useful both for future control strategies and for the use of zebra mussel as sentinel species in water courses with stable populations. - Coordinated expression of stress genes in zebra mussel.

  11. Zebra Mussel Research Technical Notes. Section 1 - Environmental Testing

    National Research Council Canada - National Science Library

    1998-01-01

    ...: Biology, Ecology, and Recommended Control Strategies, Larval Monitoring in a Chlorine Treatment Program to Prevent Zebra Mussel Settlement in Hydropower Facilities, Louisville District Initiates...

  12. Zebra mussel adhesion: structure of the byssal adhesive apparatus in the freshwater mussel, Dreissena polymorpha.

    Science.gov (United States)

    Farsad, Nikrooz; Sone, Eli D

    2012-03-01

    The freshwater zebra mussel (Dreissena polymorpha) owes a large part of its success as an invasive species to its ability to attach to a wide variety of substrates. As in marine mussels, this attachment is achieved by a proteinaceous byssus, a series of threads joined at a stem that connect the mussel to adhesive plaques secreted onto the substrate. Although the zebra mussel byssus is superficially similar to marine mussels, significant structural and compositional differences suggest that further investigation of the adhesion mechanisms in this freshwater species is warranted. Here we present an ultrastructural examination of the zebra mussel byssus, with emphasis on interfaces that are critical to its adhesive function. By examining the attached plaques, we show that adhesion is mediated by a uniform electron dense layer on the underside of the plaque. This layer is only 10-20 nm thick and makes direct and continuous contact with the substrate. The plaque itself is fibrous, and curiously can exhibit either a dense or porous morphology. In zebra mussels, a graded interface between the animal and the substrate mussels is achieved by interdigitation of uniform threads with the stem, in contrast to marine mussels, where the threads themselves are non-uniform. Our observations of several novel aspects of zebra mussel byssal ultrastructure may have important implications not only for preventing biofouling by the zebra mussel, but for the development of new bioadhesives as well. Copyright © 2012 Elsevier Inc. All rights reserved.

  13. Urinary androgen concentrations and social status in two species of free ranging zebra (Equus burchelli and E. grevyi).

    Science.gov (United States)

    Chaudhuri, M; Ginsberg, J R

    1990-01-01

    In both species of zebra, breeding males had higher urinary androgen concentrations (ng androgens/mg Cr) than did non-breeding bachelor males (30.0 +/- 5.0 (N = 9) versus 11.4 +/- 2.8, (N = 7) in the plains zebra; 19.0 +/- 2.2 (N = 17) versus 10.7 +/- 1.2 (N = 14) in the Grevy's zebra). In the more stable family structure of the plains zebra (single male non-territorial groups) variations in androgen concentrations could not be ascribed to any measured variable. In the Grevy's zebra, androgen values were significantly lower in samples taken from territorial (breeding) males which had temporarily abandoned their territories (N = 4) and the urinary androgen concentration for a male on his territory was negatively correlated with the time since females last visited the territory.

  14. Trophic interference by Salmo trutta on Aplochiton zebra and Aplochiton taeniatus in southern Patagonian lakes.

    Science.gov (United States)

    Elgueta, A; González, J; Ruzzante, D E; Walde, S J; Habit, E

    2013-02-01

    The length and mass ratio, diet and isotopic composition of Aplochiton zebra and Aplochiton taeniatus inhabiting a Salmo trutta-invaded and a S. trutta-free lake in southern Patagonia were compared. Results indicate that S. trutta exercises important trophic interference over A. zebra and A. taeniatus, causing changes in their dietary composition by reducing the consumption of winged Diptera through changes in feeding behaviours that involve jumping out of the water. This effect is significantly higher in A. zebra than in A. taeniatus a species that has a highly specialized diet. The dietary changes of A. zebra and A. taeniatus in sympatry with S. trutta lead to an impoverishment of their isotopic nitrogen signals (δ(15)N), suggesting a reduction of their trophic position. In the case of A. zebra, this translates into a significant decrease in its body condition factor. Such interference could lead to a population decline of this species and would explain the current distribution range decline and allopatry with S. trutta in fluvial systems. © 2012 The Authors. Journal of Fish Biology © 2012 The Fisheries Society of the British Isles.

  15. Standing sedation in captive zebra (Equus grevyi and Equus burchellii).

    Science.gov (United States)

    Hoyer, Mark; de Jong, Sara; Verstappen, Frank; Wolters, Marno

    2012-03-01

    Nine Grevy's zebras (Equus grevyi) and three Burchell's zebras (Equus burchellii) were immobilized in a standing position a total of 70 times for minor, nonpainful procedures over a 9-yr period. Standing sedation was successfully obtained with a combination of detomidine and butorphanol on 47 occasions (67.1%). Detomidine i.m. (median 0.10 mg/kg; range: 0.07-0.21) was administered by dart, followed 10 min later by butorphanol i.m. (median 0.13 mg/kg; range 0.04-0.24). The dosages were varied depending on the initial demeanor of the animal. On 23 occasions (32.9%), small amounts of etorphine (median 2.5 microg/kg; range 1.1-12.3 microg/kg) plus acepromazine (median 10 microg/kg; range 4.4-50 microg/kg) (as in Large Animal-Immobilon) had to be administered i.m. to gain sufficient sedation. In these latter cases, the animals were either excited or known for their aggressive character. The zebras were sufficiently immobilized for the length of most procedures (<45 min) without supplementation. At the end of the procedure, the animals were given atipamezole (2 mg per 1 mg detomidine used) and naltrexone (0.1 mg/kg) to reverse the sedative effects, irrespective of whether etorphine was used or not. Standing sedation, using the combination of the alpha-2 agonist detomidine and the partial agonist-antagonist opioid butorphanol (in some cases supplemented with etorphine + acepromazine), proved to be a very efficacious and safe method to be used in zebras under zoo conditions for short-lasting, nonpainful procedures.

  16. Review of techniques to prevent introduction of zebra mussels (Dreissena polymorpha) during native mussel (Unionoidea) conservation activities

    Science.gov (United States)

    Cope, W.G.; Newton, T.J.; Gatenby, C.M.

    2003-01-01

    Because of the declines in diversity and abundance of native freshwater mussels (superfamily Unionoidea), and the potential decimation of populations of native mussels resulting from the rapid spread of the exotic zebra mussel Dreissena polymorpha, management options to eliminate or reduce the threat of the zebra mussel are needed. Relocating native mussels to refugia (artificial and natural) has been proposed to mitigate the threat of zebra mussels to native species. Relocation of native mussels to refugia such as fish hatchery facilities or natural habitats within their historic range. Which are unlikely to be infested by zebra mussels, necessitates that protocols be developed to prevent the inadvertent introduction of zebra mussels. Several recent studies have developed Such protocols, and have assessed their effectiveness on the health and survival of native mussels during subsequent relocation to various refugia. The purpose of this project is to synthesize and evaluate the current protocols and to develop a set of procedures that resource managers and researchers should consider before conducting conservation activities in zebra mussel infested waters. We found that the existing protocols have many common points of concern, such as facility modification and suitability, zebra mussel risk assessment and management procedures, and health and disease management procedures. These conservation protocols may have broad applicability to other situations and locations. A summary and evaluation of the information in these main areas, along with recommended guidelines, are presented in this article.

  17. The effects of natural biofilms on the reattachment of young adult zebra mussels to artificial substrata.

    Science.gov (United States)

    Kavouras, Jerry H; Maki, James S

    2003-08-01

    This laboratory study examined the effects of natural biofilms on the reattachment of young adult zebra mussels, Dreissena polymorpha, in Petri dishes. Natural biofilms were developed in glass and polystyrene Petri dishes using water samples collected at various times of the year. Biofilms were developed over 1, 3, 8, and 14 d. Controls were clean glass and polystyrene Petri dishes. Zebra mussels collected from the field (Zebra mussels reattached to the dish surface or the shells of other mussels in the dish, or remained unattached. The data indicate that reattachment to clean glass was greater than to clean polystyrene (p Zebra mussels in control and filmed glass dishes reattached in higher percentages to the dish surface compared to the shells of other mussels (p mussel of reattachment between the dish surface and the shells of other mussels in most control polystyrene dishes (p > 0.05, ANOVA), whereas in filmed polystyrene the percentage of reattachment to the dish surface was greater than to the shells of other mussels (p zebra mussels.

  18. Evolutionary movement of centromeres in horse, donkey, and zebra.

    Science.gov (United States)

    Carbone, Lucia; Nergadze, Solomon G; Magnani, Elisa; Misceo, Doriana; Francesca Cardone, Maria; Roberto, Roberta; Bertoni, Livia; Attolini, Carmen; Francesca Piras, Maria; de Jong, Pieter; Raudsepp, Terje; Chowdhary, Bhanu P; Guérin, Gérard; Archidiacono, Nicoletta; Rocchi, Mariano; Giulotto, Elena

    2006-06-01

    Centromere repositioning (CR) is a recently discovered biological phenomenon consisting of the emergence of a new centromere along a chromosome and the inactivation of the old one. After a CR, the primary constriction and the centromeric function are localized in a new position while the order of physical markers on the chromosome remains unchanged. These events profoundly affect chromosomal architecture. Since horses, asses, and zebras, whose evolutionary divergence is relatively recent, show remarkable morphological similarity and capacity to interbreed despite their chromosomes differing considerably, we investigated the role of CR in the karyotype evolution of the genus Equus. Using appropriate panels of BAC clones in FISH experiments, we compared the centromere position and marker order arrangement among orthologous chromosomes of Burchelli's zebra (Equus burchelli), donkey (Equus asinus), and horse (Equus caballus). Surprisingly, at least eight CRs took place during the evolution of this genus. Even more surprisingly, five cases of CR have occurred in the donkey after its divergence from zebra, that is, in a very short evolutionary time (approximately 1 million years). These findings suggest that in some species the CR phenomenon could have played an important role in karyotype shaping, with potential consequences on population dynamics and speciation.

  19. Pre- and postnatal growth phenomena of Burchell's Zebra Equus Burchelli Antiquorum

    Directory of Open Access Journals (Sweden)

    G.L. Smuts

    1975-07-01

    Full Text Available Between 1969 and 1972 growth data were collected from 175 zebra Equus burchelli antiquorum and 138 zebra embryos and foetuses from the Central District of the Kruger National Park, Republic of South Africa. Statistical analysis of data indicated no significant difference between body mass of adult stallions (range == 267,3 to 373,3 kg; mean = 318,5 kg; n = 57 and adult non-pregnant mares (range = 272,6 to 386,9 kg; mean = 321,6 kg; n = 51 (t = 0,587. The heaviest zebra had a body mass of 429,4 kilogram. This was a pregnant mare carrying a 35,2 kg foetus. Von Bertalanffy growth curves indicated that shoulder heights in young zebra may reach the adult range by one year of age, the adult body mass range is, however, only attained after three years of age. These curves also showed that age classification of free roaming zebra is only reliable up to the age of about two years, after which individual variation is too great. Stallions were significantly taller at the shoulder than mares (mean = 1,8 cm (t = 2,032 and neck thickness was the only body dimension showing visible sexual dimorphism in adults. Here the stallion had a neck girth on average 8,1 cm greater than the mare. Regression equations for estimating body mass from body dimensions were calculated by using a standard logarithmic transformation and fitting a linear regression by the method of least squares and also by undertaking standard straight line linear regression analyses. Exponential curves obtained by the first method indicated that growth was not isometric (not linear and that the ratios of any of the dimensions of length to body mass were con- stantly changing, i.e. growth is allometric. Marked allometric growth differences existed between the two sexes except in the case of the heart girth-body mass relationship. Comparison of growth data from E. b. antiquorum with that of E. b. boehmi from Tanzania (Sachs 1967, indicates that E. b. antiquorum is considerably larger. Body masses

  20. Evidence for an edge effect on avian nest predation in fragmented afromontane forests in the Bamenda-Banso Highlands, NW Cameroon

    Czech Academy of Sciences Publication Activity Database

    Sedláček, O.; Mikeš, M.; Albrecht, Tomáš; Reif, J.; Hořák, D.

    2014-01-01

    Roč. 7, č. 4 (2014), s. 720-732 ISSN 1940-0829 R&D Projects: GA ČR(CZ) GAP505/11/1617 Institutional support: RVO:68081766 Keywords : Artificial nest s * Zebra finch eggs * Montane forest * Endemic species * Cameroon Mountains Subject RIV: EG - Zoology Impact factor: 1.125, year: 2014 http://tropicalconservationscience.mongabay.com/content/v7/TCS-2014-Vol7(4)_720-732_%20Ondrej.pdf

  1. Increase deposition of organic matter, polychlorinated biphenyls, and cadmium by zebra mussels (Dreissena polymorpha) in western Lake Erie

    Energy Technology Data Exchange (ETDEWEB)

    Dobson, E. P; Mackie, G. L. [Guelph Univ., Dept. of Zoology, ON (Canada)

    1998-05-01

    Biodeposition of polychlorinated biphenyls (PCBs)and cadmium by zebra mussels in the western basin of Lake Erie was investigated using sediment traps, and compared to natural rates of sedimentation. On a per unit area of organic matter, deposition rates by zebra mussels up to eight to ten times higher than natural rates of sedimentation were found. These results suggest that zebra mussels are altering contaminant movement in western Lake Erie. At the same time, it was also suggested that the net effect of biodeposition may not be as great as shown in this study since only the effects of zebra mussels on the flux of the contaminants was examined and the re-suspension factor was not considered. It was recommended that to better understand the overall effects of zebra mussels on contaminant dynamics in aquatic environments, future studies should incorporate the re-suspension factors. 27 refs., 8 tabs., 3 figs.

  2. Neural expression and post-transcriptional dosage compensation of the steroid metabolic enzyme 17β-HSD type 4

    Directory of Open Access Journals (Sweden)

    Wise Petra M

    2010-04-01

    Full Text Available Abstract Background Steroids affect many tissues, including the brain. In the zebra finch, the estrogenic steroid estradiol (E2 is especially effective at promoting growth of the neural circuit specialized for song. In this species, only the males sing and they have a much larger and more interconnected song circuit than females. Thus, it was surprising that the gene for 17β-hydroxysteroid dehydrogenase type 4 (HSD17B4, an enzyme that converts E2 to a less potent estrogen, had been mapped to the Z sex chromosome. As a consequence, it was likely that HSD17B4 was differentially expressed in males (ZZ and females (ZW because dosage compensation of Z chromosome genes is incomplete in birds. If a higher abundance of HSD17B4 mRNA in males than females was translated into functional enzyme in the brain, then contrary to expectation, males could produce less E2 in their brains than females. Results Here, we used molecular and biochemical techniques to confirm the HSD17B4 Z chromosome location in the zebra finch and to determine that HSD17B4 mRNA and activity were detectable in the early developing and adult brain. As expected, HSD17B4 mRNA expression levels were higher in males compared to females. This provides further evidence of the incomplete Z chromosome inactivation mechanisms in birds. We detected HSD17B4 mRNA in regions that suggested a role for this enzyme in the early organization and adult function of song nuclei. We did not, however, detect significant sex differences in HSD17B4 activity levels in the adult brain. Conclusions Our results demonstrate that the HSD17B4 gene is expressed and active in the zebra finch brain as an E2 metabolizing enzyme, but that dosage compensation of this Z-linked gene may occur via post-transcriptional mechanisms.

  3. Lessons learned in over 100 zebra mussel control applications at industrial facilities

    Energy Technology Data Exchange (ETDEWEB)

    McGough, C.M.; Gilland, P.H.; Muia, R.A. [Calgon Corp., Pittsburgh, PA (United States)

    1998-12-31

    Since their introduction into US waterways, Zebra Mussels (Dreissena polymorphae) have spread rapidly throughout the Great Lakes and Mississippi regions. These mussels have continued to colonize the intake pipes of industrial water supplies and water distribution systems throughout the affected areas. Their colonization has compromised plant safety and production efficiency, and steadily increased costs to water users. The design of each industrial plant water distribution system is unique. A comprehensive zebra mussel control strategy using the best available options must be considered in each specific situation. This paper discusses the successful use of one strategy (a quaternary ammonia-based molluscicide) in the battle against zebra mussels. The commercial life cycle of an industrial molluscicide began with initial toxicity screening in the laboratory. The evaluation continued at plant sites through field trials and applications. Lessons learned from these experiences helped direct the efforts toward the development of a second generation program.

  4. FindZebra: A search engine for rare diseases

    DEFF Research Database (Denmark)

    Dragusin, Radu; Petcu, Paula; Lioma, Christina Amalia

    2013-01-01

    Background: The web has become a primary information resource about illnesses and treatments for both medical and non-medical users. Standard web search is by far the most common interface for such information. It is therefore of interest to find out how well web search engines work for diagnostic...... approach for web search engines for rare disease diagnosis which includes 56 real life diagnostic cases, state-of-the-art evaluation measures, and curated information resources. In addition, we introduce FindZebra, a specialized (vertical) rare disease search engine. FindZebra is powered by open source...... medical concepts to demonstrate different ways of displaying the retrieved results to medical experts. Conclusions: Our results indicate that a specialized search engine can improve the diagnostic quality without compromising the ease of use of the currently widely popular web search engines. The proposed...

  5. A possible interpretation of the zebra pattern in solar radiation

    International Nuclear Information System (INIS)

    Fomichev, V. V.; Fainshtein, S. M.; Chernov, G. P.

    2009-01-01

    The nature of the zebra pattern in continual type-IV solar radio bursts is discussed. It is shown that, when a weakly relativistic monoenergetic proton beam propagates in a highly nonisothermal plasma, the energy of the slow beam mode can be negative and explosive instability can develop due to the interaction of the slow and fast beam modes with ion sound. Due to weak spatial dispersion, ion sound generation is accompanied by cascade merging, which leads to stabilization of explosive instability. The zebra pattern forms due to the scattering of fast protons by ion sound harmonics. The efficiency of the new mechanism is compared with that of previously discussed mechanisms.

  6. Application experience with ADBAC/DGH cationic surfactants for zebra mussel control in a nuclear service water system

    International Nuclear Information System (INIS)

    Jung, W.R.; Lacy, J.R.; Post, R.

    1992-01-01

    In response to the introduction and rapid growth of the zebra mussel population in the Great Lakes and the issuance of NRC Generic Letter 89-13 (Service Water Problems Affecting Safety-Related Equipment). A midwest nuclear station instituted a zebra mussel monitoring and control program. The nuclear station uses Lake Michigan as a cooling water source for two 1,100 MW Westinghouse 4-loop design, pressurized water reactors (PWR). Two years of monitoring indicated a growth in zebra mussel population from 0.5 organisms/m 2 in July 1990 to 100 organisms/m 2 by November 1990. This rapid increase indicated an urgent need for viable methods of zebra mussel control to protect the plant's essential service water (ESW) and non-essential service water (NESW) systems. In April 1991, the station formulated a plan that combined increased system inlet temperature with targeted application of a proprietary product containing two cationic surfactants, ADBAC/DGH. Sidestream biomonitoring boxes were seeded with zebra mussels and observed as a measure of the efficacy of the treatment. Where recommended dosages and duration were maintained, 100% control was achieved

  7. In-situ measurements of ice nucleating particles with FINCH (Fast Ice Nucleus Chamber)

    Science.gov (United States)

    Kohl, Rebecca; Frank, Fabian; Curtius, Joachim; Rose, Diana

    2017-04-01

    Ice nucleating particles (INPs), which are a small fraction of the total aerosol population, are capable of triggering ice formation under atmospheric conditions. Since INPs play an important role for the radiative properties of clouds as well as for the formation of precipitation it is important to get quantitative information on the ice activity of various atmospheric aerosol species. With the Fast Ice Nucleus Chamber (FINCH; Bundke et al., 2008) the number concentration of INP is determined at different freezing temperatures and supersaturations. In contrast to other commonly used INP counters, i.e., continuous flow diffusion chambers (CFDCs, DeMott et al., 2011), in FINCH the supersaturation is reached by mixing the sample flow of ambient aerosol with a warm moist as well as a cold dry airflow. By changing the flow rates and temperatures of the individual airflows the freezing temperature (down to -50°C) and supersaturation (up to above water saturation) can be varied relatively quickly. Particles that are ice active at the prescribed freezing temperature and supersaturation grow to crystals and are counted by a home-built optical particle counter (OPC) mounted below the chamber (Bundke et al., 2010). FINCH was operated during the four-week INUIT-BACCHUS-ACTRIS field campaign in Cyprus in April 2016. The measuring site was the location of the Cyprus Atmospheric Observatory (CAO) at Agia Marina Xyliatou, which is typically influenced by dust from the Sahara and the Middle East, an aerosol that is known to have relatively good ice nucleating ability. First results from this campaign will be presented. Acknowledgements: The authors thank the entire INUIT-BACCHUS-ACTRIS campaign team for their cooperation and support. The INUIT-2 project is financed by the German Research Foundation DFG (FOR 1525). The INUIT-Cyprus campaign is a cooperation with the EU-funded project BACCHUS and is also funded by ACTRIS-TNA. References: Bundke, U., Nillius, B., Jaenicke, R

  8. Proximate and fatty acid composition of zebra (Equus quagga burchellii) muscle and subcutaneous fat.

    Science.gov (United States)

    Hoffman, Louwrens C; Geldenhuys, Greta; Cawthorn, Donna-Mareè

    2016-08-01

    The meat from African game species is healthy, naturally produced and increasingly popular with consumers. Among these species, zebra (Equus quagga burchellii) are growing in number in South Africa, with the meat from surplus animals holding potential to contribute to food security and economic stability. Despite being consumed locally and globally, little information exists on the composition of zebra meat. This study aimed to determine the proximate composition of zebra meat as well as the fatty acid composition of the intramuscular (IMF) and subcutaneous (SCF) fat. Zebra longissimus lumborum muscle was shown to have a high mean protein content (22.29 g per 100 g) and low mean fat content (1.47 g per 100 g). High proportions of polyunsaturated fatty acids (PUFAs) were found in the IMF (41.15%) and SCF (37.71%), mainly comprising α-linolenic (C18:3n-3) and linoleic (C18:2n-6) acids. Furthermore, the IMF and SCF had favourable PUFA/saturated fatty acid ratios (>0.4) and omega-6/omega-3 ratios (<4), indicating that both components are healthy lipid food sources. This study has shed new light on the nutritional value of zebra meat, which will not only be important for food product labelling, nutritional education and incorporation into food composition databases, but will also be indispensable for marketing and export purposes. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  9. Low diversity, activity, and density of transposable elements in five avian genomes.

    Science.gov (United States)

    Gao, Bo; Wang, Saisai; Wang, Yali; Shen, Dan; Xue, Songlei; Chen, Cai; Cui, Hengmi; Song, Chengyi

    2017-07-01

    In this study, we conducted the activity, diversity, and density analysis of transposable elements (TEs) across five avian genomes (budgerigar, chicken, turkey, medium ground finch, and zebra finch) to explore the potential reason of small genome sizes of birds. We found that these avian genomes exhibited low density of TEs by about 10% of genome coverages and low diversity of TEs with the TE landscapes dominated by CR1 and ERV elements, and contrasting proliferation dynamics both between TE types and between species were observed across the five avian genomes. Phylogenetic analysis revealed that CR1 clade was more diverse in the family structure compared with R2 clade in birds; avian ERVs were classified into four clades (alpha, beta, gamma, and ERV-L) and belonged to three classes of ERV with an uneven distributed in these lineages. The activities of DNA and SINE TEs were very low in the evolution history of avian genomes; most LINEs and LTRs were ancient copies with a substantial decrease of activity in recent, with only LTRs and LINEs in chicken and zebra finch exhibiting weak activity in very recent, and very few TEs were intact; however, the recent activity may be underestimated due to the sequencing/assembly technologies in some species. Overall, this study demonstrates low diversity, activity, and density of TEs in the five avian species; highlights the differences of TEs in these lineages; and suggests that the current and recent activity of TEs in avian genomes is very limited, which may be one of the reasons of small genome sizes in birds.

  10. A dominance shift from the zebra mussel to the invasive quagga mussel may alter the trophic transfer of metals

    International Nuclear Information System (INIS)

    Matthews, Jonathan; Schipper, Aafke M.; Hendriks, A. Jan; Yen Le, T.T.; Vaate, Abraham bij de; Velde, Gerard van der; Leuven, Rob S.E.W.

    2015-01-01

    Bioinvasions are a major cause of biodiversity and ecosystem changes. The rapid range expansion of the invasive quagga mussel (Dreissena rostriformis bugensis) causing a dominance shift from zebra mussels (Dreissena polymorpha) to quagga mussels, may alter the risk of secondary poisoning to predators. Mussel samples were collected from various water bodies in the Netherlands, divided into size classes, and analysed for metal concentrations. Concentrations of nickel and copper in quagga mussels were significantly lower than in zebra mussels overall. In lakes, quagga mussels contained significantly higher concentrations of aluminium, iron and lead yet significantly lower concentrations of zinc66, cadmium111, copper, nickel, cobalt and molybdenum than zebra mussels. In the river water type quagga mussel soft tissues contained significantly lower concentrations of zinc66. Our results suggest that a dominance shift from zebra to quagga mussels may reduce metal exposure of predator species. - Highlights: • Invading quagga mussels often displace existing zebra mussels. • Interspecies difference in metal concentration may alter exposure of predators. • Zebra and quagga mussel soft tissue were analysed for metal concentrations. • Generally, quagga mussels contained lower concentrations of metals. • A dominance shift to quagga mussels may reduce metal exposure of predators. - A shift in dominance from zebra mussels to invading quagga mussels may reduce the transfer of metals to predator species

  11. Putative clinical piroplasmosis in a Burchell's zebra (Equus quagga burchelli : clinical communication

    Directory of Open Access Journals (Sweden)

    F. Lampen

    2009-05-01

    Full Text Available A 10-year-old tame zebra gelding was presented after suffering from lethargy, nervousness, reported anaemia and icterus as well as a decreased appetite. These symptoms were seen over some months, with changing severity. The animal was immobilised, treated, and blood specimens were submitted for haematology and biochemistry. This report describes molecular characterisation of Theileria equi recovered from this animal, as well as the clinical findings, treatment and historical relevance of piroplasmosis in zebra in southern Africa.

  12. Are Horses Like Zebras, or Vice Versa? Children's Sensitivity to the Asymmetries of Directional Comparisons

    Science.gov (United States)

    Chestnut, Eleanor K.; Markman, Ellen M.

    2016-01-01

    Adults exhibit strong preferences when framing symmetrical relations. Adults prefer, for example, "A zebra is like a horse" to "A horse is like a zebra," and "The bicycle is near the building" to "The building is near the bicycle." This is because directional syntax requires more typical or prominent items…

  13. Scope of problem assessed at IVO. The zebra mussel`s campaign of world conquest

    Energy Technology Data Exchange (ETDEWEB)

    Silvonen, J; Oesch, P [ed.

    1998-07-01

    The migrating shell - or `zebra mussel` as it is called on account of its black and white stripes - was originally a fresh-water mussel, but has since also adapted to brackish waters. As a result of human activity the species has spread quickly and widely from its native habitat. Operators of power plants and water treatment plants in particular have not been very happy about this. During its larval stage the zebra mussel can enter the cooling water systems; fasten itself to the pipes and - in the worst case - clog the system. The Environmental Protection Division of IVO has been assessing the spread of the zebra mussel and the resulting problems with the aid of reference literature and the assistance of Finnish researchers

  14. Summary of Ontario Hydro's 1990-91 zebra mussel research program

    International Nuclear Information System (INIS)

    Claudi, R.; Wiancko, P.M.

    1992-01-01

    Ontario Hydro is the principal supplier of electricity to the Province of Ontario. It serves 3.6 million customers, with an inservice capacity of 28,200 MW. Ontario Hydro has seven fossil, five nuclear, and four hydraulic stations in the Great Lakes Basin and surrounding watershed. In addition, there are another 60 inland hydraulic stations and numerous dams. As the largest single user of raw water from the Great Lakes Basin, Ontario Hydro recognized the need to control zebra mussels early in 1989. At that time, very little was known in North America about the zebra mussel life cycle and potential impact. European utilities were consulted, but as we now know, zebra mussels are not perceived to be a problem in Europe at this time. To satisfy the immediate need for control, chlorination was identified as the most effective interim measure to prevent the fouling of systems which draw water from the aquatic environment. Due to the current regulatory environment, this solution is considered short term and Ontario Hydro was compelled to initiate a comprehensive research effort aimed at providing alternative methods of control. Most of the research effort during 1990, was methods of control. Most of the research effort during 1990, was directed towards this goal. Many alternative control measures, both chemical and nonchemical were considered. Also considered were the potential effects of the control measures and zebra mussels on station operations. A multidisciplinary team involving aquatic biologists, chemists, corrosion specialists, and civil and mechanical engineers from the various departments of Ontario Hydro was asked to address the problem. Some of the research also involved collaborative studies with universities, US utilities, American Water Works Association, and Canadian industries. Following is a summary of the research effort in 1990, and a preview of the research underway in 1991

  15. Grazing on colonial and filamentous, toxic and non-toxic cyanobacteria by the zebra mussel Dreissena polymorpha

    NARCIS (Netherlands)

    Pires, L.M.D.; Bontes, B.M.; Van Donk, E.; Ibelings, B.W.

    2005-01-01

    Colony forming and toxic cyanobacteria form a problem in surface waters of shallow lakes, both for recreation and wildlife. Zebra mussels, Dreissena polymorpha, have been employed to help to restore shallow lakes in the Netherlands, dominated by cyanobacteria, to their former clear state. Zebra

  16. Switch from sexual to parthenogenetic reproduction in a zebra shark.

    Science.gov (United States)

    Dudgeon, Christine L; Coulton, Laura; Bone, Ren; Ovenden, Jennifer R; Thomas, Severine

    2017-01-16

    Parthenogenesis is a natural form of asexual reproduction in which embryos develop in the absence of fertilisation. Most commonly found in plants and invertebrate organisms, an increasing number of vertebrate species have recently been reported employing this reproductive strategy. Here we use DNA genotyping to report the first demonstration of an intra-individual switch from sexual to parthenogenetic reproduction in a shark species, the zebra shark Stegostoma fasciatum. A co-housed, sexually produced daughter zebra shark also commenced parthenogenetic reproduction at the onset of maturity without any prior mating. The demonstration of parthenogenesis in these two conspecific individuals with different sexual histories provides further support that elasmobranch fishes may flexibly adapt their reproductive strategy to environmental circumstances.

  17. A general auditory bias for handling speaker variability in speech? Evidence in humans and songbirds

    Directory of Open Access Journals (Sweden)

    Buddhamas eKriengwatana

    2015-08-01

    Full Text Available Different speakers produce the same speech sound differently, yet listeners are still able to reliably identify the speech sound. How listeners can adjust their perception to compensate for speaker differences in speech, and whether these compensatory processes are unique only to humans, is still not fully understood. In this study we compare the ability of humans and zebra finches to categorize vowels despite speaker variation in speech in order to test the hypothesis that accommodating speaker and gender differences in isolated vowels can be achieved without prior experience with speaker-related variability. Using a behavioural Go/No-go task and identical stimuli, we compared Australian English adults’ (naïve to Dutch and zebra finches’ (naïve to human speech ability to categorize /ɪ/ and /ɛ/ vowels of an novel Dutch speaker after learning to discriminate those vowels from only one other speaker. Experiment 1 and 2 presented vowels of two speakers interspersed or blocked, respectively. Results demonstrate that categorization of vowels is possible without prior exposure to speaker-related variability in speech for zebra finches, and in non-native vowel categories for humans. Therefore, this study is the first to provide evidence for what might be a species-shared auditory bias that may supersede speaker-related information during vowel categorization. It additionally provides behavioural evidence contradicting a prior hypothesis that accommodation of speaker differences is achieved via the use of formant ratios. Therefore, investigations of alternative accounts of vowel normalization that incorporate the possibility of an auditory bias for disregarding inter-speaker variability are warranted.

  18. CINCH (confocal incoherent correlation holography) super resolution fluorescence microscopy based upon FINCH (Fresnel incoherent correlation holography).

    Science.gov (United States)

    Siegel, Nisan; Storrie, Brian; Bruce, Marc; Brooker, Gary

    2015-02-07

    FINCH holographic fluorescence microscopy creates high resolution super-resolved images with enhanced depth of focus. The simple addition of a real-time Nipkow disk confocal image scanner in a conjugate plane of this incoherent holographic system is shown to reduce the depth of focus, and the combination of both techniques provides a simple way to enhance the axial resolution of FINCH in a combined method called "CINCH". An important feature of the combined system allows for the simultaneous real-time image capture of widefield and holographic images or confocal and confocal holographic images for ready comparison of each method on the exact same field of view. Additional GPU based complex deconvolution processing of the images further enhances resolution.

  19. Zebra chip development during storage: cause for concern?

    Science.gov (United States)

    Zebra chip disease is associated with infections by ‘Candidatus Liberibacter solanacearum’ (Lso), a bacterium spread by the potato psyllid Bactericera cockerelli. A major concern of the potato industry is the likelihood that Lso could cause asymptomatic infections prior to placement of tubers in col...

  20. Peregrine falcon predation of endangered Laysan teal and Laysan Finches on remote Hawaiian atolls

    Science.gov (United States)

    Reynolds, Michelle H.; Nash, Sarah A.B.; Courtot, Karen

    2015-01-01

    We report the first records of Peregrine falcon (Falco peregrinus) predation on endangered Laysan teal (or duck; Anas laysanensis) and predation on endangered Laysan finches (Telespiza cantans). At Midway Atoll, vagrant Peregrine falcons killed ≥4% of a newly translocated Laysan teal population in 2006 and ≥2% in 2008. On Laysan Island during 2008–2009, remains of >76 Laysan finches (<1% of the population) were found at peregrine perches. On Midway Atoll, all depredated Laysan teal and other seabirds were recovered at kill sites on tarmac (runways). If the frequency or duration of vagrant raptors visitation increases at small atolls, this could pose a mortality risk to consider, especially during proposed translocations of endangered species. Vegetation restoration of abandoned runways near wetlands at Midway Atoll would provide cover and may help reduce mortality of endangered species due to vagrant raptors.

  1. Metal contamination in zebra mussels (Dreissena polymorpha) along the St. Lawrence River.

    Science.gov (United States)

    Kwan, K H Michael; Chan, Hing Man; de Lafontaine, Yves

    2003-01-01

    In order to evaluate the use of zebra mussels as biomonitors for metal bioavailability in the St. Lawrence River, we tested the hypothesis that the concentrations of 11 metals in zebra mussels vary significantly between sites along the river and that the season of collection and body size affect metal bioaccumulation. Mussels were collected at 14 sites during June 1996 and at monthly intervals at one site. Specimens were grouped in three size classes and their soft tissue was analyzed for As, Ca, Cd, Cr, Hg, Mn, Ni, Pb, Se, and Zn. Significant size effects were found for Ca, Cd, Cr, Cu, Ni and Zn. Spatial and seasonal variations in bioconcentration were significant for all metals. Spatial patterns in contamination that corresponded to known point sources of pollution or hydrology of the river were identified by principal component analysis. Seasonal variations can be attributed to the reproductive cycle of mussels and hydrological variability of the river. In comparison with values reported for zebra mussels in other contaminated sites in North America and Europe, levels of metal in the St. Lawrence River are low or intermediate. Our results show that when controlled for size and seasonal effects, zebra mussels represent a useful biomonitor for metal availability in the river and may offer an interesting alternative to native mussels and fish for such a role. Local contamination by some toxic metals is still a cause for concern in the St. Lawrence River.

  2. Mortality of zebra mussel, Dreissena polymorpha, veligers during downstream transport

    Science.gov (United States)

    Horvath, T.G.; Lamberti, G.A.

    1999-01-01

    1. Streams flowing from lakes which contain zebra mussels, Dreissena polymorpha, provide apparently suitable habitats for mussel colonization and downstream range expansion, yet most such streams contain few adult mussels. We postulated that mussel veligers experience high mortality during dispersal via downstream transport. They tested this hypothesis in Christiana Creek, a lake-outlet stream in south-western Michigan, U.S.A., in which adult mussel density declined exponentially with distance downstream. 2. A staining technique using neutral red was developed and tested to distinguish quickly live and dead veligers. Live and dead veligers were distinguishable after an exposure of fresh samples to 13.3 mg L-1 of neutral red for 3 h. 3. Neutral red was used to determine the proportion of live veligers in samples taken longitudinally along Christiana Creek. The proportion of live veligers (mean ?? SE) declined from 90 ?? 3% at the lake outlet to 40 ?? 8% 18 km downstream. 4. Veligers appear to be highly susceptible to damage by physical forces (e.g. shear), and therefore, mortality in turbulent streams could be an important mechanism limiting zebra mussel dispersal to downstream reaches. Predictions of zebra mussel spread and population growth should consider lake-stream linkages and high mortality in running waters.

  3. Bioassessment of mercury, cadmium, polychlorinated biphenyls, and pesticides in the Upper Mississippi River with zebra mussels (Dreissena polymorpha)

    Energy Technology Data Exchange (ETDEWEB)

    Cope, W.G.; Bartsch, M.R.; Rada, R.G.; Balogh, S.J.; Rupprecht, J.E.; Young, R.D.; Johnson, D.K.

    1999-12-15

    Zebra mussels (Dreissena polymorpha) were sampled from artificial substrates deployed from May 30 to October 19, 1995, at 19 locks and dams from Minneapolis, MN, to Muscatine, IA. Analyses of composite tissue samples of zebra mussels revealed accumulation of mercury (Hg), cadmium (Cd), and polychlorinated biphenyls (PCBs) during a 143-d exposure period. Concentrations of total Hg ranged from 2.6 to 6.1 ng/g wet weight and methylmercury (CH{sub 3}Hg) from 1.0 to 3.3 ng/g wet weight. About 50% of the mean total Hg in zebra mussels was CH{sub 3}Hg. Cadmium ranged from 76 to 213 ng/g wet weight. Concentrations of total PCBs in zebra mussels varied longitudinally, but the composition of PCB congeners was similar throughout the river. Chlordane and dieldrin were the only two pesticides detected of the 15 analyzed. Zebra mussels are sentinels of contaminant bioavailability in the Upper Mississippi River and may be an important link in the trophic transfer of contaminants in the river because of their increasing importance in the diets of certain fish and waterfowl.

  4. Manual semen collection from a Grevy's zebra stallion (Equus grevyi), onset of sperm production, semen characteristics, and cryopreservation of semen, with a comparison to the sperm production from a Grant's Zebra stallion (Equus burchelli boehmi).

    Science.gov (United States)

    Crump, J P; Crump, J W

    1994-01-01

    A manual technique was used to collect representative ejaculates from an unrestrained Grevy's zebra stallion beginning at 13 mo of age to determine the onset of sperm production, to calculate the number of spermatozoa produced per ejaculate, and to determine any seasonality associated with sperm production. Spermatozoa first appeared in the ejaculate at 31 mo of age. By 48 mo of age the zebra was producing up to 40 billion spermatozoa per ejaculate. Progressive sperm motility ranged from 75 to 95%. Gel-free semen volume averaged 75 to 120 ml/ejaculate. Gel volume ranged from 0 to 1100 ml/ejaculate. Semen was frozen in 2 different extenders in 0.5-ml PVC straws. The post-thaw motility of cryopreserved spermatozoa ranged from 30 to 70%. A domestic horse mare became pregnant on the first cycle after insemination with frozen-thawed spermatozoa from this zebra. Sperm production data obtained from semen collections made on a Grant's Zebra stallion from 3 to 8 yr of age is presented for comparison of the 2 species.

  5. Faithful reconstruction of digital holograms captured by FINCH using a Hamming window function in the Fresnel propagation.

    Science.gov (United States)

    Siegel, Nisan; Rosen, Joseph; Brooker, Gary

    2013-10-01

    Recent advances in Fresnel incoherent correlation holography (FINCH) increase the signal-to-noise ratio in hologram recording by interference of images from two diffractive lenses with focal lengths close to the image plane. Holograms requiring short reconstruction distances are created that reconstruct poorly with existing Fresnel propagation methods. Here we show a dramatic improvement in reconstructed fluorescent images when a 2D Hamming window function substituted for the disk window typically used to bound the impulse response in the Fresnel propagation. Greatly improved image contrast and quality are shown for simulated and experimentally determined FINCH holograms using a 2D Hamming window without significant loss in lateral or axial resolution.

  6. High variation and very low differentiation in wide ranging plains zebra (Equus quagga): insights from mtDNA and microsatellites.

    Science.gov (United States)

    Lorenzen, Eline D; Arctander, Peter; Siegismund, Hans R

    2008-06-01

    Patterns of genetic differentiation in the plains zebra (Equus quagga) were analysed using mitochondrial DNA control region variation and seven microsatellites. The six morphologically defined subspecies of plains zebra lacked the population genetic structure indicative of distinct evolutionary units. Both marker sets showed high levels of genetic variation and very low levels of differentiation. There was no geographical structuring of mitochondrial DNA haplotypes in the phylogenetic tree, and the plains zebra showed the lowest overall differentiation recorded in any African ungulate studied so far. Arid-adapted African ungulates have shown significant regional genetic structuring in support of the Pleistocene refuge theory. This was not the case in the zebra, and the data are discussed in relation to the impact of Pleistocene climate change on a nonbovid member of the savannah ungulate community. The only other species showing a similar absence of genetic structuring is the African buffalo (Syncerus caffer), but this taxon lacks the high levels of morphological variation present in the plains zebra.

  7. The zebra mussel; El mejillon cebra

    Energy Technology Data Exchange (ETDEWEB)

    Bertran, A.; Esparza, J.L.; Munte, L.

    2010-07-01

    The aim of this article is, on the one hand, to provide information about the zebra mussel, its behavior, its effect on the ecosystem and the problems it poses for industry (especially in the CNA cooling systems) and, on the other hand, to review the strategies and technologies needed to control de mussel and to present the solution adopted by the power plant to combat the plague. (Author).

  8. Robotic removal of zebra mussel accumulations in a nuclear power plant screenhouse

    International Nuclear Information System (INIS)

    Kotler, S.R.; Mallen, E.C.; Tamms, K.M.

    1995-01-01

    Zebra mussel accumulations in the power plant intake system have increased over the last four years and have become a maintenance issue. Several treatment methods have been used, including mechanical cleaning by divers. This is limited to areas of relatively low flow velocity. Various sections of the screenhouse are not accessible except during an outage or when one of the intake tunnels can be otherwise be blocked and flow reduced. In addition, diver services are relatively costly. For the above reasons, the Indiana Michigan Power Co., Cook Nuclear Plant, contracted with ARD Environmental Inc. to develop and test a robotic system as an alternative to cleaning by divers. The first phase of this project addressed the requirement to clean the screenhouse floor in all areas, including those with high flow velocity. Subsequent phases will address robotic cleaning of other areas of the intake and the screenhouse structures. The objectives of the project were to: (1) Demonstrate the ability to deploy and retrieve a modified XT1000 vehicle in the inlet bay and screen bays; (2) Remove the accumulations of zebra mussels and possibly other pumpable material from the floor; (3) Reduce or eliminate the need for diver services and reduce overall cost of removing accumulations of zebra mussels; and, (4) Critique operations and develop recommendations for further enhancements to the robotic equipment and materials handling system. Implementation of the operating plan commenced on September 8, 1994, and was completed on October 7, 1994. The project demonstrated that robotic techniques are an efficient and cost effective alternative to diver operations for mechanical removal of zebra mussels. In particular, the robotic system was able to operate effectively in the high flow velocity areas including those at the intake tunnels. The ability to operate in the high flow areas means that zebra mussel removal may take place at any time, without affecting normal plant operations

  9. Stoichiometric constraints do not limit successful invaders: zebra mussels in Swedish lakes.

    Science.gov (United States)

    Naddafi, Rahmat; Eklöv, Peter; Pettersson, Kurt

    2009-01-01

    Elemental imbalances of carbon (C): nitrogen (N): phosphorus (P) ratios in food resources can constrain the growth of grazers owning to tight coupling between growth rate, RNA allocation and biomass P content in animals. Testing for stoichiometric constraints among invasive species is a novel challenge in invasion ecology to unravel how a successful invader tackles ecological barriers in novel ecosystems. We examined the C:P and N:P ratios and the condition factor of a successful invader in lakes, the zebra mussel (Dreissena polymorpha), collected from two Swedish lakes. Concurrently, we analyzed the elemental composition of the food (seston) and tissue of the mussels in which nutrient composition of food and mussels varied over time. Zebra mussel condition factor was weakly related to the their own tissue N:P and C:P ratios, although the relation with the later ratio was not significant. Smaller mussels had relatively lower tissue N:P ratio and higher condition factor. There was no difference in C:P and N:P ratios between seston and mussels' tissues. Our results indicated that the variation in nutrient stoichiometry of zebra mussels can be explained by food quality and quantity. Our study suggests that fitness of invasive zebra mussels is not constrained by nutrient stoichiometry which is likely to be important for their proliferation in novel ecosystems. The lack of imbalance in C:P and N:P ratios between seston and mussels along with high tissue C:P ratio of the mussel allow them to tolerate potential P limitation and maintain high growth rate. Moreover, zebra mussels are able to change their tissue C:P and N:P ratios in response to the variation in elemental composition of their food. This can also help them to bypass potential nutrient stoichiometric constraints. Our finding is an important step towards understanding the mechanisms contributing to the success of exotic species from stoichiometric principles.

  10. Stoichiometric constraints do not limit successful invaders: zebra mussels in Swedish lakes.

    Directory of Open Access Journals (Sweden)

    Rahmat Naddafi

    Full Text Available Elemental imbalances of carbon (C: nitrogen (N: phosphorus (P ratios in food resources can constrain the growth of grazers owning to tight coupling between growth rate, RNA allocation and biomass P content in animals. Testing for stoichiometric constraints among invasive species is a novel challenge in invasion ecology to unravel how a successful invader tackles ecological barriers in novel ecosystems.We examined the C:P and N:P ratios and the condition factor of a successful invader in lakes, the zebra mussel (Dreissena polymorpha, collected from two Swedish lakes. Concurrently, we analyzed the elemental composition of the food (seston and tissue of the mussels in which nutrient composition of food and mussels varied over time. Zebra mussel condition factor was weakly related to the their own tissue N:P and C:P ratios, although the relation with the later ratio was not significant. Smaller mussels had relatively lower tissue N:P ratio and higher condition factor. There was no difference in C:P and N:P ratios between seston and mussels' tissues. Our results indicated that the variation in nutrient stoichiometry of zebra mussels can be explained by food quality and quantity.Our study suggests that fitness of invasive zebra mussels is not constrained by nutrient stoichiometry which is likely to be important for their proliferation in novel ecosystems. The lack of imbalance in C:P and N:P ratios between seston and mussels along with high tissue C:P ratio of the mussel allow them to tolerate potential P limitation and maintain high growth rate. Moreover, zebra mussels are able to change their tissue C:P and N:P ratios in response to the variation in elemental composition of their food. This can also help them to bypass potential nutrient stoichiometric constraints. Our finding is an important step towards understanding the mechanisms contributing to the success of exotic species from stoichiometric principles.

  11. RFSP simulations of Darlington FINCH refuelling transient

    International Nuclear Information System (INIS)

    Carruthers, E.V.; Chow, H.C.

    1997-01-01

    Immediately after refuelling of a channel, the fresh bundles are free of fission products. Xenon-135, the most notable of the saturating fission products, builds up to an equilibrium level in about 30 h. The channel power of the refuelled channel would therefore initially peak and then drop to a steady-state level. The RFSP code can track saturating-fission-product transients and power transients. The Fully INstrumented CHannels (FINCHs) in Darlington NGS provides channel power data on the refuelling power transients. In this paper, such data has been used to identify the physical evidence of the fission-product transient effect on channel power, and to validate RFSP fission-product-driver calculation results. (author)

  12. Network metrics reveal differences in social organization between two fission-fusion species, Grevy's zebra and onager.

    Science.gov (United States)

    Sundaresan, Siva R; Fischhoff, Ilya R; Dushoff, Jonathan; Rubenstein, Daniel I

    2007-02-01

    For species in which group membership frequently changes, it has been a challenge to characterize variation in individual interactions and social structure. Quantifying this variation is necessary to test hypotheses about ecological determinants of social patterns and to make predictions about how group dynamics affect the development of cooperative relationships and transmission processes. Network models have recently become popular for analyzing individual contacts within a population context. We use network metrics to compare populations of Grevy's zebra (Equus grevyi) and onagers (Equus hemionus khur). These closely related equids, previously described as having the same social system, inhabit environments differing in the distribution of food, water, and predators. Grevy's zebra and onagers are one example of many sets of coarsely similar fission-fusion species and populations, observed elsewhere in other ungulates, primates, and cetaceans. Our analysis of the population association networks reveals contrasts consistent with their distinctive environments. Grevy's zebra individuals are more selective in their association choices. Grevy's zebra form stable cliques, while onager associations are more fluid. We find evidence that females associate assortatively by reproductive state in Grevy's zebra but not in onagers. The current approach demonstrates the utility of network metrics for identifying fine-grained variation among individuals and populations in association patterns. From our analysis, we can make testable predictions about behavioral mechanisms underlying social structure and its effects on transmission processes.

  13. Early life manipulations of vasopressin-family peptides alter vocal learning.

    Science.gov (United States)

    Baran, Nicole M; Peck, Samantha C; Kim, Tabitha H; Goldstein, Michael H; Adkins-Regan, Elizabeth

    2017-07-26

    Vocal learning from social partners is crucial for the successful development of communication in a wide range of species. Social interactions organize attention and enhance motivation to learn species-typical behaviour. However, the neurobiological mechanisms connecting social motivation and vocal learning are unknown. Using zebra finches ( Taeniopygia guttata ), a ubiquitous model for vocal learning, we show that manipulations of nonapeptide hormones in the vasopressin family (arginine vasotocin, AVT) early in development can promote or disrupt both song and social motivation. Young male zebra finches, like human infants, are socially gregarious and require interactive feedback from adult tutors to learn mature vocal forms. To investigate the role of social motivational mechanisms in song learning, in two studies, we injected hatchling males with AVT or Manning compound (MC, a nonapeptide receptor antagonist) on days 2-8 post-hatching and recorded song at maturity. In both studies, MC males produced a worse match to tutor song than controls. In study 2, which experimentally controlled for tutor and genetic factors, AVT males also learned song significantly better compared with controls. Furthermore, song similarity correlated with several measures of social motivation throughout development. These findings provide the first evidence that nonapeptides are critical to the development of vocal learning. © 2017 The Author(s).

  14. Melanin-based color of plumage: role of condition and of feathers' microstructure

    Science.gov (United States)

    D'Alba, Liliana; Van Hemert, Caroline R.; Spencer, Karen A.; Heidinger, Britt J.; Gill, Lisa; Evans, Neil P.; Monaghan, Pat; Handel, Colleen M.; Shawkey, Matthew D.

    2014-01-01

    Whether melanin-based colors honestly signal a bird's condition during the growth of feathers is controversial, and it is unclear if or how the physiological processes underlying melanogenesis or color-imparting structural feather microstructure may be adversely affected by condition. Here we report results from two experiments designed to measure the effect of condition on expression of eumelanic and pheomelanic coloration in black-capped chickadees (Poecile atricapillus) and zebra finches (Taeniopygia guttata), respectively. In chickadees, we compared feathers of birds affected and unaffected by avian keratin disorder, while in zebra finches we compared feathers of controls with feathers of those subjected to an unpredictable food supply during development. In both cases we found that control birds had brighter feathers (higher total reflectance) and more barbules, but similar densities of melanosomes. In addition, the microstructure of the feathers explained variation in color more strongly than did melanosome density. Together, these results suggest that melanin-based coloration may in part be condition-dependent, but that this may be driven by changes in keratin and feather development, rather than melanogenesis itself. Researchers should be cautious when assigning variation in melanin-based color to melanin alone and microstructure of the feather should be taken into account.

  15. Developmental song learning as a model to understand neural mechanisms that limit and promote the ability to learn.

    Science.gov (United States)

    London, Sarah E

    2017-11-20

    Songbirds famously learn their vocalizations. Some species can learn continuously, others seasonally, and still others just once. The zebra finch (Taeniopygia guttata) learns to sing during a single developmental "Critical Period," a restricted phase during which a specific experience has profound and permanent effects on brain function and behavioral patterns. The zebra finch can therefore provide fundamental insight into features that promote and limit the ability to acquire complex learned behaviors. For example, what properties permit the brain to come "on-line" for learning? How does experience become encoded to prevent future learning? What features define the brain in receptive compared to closed learning states? This piece will focus on epigenomic, genomic, and molecular levels of analysis that operate on the timescales of development and complex behavioral learning. Existing data will be discussed as they relate to Critical Period learning, and strategies for future studies to more directly address these questions will be considered. Birdsong learning is a powerful model for advancing knowledge of the biological intersections of maturation and experience. Lessons from its study not only have implications for understanding developmental song learning, but also broader questions of learning potential and the enduring effects of early life experience on neural systems and behavior. Copyright © 2017. Published by Elsevier B.V.

  16. Equid herpesvirus 9 (EHV-9) isolates from zebras in Ontario, Canada, 1989 to 2007.

    Science.gov (United States)

    Rebelo, Ana Rita; Carman, Susy; Shapiro, Jan; van Dreumel, Tony; Hazlett, Murray; Nagy, Éva

    2015-04-01

    The objective of this study was to identify and partially characterize 3 equid herpesviruses that were isolated postmortem from zebras in Ontario, Canada in 1989, 2002, and 2007. These 3 virus isolates were characterized by plaque morphology, restriction fragment length polymorphism (RFLP) of their genomic deoxyribonucleic acid (DNA), real-time polymerase chain reaction (PCR) assay, and sequence analyses of the full length of the glycoprotein G (gG) gene (ORF70) and a portion of the DNA polymerase gene (ORF30). The isolates were also compared to 3 reference strains of equid herpesvirus 1 (EHV-1). Using rabbit kidney cells, the plaques for the isolates from the zebras were found to be much larger in size than the EHV-1 reference strains. The RFLP patterns of the zebra viruses differed among each other and from those of the EHV-1 reference strains. Real-time PCR and sequence analysis of a portion of the DNA polymerase gene determined that the herpesvirus isolates from the zebras contained a G at nucleotide 2254 and a corresponding N at amino acid position 752, which suggested that they could be neuropathogenic EHV-1 strains. However, subsequent phylogenetic analysis of the gG gene suggested that they were EHV-9 and not EHV-1.

  17. Evolutionary constraints on equid domestication: Comparison of flight initiation distances of wild horses (Equus caballus ferus) and plains zebras (Equus quagga).

    Science.gov (United States)

    Brubaker, Alexali S; Coss, Richard G

    2015-11-01

    Habituation to humans was an essential component of horse (Equus caballus ferus) domestication, with the nondomestication of zebras (Equus quagga) possibly reflecting an adaptive constraint on habituation. We present the human hunting hypothesis, arguing that ancestral humans hunted African animals, including zebras, long enough to promote a persistent wariness of humans, whereas a briefer period of hunting horses in Central Asia influenced by glacial cycles was unlikely to produce an equally persistent wariness. An alternative habituation to humans hypothesis, prompted by field observations, posits that zebras can habituate well to nonthreatening humans given sufficient exposure. If so, other factors must account for zebra nondomestication. To examine these hypotheses, we compared the flight initiation distances (FIDs) of wild horses in the United States and plains zebras in Africa to a human approaching on foot (N = 87). We compared the flight behavior of both species at sites with low and high exposure to humans (mean humans/acre = .004 and .209, respectively). Analyses revealed a significant interaction (p = .0001) between equid species and level of human exposure. The mean FIDs of horses (146 m) and zebras (105 m) with low human exposure did not differ appreciably (p = .412), but these distances were substantially longer (p < .0001) than those of horses (17 m) and zebras (37 m) with high human exposure that did differ significantly (p < .0001). The finding that plains zebras habituate less completely to humans than horses do might reflect an adaptive response to historical hunting and partly explain their resistance to domestication. (c) 2015 APA, all rights reserved).

  18. Effects of shell morphology on mechanics of zebra and quagga mussel locomotion.

    Science.gov (United States)

    Peyer, Suzanne M; Hermanson, John C; Lee, Carol Eunmi

    2011-07-01

    Although zebra mussels (Dreissena polymorpha) initially colonized shallow habitats within the North American Great Lakes, quagga mussels (Dreissena bugensis) are becoming dominant in both shallow- and deep-water habitats. Shell morphology differs among zebra, shallow quagga and deep quagga mussels but functional consequences of such differences are unknown. We examined effects of shell morphology on locomotion for the three morphotypes on hard (typical of shallow habitats) and soft (characteristic of deep habitats) sedimentary substrates. We quantified morphology using the polar moment of inertia, a parameter used in calculating kinetic energy that describes shell area distribution and resistance to rotation. We quantified mussel locomotion by determining the ratio of rotational (K(rot)) to translational kinetic energy (K(trans)). On hard substrate, K(rot):K(trans) of deep quagga mussels was fourfold greater than for the other morphotypes, indicating greater energy expenditure in rotation relative to translation. On soft substrate, K(rot):K(trans) of deep quagga mussels was approximately one-third of that on hard substrate, indicating lower energy expenditure in rotation on soft substrate. Overall, our study demonstrates that shell morphology correlates with differences in locomotion (i.e. K(rot):K(trans)) among morphotypes. Although deep quagga mussels were similar to zebra and shallow quagga mussels in terms of energy expenditure on sedimentary substrate, their morphology was energetically maladaptive for linear movement on hard substrate. As quagga mussels can possess two distinct morphotypes (i.e. shallow and deep morphs), they might more effectively utilize a broader range of substrates than zebra mussels, potentially enhancing their ability to colonize a wider range of habitats.

  19. Bioaccumulation and effects of perfluorinated compounds (PFCs) in zebra mussels (Dreissena polymorpha).

    Science.gov (United States)

    Fernández-Sanjuan, María; Faria, Melissa; Lacorte, Silvia; Barata, Carlos

    2013-04-01

    Perfluorinated chemicals (PFCs) have been used for many years in numerous industrial products and are known to accumulate in organisms. A recent survey showed that tissue levels of PFCs in aquatic organisms varied among compounds and species being undetected in freshwater zebra mussels Dreissena polymorpha. Here we studied the bioaccumulation kinetics and effects of two major PFCs, perfluorooctane sulfonic acid compound (PFOS) and perfluorooctanoic acid (PFOA), in multixenobiotic transporter activity (MXR) and filtration and oxygen consumption rates in zebra mussel exposed to a range of concentrations of a PCF mixture (1-1,000 μg/L) during 10 days. Results indicate a low potential of the studied PFCs to bioaccumulate in zebra mussel tissues. PFCs altered mussel MXR transporter activity being inhibited at day 1 but not at day 10. Bioaccumulation kinetics of PFCs were inversely related with MXR transporter activity above 9 ng/g wet weight and unrelated at tissue concentration lower than 2 ng/g wet weight suggesting that at high tissue concentrations, these type of compounds may be effluxed out by MXR transporters and as a result have a low potential to be bioaccumulated in zebra mussels. Oxygen consumption rates but not filtering rates were increased in all exposure levels and periods indicating that at environmental relevant concentrations of 1 μg/L, the studied PFCs enhanced oxidative metabolism of mussels. Overall, the results obtained in this study confirm previous findings in the field indicating that an important fraction of PFC accumulated in mussel tissues is eliminated actively by MXR transporters or other processes that are metabolically costly.

  20. Efficacy of Pseudomonas fluorescens (Pf-CL145A) spray dried powder for controlling zebra mussels adhering to test substrates

    Science.gov (United States)

    Luoma, James A.; Severson, Todd J.; Weber, Kerry L.; Mayer, Denise A.

    2015-01-01

    A mobile bioassay trailer was used to assess the efficacy of Pseudomonas fluorescens (Pf-CL145A) spray dried powder (SDP) formulation for controlling zebra mussels (Dreissena polymorpha) from two midwestern lakes: Lake Carlos (Alexandria, Minnesota) and Shawano Lake (Shawano, Wisconsin). The effects of SDP exposure concentration and exposure duration on zebra mussel survival were evaluated along with the evaluation of a benthic injection application technique to reduce the amount of SDP required to induce zebra mortality.

  1. Assessing the potential for fish predation to impact zebra mussels (Dreissena polymorpha): Insight from bioenergetics models

    Science.gov (United States)

    Eggleton, M.A.; Miranda, L.E.; Kirk, J.P.

    2004-01-01

    Rates of annual food consumption and biomass were modeled for several fish species across representative rivers and lakes in eastern North America. Results were combined to assess the relative potential of fish predation to impact zebra mussels (Dreissena polymorpha). Predicted annual food consumption by fishes in southern waters was over 100% greater than that in northern systems because of warmer annual water temperatures and presumed increases in metabolic demand. Although generally increasing with latitude, biomasses of several key zebra mussel fish predators did not change significantly across latitudes. Biomasses of some less abundant fish predators did increase significantly with latitude, but increases were not of the magnitude to offset predicted decreases in food consumption. Our results generally support the premise that fishes in rivers and lakes of the southern United States (U.S.) have inherently greater potential to impact zebra mussels by predation. Our simulations may provide a partial explanation of why zebra mussel invasions have not been as rapid and widespread in southern U.S. waters compared to the Great Lakes region. ?? Blackwell Munksgaard, 2004.

  2. Hudson River Unionids and Zebra Mussels: The Beginning of the End or the End of the Beginning?

    Science.gov (United States)

    Strayer, D. L.; Malcom, H. M.

    2005-05-01

    The invasion of the Hudson River estuary by zebra mussels was followed by steep declines (77 to >99.7%) in populations of all species of native bivalves between 1992 and 1999. Body condition of all unionids, and growth and recruitment of young unionids also declined significantly. Declines in population size and body condition were correlated primarily with the filtration rate of the zebra mussel population, not with fouling of native bivalves by zebra mussels. Samples taken since 2000, however, have shown that populations of all 4 common native bivalves have stabilized or even recovered, although the zebra mussel population has not declined. The mechanisms underlying this apparent reversal of fortune are not clear: recruitment and growth of young mussels have showed limited recovery, but body condition of adults has not. We found no evidence that spatial refuges contributed to this reversal of population declines. Simple statistical models project now that native bivalves may persist at population densities about an order of magnitude below their pre-invasion densities.

  3. Filtration effects of zebra mussels on pathogens and total bacterial burden in the Odra Lagoon (South Baltic).

    Science.gov (United States)

    Daeschlein, G; Fenske, C; Scholz, S; Dahlke, S; Jünger, M; Kramer, A

    2015-01-01

    As a result of their mode of filter feeding, zebra mussels (Dreissena polymorpha Pall.) have been observed to purify natural water bodies and in vitro. Therefore, the possibility of using zebra mussels for water purification was investigated in a slightly brackish water body of a large lagoon. In this study, water samples were taken above, near and at distance from zebra mussel beds (MB) in the Odra Lagoon in North East Germany. Near typical bacterial species like Aeromonas spp. pathogenic bacteria with potential relation to hospital wastewater pollution (Burkholderia cepacia, Staphylococcus aureus, Weeksella spp.) were detected. There were no correlations found between either total bacteria or pathogens and distance to MB and no antimicrobial effect of the mussels could be deduced. For bioremediation in larger water bodies like lagoons, natural zebra MB do not seem to play a major antimicrobial role and the effect of artificial mussel grids especially against hospital pathogens should be investigated.

  4. The Relationship between Plants Used to Sustain Finches (Fringillidae) and Uses for Human Medicine in Southeast Spain

    Science.gov (United States)

    Belda, Antonio; Peiró, Victoriano; Seva, Eduardo

    2012-01-01

    We analyzed plants that are traditionally used by wild bird hunters and breeders to capture and promote captive breeding of Fringillidae (finches or songbirds) in the province of Alicante, Spain. The majority of plants used in songbird breeding have medicinal properties in traditional human medicine (48 different uses); thus, another main goal was to show their relationships with human medical uses. We compiled a list of 97 plant species from 31 botanical families that are used to attract finches and identified 11 different use categories for these plants in finch keeping. The most common uses were for trapping birds and as a source of food for birds in captivity. Cannabis sativa has the greatest cultural importance index (CI = 1.158), and Phalaris canariensis (annual canary grass or alpist) was the most common species used to attract Fringillidae and was used by all informants (n = 158). Most of the 97 species are wild plants and mainly belong to the families Compositae, Gramineae, Cruciferae, and Rosaceae and also have medicinal properties for humans. In the study area, the intensification of agriculture and abandonment of traditional management practices have caused the population of many songbirds to decline, as well as the loss of popular ethnographic knowledge. PMID:22611428

  5. The Relationship between Plants Used to Sustain Finches (Fringillidae and Uses for Human Medicine in Southeast Spain

    Directory of Open Access Journals (Sweden)

    Antonio Belda

    2012-01-01

    Full Text Available We analyzed plants that are traditionally used by wild bird hunters and breeders to capture and promote captive breeding of Fringillidae (finches or songbirds in the province of Alicante, Spain. The majority of plants used in songbird breeding have medicinal properties in traditional human medicine (48 different uses; thus, another main goal was to show their relationships with human medical uses. We compiled a list of 97 plant species from 31 botanical families that are used to attract finches and identified 11 different use categories for these plants in finch keeping. The most common uses were for trapping birds and as a source of food for birds in captivity. Cannabis sativa has the greatest cultural importance index (CI = 1.158, and Phalaris canariensis (annual canary grass or alpist was the most common species used to attract Fringillidae and was used by all informants (=158. Most of the 97 species are wild plants and mainly belong to the families Compositae, Gramineae, Cruciferae, and Rosaceae and also have medicinal properties for humans. In the study area, the intensification of agriculture and abandonment of traditional management practices have caused the population of many songbirds to decline, as well as the loss of popular ethnographic knowledge.

  6. The Relationship between Plants Used to Sustain Finches (Fringillidae) and Uses for Human Medicine in Southeast Spain.

    Science.gov (United States)

    Belda, Antonio; Peiró, Victoriano; Seva, Eduardo

    2012-01-01

    We analyzed plants that are traditionally used by wild bird hunters and breeders to capture and promote captive breeding of Fringillidae (finches or songbirds) in the province of Alicante, Spain. The majority of plants used in songbird breeding have medicinal properties in traditional human medicine (48 different uses); thus, another main goal was to show their relationships with human medical uses. We compiled a list of 97 plant species from 31 botanical families that are used to attract finches and identified 11 different use categories for these plants in finch keeping. The most common uses were for trapping birds and as a source of food for birds in captivity. Cannabis sativa has the greatest cultural importance index (CI = 1.158), and Phalaris canariensis (annual canary grass or alpist) was the most common species used to attract Fringillidae and was used by all informants (n = 158). Most of the 97 species are wild plants and mainly belong to the families Compositae, Gramineae, Cruciferae, and Rosaceae and also have medicinal properties for humans. In the study area, the intensification of agriculture and abandonment of traditional management practices have caused the population of many songbirds to decline, as well as the loss of popular ethnographic knowledge.

  7. The Enigma of Progressively Partial Endoreplication: New Insights Provided by Flow Cytometry and Next-Generation Sequencing

    Czech Academy of Sciences Publication Activity Database

    Hřibová, Eva; Holušová, Kateřina; Trávníček, Pavel; Petrovská, Beáta; Ponert, J.; Šimková, Hana; Kubátová, B.; Jersáková, J.; Čurn, V.; Suda, Jan; Doležel, Jaroslav; Vrána, Jan

    2016-01-01

    Roč. 8, č. 6 (2016), s. 1996-2005 ISSN 1759-6653 R&D Projects: GA ČR GAP506/12/1320; GA MŠk(CZ) LO1204 Institutional support: RVO:61389030 ; RVO:67985939 Keywords : nuclear-dna content * genome size * repetitive dna * zebra finch * chromosome * elimination * endoreduplication * replication * evolution * orchids * cell cycle * DNA replication * EdU * endoreduplication * Ludisia discolor * orchids Subject RIV: EF - Botanics; EF - Botanics (BU-J) Impact factor: 3.979, year: 2016

  8. Hemispheric dominance underlying the neural substrate for learned vocalizations develops with experience

    OpenAIRE

    Chirathivat, Napim; Raja, Sahitya C.; Gobes, Sharon M. H.

    2015-01-01

    Many aspects of song learning in songbirds resemble characteristics of speech acquisition in humans. Genetic, anatomical and behavioural parallels have most recently been extended with demonstrated similarities in hemispheric dominance between humans and songbirds: the avian higher order auditory cortex is left-lateralized for processing song memories in juvenile zebra finches that already have formed a memory of their fathers? song, just like Wernicke?s area in the left hemisphere of the hum...

  9. Feeder density enhances house finch disease transmission in experimental epidemics.

    Science.gov (United States)

    Moyers, Sahnzi C; Adelman, James S; Farine, Damien R; Thomason, Courtney A; Hawley, Dana M

    2018-05-05

    Anthropogenic food provisioning of wildlife can alter the frequency of contacts among hosts and between hosts and environmental sources of pathogens. Despite the popularity of garden bird feeding, few studies have addressed how feeders influence host contact rates and disease dynamics. We experimentally manipulated feeder density in replicate aviaries containing captive, pathogen-naive, groups of house finches ( Haemorhous mexicanus ) and continuously tracked behaviours at feeders using radio-frequency identification devices. We then inoculated one bird per group with Mycoplasma gallisepticum (Mg), a common bacterial pathogen for which feeders are fomites of transmission, and assessed effects of feeder density on house finch behaviour and pathogen transmission. We found that pathogen transmission was significantly higher in groups with the highest density of bird feeders, despite a significantly lower rate of intraspecific aggressive interactions relative to the low feeder density groups. Conversely, among naive group members that never showed signs of disease, we saw significantly higher concentrations of Mg-specific antibodies in low feeder density groups, suggesting that birds in low feeder density treatments had exposure to subclinical doses of Mg. We discuss ways in which the density of garden bird feeders could play an important role in mediating the intensity of Mg epidemics.This article is part of the theme issue 'Anthropogenic resource subsidies and host-parasite dynamics in wildlife'. © 2018 The Author(s).

  10. Home range sizes for burchell's zebra equus burchelli antiquorum from the Kruger National Park

    Directory of Open Access Journals (Sweden)

    G.L. Smuts

    1975-07-01

    Full Text Available Annual home range sizes were determined for 49 marked zebra family groups in the Kruger National Park. Sizes varied from 49 to 566 sq. km, the mean for the Park being 164 square kilometre. Mean home range sizes for different zebra sub-populations and biotic areas were found to differ considerably. Present herbivore densities have not influenced intra- and inter-specific tolerance levels to the extent that home range sizes have increased. Local habitat conditions, and particularly seasonal vegetational changes, were found to have the most profound influence on the shape and mean size of home ranges. The large home range sizes obtained in the Kruger Park, when compared to an area such as the Ngorongoro Crater, can be ascribed to a lower carrying capacity with respect to zebra, large portions of the habitat being sub-optimal, either seasonally or annually.

  11. Development of a molecular diagnostic system to discriminate Dreissena polymorpha (zebra mussel) and Dreissena bugensis (quagga mussel)

    Science.gov (United States)

    Hoy, M.S.; Kelly, K.; Rodriguez, R.J.

    2010-01-01

    A 3-primer PCR system was developed to discriminate invasive zebra (Dreissena polymorpha) and quagga (Dreissena bugensis) mussel. The system is based on: 1) universal primers that amplifies a region of the nuclear 28s rDNA gene from both species and 2) a species-specific primer complementary to either zebra or quagga mussel. The species-specific primers bind to sequences between the binding sites for the universal primers resulting in the amplification of two products from the target species and one product from the nontarget species. Therefore, nontarget products are positive amplification controls. The 3-primer system accurately discriminated zebra and quagga mussels from seven geographically distinct populations.

  12. Potential impacts of ENDF/B-V on critical experiment analysis based on ZEBRA-8 criticals

    Energy Technology Data Exchange (ETDEWEB)

    Choong, T S

    1982-06-01

    The ZEBRA-8 series of null-zone measurements featured a different neutron spectrum for each assembly. The experiments were designed for the purpose of basic data testing. The series cover a range of spectra both harder and softer than that for the LMFBR. The potential impacts of the newly released ENDF/BV cross section library on LMFBR critical exeriment analysis are discussed based on analysis of ZEBRA-8 series.

  13. Scanning electron microscopy of Strongylus spp. in zebra.

    Science.gov (United States)

    Els, H J; Malan, F S; Scialdo-Krecek, R C

    1983-12-01

    The external ultrastructure of the anterior and posterior extremities of the nematodes, Strongylus asini , Strongylus vulgaris, Strongylus equinus and Strongylus edentatus, was studied with scanning electron microscopy (SEM). Fresh specimens of S. asini were collected from the caecum, ventral colon and vena portae of Equus burchelli and Equus zebra hartmannae ; S. vulgaris from the caecum, colon and arteria ileocolica of E. burchelli ; S. equinus from the ventral colon of E. z. hartmannae and S. edentatus from the caecum and ventral colon of both zebras , during surveys of parasites in zebras in the Etosha Game Reserve, South West Africa/Namibia, and the Kruger National Park, Republic of South Africa. The worms were cleaned, fixed and mounted by standard methods and photographed in a JEOL JSM - 35C scanning electron microscope (SEM) operating at 12kV . The SEM showed the following differences: the tips of the external leaf-crowns varied and were fine and delicate in S. asini , coarse and broad in S. vulgaris and, in S. equinus and S. edentatus, closely adherent, separating into single elements for half their length. The excretory pores showed only slight variation, and the morphology of the copulatory bursae did not differ from those seen with light microscopy. The genital cones differed markedly: S. asini had a ventral triangular projection and laterally 2 finger-like projections: in S. vulgaris there were numerous bosses on the lateral and ventral aspects of the cone; in S. equinus 2 finger-like processes projected laterocaudally ; and in S. edentatus 2 pairs of papilla-like processes projected laterally on the ventral aspects, and a pair of rounded projections and a pair of hair-like structures adorned the dorsal aspects.(ABSTRACT TRUNCATED AT 250 WORDS)

  14. Modeling the Role of Zebra Mussels in the Proliferation of Blue-green Algae in Saginaw Bay, Lake Huron

    Science.gov (United States)

    Under model assumptions from Saginaw Bay 1991, selective rejection of blue-green algae by zebra mussels appears to be a necessary factor in the enhancement of blue-green algae production in the presence of zebra mussels. Enhancement also appears to depend on the increased sedime...

  15. Comparative biology of zebra mussels in Europe and North America: an overview

    Science.gov (United States)

    Mackie, Gerald L.; Schloesser, Don W.

    1996-01-01

    SYNOPSIS. Since the discovery of the zebra mussel, Dreissena polymorpha, in the Great Lakes in 1988 comparisons have been made with mussel populations in Europe and the former Soviet Union. These comparisons include: Population dynamics, growth and mortality rates, ecological tolerances and requirements, dispersal rates and patterns, and ecological impacts. North American studies, mostly on the zebra mussel and a few on a second introduced species, the quagga mussel, Dreissena bugensis, have revealed some similarities and some differences. To date it appears that North American populations of zebra mussels are similar to European populations in their basic biological characteristics, population growth and mortality rates, and dispersal mechanisms and rates. Relative to European populations differences have been demonstrated for: (1) individual growth rates; (2) life spans; (3) calcium and pH tolerances and requirements; (4) potential distribution limits; and (5) population densities of veligers and adults. In addition, studies on the occurrence of the two dreissenid species in the Great Lakes are showing differences in their modes of life, depth distributions, and growth rates. As both species spread throughout North America, comparisons between species and waterbodies will enhance our ability to more effectively control these troublesome species.

  16. Immunological investments reflect parasite abundance in island populations of Darwin's finches.

    OpenAIRE

    Lindström, Karin M.; Foufopoulos, Johannes; Pärn, Henrik; Wikelski, Martin

    2004-01-01

    The evolution of parasite resistance can be influenced by the abundance of parasites in the environment. However, it is yet unresolved whether vertebrates change their investment in immune function in response to variation in parasite abundance. Here, we compare parasite abundance in four populations of small ground finches (Geospiza fuliginosa) in the Galapagos archipelago. We predicted that populations exposed to high parasite loads should invest more in immune defence, or alternatively use...

  17. Zebra mussels (Dreissena polymorpha) limit food for larval fish (Pimephales promelas) in turbulent systems: A bioenergetics analysis

    Science.gov (United States)

    Bartsch, L.A.; Richardson, W.B.; Sandheinrich, M.B.

    2003-01-01

    We conducted a factorial experiment, in outdoor mesocosms, on the effects of zebra mussels and water column mixing (i.e., turbulence) on the diet, growth, and survival of larval fathead minnows (Pimephales promelas). Significant (P zebra mussels, whereas mortality was 37% in treatment with turbulence and 17% and 18% in the zebra mussels treatment, and the control, respectively. The size of individual fish was significantly different among treatments at the end of the experiment and was inversely related to survival. Levels of trophic resources (i.e., phyto and zooplankton) varied among treatments and were treatment specific. Turbulent mixing facilitated removal of phytoplankton by zebra mussels by making the entire water column of the tanks available to these benthic filter feeders. Early in the experiment (Day = 0 to 14) the physical process of turbulent mixing likely caused a reduction in standing stocks of zooplankton. The interactive effect of turbulence and mussels reduced copepod and rotifer stocks, through physical processes and through filtration by zebra mussels, relative to the turbulence treatment. The reductions in the number of total zooplankton in the turbulent mixing mesocosms and the further reduction of rotifer and copepod in the turbulence and mussels treatment coincided with a period of increased reliance of larval fathead minnows on these prey. Estimates of consumption from bioenergetics modeling and measured prey standing stocks indicated caloric resources of suitable prey in turbulence treatments during the early weeks of the experiment were insufficient to prevent starvation. Early mortality in the turbulence and mussels treatment likely released surviving fish from intense intraspecific competition and resulted in higher individual growth rates. A combination of high abundance of zebra mussels in an environment with a well-mixed water column can have significant effects on larval fish survival and growth.

  18. The Songbird Neurogenomics (SoNG Initiative: Community-based tools and strategies for study of brain gene function and evolution

    Directory of Open Access Journals (Sweden)

    Lewin Harris A

    2008-03-01

    Full Text Available Abstract Background Songbirds hold great promise for biomedical, environmental and evolutionary research. A complete draft sequence of the zebra finch genome is imminent, yet a need remains for application of genomic resources within a research community traditionally focused on ethology and neurobiological methods. In response, we developed a core set of genomic tools and a novel collaborative strategy to probe gene expression in diverse songbird species and natural contexts. Results We end-sequenced cDNAs from zebra finch brain and incorporated additional sequences from community sources into a database of 86,784 high quality reads. These assembled into 31,658 non-redundant contigs and singletons, which we annotated via BLAST search of chicken and human databases. The results are publicly available in the ESTIMA:Songbird database. We produced a spotted cDNA microarray with 20,160 addresses representing 17,214 non-redundant products of an estimated 11,500–15,000 genes, validating it by analysis of immediate-early gene (zenk gene activation following song exposure and by demonstrating effective cross hybridization to genomic DNAs of other songbird species in the Passerida Parvorder. Our assembly was also used in the design of the "Lund-zfa" Affymetrix array representing ~22,000 non-redundant sequences. When the two arrays were hybridized to cDNAs from the same set of male and female zebra finch brain samples, both arrays detected a common set of regulated transcripts with a Pearson correlation coefficient of 0.895. To stimulate use of these resources by the songbird research community and to maintain consistent technical standards, we devised a "Community Collaboration" mechanism whereby individual birdsong researchers develop experiments and provide tissues, but a single individual in the community is responsible for all RNA extractions, labelling and microarray hybridizations. Conclusion Immediately, these results set the foundation for a

  19. Ethological investigations on a herd of plains zebra in a safari park: Time-budgets, reproduction and food competition

    NARCIS (Netherlands)

    Schilder, M.B.H.; Boer, P.L.

    The social organization of a herd of 25 plains zebras under safari park conditions and the time-budgets of 18 individuals from this herd were investigated. The zebras had organized themselves in harem groups. Stallions appeared to spend more time acting socially than did other sex-age classes and

  20. Experimental evidence for millisecond activation timescales using the Fast IN Chamber (FINCH) measurements

    Science.gov (United States)

    Bundke, U.; Jaenicke, R.; Klein, H.; Nillius, B.; Reimann, B.; Wetter, T.; Bingemer, H.

    2009-04-01

    Ice formation in clouds is a subject of great practical and fundamental importance since the occurrence of ice particle initializes dramatic changes in the microphysical structure of the cloud, which finally ends in the formation of precipitation. The initially step of ice formation is largely unknown. Homogenous nucleation of ice occurs only below -40 °C. If an ice nucleus (IN) is present, heterogeneous nucleation may occur at higher temperature. Here deposition freezing, condensation and immersion freezing as well as contact freezing are known. Also growth rates of ice particles are known as function of crystal surface properties, temperature and super saturation. Timescales for homogenous freezing activation in the order of 0.01 seconds and nucleation rates have been measured by Anderson et al. (1980) and Hagen et al., (1981) using their expansion cloud chamber. This contribution of deposition mode freezing measurements by the ice nucleus counter FINCH presents evidence that the activation timescale of this freezing mode is in the order of 1E-3 seconds. FINCH is an Ice Nucleus counter which activates IN in a supersaturated environment at freezing temperatures. The activation conditions are actively controlled by mixing three gas flows (aerosol, particle-free cold-dry and warm-humid flows).See Bundke et al. 2008 for details. In a special operation mode of FINCH we are able to produce a controlled peak super saturation in the order of 1 ms duration. For several test aerosols the results observed in this particular mode are comparable to normal mode operations, where the maximum super saturation remains for more than a second, thus leading to the conclusion that the time for activation is in the order of 1ms or less. References: R.J. Anderson et al, "A Study of Homogeneous Condensation Freezing Nucleation of Small Water Droplets in an Expansion Cloud Chamber, Journal of the Atmospheric Sciences, Vol. 37, 2508-2520, 1980 U.Bundke et al., "The fast Ice Nucleus

  1. Cultivation of zebra mussels (Dreissena polymorpha) within their invaded range to improve water quality in reservoirs.

    Science.gov (United States)

    McLaughlan, C; Aldridge, D C

    2013-09-01

    Algal and cyanobacterial blooms in reservoirs are driven by nutrient enrichment and may present economic and conservation challenges for water managers. Current approaches such as suppression of algal growth with barley straw, ferric dosing or manipulation of fish stocks have not yielded long term successes. A possibility that has sparked growing interest is the encouragement and cultivation of natural filter feeders, such as mussels, which remove suspended matter from the water and reduce nutrient levels through biodeposition and assimilation. This review focusses on the zebra mussel (Dreissena polymorpha) as a tool for enhancement of water quality in reservoirs. Native to the Ponto-Caspian region, this species has invaded many lakes and reservoirs across North America and Western Europe, where it occurs in very high densities. While purposeful introduction of a non-native species into new sites is socially unacceptable, we investigate the possible benefits of encouraging increased abundance of zebra mussels in sites where the species is already established. We estimate that the annual nitrogen and phosphorus input into a large UK reservoir (Grafham Water) could be assimilated into zebra mussel biomass by encouraging settlement onto 3075 m and 1400 m of commercial mussel ropes, respectively. While zebra mussel cultivation has an incredible capacity to push eutrophic systems towards a clear water state, there are many risks associated with encouraging an invasive species, even within sites where it has already established. The zebra mussel is a prominent biofouler of native unionid mussels and raw water pipes, it changes the physical characteristics of the places it inhabits, in sites low in phosphorus it can be responsible for toxic cyanobacterial blooms, it alters nutrient cycling and community structure and it can have negative impacts on amenity value. Increased propagule pressure from elevated numbers of veliger larvae in the water column may increase the risk

  2. The quagga and science: what does the future hold for this extinct zebra?

    Science.gov (United States)

    Heywood, Peter

    2013-01-01

    Quaggas, partially striped zebras from South Africa, have had major impacts on science. In the 19th century, the results of mating between a quagga stallion and a horse mare influenced thinking about mechanisms of inheritance for more than 70 years. In the 20th century, tissue from a quagga yielded the first DNA of an extinct organism to be cloned and sequenced. Selective breeding of plains zebras in South Africa has produced animals whose coat coloration resembles that of some quaggas. This raises the intriguing possibility that quaggas may once again be the focus of scientific investigations.

  3. Zebra layers and Paleoenvironment of Late Miocene Stratum in the ...

    Indian Academy of Sciences (India)

    26

    paleotopography rather than soil creep, and that they were not deposited in a .... Four groups of orientated samples were collected from the Zebra layers of the ..... However, it can take hundreds or even thousands of years to develop a layer.

  4. The Influence of the Zebra Mussel (Dreisena Polymorhpa) on Magnesium and Calcium Concentration in Water

    OpenAIRE

    Wojtal-Frankiewicz Adrianna; Frankiewicz Piotr

    2011-01-01

    In this study we examined changes in magnesium and calcium ion concentrations depending on Zebra Mussel biomass, pH values and temperature. We performed field experiments in years with different weather conditions using twelve 200 litre polycarbonate containers filled with 150 litres of non-filtered water from lowland, eutrophic reservoirs. Three treatments of the experiment were represented by: Phyto control with non-filtered water, Phyto+Dreis A with Zebra Mussel biomass of 500 g/m2, and Ph...

  5. Selective grazing by adults and larvae of the zebra mussel (Dreissena polymorpha): application of flow cytometry to natural seston

    NARCIS (Netherlands)

    Dionisio Pires, L.M.; Jonker, R.R.; Donk, E.van; Laanbroek, H.J.

    2004-01-01

    1. Selective grazing of adults and larvae of the zebra mussel (Dreissena polymorpha) on phytoplankton and detritus from both laboratory cultures and natural seston was quantified using flow cytometry. 2. Mean clearance rate of adult zebra mussels was higher on a mixture of the green

  6. LETHALITY OF PSEUDOMONAS FLUORESCENS STRAIN CLO145A TO THE 2 ZEBRA MUSSEL SPECIES PRESENT IN NORTH AMERICA

    International Nuclear Information System (INIS)

    Molloy, Daniel P.

    2001-01-01

    These experiments indicated that bacterial strain CL0145A of Pseudomonas fluorescens is equally lethal to the 2 zebra mussel species present in North America, Dreissena polymorpha and Dreissena bugensis. Thus, this bacterial strain should be equally effective at killing zebra mussels in power plant pipes, irrespective of which species is present

  7. LETHALITY OF PSEUDOMONAS FLUORESCENS STRAIN CLO145A TO THE 2 ZEBRA MUSSEL SPECIES PRESENT IN NORTH AMERICA

    Energy Technology Data Exchange (ETDEWEB)

    Daniel P. Molloy

    2001-10-28

    These experiments indicated that bacterial strain CL0145A of Pseudomonas fluorescens is equally lethal to the 2 zebra mussel species present in North America, Dreissena polymorpha and Dreissena bugensis. Thus, this bacterial strain should be equally effective at killing zebra mussels in power plant pipes, irrespective of which species is present.

  8. Development of a molecular diagnostic system to discriminate Dreissena polymorpha (zebra mussel) and Dreissena bugensis (quagga mussel).

    Science.gov (United States)

    Hoy, Marshal S; Kelly, Kevin; Rodriguez, Rusty J

    2010-01-01

    A 3-primer PCR system was developed to discriminate invasive zebra (Dreissena polymorpha) and quagga (Dreissena bugensis) mussel. The system is based on: 1) universal primers that amplifies a region of the nuclear 28s rDNA gene from both species and 2) a species-specific primer complementary to either zebra or quagga mussel. The species-specific primers bind to sequences between the binding sites for the universal primers resulting in the amplification of two products from the target species and one product from the nontarget species. Therefore, nontarget products are positive amplification controls. The 3-primer system accurately discriminated zebra and quagga mussels from seven geographically distinct populations. Published 2009. This article is a US Government work and is the public domain in the USA.

  9. The zebra mussel: US utility implications

    International Nuclear Information System (INIS)

    McMahon, R.F.

    1990-11-01

    Dreissena polymorpha, the freshwater macrofouling zebra mussel, was introduced to Lake St. Clair, near Detroit, Michigan, in 1985. It has since spread throughout Lake Erie. Its planktonic veliger larval stage disperses on water currents and adults are transported by human and natural vectors, making it likely to spread throughout most of the United States and southern Canada except for the southwestern and southern United State, where summer water temperatures are above tolerated levels. Veligers enter raw water systems on intake currents to settle and grow to adults attached by secreted byssal threads to hard surfaces. Accumulations of adults impede flow, aggravate sedimentation and corrosion, and foul small-diameter components. Settlement occurs at flow velocities less than 1.5--2.0 m/sec. Mussels can reduce effective pipe diameters and foul intake structures, steam condensers, heat exchangers, fire protection systems, and cooling tower basins. Establishment of mussels in raw water systems should be prevented because subsequent removal is difficult and expensive. Mitigation procedures include manual removal, robotic cleaning, thermal backwashing, water jetting, application of molluscicides, and possibly line pigging and acidic chemical cleaning. Control technologies include oxidizing and non-oxidizing molluscicides, robotic cleaning, shell strainers, exposure of veligers to high voltage electrical fields, thermal backwashing and sand-filtration. The United States power industry can utilize extensive European experience with this species and domestic experience with the Asian clam in its development of effective controls for zebra mussel fouling

  10. Selective grazing by adults and larvae of the zebra mussel (Dreissena polymorpha): application of flow cytometry to natural seston

    NARCIS (Netherlands)

    Pires, L.M.D.; Jonker, R.M.; Van Donk, E.; Laanbroek, H.J.

    2004-01-01

    1. Selective grazing of adults and larvae of the zebra mussel (Dreissena polymorpha) on phytoplankton and detritus from both laboratory cultures and natural seston was quantified using flow cytometry. 2. Mean clearance rate of adult zebra mussels was higher on a mixture of the green alga Scenedesmus

  11. Genetic diversity of the Ethiopian Grevy's zebra (Equus grevyi) populations that includes a unique population of the Alledeghi Plain.

    Science.gov (United States)

    Kebede, Fanuel; Rosenbom, Sonia; Khalatbari, Leili; Moehlman, Patricia D; Beja-Pereira, Albano; Bekele, Afework

    2016-01-01

    The endangered Grevy's Zebra (Equus grevyi) is confined to the Horn of Africa, specifically Ethiopia and Kenya. It is threatened by habitat loss and fragmentation due to human encroachment of historic range. Knowledge of population genetics is essential for the development of appropriate conservation actions and management. The focus of this study was to assess the heterogeneity and genetic distinctiveness of the two Grevy's zebra populations in Ethiopia. Non-invasive fecal samples (N = 120) were collected during 2009-2010 from Grevy's zebra populations in the Alledeghi Wildlife Reserve and the Sarite area, Ethiopia. Analyses of a 329 bp of the mtDNA control region of 47 sequences, revealed the existence of two unreported haplotypes in the northern population of Alledeghi, that were not shared with the southern population of Sarite. The Sarite population is contiguous with the Grevy's zebra population in Kenya. The nucleotide diversity levels found in both the populations are extremely low.

  12. A dominance shift from the zebra mussel to the invasive quagga mussel may alter the trophic transfer of metals.

    Science.gov (United States)

    Matthews, Jonathan; Schipper, Aafke M; Hendriks, A Jan; Yen Le, T T; Bij de Vaate, Abraham; van der Velde, Gerard; Leuven, Rob S E W

    2015-08-01

    Bioinvasions are a major cause of biodiversity and ecosystem changes. The rapid range expansion of the invasive quagga mussel (Dreissena rostriformis bugensis) causing a dominance shift from zebra mussels (Dreissena polymorpha) to quagga mussels, may alter the risk of secondary poisoning to predators. Mussel samples were collected from various water bodies in the Netherlands, divided into size classes, and analysed for metal concentrations. Concentrations of nickel and copper in quagga mussels were significantly lower than in zebra mussels overall. In lakes, quagga mussels contained significantly higher concentrations of aluminium, iron and lead yet significantly lower concentrations of zinc66, cadmium111, copper, nickel, cobalt and molybdenum than zebra mussels. In the river water type quagga mussel soft tissues contained significantly lower concentrations of zinc66. Our results suggest that a dominance shift from zebra to quagga mussels may reduce metal exposure of predator species. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Temporal and spatial variation in Hg accumulation in zebra mussels (Dreissena polymorpha): possible influences of DOC and diet.

    Science.gov (United States)

    Kraemer, Lisa D; Evans, Douglas; Dillon, Peter J

    2013-05-01

    Zebra mussels (Dreissena polymorpha) are filter feeders located near the base of the foodweb and these animals are able to utilize a variety of carbon sources that may also vary seasonally. We conducted both a spatial and a temporal study in order to test the hypotheses: (1) dissolved organic carbon (DOC) concentrations influence Hg accumulation in zebra mussels sampled from a series of lakes and (2) seasonal variations in diet influence Hg accumulation. In the spatial study, we found a significant negative relationship between Hg concentrations and DOC concentrations, suggesting an influence of DOC on Hg bioaccumulation. In the temporal study, we used stable isotope ratios of nitrogen (δ(15)N) and carbon (δ(13)C) as ecological tools to provide a temporally integrated description of the feeding ecology of zebra mussels. Both δ(15)N and δ(13)C varied seasonally in a similar manner: more depleted values occurred in the summer and more enriched values occurred in the fall. Mercury concentrations also varied significantly over the year, with highest concentrations occurring in the summer, followed by a progressive decrease in concentrations into the fall. The C/N ratio of zebra mussels also varied significantly over the year with the lowest values occurring mid-summer and then values increased in the fall and winter, suggesting that there was significant variation in lipid stores. These results indicate that in addition to any effect of seasonal dietary changes, seasonal variation in energy stores also appeared to be related to Hg levels in the zebra mussels. Collectively results from this study suggest that DOC concentrations, seasonal variation in diet and seasonal depletion of energy stores are all important variables to consider when understanding Hg accumulation in zebra mussels. Copyright © 2013 Elsevier Inc. All rights reserved.

  14. Zebra mussels enter the compost pile

    Energy Technology Data Exchange (ETDEWEB)

    1992-08-01

    Zebra mussels, introduced accidentally into the Great Lakes, are overpopulating at phenomenal rates, especially in Lake Erie, where they damage oyster beds, foster excessive algae growth and cling to boats. They also clog the intake pipes of city water systems and power generating plants. The expense of cleaning intake screens is considerable, since they have to be physically removed and cleaned. Then the mussels must be disposed of, costing some power plants as much as $50,000 a year to landfill, says Wayne Koser of the Michigan Department of Natural Resources.

  15. Will the Displacement of Zebra Mussels by Quagga Mussels Increase Water Clarity in Shallow Lakes during Summer? Results from a Mesocosm Experiment

    OpenAIRE

    Mei, Xueying; Zhang, Xiufeng; Kassam, Sinan-Saleh; Rudstam, Lars G.

    2016-01-01

    Zebra mussels (Dreissena polymorpha) are known to increase water clarity and affect ecosystem processes in invaded lakes. During the last decade, the conspecific quagga mussels (D. rostriformis bugensis) have displaced zebra mussels in many ecosystems including shallow lakes such as Oneida Lake, New York. In this study, an eight-week mesocosm experiment was conducted to test the hypothesis that the displacement of zebra mussels by quagga mussels leads to further decreases in phytoplankton and...

  16. [Resection of the recurrent third branchial fistula under gastroscope with assistance of yellow zebra guidewire].

    Science.gov (United States)

    Feng, X; Huang, Z C; Tao, F; Ou, X L

    2016-02-01

    To investigate clinical aspects and a new operative method for resecting third branchial fistula. The clinical aspects of 4 patients with third branchial fistula were retrospectively analyzed. It is difficult to locate the inner orifice of fistula through neck path due to tiny diameter of inner orifice. The inner orifice could be found and closed effectively by inserting yellow zebra guidewire from sinus piriformis with gastroscope. The mucous membrane of sinus piriformis could not be damaged due to the soft pointed end of yellow zebra guidewire. 4 cases were treated successfully without pharyngeal fistula or recurrent laryngeal nerve injury. No recurrent infections were found in all cases with follows-up of 6-66 months. Ineffectiveness of radiography with meglumine diatrizoate or oral administration of methylene blue before operation indicates tiny fistula. In this case, resection of third branchial fistula with the assistance of gastroscope and yellow zebra guidewire under general anesthesia can be performed. This innovative method of diagnosis and treatment is worth of application clinically.

  17. A food web modeling analysis of a Midwestern, USA eutrophic lake dominated by non-native Common Carp and Zebra Mussels

    Science.gov (United States)

    Colvin, Michael E.; Pierce, Clay; Stewart, Timothy W.

    2015-01-01

    Food web modeling is recognized as fundamental to understanding the complexities of aquatic systems. Ecopath is the most common mass-balance model used to represent food webs and quantify trophic interactions among groups. We constructed annual Ecopath models for four consecutive years during the first half-decade of a zebra mussel invasion in shallow, eutrophic Clear Lake, Iowa, USA, to evaluate changes in relative biomass and total system consumption among food web groups, evaluate food web impacts of non-native common carp and zebra mussels on food web groups, and to interpret food web impacts in light of on-going lake restoration. Total living biomass increased each year of the study; the majority of the increase due to a doubling in planktonic blue green algae, but several other taxa also increased including a more than two-order of magnitude increase in zebra mussels. Common carp accounted for the largest percentage of total fish biomass throughout the study even with on-going harvest. Chironomids, common carp, and zebra mussels were the top-three ranking consumer groups. Non-native common carp and zebra mussels accounted for an average of 42% of the total system consumption. Despite the relatively high biomass densities of common carp and zebra mussel, food web impacts was minimal due to excessive benthic and primary production in this eutrophic system. Consumption occurring via benthic pathways dominated system consumption in Clear Lake throughout our study, supporting the argument that benthic food webs are significant in shallow, eutrophic lake ecosystems and must be considered if ecosystem-level understanding is to be obtained.

  18. Organotins in zebra mussels (Dreissena polymorpha) and sediments of the Quebec City Harbour area of the St. Lawrence River.

    Science.gov (United States)

    Regoli, L; Chan, H M; de Lafontaine, Y; Mikaelian, I

    2001-07-01

    Toxic antifouling agents such as tributyltin (TBT) and triphenyltin (TPT) have been released in aquatic ecosystems through the use of antifouling paint applied to ship hulls, pleasure crafts and fish nets and these compounds can bioaccumulate in aquatic organisms. The purpose of this study was 1) to assess the extent of the distribution of organotins from a contaminated marina to the St. Lawrence River system by measuring organotin concentrations in zebra mussels (Dreissena polymorpha) and in sediments collected from 9 sites along the St. Lawrence River near Quebec City in July 1998, and 2) to examine the histopathological condition of zebra mussel tissues from these sites. TBT concentrations in zebra mussels were between 37 and 1078 ng Sn g(-1) wet weight, with the highest value found in the Bassin Louise marina. Elevated concentrations were also found in two other marinas. The concentrations decreased sharply to background levels just outside the marinas. All butyltins were detected in all sediments analysed, with highest values found in the Bassin Louise marina. Phenyltins were detected in three of the nine sites in low concentrations (zebra mussels. There was a significant correlation between TBT in sediments and mussels. Gonadal development of zebra mussels varied largely between sites, and was negatively associated to TBT levels in mussel tissue. This study shows that TBT contamination remains a problem in localised freshwater sectors of the St. Lawrence River.

  19. Differentiation of sympatric zebra and quagga mussels in ecotoxicological studies: A comparison of morphometric data, gene expression, and body metal concentrations.

    Science.gov (United States)

    Kerambrun, E; Delahaut, L; Geffard, A; David, E

    2018-06-15

    The zebra mussel is among the best studied freshwater molluscs in ecotoxicology, but information on the quagga mussel is lacking. Considering its potential spread, we selected a river in France in which zebra and quagga mussels coexisted, and then we used genetic markers to differentiate the two species and compared morphological parameters. cDNA sequencing assays of ten genes already used in zebra mussels were performed on quagga mussels to obtain functional specific primers. Then we analyzed the expression of genes involved in cellular metabolic activities (Cytochrome-c-oxidase - cox, and ATP synthase - atp), detoxification processes (Glutathione-S-Transferase - gst), oxidative stress (Catalase - cat), and digestive functions (Amylase - amy) on the two species. Whereas morphometric analysis underlined similarities in shape between the two species, relative gene expression profiles and metal concentrations evidenced strong differences. Quagga mussels notably presented half as high concentrations in Cd and Pb, two particularly toxic elements, as zebra mussels. These results imply that i) particular attention should be paid to properly distinguish the two species considering their similar external appearance, and ii) zebra mussels cannot be replaced by quagga mussels in ecotoxicological studies without preliminary investigations on biomarker response patterns. To our knowledge, this study is the first to have undertaken such an approach in gene expression analysis in quagga mussels, and more generally to have compared such biomarker responses of zebra and quagga mussels in the field. Copyright © 2018 Elsevier Inc. All rights reserved.

  20. A Landscape-Scale, Applied Fire Management Experiment Promotes Recovery of a Population of the Threatened Gouldian Finch, Erythrura gouldiae, in Australia's Tropical Savannas.

    Directory of Open Access Journals (Sweden)

    Sarah Legge

    Full Text Available Fire is an integral part of savanna ecology and changes in fire patterns are linked to biodiversity loss in savannas worldwide. In Australia, changed fire regimes are implicated in the contemporary declines of small mammals, riparian species, obligate-seeding plants and grass seed-eating birds. Translating this knowledge into management to recover threatened species has proved elusive. We report here on a landscape-scale experiment carried out by the Australian Wildlife Conservancy (AWC on Mornington Wildlife Sanctuary in northwest Australia. The experiment was designed to understand the response of a key savanna bird guild to fire, and to use that information to manage fire with the aim of recovering a threatened species population. We compared condition indices among three seed-eating bird species--one endangered (Gouldian finch and two non-threatened (long-tailed finch and double-barred finch--from two large areas (> 2,830 km2 with initial contrasting fire regimes ('extreme': frequent, extensive, intense fire; versus 'benign': less frequent, smaller, lower intensity fires. Populations of all three species living with the extreme fire regime had condition indices that differed from their counterparts living with the benign fire regime, including higher haematocrit levels in some seasons (suggesting higher levels of activity required to find food, different seasonal haematocrit profiles, higher fat scores in the early wet season (suggesting greater food uncertainty, and then lower muscle scores later in the wet season (suggesting prolonged food deprivation. Gouldian finches also showed seasonally increasing stress hormone concentrations with the extreme fire regime. Cumulatively, these patterns indicated greater nutritional stress over many months for seed-eating birds exposed to extreme fire regimes. We tested these relationships by monitoring finch condition over the following years, as AWC implemented fire management to produce the 'benign

  1. A Landscape-Scale, Applied Fire Management Experiment Promotes Recovery of a Population of the Threatened Gouldian Finch, Erythrura gouldiae, in Australia's Tropical Savannas.

    Science.gov (United States)

    Legge, Sarah; Garnett, Stephen; Maute, Kim; Heathcote, Joanne; Murphy, Steve; Woinarski, John C Z; Astheimer, Lee

    2015-01-01

    Fire is an integral part of savanna ecology and changes in fire patterns are linked to biodiversity loss in savannas worldwide. In Australia, changed fire regimes are implicated in the contemporary declines of small mammals, riparian species, obligate-seeding plants and grass seed-eating birds. Translating this knowledge into management to recover threatened species has proved elusive. We report here on a landscape-scale experiment carried out by the Australian Wildlife Conservancy (AWC) on Mornington Wildlife Sanctuary in northwest Australia. The experiment was designed to understand the response of a key savanna bird guild to fire, and to use that information to manage fire with the aim of recovering a threatened species population. We compared condition indices among three seed-eating bird species--one endangered (Gouldian finch) and two non-threatened (long-tailed finch and double-barred finch)--from two large areas (> 2,830 km2) with initial contrasting fire regimes ('extreme': frequent, extensive, intense fire; versus 'benign': less frequent, smaller, lower intensity fires). Populations of all three species living with the extreme fire regime had condition indices that differed from their counterparts living with the benign fire regime, including higher haematocrit levels in some seasons (suggesting higher levels of activity required to find food), different seasonal haematocrit profiles, higher fat scores in the early wet season (suggesting greater food uncertainty), and then lower muscle scores later in the wet season (suggesting prolonged food deprivation). Gouldian finches also showed seasonally increasing stress hormone concentrations with the extreme fire regime. Cumulatively, these patterns indicated greater nutritional stress over many months for seed-eating birds exposed to extreme fire regimes. We tested these relationships by monitoring finch condition over the following years, as AWC implemented fire management to produce the 'benign' fire regime

  2. Examining Natural Selection by Sketching and Making Models of the Finches of the Galapagos Islands

    Science.gov (United States)

    Pittman, Phoebe J. Z.; Teske, Jolene K.

    2017-01-01

    This practical lesson describes how students in six eighth grade science classes participated in a lesson combining the National Core Arts Standards with the Next Generation Science Standards. The goal of the lesson was to provide visual representations of finch beak form and function so students could better understand genetic variation and how…

  3. Analysis of Western Australian zebra rock

    International Nuclear Information System (INIS)

    Clark, M.J.; Cashion, J.D.

    2000-01-01

    Full text: Zebra rock is a striking rock from the Ord River area of Western Australia which contains regularly spaced white and red-brown bands or rods. Its ease of working has made it popular for use in ornaments and costume jewellery. However, the mechanism for its formation has been a source of controversy for 75 years and is still not settled. Possible mechanisms proposed include slow sedimentation with regular addition of hydrated iron oxides, leaching of a reddish mudstone, post-depositional mobilisation and subsequent rhythmic precipitation of iron oxides from groundwaters, and accumulation of iron-containing minerals in ripple troughs. Loughnan and Roberts suggested a more detailed explanation and from a detailed mineralogical examination, including XRD, XRF, SEM and TEM, they concluded that the only major difference between the two coloured bands was the presence of hematite, α-Fe 2 O 3 . In an attempt to throw more light on the problem, we have taken 57 Fe Moessbauer spectra of samples from the two different coloured regions. As expected, the white coloured material contained little iron, giving a weak, broad single line spectrum at room temperature. At 78 K, the spectrum has split into a magnetic sextet which has not yet been positively identified. As expected from the XRD, the spectrum of the red part principally consists of a strong sextet due to hematite, although there is also a weak component from the phase in the white material. It is hoped that further analysis will help us to eliminate at least some of the proposed mechanisms for the formation of zebra rock

  4. Potato psyllid vector of zebra chip disease in Pacific Northwest

    Science.gov (United States)

    Zebra chip is a destructive disease of potatoes in the Pacific Northwest and other potato production regions of North America. The pathogen associated with this disease is transmitted by the potato psyllid. A team of researchers which included a scientist at the ARS in Wapato, WA updated an extens...

  5. Variability of IN measured with the Fast Ice Nucleus Chamber (FINCH) at the high altitude research station Jungfraujoch during wintertime 2013

    Science.gov (United States)

    Frank, Fabian; Nillius, Björn; Bundke, Ulrich; Curtius, Joachim

    2014-05-01

    Ice nuclei (IN) are an important component of the atmospheric aerosol. Despite their low concentrations in the atmosphere, they have an influence on the formation of ice crystals in mixed-phase clouds and therefore on precipitation. The Fast Ice Nucleus CHamber (FINCH)1, a counter for ice nucleating particles developed at the Goethe University Frankfurt am Main allows long-term measurements of the IN number concentration. In FINCH the ice activation of the aerosol particles is achieved by mixing air flows with different temperature and humidity. The IN number concentration measurements at different meteorological conditions during the INUIT-JFJ campaign at the high altitude research station Jungfraujoch in Switzerland are presented and its variability are discussed. The good operational performance of the instrument allowed up to 10 hours of continuous measurements. Acknowledgment: This work was supported by the German Research Foundation, DFG Grant: BU 1432/3-2 BU 1432/4-1 in the framework of INUIT (FOR 1525) and SPP 1294 HALO. 1- Bundke, U., Nillius, B., Jaenicke, R., Wetter, T., Klein, H., and Bingemer, H. (2008). The fast ice nucleus chamber finch. Atmospheric Research, 90:180-186.

  6. Local monitoring program for invasion of zebra mussel (Dreissena polymorpha) in the Dam lake Zhrebchevo, Bulgaria

    OpenAIRE

    Stoyanova, Stefka; Nikolov, Galin; Velichkova, Katya; Atanasoff, Alexander; Mumun, Sevdegul

    2015-01-01

    Zebra mussels (Dreissena polymorpha) are bivalve mollusks approximately 1 to 5 cm long that live in freshwater lakes. They have invaded many Bulgarian freshwater ecosystems in recent decades. Because of their ability to settle on almost any substrate, zebra mussels cause severe damage to closed water systems, RAS and intensive fish farming systems. In order to assess the status of the mussel population in the lake in the area of the Forest group fish farm, the distribution, extent of coloniza...

  7. Zebra Alphaherpesviruses (EHV-1 and EHV-9: Genetic Diversity, Latency and Co-Infections

    Directory of Open Access Journals (Sweden)

    Azza Abdelgawad

    2016-09-01

    Full Text Available Alphaherpesviruses are highly prevalent in equine populations and co-infections with more than one of these viruses’ strains frequently diagnosed. Lytic replication and latency with subsequent reactivation, along with new episodes of disease, can be influenced by genetic diversity generated by spontaneous mutation and recombination. Latency enhances virus survival by providing an epidemiological strategy for long-term maintenance of divergent strains in animal populations. The alphaherpesviruses equine herpesvirus 1 (EHV-1 and 9 (EHV-9 have recently been shown to cross species barriers, including a recombinant EHV-1 observed in fatal infections of a polar bear and Asian rhinoceros. Little is known about the latency and genetic diversity of EHV-1 and EHV-9, especially among zoo and wild equids. Here, we report evidence of limited genetic diversity in EHV-9 in zebras, whereas there is substantial genetic variability in EHV-1. We demonstrate that zebras can be lytically and latently infected with both viruses concurrently. Such a co-occurrence of infection in zebras suggests that even relatively slow-evolving viruses such as equine herpesviruses have the potential to diversify rapidly by recombination. This has potential consequences for the diagnosis of these viruses and their management in wild and captive equid populations.

  8. Ammonium detection by formation of colored zebra-bands in a detecting tube.

    Science.gov (United States)

    Hori, Tatsuaki; Niki, Keizou; Kiso, Yoshiaki; Oguchi, Tatsuo; Kamimoto, Yuki; Yamada, Toshiro; Nagai, Masahiro

    2010-06-15

    Ammonium ion was colorized by means of a diazo coupling reaction with 2-phenylphenol, where the color development reaction was conducted within 3min by using boric acid as a catalyst. The resulting colored solution (0.5ml) was supplied by suction to a detecting tube consisting of a nonwoven fabric test strip (2mm wide, 1mm thick, 150mm long) impregnated with benzylcetyldimethylammonium chloride in a stripe pattern and enclosed in a heat-shrinkable tube. When the colored solution was supplied to the detecting tube, blue zebra-bands formed, and the ammonium concentration was determined by counting the number of zebra-bands. The detection range was 1-20mg-Nl(-1). Ammonium ion in actual domestic wastewater samples was successfully detected by means of this method.

  9. Inter- and intra-specific differences in serum proteins of different species and subspecies of zebras.

    Science.gov (United States)

    Stratil, A; Cízová, D; Gábrisová, E; Pokorný, R

    1992-11-01

    1. Serum proteins of Equus grevyi, E. zebra hartmannae, E. burchelli boehmi, E. b. chapmanni and E. b. antiquorum were studied using starch-gel electrophoresis, 1-D polyacrylamide-gel electrophoresis, inhibitions of trypsin and chymotrypsin, immunoblotting, and specific staining for esterase. 2. Clear species-specific patterns were observed in albumin, transferrin, and for E. grevyi in protease inhibitor-1. Specific esterase was detected only in E. z. hartmannae. 3. Protein polymorphism was found in all studied species: E. grevyi--transferrin; E. z. hartmannae--protease inhibitor-1; E. b. boehmi--albumin, GC, transferrin, protease inhibitor-1, protease inhibitor-T; E. b. chapmanni--albumin, GC, transferrin, protease inhibitor-1; E. b. antiquorum--GC, transferrin, protease inhibitor-1. 4. Phenotype patterns of the polymorphic proteins were indicative of simple codominant inheritance. Further studies of polymorphism of protease inhibitor-2 and variability of protease inhibitor-X are needed. 5. alpha 1B glycoprotein in all zebra species was monomorphic. 6. The main transferrin components and alpha 1B glycoprotein of zebra (E. b. boehmi) were characterized for terminal sialic acid content.

  10. FindZebra - using machine learning to aid diagnosis of rare diseases

    DEFF Research Database (Denmark)

    Svenstrup, Dan Tito

    FindZebra is a search engine for rare diseases intended to act as a diagnosis decision support system (DDSS) capable of assisting the user both during and after a search. Rare diseases are diseases that affect only a small part of the population (less than one in two thousand). Currently around...... retrieval systems. Improving retrieval performance is important, but is not the only way of improving the success rate of a DDSS such as FindZebra. Following an unsuccessful search, the search engine should assist the user by indicating what information is likely to be missing. This idea is called...... language and the search engine should then give a suggestion for a differential diagnosis based on all the information contained in a multilingual corpus, not only in the native corpus. Methods for performing multilingual search will be the fourth line of research explored in this dissertation. ...

  11. Reproductive behavior of the Red-crested Finch Coryphospingus cucullatus (Aves: Thraupidae in southeastern Brazil

    Directory of Open Access Journals (Sweden)

    Paulo V.Q. Zima

    Full Text Available ABSTRACT Several behavioral aspects of the Red-crested Finch Coryphospingus cucullatus (Statius Müller, 1776 are poorly studied. Here we provide reproductive information on 16 active nests. This information may be valuable to elucidate the phylogenetic relationships of this bird, and to design plans to manage it. Nesting activities occurred from October to February. Clutches consisted of two to three eggs (2.06 ± 0.25, which were laid on consecutive days. Incubation usually started the morning the females laid their last egg and lasted 11.27 ± 0.47 days. Hatching was synchronous, or happened at a one-day interval. The nestling stage lasted 12 ± 0.89 days. Only females incubated the eggs and they fed the young more often than the males did. Overall nesting success, from incubation to fledging, was 28.2%. Nest architecture and egg color proved to be diagnostic characteristics of Coryphospingus , supporting its maintenance as a distinct genus within the recently proposed sub-family Tachyphoninae. Red-crested Finches showed a preference for certain nesting sites, i.e., forest borders or a Cerrado in late regeneration stage. This information can be useful to programs aiming to release illegally trapped individuals.

  12. Mutations of amino acids in the DNA-recognition domain of Epstein-Barr virus ZEBRA protein alter its sub-nuclear localization and affect formation of replication compartments

    International Nuclear Information System (INIS)

    Park, Richard; Heston, Lee; Shedd, Duane; Delecluse, Henri-Jacques; Miller, George

    2008-01-01

    ZEBRA, a transcription factor and DNA replication protein encoded by the Epstein-Barr virus (EBV) BZLF1 gene, plays indispensable roles in the EBV lytic cycle. We recently described the phenotypes of 46 single amino acid substitutions introduced into the DNA-recognition region of ZEBRA [Heston, L., El-Guindy, A., Countryman, J., Dela Cruz, C., Delecluse, H.J., and Miller, G. 2006]. The 27 DNA-binding-proficient mutants exhibited distinct defects in their ability to activate expression of the kinetic classes of viral genes. Four phenotypic variants could be discerned: wild-type, defective at activating Rta, defective at activating early genes, and defective at activating late genes. Here we analyze the distribution of ZEBRA within the nucleus and the localization of EA-D (the viral DNA polymerase processivity factor), an indicator of the development of replication compartments, in representatives of each phenotypic group. Plasmids encoding wild-type (WT) and mutant ZEBRA were transfected into 293 cells containing EBV-bacmids. WT ZEBRA protein was diffusely and smoothly distributed throughout the nucleus, sparing nucleoli, and partially recruited to globular replication compartments. EA-D induced by WT ZEBRA was present diffusely in some cells and concentrated in globular replication compartments in other cells. The distribution of ZEBRA and EA-D proteins was identical to WT following transfection of K188R, a mutant with a conservative change. The distribution of S186A mutant ZEBRA protein, defective for activation of Rta and EA-D, was identical to WT, except that the mutant ZEBRA was never found in globular compartments. Co-expression of Rta with S186A mutant rescued diffuse EA-D but not globular replication compartments. The most striking observation was that several mutant ZEBRA proteins defective in activating EA-D (R179A, K181A and A185V) and defective in activating lytic viral DNA replication and late genes (Y180E and K188A) were localized to numerous punctate

  13. Birth of projection neurons in adult avian brain may be related to perceptual or motor learning

    International Nuclear Information System (INIS)

    Alvarez-Buylla, A.; Kirn, J.R.; Nottebohm, F.

    1990-01-01

    Projection neurons that form part of the motor pathway for song control continue to be produced and to replace older projection neurons in adult canaries and zebra finches. This is shown by combining [3H]thymidine, a cell birth marker, and fluorogold, a retrogradely transported tracer of neuronal connectivity. Species and seasonal comparisons suggest that this process is related to the acquisition of perceptual or motor memories. The ability of an adult brain to produce and replace projection neurons should influence our thinking on brain repair

  14. Simple Approaches to Improve the Automatic Inventory of ZEBRA Crossing from Mls Data

    Science.gov (United States)

    Arias, P.; Riveiro, B.; Soilán, M.; Díaz-Vilariño, L.; Martínez-Sánchez, J.

    2015-08-01

    The city management is increasingly supported by information technologies, leading to paradigms such as smart cities, where decision-makers, companies and citizens are continuously interconnected. 3D modelling turns of great relevance when the city has to be managed making use of geospatial databases or Geographic Information Systems. On the other hand, laser scanning technology has experienced a significant growth in the last years, and particularly, terrestrial mobile laser scanning platforms are being more and more used with inventory purposes in both cities and road environments. Consequently, large datasets are available to produce the geometric basis for the city model; however, this data is not directly exploitable by management systems constraining the implementation of the technology for such applications. This paper presents a new algorithm for the automatic detection of zebra crossing. The algorithm is divided in three main steps: road segmentation (based on a PCA analysis of the points contained in each cycle of collected by a mobile laser system), rasterization (conversion of the point cloud to a raster image coloured as a function of intensity data), and zebra crossing detection (using the Hough Transform and logical constrains for line classification). After evaluating different datasets collected in three cities located in Northwest Spain (comprising 25 strips with 30 visible zebra crossings) a completeness of 83% was achieved.

  15. Adding injury to infection: The relationship between injury status and genetic diversity of Theileria infecting plains zebra, Equus quagga.

    Science.gov (United States)

    King'ori, Edward M; Obanda, Vincent; Ndambiri, Ephantus M; Runo, Steven M; Chiyo, Patrick I

    2018-03-01

    Asymptomatic tick-borne infections are a common feature in wild herbivores. In human-dominated habitats, snare injuries to wild herbivores are common and are likely to co-occur with enzootic infections. The influence of injury on pattern, course and outcome of enzootic infection in wild herbivores is unknown. We identified Theileria species infecting zebra and assessed the relationship between host injury-status and parasitaemia, parasite diversity and selection regimes. We also determined host leucocyte differential as this can reveal mechanisms by which injuries influence infections. Theileria infecting zebra was identified using PCR and sequencing of the V4 region of the 18 s rRNA gene and confirmed with phylogenetic analyses. The influence of injury status on parasite infection patterns, genetic diversity and selection were assessed using population genetic tools. Parasitaemia estimated from prevalence and leucocyte differential were determined from microscopic examination of Giemsa stained thin blood smears. Phylogenetic and sequence analyses revealed that the zebra population studied was infected with three Theileria equi haplotypes. Parasitaemia was lower among injured compared to non-injured animals and lower during dry than wet season. Mean (±SD) genetic diversity was 0.386 (±0.128) in injured and 0.513 (±0.144) in non-injured zebra (P = .549). Neutrality tests indicated that T. equi is under strong purifying selection in injured females (Li & Fu's D* = -2.037) and demographic expansion in all zebra during the wet season (Tajima D = -1.904). Injured zebras had a higher median per cent of neutrophils (64% vs 37%) a lower median per cent of basophils (0% vs 1%) and eosinophils (2% vs 4.5%) than non-injured animals, suggesting a heightened immune response and a shift from a Th2 to Th1 T-Cell response favoring the elimination of intracellular parasites in injured animals. This study demonstrates the utility of population genetics in revealing

  16. Comparison of learning ability and memory retention in altricial (Bengalese finch, Lonchura striata var. domestica) and precocial (blue-breasted quail, Coturnix chinensis) birds using a color discrimination task.

    Science.gov (United States)

    Ueno, Aki; Suzuki, Kaoru

    2014-02-01

    The present study sought to assess the potential application of avian models with different developmental modes to studies on cognition and neuroscience. Six altricial Bengalese finches (Lonchura striata var. domestica), and eight precocial blue-breasted quails (Coturnix chinensis) were presented with color discrimination tasks to compare their respective faculties for learning and memory retention within the context of the two developmental modes. Tasks consisted of presenting birds with discriminative cues in the form of colored feeder lids, and birds were considered to have learned a task when 80% of their attempts at selecting the correctly colored lid in two consecutive blocks of 10 trials were successful. All of the finches successfully performed the required experimental tasks, whereas only half of the quails were able to execute the same tasks. In the learning test, finches required significantly fewer trials than quails to learn the task (finches: 13.5 ± 9.14 trials, quails: 45.8 ± 4.35 trials, P memory retention tests, which were conducted 45 days after the learning test, finches retained the ability to discriminate between colors correctly (95.0 ± 4.47%), whereas quails did not retain any memory of the experimental procedure and so could not be tested. These results suggested that altricial and precocial birds both possess the faculty for learning and retaining discrimination-type tasks, but that altricial birds perform better than precocial birds in both faculties. The present findings imply that developmental mode is an important consideration for assessing the suitability of bird species for particular experiments. © 2013 Japanese Society of Animal Science.

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

    Science.gov (United States)

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

  18. Host social rank and parasites: plains zebra (Equus quagga) and intestinal helminths in Uganda.

    Science.gov (United States)

    Fugazzola, M C; Stancampiano, L

    2012-08-13

    The main aim of this study was to evaluate the relationship between the social hierarchy of plain zebra, Equus quagga, and the level of parasitism. For the study 141 fecal samples from the same number of animals were collected within the two major populations of E. quagga of Uganda (Lake Mburo Conservation Area and Kidepo Valley National Park). Quantitative (eggs per gram of feces) and qualitative parasite assessment were performed with standard methods. The relationship between parasite burden and individual host features was analyzed using Generalized Linear Models. Strongyles, cestodes, Strongyloides sp. and oxiurids where present in the examined samples. Social rank and age class significantly affect all parasites' abundance with dominant individuals being less parasitized than subordinate individuals, regardless of the parasite groups excluding oxiurids. Sex could not been shown to be related with any of the found parasites. Age was positively related with strongyles and oxiurids abundance and negatively related with cestodes and Strongyloides sp. The main result of the present study was the evidence that social status influences parasite level with dominant zebras shedding less parasite eggs than subordinate ones. Social rank appears, therefore, as an important factor giving rise to parasite aggregation in plain zebras. Copyright © 2012 Elsevier B.V. All rights reserved.

  19. Great Lakes clams find refuge from zebra mussels in restored, lake-connected marsh (Ohio)

    Science.gov (United States)

    Nichols, S. Jerrine; Wilcox, Douglas A.

    2004-01-01

    Since the early 1990s, more than 95 percent of the freshwater clams once found in Lake Erie have died due to the exotic zebara mussel (Dreissena polymorpha). Zebra mussels attach themselves to native clams in large numbers, impeding the ability of the clams to eat and burrow. However, in 1996, we discovered a population of native clams in Metzger Marsh in western Lake Erie (about 50 miles [80 km] east of Toledo) that were thriving despite the longtime presence of zebra mussel in surrounding waters. At that time, Metzger Marsh was undergoing extensive restoration, including construction of a dike to replace the eroded barrier beach and of a water-control structure to maintain hydrologic connections with the lake (Wilcox and Whillans 1999). The restoration plan called for a drawdown of water levels to promote plant growth from the seedbank -- a process that would also destroy most of the clam population. State and federal resource managers recommended removing as many clams as possible to a site that was isolated from zebra mussels, and then returning them to the marsh after it was restored. We removed about 7,000 native clams in 1996 and moved them back to Metzger Marsh in 1999.

  20. Use of alternating and pulsed direct current electrified fields for zebra mussel control

    Science.gov (United States)

    Luoma, James A.; Dean, Jan C.; Severson, Todd J.; Wise, Jeremy K.; Barbour, Matthew

    2017-01-01

    Alternatives to chemicals for controlling dreissenid mussels are desirable for environmental compatibility, but few alternatives exist. Previous studies have evaluated the use of electrified fields for stunning and/or killing planktonic life stages of dreissenid mussels, however, the available literature on the use of electrified fields to control adult dreissenid mussels is limited. We evaluated the effects of sinusoidal alternating current (AC) and 20% duty cycle square-wave pulsed direct current (PDC) exposure on the survival of adult zebra mussels at water temperatures of 10, 15, and 22 °C. Peak voltage gradients of ~ 17 and 30 Vp/cm in the AC and PDC exposures, respectively, were continuously applied for 24, 48, or 72 h. Peak power densities ranged from 77,999 to 107,199 µW/cm3 in the AC exposures and 245,320 to 313,945 µW/cm3 in the PDC exposures. The peak dose ranged from 6,739 to 27,298 Joules/cm3 and 21,306 to 80,941 Joules/cm3 in the AC and PDC exposures, respectively. The applied power ranged from 16.6 to 68.9 kWh in the AC exposures and from 22.2 to 86.4 kWh in the PDC exposures. Mortality ranged from 2.7 to 92.7% in the AC exposed groups and from 24.0 to 98.7% in PDC exposed groups. Mortality increased with corresponding increases in water temperature and exposure duration, and we observed more zebra mussel mortality in the PDC exposures. Exposures conducted with AC required less of a peak dose (Joules/cm3) but more applied power (kWh) to achieve the same level of adult zebra mussel mortality as corresponding PDC exposures. The results demonstrate that 20% duty cycle square-wave PDC requires less energy than sinusoidal AC to inducing the same level of adult zebra mussel mortality.

  1. Stress Responses to Heat Exposure in Three Species of Australian Desert Birds.

    Science.gov (United States)

    Xie, Shangzhe; Romero, L Michael; Htut, Zaw Win; McWhorter, Todd J

    Birds need to respond to weather changes quickly and appropriately for their own well-being and survival. The inability to respond appropriately to heat waves can be fatal to individual birds and can translate into large-scale mortality events. We investigated corticosterone (CORT) and heterophil∶lymphocyte (H∶L) ratio responses of budgerigars (Melopsittacus undulatus), zebra finches (Taeniopygia guttata), and diamond doves (Geopelia cuneata) to heat exposures. The birds were exposed to a temperature similar to what they experience during a typical summer day (35°C) and a higher temperature (45°C) similar to that experienced during a heat wave. There were no significant increases between the CORT concentrations before and after heat exposure in zebra finches and budgerigars at 35° and 45°C, but there was a significant increase in CORT concentrations in diamond doves after exposure to 45°C. The H∶L ratios increased significantly after heat exposure in budgerigars at 35° and 45°C and in diamond doves at 35°C. No significant correlation was found between the changes in CORT and H∶L ratios. The data suggest that there are species differences in birds' stress responses to heat exposure that may reflect their ability to detect and adapt to high temperatures. There appear to be differences between the two types of stress measurements, which may reflect differences in the timescales of these responses.

  2. Inhibition of hippocampal aromatization impairs spatial memory performance in a male songbird.

    Science.gov (United States)

    Bailey, David J; Ma, Chunqi; Soma, Kiran K; Saldanha, Colin J

    2013-12-01

    Recent studies have revealed the presence and regulation of aromatase at the vertebrate synapse, and identified a critical role played by presynaptic estradiol synthesis in the electrophysiological response to auditory and other social cues. However, if and how synaptic aromatization affects behavior remains to be directly tested. We have exploited 3 characteristics of the zebra finch hippocampus (HP) to test the role of synaptocrine estradiol provision on spatial memory function. Although the zebra finch HP contains abundant aromatase transcripts and enzyme activity, immunocytochemical studies reveal widespread pre- and postsynaptic, but sparse to undetectable somal, localization of this enzyme. Further, the superficial location of the avian HP makes possible the more exclusive manipulation of its neurochemical characteristics without perturbation of the neuropil and the resultant induction of astroglial aromatase. Last, as in other vertebrates, the HP is critical for spatial memory performance in this species. Here we report that local inhibition of hippocampal aromatization impairs spatial memory performance in an ecologically valid food-finding task. Local aromatase inhibition also resulted in lower levels of estradiol in the HP, but not in adjacent brain areas, and was achieved without the induction of astroglial aromatase. The observed decrement in acquisition and subsequent memory performance as a consequence of lowered aromatization was similar to that achieved by lesioning this locus. Thus, hippocampal aromatization, much of which is achieved at the synapse in this species, is critical for spatial memory performance.

  3. A draft de novo genome assembly for the northern bobwhite (Colinus virginianus reveals evidence for a rapid decline in effective population size beginning in the Late Pleistocene.

    Directory of Open Access Journals (Sweden)

    Yvette A Halley

    Full Text Available Wild populations of northern bobwhites (Colinus virginianus; hereafter bobwhite have declined across nearly all of their U.S. range, and despite their importance as an experimental wildlife model for ecotoxicology studies, no bobwhite draft genome assembly currently exists. Herein, we present a bobwhite draft de novo genome assembly with annotation, comparative analyses including genome-wide analyses of divergence with the chicken (Gallus gallus and zebra finch (Taeniopygia guttata genomes, and coalescent modeling to reconstruct the demographic history of the bobwhite for comparison to other birds currently in decline (i.e., scarlet macaw; Ara macao. More than 90% of the assembled bobwhite genome was captured within 14,000 unique genes and proteins. Bobwhite analyses of divergence with the chicken and zebra finch genomes revealed many extremely conserved gene sequences, and evidence for lineage-specific divergence of noncoding regions. Coalescent models for reconstructing the demographic history of the bobwhite and the scarlet macaw provided evidence for population bottlenecks which were temporally coincident with human colonization of the New World, the late Pleistocene collapse of the megafauna, and the last glacial maximum. Demographic trends predicted for the bobwhite and the scarlet macaw also were concordant with how opposing natural selection strategies (i.e., skewness in the r-/K-selection continuum would be expected to shape genome diversity and the effective population sizes in these species, which is directly relevant to future conservation efforts.

  4. Early responses to zebra mussels in the Great Lakes: a journey from information vacuum to policy and regulation

    Science.gov (United States)

    Griffiths, Ronald W.; Schloesser, Don W.; Kovalak, William P.

    2013-01-01

    Invasive species such as zebra mussels pose a threat to the economies and environments of coastal and fresh-water habitats around the world. Consequently, it is important that government policies and programs be adequate to protect these waters from invaders. This chapter documents key events that took place in the early years (1988-1991) of zebra mussel colonization of the Laurentian Great Lakes and evaluates government responses (policies and programs) to this disruptive, invasive, freshwater species.

  5. Experimental demonstration of a parasite-induced immune response in wild birds: Darwin's finches and introduced nest flies.

    Science.gov (United States)

    Koop, Jennifer A H; Owen, Jeb P; Knutie, Sarah A; Aguilar, Maria A; Clayton, Dale H

    2013-08-01

    Ecological immunology aims to explain variation among hosts in the strength and efficacy of immunological defenses. However, a shortcoming has been the failure to link host immune responses to actual parasites under natural conditions. Here, we present one of the first experimental demonstrations of a parasite-induced immune response in a wild bird population. The recently introduced ectoparasitic nest fly Philornis downsi severely impacts the fitness of Darwin's finches and other land birds in the Galápagos Islands. An earlier study showed that female medium ground finches (Geospiza fortis) had P. downsi-binding antibodies correlating with presumed variation in fly exposure over time. In the current study, we experimentally manipulated fly abundance to test whether the fly does, in fact, cause changes in antibody levels. We manipulated P. downsi abundance in nests and quantified P. downsi-binding antibody levels of medium ground finch mothers, fathers, and nestlings. We also quantified host behaviors, such as preening, which can integrate with antibody-mediated defenses against ectoparasites. Philornis downsi-binding antibody levels were significantly higher among mothers at parasitized nests, compared to mothers at (fumigated) nonparasitized nests. Mothers with higher antibody levels tended to have fewer parasites in their nests, suggesting that antibodies play a role in defense against parasites. Mothers showed no behavioral changes that would enhance the effectiveness of the immune response. Neither adult males, nor nestlings, had P. downsi-induced immunological or behavioral responses that would enhance defense against flies. None of the parasitized nests fledged any offspring, despite the immune response by mothers. Thus, this study shows that, while the immune response of mothers appeared to be defensive, it was not sufficient to rescue current reproductive fitness. This study further shows the importance of testing the fitness consequences of immune

  6. Making the Best of a Pest: The Potential for Using Invasive Zebra Mussel ( Dreissena Polymorpha) Biomass as a Supplement to Commercial Chicken Feed

    Science.gov (United States)

    McLaughlan, Claire; Rose, Paul; Aldridge, David C.

    2014-11-01

    Invasive non-native species frequently occur in very high densities. When such invaders present an economic or ecological nuisance, this biomass is typically removed and landfill is the most common destination, which is undesirable from both an economic and ecological perspective. The zebra mussel, Dreissena polymorpha, has invaded large parts of Europe and North America, and is routinely removed from raw water systems where it creates a biofouling nuisance. We investigated the suitability of dried, whole zebra mussels as a supplement to poultry feed, thus providing a more attractive end-use than disposal to landfill. Measurable outcomes were nutrient and energy composition analyses of the feeds and production parameters of the birds over a 14 day period. Zebra mussels were a palatable feed supplement for chickens. The mussel meal contained high levels of calcium (344.9 g kg-1), essential for egg shell formation, which was absorbed and retained easily by the birds. Compared with standard feed, a mussel-supplemented diet caused no significant effects on production parameters such as egg weight and feed conversion ratio during the study period. However, protein and energy levels in the zebra mussel feed were much lower than expected from the literature. In order for zebra mussels to be a viable long-term feed supplement for poultry, flesh would need to be separated from the shells in an economically viable way. If zebra mussels were to be used with the shells remaining, it seems that the resultant mussel meal would be more suitable as a calcium supplement.

  7. Environmentally Safe Control of Zebra Mussel Fouling

    Energy Technology Data Exchange (ETDEWEB)

    Daniel Molloy

    2008-02-29

    The two primary objectives of this USDOE-NETL contract were successfully achieved during the project: (1) to accelerate research on the development of the bacterium Pseudomonas fluorescens strain CL145A (Pf-CL145A) as a biocontrol agent for zebra mussels (Dreissena polymorpha) and quagga mussels (Dreissena rostriformis bugensis)--two invasive freshwater bivalve species that are infesting water pipes in power plants; and (2) to identify a private-sector company that would move forward to commercialize Pf-CL145A as a substitute for the current polluting use of biocide chemicals for control of these dreissenid mussels in power plant pipes.

  8. Zebra: An advanced PWR lattice code

    Energy Technology Data Exchange (ETDEWEB)

    Cao, L.; Wu, H.; Zheng, Y. [School of Nuclear Science and Technology, Xi' an Jiaotong Univ., No. 28, Xianning West Road, Xi' an, ShannXi, 710049 (China)

    2012-07-01

    This paper presents an overview of an advanced PWR lattice code ZEBRA developed at NECP laboratory in Xi'an Jiaotong Univ.. The multi-group cross-section library is generated from the ENDF/B-VII library by NJOY and the 361-group SHEM structure is employed. The resonance calculation module is developed based on sub-group method. The transport solver is Auto-MOC code, which is a self-developed code based on the Method of Characteristic and the customization of AutoCAD software. The whole code is well organized in a modular software structure. Some numerical results during the validation of the code demonstrate that this code has a good precision and a high efficiency. (authors)

  9. Zebra: An advanced PWR lattice code

    International Nuclear Information System (INIS)

    Cao, L.; Wu, H.; Zheng, Y.

    2012-01-01

    This paper presents an overview of an advanced PWR lattice code ZEBRA developed at NECP laboratory in Xi'an Jiaotong Univ.. The multi-group cross-section library is generated from the ENDF/B-VII library by NJOY and the 361-group SHEM structure is employed. The resonance calculation module is developed based on sub-group method. The transport solver is Auto-MOC code, which is a self-developed code based on the Method of Characteristic and the customization of AutoCAD software. The whole code is well organized in a modular software structure. Some numerical results during the validation of the code demonstrate that this code has a good precision and a high efficiency. (authors)

  10. THE USE OF COST-TRANSFER ANALYSIS TO ESTIMATE THE ECONOMIC IMPACTS OF A POTENTIAL ZEBRA MUSSEL INFESTATION IN FLORIDA

    OpenAIRE

    Rossi, Frederick J.; Adams, Damian C.; Lee, Donna J.

    2004-01-01

    Zebra mussel (Dreissena polymorpha) colonization of the eastern United States has resulted in expenditures of tens of millions of dollars spent by consumptive surface water users, in order to mitigate infrastructure impairment caused by this invasive species. Analogous to benefit-transfer analysis, a "cost-transfer" approach will be used to obtain general estimates of potential mitigation costs of zebra mussels in an area (Florida) that this invasive species has yet to establish itself. The g...

  11. Physiological response to chemical immobilization: a case study of etorphine-azaperone in free-ranging plains zebra (Equus quagga in Kenya

    Directory of Open Access Journals (Sweden)

    Francesca Vitali

    2018-06-01

    Full Text Available Predictable immobilization of wild zebras is challenging and there is massive variation in opiate response within different species. Etorphine combined with azaperone is considered the protocol of choice, but no studies have investigated the physiological response to this procedure of immobilization in plains zebras.   Eleven free-ranging plains zebras (Equus quagga were immobilized in Kenya using a combination of etorphine 0.019 ± 0.003 mg/kg and azaperone 0.27 ± 0.05 mg/kg administered intramuscularly with a projectile dart. After recumbency, an arterial sample was performed for blood gas analysis and physiological parameters were recorded every five minutes. Descriptive scores were given to the exertion resulting from high-speed chasing and to the quality of induction, immobilization and recovery. Diprenorphine or naltrexone were used for opioid antagonism.   In all zebras, the combination induced quick inductions within 3.5 ± 0.8 minutes and provided reliable recumbencies without attempts to stand for the entire duration of the immobilization. The average heart rates, respiratory rates and mean arterial blood pressure recorded were 102 ± 42 beats/minute, 18 ± 4 breaths/minute and 145 ± 28 mmHg respectively. Arterial gas analyses demonstrated mild to severe and partially compensated metabolic acidosis and hypoxia, while electrolytes were within equids range. In particular, higher exertion levels during the chasing were significantly correlated to worse immobilization scores (p=0.008 and hyperthermia occurrence (p=0.0012 and non-significantly to more severe acidosis. Recoveries from anaesthesia were smooth, on average 121 ± 38 seconds after diprenorphine/naltrexone administration.             Etorphine-azaperone combination produced physiological alterations in free-ranging plains zebra such as tachycardia, hypertension, metabolic acidosis and hypoxemia. However, these preliminary results indicate that high-speed chase

  12. Influence of ortho-substitution homolog group on polychlorobiphenyl bioaccumulation factors and fugacity ratios in plankton and zebra mussels (Dreissena polymorpha)

    Energy Technology Data Exchange (ETDEWEB)

    Willman, E.J.; Manchester-Neesvig, J.B.; Agrell, C.; Armstrong, D.E.

    1999-07-01

    The accumulation of a set of non- and mono-ortho (coplanar) PCB congeners in aquatic ecosystems is of interest due to their dioxin-like toxicities. Chemical properties (octanol-water partition coefficients) suggest that the coplanar congeners may accumulate in organisms to a greater extent than homologs with greater ortho substitution. The authors analyzed a set of 65 PCB congeners with zero to four ortho-chlorines from seven homolog groups in water, suspended particulate matter, and zebra mussels from Green Bay, Wisconsin, USA, on four dates throughout the ice-free season. The suspended particulate matter was separated by size and characterized as phytoplankton or zooplankton using diagnostic carotenoid pigments and light microscopy. Median bioconcentration factors (BCFs) for accumulation from water by phytoplankton and bioaccumulation factors (BAFs) for accumulation from water plus food by zooplankton and zebra mussels ranged from 1 x 10{sup 4} to 1 x 10{sup 6} and were generally the greatest for the tetra- to heptachlorobiphenyls. The average coplanar congener BCFs and BAFs for accumulation from water by phytoplankton, zooplankton, and zebra mussels for the tri-, tetra-, and pentachlorobiphenyls were 54% larger than corresponding values for their homologs. Biomagnification factors (BMFs) of the tetra-, penta-, and hexachlorobiphenyls between zooplankton and zebra mussels and their food source, phytoplankton, typically ranged between 1 and 10, but the average coplanar congener BMFs were 25% less than values for their corresponding homologs. The tendency for coplanar congeners to accumulate to a lesser extent between trophic levels was not as large as their tendency to accumulate from water to a greater extent. Based on accumulation factors, the authors conclude that the dioxin-like tetra- and pentachlorobiphenyls generally accumulate in the phytoplankton, zooplankton, and zebra mussels of the Green Bay ecosystem to a greater extent than other congeners. Fugacity

  13. Prevalence of Theileria equi and Babesia caballi as well as the identification of associated ticks in sympatric Grevy's zebras (Equus grevyi) and donkeys (Equus africanus asinus) in northern Kenya.

    Science.gov (United States)

    Hawkins, Elaine; Kock, Richard; McKeever, Declan; Gakuya, Francis; Musyoki, Charles; Chege, Stephen M; Mutinda, Mathew; Kariuki, Edward; Davidson, Zeke; Low, Belinda; Skilton, Robert A; Njahira, Moses N; Wamalwa, Mark; Maina, Elsie

    2015-01-01

    The role of equine piroplasmosis as a factor in the population decline of the Grevy's zebra is not known. We determined the prevalence of Babesia caballi and Theileria equi in cograzing Grevy's zebras (Equus grevyi) and donkeys (Equus africanus asinus) in northern Kenya and identified the associated tick vectors. Blood samples were taken from 71 donkeys and 16 Grevy's zebras from March to May 2011. A nested PCR reaction using 18s ribosomal (r)RNA primers on 87 blood spots showed 72% (51/71; 95% confidence interval [CI] 60.4-81.0%) of donkeys and 100% (16/16; 95% CI, 77.3-100%) of Grevy's zebras were T. equi positive. No samples were positive for B. caballi. Sequence comparison using the National Center for Biotechnology Information's basic local alignment search tool identified homologous 18s rRNA sequences with a global geographic spread. The T. equi-derived sequences were evaluated using Bayesian approaches with independent Metropolis-coupled Markov chain Monte Carlo runs. The sequences clustered with those found in Sudan, Croatia, Mongolia, and the US, with statistical support greater than 80% for the two main clades. Hyalomma tick species were found on both donkeys and Grevy's zebras, whereas Rhipicephalus pulchellus was found exclusively on Grevy's zebras and Hyalomma marginatum rupfipes on donkeys. The prevalence of T. equi was 100% in Grevy's zebras and 72% in donkeys with common tick vectors identified. Our results suggest that donkeys and Grevy's zebras can be asymptomatic carriers and that piroplasmosis is endemic in the study area.

  14. A southern African origin and cryptic structure in the highly mobile plains zebra

    DEFF Research Database (Denmark)

    Pedersen, Casper-Emil T; Albrechtsen, Anders; Etter, Paul D.

    2018-01-01

    insights into the past phylogeography of the species. The results identify a southern African location as the most likely source region from which all extant populations expanded around 370,000 years ago. We show evidence for inclusion of the extinct and phenotypically divergent quagga (Equus quagga quagga......The plains zebra (Equus quagga) is an ecologically important species of the African savannah. It is also one of the most numerous and widely distributed ungulates, and six subspecies have been described based on morphological variation. However, the within-species evolutionary processes have been...... difficult to resolve due to its high mobility and a lack of consensus regarding the population structure. We obtained genome-wide DNA polymorphism data from more than 167,000 loci for 59 plains zebras from across the species range, encompassing all recognized extant subspecies, as well as three mountain...

  15. Zebra - sõbralik ja lillelõhnaline / Ell-Maaja Randküla

    Index Scriptorium Estoniae

    Randküla, Ell-Maaja, 1939-2016

    2006-01-01

    Tallinnas Narva mnt. 7 asuva kohviku Zebra sisekujundus. Sisearhitekt Tiiu Truus. Ehitus: AS KMG Ehitus. Materjalidest on kasutatud triibulise mustriga puitu Zebrano ja looduskivi. Laes on dekoratiivsed lipud, mille graafiline kujundus on Tiiu Priskolt ja Mati Veermetsalt. Tualettruumi looduskivist valamu ja põrandavaasi autor on Kaido Kivi. Ill.: põhiplaan, 11 värv. vaadet

  16. Assimilation and depuration of microcystin–LR by the zebra mussel, Dreissena polymorpha

    NARCIS (Netherlands)

    Pires, L.M.D.; Karlsson, K.M.; Meriluoto, J.A.O.; Kardinaal, E.A.; Visser, P.M.; Siewertsen, K.; Van Donk, E.; Ibelings, B.W.

    2004-01-01

    Zebra mussels (Dreissena polymorpha) are an important component of the foodweb of shallow lakes in the Netherlands, amongst others in Lake IJsselmeer, an international important wetland. Large numbers of ducks feed on these mussels in autumn and winter. The mussels are filter feeders and are exposed

  17. Involvement of apoptosis in host-parasite interactions in the zebra mussel.

    Directory of Open Access Journals (Sweden)

    Laëtitia Minguez

    Full Text Available The question of whether cell death by apoptosis plays a biological function during infection is key to understanding host-parasite interactions. We investigated the involvement of apoptosis in several host-parasite systems, using zebra mussels Dreissena polymorpha as test organisms and their micro- and macroparasites. As a stress response associated with parasitism, heat shock proteins (Hsp can be induced. In this protein family, Hsp70 are known to be apoptosis inhibitors. Mussels were diagnosed for their respective infections by standard histological methods; apoptosis was detected using the TUNEL methods on paraffin sections and Hsp70 by immunohistochemistry on cryosections. Circulating hemocytes were the main cells observed in apoptosis whereas infected tissues displayed no or few apoptotic cells. Parasitism by intracellular bacteria Rickettsiales-like and the trematode Bucephalus polymorphus were associated with the inhibition of apoptosis whereas ciliates Ophryoglena spp. or the trematode Phyllodistomum folium did not involve significant differences in apoptosis. Even if some parasites were able to modulate apoptosis in zebra mussels, we did not see evidence of any involvement of Hsp70 on this mechanism.

  18. Involvement of Apoptosis in Host-Parasite Interactions in the Zebra Mussel

    Science.gov (United States)

    Minguez, Laëtitia; Brulé, Nelly; Sohm, Bénédicte; Devin, Simon; Giambérini, Laure

    2013-01-01

    The question of whether cell death by apoptosis plays a biological function during infection is key to understanding host-parasite interactions. We investigated the involvement of apoptosis in several host-parasite systems, using zebra mussels Dreissena polymorpha as test organisms and their micro- and macroparasites. As a stress response associated with parasitism, heat shock proteins (Hsp) can be induced. In this protein family, Hsp70 are known to be apoptosis inhibitors. Mussels were diagnosed for their respective infections by standard histological methods; apoptosis was detected using the TUNEL methods on paraffin sections and Hsp70 by immunohistochemistry on cryosections. Circulating hemocytes were the main cells observed in apoptosis whereas infected tissues displayed no or few apoptotic cells. Parasitism by intracellular bacteria Rickettsiales-like and the trematode Bucephalus polymorphus were associated with the inhibition of apoptosis whereas ciliates Ophryoglena spp. or the trematode Phyllodistomum folium did not involve significant differences in apoptosis. Even if some parasites were able to modulate apoptosis in zebra mussels, we did not see evidence of any involvement of Hsp70 on this mechanism. PMID:23785455

  19. Biomechanics of predator-prey arms race in lion, zebra, cheetah and impala

    Science.gov (United States)

    Wilson, Alan M.; Hubel, Tatjana Y.; Wilshin, Simon D.; Lowe, John C.; Lorenc, Maja; Dewhirst, Oliver P.; Bartlam-Brooks, Hattie L. A.; Diack, Rebecca; Bennitt, Emily; Golabek, Krystyna A.; Woledge, Roger C.; McNutt, J. Weldon; Curtin, Nancy A.; West, Timothy G.

    2018-02-01

    The fastest and most manoeuvrable terrestrial animals are found in savannah habitats, where predators chase and capture running prey. Hunt outcome and success rate are critical to survival, so both predator and prey should evolve to be faster and/or more manoeuvrable. Here we compare locomotor characteristics in two pursuit predator-prey pairs, lion-zebra and cheetah-impala, in their natural savannah habitat in Botswana. We show that although cheetahs and impalas were universally more athletic than lions and zebras in terms of speed, acceleration and turning, within each predator-prey pair, the predators had 20% higher muscle fibre power than prey, 37% greater acceleration and 72% greater deceleration capacity than their prey. We simulated hunt dynamics with these data and showed that hunts at lower speeds enable prey to use their maximum manoeuvring capacity and favour prey survival, and that the predator needs to be more athletic than its prey to sustain a viable success rate.

  20. ZebraLancer: Private and Anonymous Crowdsourcing System atop Open Blockchain

    OpenAIRE

    Lu, Yuan; Tang, Qiang; Wang, Guiling

    2018-01-01

    We design and implement the first private and anonymous decentralized crowdsourcing system ZebraLancer. It realizes the fair exchange (i.e. security against malicious workers and dishonest requesters) without using any third-party arbiter. More importantly, it overcomes two fundamental challenges of decentralization, i.e. data leakage and identity breach. First, our outsource-then-prove methodology resolves the critical tension between blockchain transparency and data confidentiality without ...

  1. Using Zebra-speech to study sequential and simultaneous speech segregation in a cochlear-implant simulation.

    Science.gov (United States)

    Gaudrain, Etienne; Carlyon, Robert P

    2013-01-01

    Previous studies have suggested that cochlear implant users may have particular difficulties exploiting opportunities to glimpse clear segments of a target speech signal in the presence of a fluctuating masker. Although it has been proposed that this difficulty is associated with a deficit in linking the glimpsed segments across time, the details of this mechanism are yet to be explained. The present study introduces a method called Zebra-speech developed to investigate the relative contribution of simultaneous and sequential segregation mechanisms in concurrent speech perception, using a noise-band vocoder to simulate cochlear implants. One experiment showed that the saliency of the difference between the target and the masker is a key factor for Zebra-speech perception, as it is for sequential segregation. Furthermore, forward masking played little or no role, confirming that intelligibility was not limited by energetic masking but by across-time linkage abilities. In another experiment, a binaural cue was used to distinguish the target and the masker. It showed that the relative contribution of simultaneous and sequential segregation depended on the spectral resolution, with listeners relying more on sequential segregation when the spectral resolution was reduced. The potential of Zebra-speech as a segregation enhancement strategy for cochlear implants is discussed.

  2. Primary structure of pancreatic polypeptide from four species of Perissodactyla (Przewalski's horse, zebra, rhino, tapir).

    Science.gov (United States)

    Henry, J S; Lance, V A; Conlon, J M

    1991-12-01

    Pancreatic polypeptide (PP) has been purified from extracts of the pancreas of four species of odd-toed ungulates (Perissodactyla): Przewalski's horse, mountain zebra, white rhinoceros, and mountain tapir. The amino acid sequence of Przewalski's horse pancreatic polypeptide was established as Ala-Pro-Met-Glu-Pro-Val-Tyr-Pro-Gly-Asp10-Asn- Ala-Thr-Pro-Glu-Gln-Met-Ala-Gln-Tyr20-Ala-Ala-Glu-Leu-Arg-Arg-Tyr- Ile-Asn-Met30 - Leu-Thr-Arg-Pro-Arg-Tyr.NH2. Zebra PP was identical to Przewalski's horse PP, rhinoceros PP contained three substitutions relative to the horse (Ser for Ala1, Leu for Met3, and Glu for Gln16), and tapir PP contained one substitution relative to the horse (Leu for Met3). On the basis of morphological characteristics and the fossil record, the rhinocerotids are classified with the tapirids in the suborder Ceratomorpha, whereas the horse and zebra belong to a separate suborder, Hippomorpha. On the basis of structural similarity of the PP molecules, however, it would appear that the tapir is more closely related to the horse than to the rhinoceros. These observations provide a further example of the need for extreme caution when inferring taxonomic or phylogenetic relationships between species from the structures of homologous peptides.

  3. Zebra mussel filter feeding and food-limited production of Daphnia: Recent changes in lower trophic level dynamics of Oneida Lake, New York, U.S.A.

    Science.gov (United States)

    Horgan, M.J.; Mills, E.L.

    1999-01-01

    Exotic zebra mussels can alter lower trophic level dynamics in lakes that they colonize by consuming large quantities of phytoplankton. We simulated the indirect effects of zebra mussel grazing on Daphnia by artificially reducing phytoplankton concentration for in situ Daphnia reproduction experiments. The response of Daphnia reproduction to reduced phytoplankton was evaluated for both the in situ experiments and field observations in Oneida Lake, New York, U.S.A. Oneida Lake has had an abundant population of zebra mussels since 1992. Our experiments revealed that fecundity of individuals from two species of Daphnia was positively related to phytoplankton concentration during the spring clearwater phase, although there was no discernible effect of food concentration on fecundity in summer cyanobacteria-dominated assemblages. The experimental results suggest that Daphnia fecundity responds to chlorophyll a concentrations zebra mussels became abundant in Oneida Lake have been characterized by high water clarity, low chlorophyll concentrations, long clearwater phases, and low Daphnia biomass compared with the previous 17 years. The food web effects of zebra mussel grazing are complex and it will take more years for impacts at higher trophic levels to develop and be identified.

  4. Nondestructive detection of zebra chip disease in potatoes using near-infrared spectroscopy

    Science.gov (United States)

    Near-Infrared (NIR) spectroscopy in the wavelength region from 900 nm to 2600 nm was evaluated as the basis for a rapid, non-destructive method for the detection of Zebra Chip disease in potatoes and the measurement of sugar concentrations in affected tubers. Using stepwise regression in conjunction...

  5. Acetylcholinesterase in central vocal control nuclei of the zebra finch ...

    Indian Academy of Sciences (India)

    Unknown

    paring the data to other singing birds and vocalizing birds. As acquisition ..... In Nissl-stained sec- tions, a small RA and area X can be distinguished from ..... Neurol. 356 345–354. Watson J T, Adkins-Regan E, Whiting P, Lindstrom J M and.

  6. Neural mechanisms of song memory formation in juvenile zebra finches

    NARCIS (Netherlands)

    Moorman, S.

    2015-01-01

    There are many parallels between the acquisition of spoken language in human infants and song learning in songbirds, at the behavioural, neural, genetic and cognitive levels. Both human infants and juvenile songbirds are able to imitate sounds from adults of the same species (often their parents),

  7. Accumulation of a low pathogenic avian influenza virus in zebra mussels (Dreissena polymorpha).

    Science.gov (United States)

    Stumpf, Petra; Failing, Klaus; Papp, Tibor; Nazir, Jawad; Böhm, Reinhard; Marschang, Rachel E

    2010-12-01

    In order to investigate the potential role of mussels as a vector of influenza A viruses, we exposed zebra mussels (Dreissena polymorpha) to natural lake water containing a low pathogenic H5N1 avian influenza virus. Mussels were kept in water containing virus for 48 hr, then transferred into fresh water for another 14 days. Virus detection in mussels and water samples was performed by quantitative real-time reverse transcriptase-PCR (qRRT-PCR) and egg culture methods. Virus uptake was detected in all of the mussel groups that were exposed to virus. Even after 14 days in fresh water, virus could still be detected in shellfish material by both qRRT-PCR and egg culture methods. The present study demonstrates that zebra mussels are capable of accumulating influenza A viruses from the surrounding water and that these viruses remain in the mussels over an extended period of time.

  8. Calculations for the intermediate-spectrum cells of Zebra 8 using the MONK Monte-Carlo Code

    International Nuclear Information System (INIS)

    Hanlon, D.; Franklin, B.M.; Stevenson, J.M.

    1987-10-01

    The Monte-Carlo Code MONK 6A and its associated point-energy cross-section data have been used to analyse seven, zero-leakage, plate-geometry cells from the ZEBRA 8 assemblies. The convergence of the calculations was such that the uncertainties in k-infinity and the more important reaction-rate ratios were generally less than the experimental uncertainties. The MONK 6A predictions have been compared with experiment and with predictions from the MURAL collision-probability code. This uses FGL5 data which has been adjusted on the basis of ZEBRA 8 and other integral experiments. The poor predictions from the MONK calculations with errors of up to 10% in k-infinity, are attributed to deficiencies in the database for intermediate to fast spectrum systems. (author)

  9. Non-destructive NIR detection of Zebra Chip disease in whole potatoes (abstract)

    Science.gov (United States)

    Potatoes are the 4th biggest food crop worldwide and the leading vegetable crop in the U.S., accounting for 15 percent of vegetable sales. Over 50% of potatoes are consumed as processed products such as French fries and chips. Zebra Chip (ZC) is a disease of potatoes that causes brown discoloration ...

  10. Pseudodiarrhoea in zebra mussels Dreissena polymorpha (Pallas) exposed to microcystins.

    Science.gov (United States)

    Juhel, Guillaume; Davenport, John; O'Halloran, John; Culloty, Sarah; Ramsay, Ruth; James, Kevin; Furey, Ambrose; Allis, Orla

    2006-03-01

    Microcystins are produced by bloom-forming cyanobacteria and pose significant health and ecological problems. In this study we show that zebra mussels respond differently to different strains of Microcystis aeruginosa, and that a highly toxic strain causes zebra mussels to produce large quantities of mucous pseudofaeces, 'pseudodiarrhoea', that are periodically expelled hydraulically through the pedal gape by shell valve adductions rather than by the normal ciliary tracts. Analysis of the pseudofaecal ejecta showed that the proportion of Microcystis aeruginosa relative to Asterionella formosa was high in the pseudofaeces and even higher in the 'pseudodiarrhoea' when a mixed diet was given to the mussels. This confirms that very toxic Microcystis aeruginosa were preferentially being rejected by comparison with the non-toxic diatom in the pseudofaeces and even more so in the 'pseudodiarrhoea'. Such selective rejection was not observed with low or non-toxic strains and would therefore tend to enhance the presence of toxic Microcystis aeruginosa in mixed Microcystis aeruginosa cyanobacterial blooms, as well as transferring toxins from the water column to the benthos. The observed acute irritant response to the toxin represents the first demonstration of an adverse sublethal effect of microcystins on invertebrate ecophysiology. Our results also suggest that it could be a specific response to microcystin-LF, a little studied toxin variant.

  11. Application of NMR-based metabolomics for environmental assessment in the Great Lakes using zebra mussel (Dreissena polymorpha).

    Science.gov (United States)

    Watanabe, Miki; Meyer, Kathryn A; Jackson, Tyler M; Schock, Tracey B; Johnson, W Edward; Bearden, Daniel W

    Zebra mussel, Dreissena polymorpha , in the Great Lakes is being monitored as a bio-indicator organism for environmental health effects by the National Oceanic and Atmospheric Administration's Mussel Watch program. In order to monitor the environmental effects of industrial pollution on the ecosystem, invasive zebra mussels were collected from four stations-three inner harbor sites (LMMB4, LMMB1, and LMMB) in Milwaukee Estuary, and one reference site (LMMB5) in Lake Michigan, Wisconsin. Nuclear magnetic resonance (NMR)-based metabolomics was used to evaluate the metabolic profiles of the mussels from these four sites. The objective was to observe whether there were differences in metabolite profiles between impacted sites and the reference site; and if there were metabolic profile differences among the impacted sites. Principal component analyses indicated there was no significant difference between two impacted sites: north Milwaukee harbor (LMMB and LMMB4) and the LMMB5 reference site. However, significant metabolic differences were observed between the impacted site on the south Milwaukee harbor (LMMB1) and the LMMB5 reference site, a finding that correlates with preliminary sediment toxicity results. A total of 26 altered metabolites (including two unidentified peaks) were successfully identified in a comparison of zebra mussels from the LMMB1 site and LMMB5 reference site. The application of both uni- and multivariate analysis not only confirmed the variability of altered metabolites but also ensured that these metabolites were identified via unbiased analysis. This study has demonstrated the feasibility of the NMR-based metabolomics approach to assess whole-body metabolomics of zebra mussels to study the physiological impact of toxicant exposure at field sites.

  12. Lake Erie and Lake Michigan zebra mussel settlement monitoring and implications for chlorination treatment

    International Nuclear Information System (INIS)

    Demoss, D.; Mendelsberg, J.I.

    1992-01-01

    This paper reports on the 1991 zebra mussel veliger settlement monitoring program undertaken to record and evaluate zebra mussel veliger settlement in Lake Erie and Lake Michigan. Studies by Dr. Gerald Mackie of Canada in 1990 indicated veliger settlement may be occurring primarily during short time periods every season corresponding with warmer water temperatures. Veliger settlement monitoring was performed using a plexiglass sampler apparatus. The samplers were simple in design and consisted of a 20-inch-square plexiglass base panel with thirty-six 1 inch x 3 inch clear plexiglass microscope slides attached. The results of the monitoring program indicate the existence of preferential settlement periods for veligers correlating with sustained lake water temperatures above 70 degrees F. Veliger settlement concentrations in the south basin of Lake Michigan appear to be similar to those in western Lake Erie

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

    Directory of Open Access Journals (Sweden)

    REYNOLDS J. D.

    2001-04-01

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

  14. Bioavailability of particulate metal to zebra mussels: Biodynamic modelling shows that assimilation efficiencies are site-specific

    Energy Technology Data Exchange (ETDEWEB)

    Bourgeault, Adeline, E-mail: bourgeault@ensil.unilim.fr [Cemagref, Unite de Recherche Hydrosystemes et Bioprocedes, 1 rue Pierre-Gilles de Gennes, 92761 Antony (France); FIRE, FR-3020, 4 place Jussieu, 75005 Paris (France); Gourlay-France, Catherine, E-mail: catherine.gourlay@cemagref.fr [Cemagref, Unite de Recherche Hydrosystemes et Bioprocedes, 1 rue Pierre-Gilles de Gennes, 92761 Antony (France); FIRE, FR-3020, 4 place Jussieu, 75005 Paris (France); Priadi, Cindy, E-mail: cindy.priadi@eng.ui.ac.id [LSCE/IPSL CEA-CNRS-UVSQ, Avenue de la Terrasse, 91198 Gif-sur-Yvette (France); Ayrault, Sophie, E-mail: Sophie.Ayrault@lsce.ipsl.fr [LSCE/IPSL CEA-CNRS-UVSQ, Avenue de la Terrasse, 91198 Gif-sur-Yvette (France); Tusseau-Vuillemin, Marie-Helene, E-mail: Marie-helene.tusseau@ifremer.fr [IFREMER Technopolis 40, 155 rue Jean-Jacques Rousseau, 92138 Issy-Les-Moulineaux (France)

    2011-12-15

    This study investigates the ability of the biodynamic model to predict the trophic bioaccumulation of cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni) and zinc (Zn) in a freshwater bivalve. Zebra mussels were transplanted to three sites along the Seine River (France) and collected monthly for 11 months. Measurements of the metal body burdens in mussels were compared with the predictions from the biodynamic model. The exchangeable fraction of metal particles did not account for the bioavailability of particulate metals, since it did not capture the differences between sites. The assimilation efficiency (AE) parameter is necessary to take into account biotic factors influencing particulate metal bioavailability. The biodynamic model, applied with AEs from the literature, overestimated the measured concentrations in zebra mussels, the extent of overestimation being site-specific. Therefore, an original methodology was proposed for in situ AE measurements for each site and metal. - Highlights: > Exchangeable fraction of metal particles did not account for the bioavailability of particulate metals. > Need for site-specific biodynamic parameters. > Field-determined AE provide a good fit between the biodynamic model predictions and bioaccumulation measurements. - The interpretation of metal bioaccumulation in transplanted zebra mussels with biodynamic modelling highlights the need for site-specific assimilation efficiencies of particulate metals.

  15. Comparison of the acute toxicity for gamma-cyhalothrin and lambda-cyhalothrin to zebra fish and shrimp.

    Science.gov (United States)

    Wang, Wei; Cai, D J; Shan, Z J; Chen, W L; Poletika, Nick; Gao, X W

    2007-03-01

    Gamma-cyhalothrin 15CS (GCH) contains only the active stereoisomer of the two isomers found in lambda-cyhalothrin 25EW (LCH). GCH (0.5 x rate) provides equivalent overall insect control as LCH (1 x rate). Both formulations showed high acute toxicity to zebra fish (Brachydanio rerio H.B.) and shrimp (Macrobrachium nippoensis de Haan). The 96-h LC(50(zebra fish,GCH)) is 1.93 microg a.i/L and LC(50(zebra fish,LCH)) is 1.94 microg a.i/L. LC(50(shrimp,GCH)) is 0.28 microg a.i./L and LC(50(shrimp,LCH)) 0.04 microg a.i./L. This indicates that the toxicity to shrimp is likely stereochemistry-dependent. The fates of GCH and LCH are similar in laboratory simulated rice paddy water and their concentrations decrease rapidly, with no GCH or LCH detected after 3 or 4 days. Both are toxic to shrimp in a simulated paddy irrigation reservoir even though treated return water is diluted 5 times. No shrimp fatality is shown in the GCH-treated paddy water after a 4-day holding period, and longer than 5 days is necessary to reach a zero fatality rate for LCH. This is compatible with the 7-day water holding period considered reasonable in agricultural practice.

  16. Will the Displacement of Zebra Mussels by Quagga Mussels Increase Water Clarity in Shallow Lakes during Summer? Results from a Mesocosm Experiment.

    Directory of Open Access Journals (Sweden)

    Xueying Mei

    Full Text Available Zebra mussels (Dreissena polymorpha are known to increase water clarity and affect ecosystem processes in invaded lakes. During the last decade, the conspecific quagga mussels (D. rostriformis bugensis have displaced zebra mussels in many ecosystems including shallow lakes such as Oneida Lake, New York. In this study, an eight-week mesocosm experiment was conducted to test the hypothesis that the displacement of zebra mussels by quagga mussels leads to further decreases in phytoplankton and increases in water clarity resulting in increases in benthic algae. We found that the presence of zebra mussels alone (ZM, quagga mussels alone (QM, or an equal number of both species (ZQ reduced total phosphorus (TP and phytoplankton Chl a. Total suspended solids (TSS was reduced in ZM and ZQ treatments. Light intensity at the sediment surface was higher in all three mussel treatments than in the no-mussel controls but there was no difference among the mussel treatments. There was no increase in benthic algae biomass in the mussel treatments compared with the no-mussel controls. Importantly, there was no significant difference in nutrient (TP, soluble reactive phosphorus and NO3- levels, TSS, phytoplankton Chl a, benthic algal Chl a, or light intensity on the sediment surface between ZM, QM and ZQ treatments. These results confirm the strong effect of both mussel species on water clarity and indicate that the displacement of zebra mussel by an equivalent biomass of quagga mussel is not likely to lead to further increases in water clarity, at least for the limnological conditions, including summer temperature, tested in this experiment.

  17. Will the Displacement of Zebra Mussels by Quagga Mussels Increase Water Clarity in Shallow Lakes during Summer? Results from a Mesocosm Experiment.

    Science.gov (United States)

    Mei, Xueying; Zhang, Xiufeng; Kassam, Sinan-Saleh; Rudstam, Lars G

    2016-01-01

    Zebra mussels (Dreissena polymorpha) are known to increase water clarity and affect ecosystem processes in invaded lakes. During the last decade, the conspecific quagga mussels (D. rostriformis bugensis) have displaced zebra mussels in many ecosystems including shallow lakes such as Oneida Lake, New York. In this study, an eight-week mesocosm experiment was conducted to test the hypothesis that the displacement of zebra mussels by quagga mussels leads to further decreases in phytoplankton and increases in water clarity resulting in increases in benthic algae. We found that the presence of zebra mussels alone (ZM), quagga mussels alone (QM), or an equal number of both species (ZQ) reduced total phosphorus (TP) and phytoplankton Chl a. Total suspended solids (TSS) was reduced in ZM and ZQ treatments. Light intensity at the sediment surface was higher in all three mussel treatments than in the no-mussel controls but there was no difference among the mussel treatments. There was no increase in benthic algae biomass in the mussel treatments compared with the no-mussel controls. Importantly, there was no significant difference in nutrient (TP, soluble reactive phosphorus and NO3-) levels, TSS, phytoplankton Chl a, benthic algal Chl a, or light intensity on the sediment surface between ZM, QM and ZQ treatments. These results confirm the strong effect of both mussel species on water clarity and indicate that the displacement of zebra mussel by an equivalent biomass of quagga mussel is not likely to lead to further increases in water clarity, at least for the limnological conditions, including summer temperature, tested in this experiment.

  18. Identification of larvae: The zebra mussel (Dreissena polymorpha), quagga mussel (Dreissena rosteriformis bugensis), and Asian clam (Corbicula fluminea)

    Science.gov (United States)

    Nichols, S. Jerrine; Black, M.G.

    1994-01-01

    There are presently four freshwater bivalves in the United States that produce larvae or veligers commonly found in the water column: two forms of Asian clams and two species of dreissenids. Portions of the geographic range of three of these bivalves, one species of Asian clam (Corbicula fluminea), zebra mussels (Dreissena polymorpha), and quagga mussels (Dreissena rosteriformis bugensis), overlap, causing problems with larval identification. To determine which characteristics can be used to separate larval forms, adult Asian clams, quaggas, and zebra mussels were brought into the laboratory and induced to spawn, and the resulting larvae were reared. Hybrids between quaggas and zebra mussels were also produced, but not reared to maturity. Characteristics allowing for the most rapid and accurate separation of larvae were hinge length, shell length/height, shell shape, shell size, and the presence or absence of a foot and velum. These characteristics were observed in laboratory-reared larvae of known parentage and field-caught larvae of unknown parentage. In most cases, larvae of the Asian clam can be readily separated from those produced by either type of dreissenid on the basis of shell size and presence of a foot. Separating the gametes and embryos of the two types of dreissenids is not possible, but after shell formation, most of the larval stages can be distinguished. Hinge length, shell length/height, and the similarity in size of the shell valves can be used to separate straight-hinged, umbonal, pediveliger, and plantigrade larvae. Quagga × zebra mussel hybrids show characteristics of both parents and are difficult to identify.

  19. Working towards developing potato tolerance of zebra chip disease: a food science perspective

    Science.gov (United States)

    Potato zebra chip is a major threat to worldwide potato production and is caused by ‘Candidatus Liberibacter solanacearum’ (Lso), which is vectored by potato psyllids. Albeit control can be achieved by use of insecticides to limit psyllid populations and therefore Lso spread, the recent development ...

  20. Basal metabolic rate can evolve independently of morphological and behavioural traits.

    Science.gov (United States)

    Mathot, K J; Martin, K; Kempenaers, B; Forstmeier, W

    2013-09-01

    Quantitative genetic analyses of basal metabolic rate (BMR) can inform us about the evolvability of the trait by providing estimates of heritability, and also of genetic correlations with other traits that may constrain the ability of BMR to respond to selection. Here, we studied a captive population of zebra finches (Taeniopygia guttata) in which selection lines for male courtship rate have been established. We measure BMR in these lines to see whether selection on male sexual activity would change BMR as a potentially correlated trait. We find that the genetic correlation between courtship rate and BMR is practically zero, indicating that the two traits can evolve independently of each other. Interestingly, we find that the heritability of BMR in our population (h(2)=0.45) is markedly higher than was previously reported for a captive zebra finch population from Norway. A comparison of the two studies shows that additive genetic variance in BMR has been largely depleted in the Norwegian population, especially the genetic variance in BMR that is independent of body mass. In our population, the slope of BMR increase with body mass differs not only between the sexes but also between the six selection lines, which we tentatively attribute to genetic drift and/or founder effects being strong in small populations. Our study therefore highlights two things. First, the evolvability of BMR may be less constrained by genetic correlations and lack of independent genetic variation than previously described. Second, genetic drift in small populations can rapidly lead to different evolvabilities across populations.

  1. Zebra Crossing: Walking in Two Continents Sharing and Celebrating Difference through Music

    Science.gov (United States)

    Joseph, Dawn

    2011-01-01

    I use the metaphor "zebra crossing" in my reflective narrative to describe my plight and struggle as a non-white person growing up and working in Johannesburg, South Africa, during the apartheid era. This article considers and compares the notions of culture, diversity and identity as I now work in a tertiary institution in Melbourne,…

  2. Double plasma resonance instability as a source of solar zebra emission

    Science.gov (United States)

    Benáček, J.; Karlický, M.

    2018-03-01

    Context. The double plasma resonance (DPR) instability plays a basic role in the generation of solar radio zebras. In the plasma, consisting of the loss-cone type distribution of hot electrons and much denser and colder background plasma, this instability generates the upper-hybrid waves, which are then transformed into the electromagnetic waves and observed as radio zebras. Aims: In the present paper we numerically study the double plasma resonance instability from the point of view of the zebra interpretation. Methods: We use a 3-dimensional electromagnetic particle-in-cell (3D PIC) relativistic model. We use this model in two versions: (a) a spatially extended "multi-mode" model and (b) a spatially limited "specific-mode" model. While the multi-mode model is used for detailed computations and verifications of the results obtained by the "specific-mode" model, the specific-mode model is used for computations in a broad range of model parameters, which considerably save computational time. For an analysis of the computational results, we developed software tools in Python. Results: First using the multi-mode model, we study details of the double plasma resonance instability. We show how the distribution function of hot electrons changes during this instability. Then we show that there is a very good agreement between results obtained by the multi-mode and specific-mode models, which is caused by a dominance of the wave with the maximal growth rate. Therefore, for computations in a broad range of model parameters, we use the specific-mode model. We compute the maximal growth rates of the double plasma resonance instability with a dependence on the ratio between the upper-hybrid ωUH and electron-cyclotron ωce frequency. We vary temperatures of both the hot and background plasma components and study their effects on the resulting growth rates. The results are compared with the analytical ones. We find a very good agreement between numerical and analytical growth

  3. Use of a barbed tool by an adult and a juvenile woodpecker finch (Cactospiza pallida).

    Science.gov (United States)

    Sabine, Tebbich; Irmgard, Teschke; Erica, Cartmill; Sophia, Stankewitz

    2012-02-01

    Here we describe the modification and use of a new tool type in the woodpecker finch (Cactospiza pallida). This species is known to habitually use twigs or cactus spines to extract arthropods out of tree holes. We observed an adult and a juvenile bird using several barbed twigs from introduced blackberry bushes (Rubus niveus) which the adult bird had first modified by removing leaves and side twigs. The barbs of blackberry tools provide a novel functional feature not present in tools made from native plants and de-leafing of twigs never has been observed before. Both birds were observed using several of these tools to extract prey from under the bark of the native scalesia tree (Scalesia penduculta). They oriented the twigs such that the barbs pointed towards themselves; this rendered the barbs functional as they could be used to drag prey out of a crevice. The juvenile bird first watched the adult using the tool and then used the tool that the adult bird had left under the bark at the same location and in the same way as the adult. Our observation highlights the fact that opportunities for the transmission of social information do occur in the wild and indicates that woodpecker finches are flexible in their choice of tool material and tool modification. Copyright © 2011 Elsevier B.V. All rights reserved.

  4. Annually recurring parthenogenesis in a zebra shark Stegostoma fasciatum.

    Science.gov (United States)

    Robinson, D P; Baverstock, W; Al-Jaru, A; Hyland, K; Khazanehdari, K A

    2011-11-01

    A zebra shark, Stegostoma fasciatum, held in captivity at the Burj Al Arab aquarium, produced embryos and pups in the absence of a male. A total of 15 pups were produced from eggs laid within the aquarium over a period of four consecutive years commencing 2007. Parthenogenesis was confirmed through DNA analysis for three pups sampled during the first two consecutive egg cycles and is presumed to be the method of reproduction responsible thereafter. © 2011 The Authors. Journal of Fish Biology © 2011 The Fisheries Society of the British Isles.

  5. DNA adduct measurements in zebra mussels, Dreissena polymorpha, Pallas. Potential use for genotoxicant biomonitoring of fresh water ecosystems.

    Science.gov (United States)

    Le Goff, J; Gallois, J; Pelhuet, L; Devier, M H; Budzinski, H; Pottier, D; André, V; Cachot, J

    2006-08-12

    The purpose of this study was to examine PAH accumulation and bulky DNA adduct formation in the digestive gland of zebra mussels exposed in their habitat or in controlled laboratory conditions to complex mixture of PAH. DNA adducts were measured using a 32P-postlabelling protocol with nuclease P1 enrichment adapted from Reddy and Randerath [Reddy, M.V., Randerath, K., 1986. Nuclease P1-mediated enhancement of sensitivity of 32P-postlabelling test for structurally diverse DNA adducts. Carcinogenesis 7, 1543-1551]. Specimens collected in the upper part of the Seine estuary were shown to accumulate higher levels of PAH (up to 1.6 microg g(-1) dry weight) in comparison to individuals from the reference site (0.053 microg g(-1) dry weight). The former exhibited elevated levels of DNA adducts (up to 4.0/10(8) nucleotides) and higher diversity of individual adducts with five distinct spots being specifically detected in individuals originating from the Seine estuary. Zebra mussels exposed for 5 days to 0.01% (v/v) of organic extract of sediment from the Seine estuary were shown to accumulate high amounts of PAH (up to 138 microg g(-1) dry weight) but exhibited relatively low levels of DNA adducts. Exposure to benzo[a]pyrene led to a dose-dependent accumulation of B[a]P (up to 7063 microg g(-1) dry weight) and a clear induction of DNA adduct formation in the digestive gland of mussels (up to 1.13/10(8) nucleotides). Comparisons with other bivalves exposed to the same model PAH, revealed similar levels of adducts and comparable adduct profiles with a main adduct spot and a second faint one. This study clearly demonstrated that zebra mussels are able to biotransform B[a]P and probably other PAH into reactive metabolites with DNA-binding activity. This work also demonstrated the applicability of the nuclease P1 enhanced 32P-postlabelling method for bulky adduct detection in the digestive gland of zebra mussels. DNA adduct measurement in zebra mussels could be a suitable

  6. Comparing a microbial biocide and chlorine as zebra mussel control strategies in an Irish drinking water treatment plant

    Directory of Open Access Journals (Sweden)

    Sara Meehan

    2013-06-01

    Full Text Available A need exists for an environmentally friendly mussel control method to replace chlorine and other traditional control methods currentlyutilised in drinking water plants and other infested facilities. Zequanox® is a newly commercialised microbial biocide for zebra and quaggamussels comprised of killed Pseudomonas fluorescens CL145A cells. The objective of this study was to compare the efficacy of adevelopmental formulation of Zequanox (referred to as MBI 401 FDP and chlorine treatments on adult and juvenile zebra mussels byrunning a biobox trial in conjunction with chlorine treatments at an infested Irish drinking water treatment plant. Since 2009, the plantmanagement has used a residual chlorine concentration of 2 mg/L in autumn to control both adult zebra mussels and juvenile settlement intheir three concrete raw water chambers. Juvenile mussel settlement was monitored in three bioboxes as well as in three treatment chambersin the plant for three months prior to treatment. Adult mussels were seeded into the chambers and bioboxes four days before treatment. InOctober 2011, the bioboxes were treated with MBI 401 FDP at 200 mg active substance/L, while chlorine treatment took place in the waterchambers. The MBI 401 FDP treatment lasted only 8 hours while chlorine treatment lasted seven days. Juvenile numbers were reduced tozero in both the bioboxes and treated chambers within seven days. Adult mussel mortality reached 80% for both the chlorine and MBI 401FDP treatment; however, mortality was achieved faster in the chlorine treatment. These results provided important insights into zebra musselcontrol alternatives to chlorine and supported further development of the now commercial product, Zequanox.

  7. The zebra mussel (Dreissena polymorpha), a new pest in North America: reproductive mechanisms as possible targets of control strategies

    Science.gov (United States)

    Ram, Jeffrey L.; Fong, Peter; Croll, Roger P.; Nichols, Susan J.; Wall, Darcie

    1992-01-01

    The zebra mussel (Dreissena polymorpha) has spread rapidly in temperate fresh waters of North America since its introduction into the Great Lakes in 1985 or 1986. It attaches to hard substrates, forming layers, occluding water intakes, encrusting and killing native mussels, filtering algae in competition with other planktivores, and possibly interfering with fish spawning. It reproduces prolifically, suggesting that an approach to its control may be by controlling its reproduction. Previous literature suggests that spawning in bivalves is regulated by both environmental and internal chemical cues. A suggested sequence is that phytoplankton chemicals initially trigger spawning; chemicals associated with gametes provide a species-specific pheromonal positive feedback for spawning; and the response to environmental chemicals is mediated internally by serotonin (5-HT). The role of 5-HT in zebra mussels is under investigation. Both males and females can be induced to spawn by either injection or external application of 5-HT. The response can also be activated by 8-hydroxy-2-(di-n-propylamino)-tetralin, an agonist at 5-HT1A receptors. HPLC analysis has detected 5-HT as the major biogenic amine in both male and female gonads. 5-HT immunocytochemistry demonstrates nerves containing serotonergic fibers innervating gonads of both males and females, with prominent varicosities surrounding the follicles in both sexes. A role of 5-HT in mediating spawning responses in zebra mussels is thus strongly supported. These studies have shown that reproductive behavior of zebra mussels can be modified by outside chemicals, a property that may be exploited for purposes of control.

  8. Human waterborne parasites in zebra mussels ( Dreissena polymorpha) from the Shannon River drainage area, Ireland.

    Science.gov (United States)

    Graczyk, Thaddeus K; Conn, David Bruce; Lucy, Frances; Minchin, Dan; Tamang, Leena; Moura, Lacy N S; DaSilva, Alexandre J

    2004-08-01

    Zebra mussels ( Dreissena polymorpha) from throughout the Shannon River drainage area in Ireland were tested for the anthropozoonotic waterborne parasites Cryptosporidium parvum, Giardia lamblia, Encephalitozoon intestinalis, E. hellem, and Enterocytozoon bieneusi, by the multiplexed combined direct immunofluorescent antibody and fluorescent in situ hybridization method, and PCR. Parasite transmission stages were found at 75% of sites, with the highest mean concentration of 16, nine, and eight C. parvum oocysts, G. lamblia cysts, and Encephalitozoon intestinalis spores/mussel, respectively. On average eight Enterocytozoon bieneusi spores/mussel were recovered at any selected site. Approximately 80% of all parasites were viable and thus capable of initiating human infection. The Shannon River is polluted with serious emerging human waterborne pathogens including C. parvum, against which no therapy exists. Zebra mussels can recover and concentrate environmentally derived pathogens and can be used for the sanitary assessment of water quality.

  9. Camdeboo-Mountain Zebra National Park Corridor: Opportunities for conservation and socio-economic development

    Science.gov (United States)

    Matthew Norval

    2015-01-01

    The Wilderness Foundation, in partnership with South African National Parks has initiated a two year project in the Karoo; The Mountain Zebra-Camdeboo Corridor Project. Through either voluntary Contractual National Park or Protected Environment agreements, the project aims to work with, rather than displace, current conservation-compatible land-use practices such as...

  10. VizieR Online Data Catalog: URAT Parallax Catalog (UPC) (Finch+, 2016)

    Science.gov (United States)

    Finch, C. T.; Zacharias, N.

    2016-04-01

    The URAT Parallax Catalog (UPC) consists of 112177 parallaxes. The catalog utilizes all Northern Hemisphere epoch data from the United States Naval Observatory (USNO) Robotic Astrometric Telescope (URAT). This data includes all individual exposures from April 2012 to June 2015 giving a larger epoch baseline for determining parallaxes over the 2-year span of the First USNO Robotic Astrometric Telescope Catalog (URAT1) (Zacharias et al., 2015, Cat. I/329) published data. The URAT parallax pipeline is custom code that utilizes routines from (Jao, C.-W., 2004, PhD thesis Georgia Stat), the JPL DE405 ephemeris and Green's parallax factor (Green, R.M., 1985, Spherical Astronomy) for determining parallaxes from a weighted least-squares reduction. The relative parallaxes have been corrected to absolute by using the distance color relation described in (Finch et. al, 2014, Cat. J/AJ/148/119) to determine a mean distance of all UCAC4 reference stars (R=8-16 mag) used in the astrometric reductions. Presented here are all significant parallaxes from the URAT Northern Hemisphere epoch data comprising of 2 groups: a) URAT parallax results for stars with prior published parallax, and b) first time trigonometric parallaxes as obtained from URAT data of stars without prior published parallax. Note, more stringent selection criteria have been applied to the second group than the first in order to keep the rate of false detections low. For specific information about the astrometric reductions please see 'The First U.S. Naval Observatory Robotic Astrometric Telescope Catalog' published paper (Zacharias et al., 2015AJ....150..101Z, Cat. I/329). For complete details regarding the parallax pipeline please see 'Parallax Results From URAT Epoch Data' (Finch and Zacharias, 2016, AJ, in press). This catalog gives all positions on the ICRS at Epoch J2014.0; it covers the magnitude range 6.56 to 16.93 in the URAT band-pass, with an average parallax precision of 4.3mas for stars having no known

  11. Todralazine protects zebra fish from lethal doses of ionizing radiation: role of hematopoietic stem cell expansion

    International Nuclear Information System (INIS)

    Dimri, Manali; Joshi, Jaidev; Indracanti, Prem Kumar

    2013-01-01

    Radiation induced cell killing and hematopoietic stem cell depletion leads to compromised immune functions and opportunistic infections which significantly affect the recovery and survival upon irradiation. Any agent which can expand residual hematopoietic stem cells in irradiated organism can render protection from the effects of lethal doses of ionizing radiation. Johns Hopkins Clinical compound library (JHCCL) was screened for protection against lethal doses of ionizing radiation using developing zebra fish as a model organism. Modulation of radiation induced reactive oxygen species by the small molecules were done by DCFDA staining and for visual identification and quantification of apoptosis acridine orange assay, flow cytometry were employed respectively. Hematopoietic stem cell expansion potential was assessed by quantifying runx1 expression, a marker for definitive stem cells, were done by RT-PCR and by the kinetics of recovery from chemically induced anaemia. Todralazine hydrochloride from JHCCL exhibited promising results with potential anti radiation effects. A dose of 5μM was found to be the most effective and has rendered significant organ and whole body protection (100% survival advantage over a period of 6 days) against 20 Gy. However todralazine did not modulated radiation induced free radicals (monitored within 2 h of irradiation) and apoptosis in zebra fish embryos analysed at 8 and 24h post irradiation. Flow cytometric quantification of pre G1 population suggested the same. Chemoinformatics approaches were further carried out to elucidate possible targets which are contributing to its radioprotection potential. Structural similarity search suggested several targets and possible hematopoietic stem cell expanding potential. Treatment of zebra fish embryos with todralazine has lead to significant proliferation of hematopoietic stem cell as indicated by increase in expression of runx1. HSC expanding potential of todralazine was further supported by

  12. Variations in Zebra Chip disease expression and tuber biochemistry in response to vector density

    Science.gov (United States)

    This study examined effects of the number of ‘Candidatus Liberibacter solanacearum’ (Lso)-positive psyllids feeding on potatoes to Lso titers, zebra chip disease (ZC) symptom severity, and levels of amino acids, carbohydrates, and phenolics in tubers harvested weeks later. Red La Soda and Russet Nor...

  13. Haplosporidium raabei n. sp. (Haplosporidia): a parasite of zebra mussels, Dreissena polymorpha (Pallas, 1771).

    Science.gov (United States)

    Molloy, D P; Giambérini, L; Stokes, N A; Burreson, E M; Ovcharenko, M A

    2012-04-01

    Extensive connective tissue lysis is a common outcome of haplosporidian infection. Although such infections in marine invertebrates are well documented, they are relatively rarely observed in freshwater invertebrates. Herein, we report a field study using a comprehensive series of methodologies (histology, dissection, electron microscopy, gene sequence analysis, and molecular phylogenetics) to investigate the morphology, taxonomy, systematics, geographical distribution, pathogenicity, and seasonal and annual prevalence of a haplosporidian observed in zebra mussels, Dreissena polymorpha. Based on its genetic sequence, morphology, and host, we describe Haplosporidium raabei n. sp. from D. polymorpha - the first haplosporidian species from a freshwater bivalve. Haplosporidium raabei is rare as we observed it in histological sections in only 0·7% of the zebra mussels collected from 43 water bodies across 11 European countries and in none that were collected from 10 water bodies in the United States. In contrast to its low prevalences, disease intensities were quite high with 79·5% of infections advanced to sporogenesis.

  14. Chronological history of zebra and quagga mussels (Dreissenidae) in North America, 1988-2010

    Science.gov (United States)

    Benson, Amy J.

    2013-01-01

    An unprecedented invasion began in North America in the mid-/late-1980s when two Eurasian mussel species, Dreissena polymorpha (zebra mussel) and Dreissena rostriformis bugensis (quagga mussel), became established in Laurentian Great Lakes. It is believed that Lake Erie was the initial location of establishment for both species, and within 3 years, zebra mussels had been found in all the Great Lakes. Since 1986, the combined distribution of two dreissenids has expanded throughout the Great Lakes region and the St. Lawrence River in Canada and also in the United States from the Great Lakes to the Mississippi Basin including Arkansas, Cumberland, Illinois, Missouri, Ohio, and Tennessee river basins. The distribution of dreissenid mussels in the Atlantic drainage has been limited to the Hudson and Susquehanna rivers. In the western United States, the quagga mussel established a large population in the lower Colorado River and spread to reservoirs in Arizona, California, Colorado, Nevada, and Utah. Overall, dreissenid species have been documented in 131 river systems and 772 inland lakes, reservoirs, and impoundments in the United States.

  15. Bisphosphonate-induced zebra lines in fibrous dysplasia of bone: histo-radiographic correlation in a case of McCune-Albright syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Corsi, Alessandro; Riminucci, Mara [Sapienza University, Department of Molecular Medicine, Rome (Italy); Ippolito, Ernesto [University of Rome Tor Vergata, Department of Orthopaedic Surgery, Rome (Italy); Robey, Pamela G. [Skeletal Biology Section, National Institute of Dental and Craniofacial Research, National Institutes of Health, Department of Health and Human Services, Bethesda, MD (United States); Boyde, Alan [Queen Mary University of London, Dental Physical Sciences, London (United Kingdom)

    2017-10-15

    Bisphosphonates (BPs) are currently used in the treatment of diverse bone diseases including fibrous dysplasia of bone (FD). In pediatric patients, a radiographic consequence of cyclical administration of BPs is the development of apo-, epi-, and meta-physeal sclerotic bands, otherwise known as zebra lines, which result from the temporary inhibition of osteoclastic activity at the time of drug treatment. We report here on a child with McCune-Albright syndrome (FD in addition to hyperfunctioning endocrinopathies and skin hyperpigmentation) treated with cyclical intravenous infusions of pamidronate in which conventional radiography, contact microradiography, histology, and backscattered electron image analysis demonstrated that zebra lines formed only where bone was normal, were arrested at the boundary between FD-unaffected and FD-affected bone where bone is sclerotic, and were absent within the undermineralized FD bone. Moreover, in spite of the treatment, the FD lesions continued to expand. This case report is unique because no previously published studies correlated the radiographic and the histologic features of BP-induced zebra lines in the metaphysis of an FD-affected long bone of the limbs. (orig.)

  16. Bisphosphonate-induced zebra lines in fibrous dysplasia of bone: histo-radiographic correlation in a case of McCune-Albright syndrome

    International Nuclear Information System (INIS)

    Corsi, Alessandro; Riminucci, Mara; Ippolito, Ernesto; Robey, Pamela G.; Boyde, Alan

    2017-01-01

    Bisphosphonates (BPs) are currently used in the treatment of diverse bone diseases including fibrous dysplasia of bone (FD). In pediatric patients, a radiographic consequence of cyclical administration of BPs is the development of apo-, epi-, and meta-physeal sclerotic bands, otherwise known as zebra lines, which result from the temporary inhibition of osteoclastic activity at the time of drug treatment. We report here on a child with McCune-Albright syndrome (FD in addition to hyperfunctioning endocrinopathies and skin hyperpigmentation) treated with cyclical intravenous infusions of pamidronate in which conventional radiography, contact microradiography, histology, and backscattered electron image analysis demonstrated that zebra lines formed only where bone was normal, were arrested at the boundary between FD-unaffected and FD-affected bone where bone is sclerotic, and were absent within the undermineralized FD bone. Moreover, in spite of the treatment, the FD lesions continued to expand. This case report is unique because no previously published studies correlated the radiographic and the histologic features of BP-induced zebra lines in the metaphysis of an FD-affected long bone of the limbs. (orig.)

  17. Body size-dependent Cd accumulation in the zebra mussel Dreissena polymorpha from different routes.

    Science.gov (United States)

    Tang, Wen-Li; Evans, Douglas; Kraemer, Lisa; Zhong, Huan

    2017-02-01

    Understanding body size-dependent metal accumulation in aquatic organisms (i.e., metal allometry) is critical in interpreting biomonitoring data. While growth has received the most attention, little is known about controls of metal exposure routes on metal allometry. Here, size-dependent Cd accumulation in zebra mussels (Dreissena polymorpha) from different routes were investigated by exposing mussels to A.( 111 Cd spiked algae+ 113 Cd spiked river water) or B.( 111 Cd spiked sediments+ 113 Cd spiked river water). After exposure, 111 Cd or 113 Cd levels in mussel tissue were found to be negatively correlated with tissue weight, while Cd allometry coefficients (b values) were dependent on Cd exposure routes: -0.664 for algae, -0.241 for sediments and -0.379 for river water, compared to -0.582 in un-exposed mussels. By comparing different Cd exposure routes, we found that size-dependent Cd bioaccumulation from algae or river water could be more responsible for the overall size-dependent Cd accumulation in mussels, and the relative importance of the two sources was dependent on mussel size ranges: Cadmium obtained from algae (algae-Cd) was more important in size-dependent Cd accumulation in smaller mussels (tissue dry weight  5 mg). In contrast, sediment-Cd contributed only a small amount to Cd accumulation in zebra mussels and may have little effect on size-dependent Cd bioaccumulation. Our results suggest that size-dependent Cd accumulation in mussels could be largely affected by exposure routes, which should be considered when trying to interpret Cd biomonitoring data of zebra mussels. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Male harassment influences female movements and associations in Grevy's zebra (Equus grevyi)

    OpenAIRE

    Siva R. Sundaresan; Ilya R. Fischhoff; DI Rubenstein

    2007-01-01

    In traditional models for social organization, female movements and association patterns track resource distribution, whereas males track females. More recently, this model has been expanded to include feedback effects of male behavior, especially sexual harassment, on female decisions. In Grevy's zebra (Equus grevyi), males defend territories containing resources attractive to females, who form unstable groups. Past research has explained female behavior based on resource distribution and ne...

  19. Factors Affecting Zebra Mussel Kill by the Bacterium Pseudomonas fluorescens

    Energy Technology Data Exchange (ETDEWEB)

    Daniel P. Molloy

    2004-02-24

    The specific purpose of this research project was to identify factors that affect zebra mussel kill by the bacterium Pseudomonas fluorescens. Test results obtained during this three-year project identified the following key variables as affecting mussel kill: treatment concentration, treatment duration, mussel siphoning activity, dissolved oxygen concentration, water temperature, and naturally suspended particle load. Using this latter information, the project culminated in a series of pipe tests which achieved high mussel kill inside power plants under once-through conditions using service water in artificial pipes.

  20. Limb salvage and reconstruction following a zebra attack

    Directory of Open Access Journals (Sweden)

    Jacob T. Carlson

    2017-06-01

    Full Text Available Animal bites are fairly rare events but can cause devastating traumatic injuries to the victim. In addition to the soft tissue, vascular, and orthopedic trauma inflicted by these occurrences, bite injuries also have the potential to introduce an inoculum of microbes, which may progress to an infection if not treated properly and expeditiously.We present the case of a healthy male who sustained multiple bite wounds from a domestic zebra to his left upper extremity. This attack caused severe damage, including devascularization of the arm at the brachial artery, disruption of the distal biceps and brachialis, stripping of the forearm nerves, and shearing of the overlying soft tissue. The patient was taken emergently to the operating room for revascularization of the extremity utilizing a vein bypass graft. The soft tissue injuries were addressed with numerous irrigation and debridement procedures, during which coverage of the vein bypass graft was obtained using a variety of techniques, including skin flaps, musculocutaneous advancements, and the application of an acellular dermal matrix (AlloDerm and a collagen-glycosaminoglycan matrix (Integra.Wound cultures obtained intra-operatively during the irrigation and debridement procedures were notable for the growth of multiple microbes, including Rhodococcus spp., which have been documented to cause infection in immunocompromised patients. The patient in this case was treated with a prolonged course of antibiotics, and wound cultures negative for microbial growth were eventually obtained prior to final closure of his wound. The patient then underwent successful biceps reconstruction with a pedicled latissimus dorsi muscle transfer. This case documents the extraordinary multidisciplinary approach provided in the salvage, management, and eventual reconstruction of a mangled left upper extremity that had sustained devastating traumatic injuries resulting from a rather unusual source. Keywords: Zebra

  1. Effects of suspended sediments on food uptake for zebra mussels in Lake Markermeer, The Netherlands

    NARCIS (Netherlands)

    Penning, W.E.; Pozzato, L.; Vijverberg, T.; Noordhuis, R.; bij de Vaate, A.; Van Donk, E.; Dionisio Pires, L.M.

    2013-01-01

    Until 1992, zebra mussels (Dreissena polymorpha) were an important food source for diving ducks in Lake Markermeer (The Netherlands). After 1993, the mussel biomass sharply declined, and the current population is in poor condition (maximum shell length <15 mm) compared to populations from adjacent

  2. Safeguards sealing systems for Zebra

    International Nuclear Information System (INIS)

    Ingram, G.; Jamieson, G.R.

    1983-01-01

    A relatively simple design has been produced for safeguards seals to be applied throughout the fuel containing areas at Zebra. It is based on the use of wire seals and regular Inspector surveillance. The application of the system would allow an Inspector to establish to a high degree of confidence that significant quantities of fuel had not been diverted during an intensive experimental programme. It would add about 5% to the time required for experiments, and careful planning would reduce this value. The inspection effort required to witness element movements during the experimental programme would average about 2 hours per day, with a further 2 hours spent each week on NDA of the fuel exposed. The Safeguards Inspector would require to spend about 25% of his time in the reactor area and would have ample time to deal with the relatively small number of fuel movements taking place in the storage area and with his duties elsewhere in the plant. During a core change, full-time inspection effort would be required for about 6 weeks each year. (author)

  3. How landscape scale changes affect ecological processes in conservation areas: external factors influence land use by zebra (Equus burchelli) in the Okavango Delta.

    Science.gov (United States)

    Bartlam-Brooks, Hattie L A; Bonyongo, Mpaphi C; Harris, Stephen

    2013-09-01

    Most large-bodied wildlife populations in sub-Saharan Africa only survive in conservation areas, but are continuing to decline because external changes influence ecological processes within reserves, leading to a lack of functionality. However, failure to understand how landscape scale changes influence ecological processes limits our ability to manage protected areas. We used GPS movement data to calculate dry season home ranges for 14 zebra mares in the Okavango Delta and investigated the effects of a range of landscape characteristics (number of habitat patches, mean patch shape, mean index of juxtaposition, and interspersion) on home range size. Resource utilization functions (RUF) were calculated to investigate how specific landscape characteristics affected space use. Space use by all zebra was clustered. In the wetter (Central) parts of the Delta home range size was negatively correlated with the density of habitat patches, more complex patch shapes, low juxtaposition of habitats and an increased availability of floodplain and grassland habitats. In the drier (Peripheral) parts of the Delta, higher use by zebra was also associated with a greater availability of floodplain and grassland habitats, but a lower density of patches and simpler patch shapes. The most important landscape characteristic was not consistent between zebra within the same area of the Delta, suggesting that no single foraging strategy is substantially superior to others, and so animals using different foraging strategies may all thrive. The distribution and complexity of habitat patches are crucial in determining space use by zebra. The extent and duration of seasonal flooding is the principal process affecting habitat patch characteristics in the Okavango Delta, particularly the availability of floodplains, which are the habitat at greatest risk from climate change and anthropogenic disturbance to the Okavango's catchment basin. Understanding how the factors that determine habitat

  4. The Zebra Battery: a South African contender for electric vehicle application

    Directory of Open Access Journals (Sweden)

    J. Coertzer

    1996-07-01

    Full Text Available The Zebra battery is one of the most promising power sources for electric vehicles which might be on sale before the year 2000. It is a South African development which started at the CSIR and is at present jointly managed by the Anglo American Corpora­tion of S.A. and the German company A.E.G. The chemical reaction converts common salt and nickel to nickel chloride and sodium during the charging phase.

  5. Inbreeding depression of sperm traits in the zebra finch Taeniopygia guttata

    Czech Academy of Sciences Publication Activity Database

    Opatová, Pavlína; Ihle, M.; Albrechtová, Jana; Tomášek, Oldřich; Kempenaers, B.; Forstmeier, W.; Albrecht, Tomáš

    2016-01-01

    Roč. 6, č. 1 (2016), s. 295-304 ISSN 2045-7758 R&D Projects: GA ČR(CZ) GAP506/12/2472 Institutional support: RVO:68081766 Keywords : gamete performance * genetic quality * sperm abnormality * sperm morphology * sperm velocity Subject RIV: EG - Zoology Impact factor: 2.440, year: 2016

  6. Proximate control of avian sex allocation : A study on zebra finches

    NARCIS (Netherlands)

    von Engelhardt, Nikolaus Benedikt

    2004-01-01

    Sex allocatie is de strategie van verschillende investering in mannelijke en vrouwelijke nakomelingen. Sex allocatie betreft zowel de investering in het relatieve aantal zoons en dochters, de geslachtsverhouding of sex ratio, als ook de relatieve investering in elke individuele zoon en dochter Zie:

  7. Human-like brain hemispheric dominance in birdsong learning.

    Science.gov (United States)

    Moorman, Sanne; Gobes, Sharon M H; Kuijpers, Maaike; Kerkhofs, Amber; Zandbergen, Matthijs A; Bolhuis, Johan J

    2012-07-31

    Unlike nonhuman primates, songbirds learn to vocalize very much like human infants acquire spoken language. In humans, Broca's area in the frontal lobe and Wernicke's area in the temporal lobe are crucially involved in speech production and perception, respectively. Songbirds have analogous brain regions that show a similar neural dissociation between vocal production and auditory perception and memory. In both humans and songbirds, there is evidence for lateralization of neural responsiveness in these brain regions. Human infants already show left-sided dominance in their brain activation when exposed to speech. Moreover, a memory-specific left-sided dominance in Wernicke's area for speech perception has been demonstrated in 2.5-mo-old babies. It is possible that auditory-vocal learning is associated with hemispheric dominance and that this association arose in songbirds and humans through convergent evolution. Therefore, we investigated whether there is similar song memory-related lateralization in the songbird brain. We exposed male zebra finches to tutor or unfamiliar song. We found left-sided dominance of neuronal activation in a Broca-like brain region (HVC, a letter-based name) of juvenile and adult zebra finch males, independent of the song stimulus presented. In addition, juvenile males showed left-sided dominance for tutor song but not for unfamiliar song in a Wernicke-like brain region (the caudomedial nidopallium). Thus, left-sided dominance in the caudomedial nidopallium was specific for the song-learning phase and was memory-related. These findings demonstrate a remarkable neural parallel between birdsong and human spoken language, and they have important consequences for our understanding of the evolution of auditory-vocal learning and its neural mechanisms.

  8. Reward and vocal production: song-associated place preference in songbirds.

    Science.gov (United States)

    Riters, Lauren V; Stevenson, Sharon A

    2012-05-15

    Vocal production is crucial for successful social interactions in multiple species. Reward can strongly influence behavior; however, the extent to which reward systems influence vocal behavior is unknown. In songbirds, singing occurs in different contexts. It can be spontaneous and undirected (e.g., song produced alone or as part of a large flock) or directed towards a conspecific (e.g., song used to attract a mate or influence a competitor). In this study, we developed a conditioned place preference paradigm to measure reward associated with different types of singing behavior in two songbird species. Both male zebra finches and European starlings developed a preference for a chamber associated with production of undirected song, suggesting that the production of undirected song is tightly coupled to intrinsic reward. In contrast, neither starlings nor zebra finches developed a place preference in association with directed song; however, male starlings singing directed song that failed to attract a female developed a place aversion. Unsuccessful contact calling behavior was also associated with a place aversion. These findings suggest that directed vocal behavior is not tightly linked to intrinsic reward but may be externally reinforced by social interactions. Data across two species thus support the hypothesis that the production of undirected but not directed song is tightly coupled to intrinsic reward. This study is the first to identify song-associated reward and suggests that reward associated with vocal production differs depending upon the context in which communication occurs. The findings have implications for understanding what motivates animals to engage in social behaviors and ways in which distinct reward mechanisms function to direct socially appropriate behaviors. Copyright © 2012 Elsevier Inc. All rights reserved.

  9. Neurons Responsive to Global Visual Motion Have Unique Tuning Properties in Hummingbirds.

    Science.gov (United States)

    Gaede, Andrea H; Goller, Benjamin; Lam, Jessica P M; Wylie, Douglas R; Altshuler, Douglas L

    2017-01-23

    Neurons in animal visual systems that respond to global optic flow exhibit selectivity for motion direction and/or velocity. The avian lentiformis mesencephali (LM), known in mammals as the nucleus of the optic tract (NOT), is a key nucleus for global motion processing [1-4]. In all animals tested, it has been found that the majority of LM and NOT neurons are tuned to temporo-nasal (back-to-front) motion [4-11]. Moreover, the monocular gain of the optokinetic response is higher in this direction, compared to naso-temporal (front-to-back) motion [12, 13]. Hummingbirds are sensitive to small visual perturbations while hovering, and they drift to compensate for optic flow in all directions [14]. Interestingly, the LM, but not other visual nuclei, is hypertrophied in hummingbirds relative to other birds [15], which suggests enhanced perception of global visual motion. Using extracellular recording techniques, we found that there is a uniform distribution of preferred directions in the LM in Anna's hummingbirds, whereas zebra finch and pigeon LM populations, as in other tetrapods, show a strong bias toward temporo-nasal motion. Furthermore, LM and NOT neurons are generally classified as tuned to "fast" or "slow" motion [10, 16, 17], and we predicted that most neurons would be tuned to slow visual motion as an adaptation for slow hovering. However, we found the opposite result: most hummingbird LM neurons are tuned to fast pattern velocities, compared to zebra finches and pigeons. Collectively, these results suggest a role in rapid responses during hovering, as well as in velocity control and collision avoidance during forward flight of hummingbirds. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. ASSESSING THE IMPACT OF CONTINUOUS BACTERIAL TREATMENTS OVER A TWO-WEEK PERIOD ON ZEBRA MUSSEL MORTALITY

    Energy Technology Data Exchange (ETDEWEB)

    Daniel P. Molloy

    2001-07-17

    These experiments indicated that in waters at 23 C the window of opportunity to kill zebra mussels with bacterial strain CL0145A is limited to the first two days of treatment. Treatments beyond two days will not increase mortality.

  11. The relationship between plants used to sustain finches (Fringillidae) and uses for human medicine in southeast Spain

    OpenAIRE

    Belda, Antonio; Peiro, Victoriano; Seva Román, Eduardo

    2012-01-01

    We analyzed plants that are traditionally used by wild bird hunters and breeders to capture and promote captive breeding of Fringillidae (finches or songbirds) in the province of Alicante, Spain. The majority of plants used in songbird breeding have medicinal properties in traditional human medicine (48 different uses); thus, another main goal was to show their relationships with human medical uses. We compiled a list of 97 plant species from 31 botanical families that are used to attract fin...

  12. Is there a link between shell morphology and parasites of zebra mussels?

    Science.gov (United States)

    Minguez, Laëtitia; Lang, Anne-Sophie; Beisel, Jean-Nicolas; Giambérini, Laure

    2012-02-01

    The shell morphology of zebra mussels, Dreissena polymorpha, was analyzed to determine if alterations in shell shape and asymmetry between valves were related to its infection status, i.e. infected or not by microparasites like ciliates Ophryoglena spp. or intracellular bacteria Rickettsiales-like organisms (RLOs), and by macroparasites like trematodes Phyllodistomum folium and Bucephalus polymorphus. For microparasites, two groups of mussels were observed depending on shell measurements. Mussels with the more concave shells were the most parasitized by ciliates. This could be more a consequence than a cause and we hypothesized that a modification of the water flow through the mantle cavity could promote the infection with a ciliate. There were more RLOs present in the most symmetrical individuals. A potential explanation involved a canalization of the left-right asymmetry as a by-product of the parasite infection. Trematode infections were associated with different responses in valve width. Females infected by P. folium displayed significantly higher symmetry in valve width compared with non-infected congeners, whereas the infection involved an opposite pattern in males. B. polymorphus was also linked to a decrease in valve width asymmetry. This study suggested that a relationship exists between parasitism and shell morphology through the physiological condition of host zebra mussels. Copyright © 2011 Elsevier Inc. All rights reserved.

  13. Efficacy of Pseudomonas fluorescens strain CL145A spray dried powder for controlling zebra mussels adhering to native unionid mussels within field enclosures

    Science.gov (United States)

    Luoma, James A.; Weber, Kerry L.; Severson, Todd J.; Mayer, Denise A.

    2015-01-01

    The efficacy of a commercially prepared spray dried powder (SDP) formulation of Pseudomonas fluorescens (strain CL145A) was evaluated for removing zebra mussels (Dreissena polymorpha) adhering to a population of unionid mussels in Lake Darling (Alexandria, Minnesota). Two groups of unionid mussels were used in the study. Unionid mussels were collected near the test area, weighed, photographed, individually tagged, and randomly allocated to one of nine test enclosures in equal proportions and then divided into two groups. The first group of unionid mussels (Group 1, n = 5 per test enclosure) were indiscriminately selected from each test enclosure and used to estimate the number of zebra mussels adhering to unionid mussels prior to exposure. The second group of unionid mussels (Group 2, n = 22 per test enclosure) were used to evaluate the efficacy of SDP for removal of adhering zebra mussels. Both Group 1 and Group 2 mussels were used to evaluate the effects of SDP exposure on unionid mussel survival.

  14. Seasonal abundances of naked amoebae in biofilms on shells of zebra mussels (Dreissena polymorpha) with comparative data from rock scrapings.

    Science.gov (United States)

    Bischoff, Paul J; Wetmore, Scott

    2009-01-01

    In North America, zebra mussels (Dreissena polymorpha) are notoriously known as invasive species. The abundance of naked amoebae sampled from the shells of zebra mussels was compared with abundances from rock scrapings at approximately monthly intervals for 1 year. The sites were 2 km apart along the same shoreline. No significant difference in abundance of naked amoebae (F = 1.44; P

  15. Plains zebra (Equus quagga) adrenocortical activity increases during times of large aggregations in the Serengeti ecosystem.

    Science.gov (United States)

    Seeber, P A; Franz, M; Dehnhard, M; Ganswindt, A; Greenwood, A D; East, M L

    2018-04-20

    Adverse environmental stimuli (stressors) activate the hypothalamic-pituitary-adrenal axis and contribute to allostatic load. This study investigates the contribution of environmental stressors and life history stage to allostatic load in a migratory population of plains zebras (Equus quagga) in the Serengeti ecosystem, in Tanzania, which experiences large local variations in aggregation. We expected higher fGCM response to the environmental stressors of feeding competition, predation pressure and unpredictable social relationships in larger than in smaller aggregations, and in animals at energetically costly life history stages. As the study was conducted during the 2016 El Niño, we did not expect food quality of forage or a lack of water to strongly affect fGCM responses in the dry season. We measured fecal glucocorticoid metabolite (fGCM) concentrations using an enzyme immunoassay (EIA) targeting 11β-hydroxyetiocholanolone and validated its reliability in captive plains zebras. Our results revealed significantly higher fGCM concentrations 1) in large aggregations than in smaller groupings, and 2) in band stallions than in bachelor males. Concentrations of fGCM were not significantly higher in females at the energetically costly life stage of late pregnancy/lactation. The higher allostatic load of stallions associated with females, than bachelor males is likely caused by social stressors. In conclusion, migratory zebras have elevated allostatic loads in large aggregations that probably result from their combined responses to increased feeding competition, predation pressure and various social stressors. Further research is required to disentangle the contribution of these stressors to allostatic load in migratory populations. Copyright © 2018 Elsevier Inc. All rights reserved.

  16. TLD gamma-ray energy deposition measurements in the zero energy fast reactor ZEBRA

    International Nuclear Information System (INIS)

    Knipe, A.D.

    1977-01-01

    A recent study of gamma-ray energy deposition was carried out in the Zebra reactor at AEE Winfrith during a collaborative programme between the UKAEA and PNC of Japan. The programme was given the title MOZART. This paper describes the TLD experiments in the MOZART MZB assembly and discusses the technique and various corrections necessary to relate the measured quantity to the calculated energy deposition

  17. Molecular Cloning and Functional Characterization of Mannose Receptor in Zebra Fish (Danio rerio during Infection with Aeromonas sobria

    Directory of Open Access Journals (Sweden)

    Feifei Zheng

    2015-05-01

    Full Text Available Mannose receptor (MR is a member of pattern-recognition receptors (PRRs, which plays a significant role in immunity responses. Much work on MR has been done in mammals and birds while little in fish. In this report, a MR gene (designated as zfMR was cloned from zebra fish (Danio rerio, which is an attractive model for the studies of animal diseases. The full-length cDNA of zfMR contains 6248 bp encoding a putative protein of 1428 amino acids. The predicted amino acid sequences showed that zfMR contained a cysteine-rich domain, a single fibronectin type II (FN II domain, eight C-type lectin-like domains (CTLDs, a transmembrane domain and a short C-terminal cytoplasmic domain, sharing highly conserved structures with MRs from the other species. The MR mRNA could be detected in all examined tissues with highest level in kidney. The temporal expression patterns of MR, IL-1β and TNF-α mRNAs were analyzed in the liver, spleen, kidney and intestine post of infection with Aeromonas sobria. By immunohistochemistry assay, slight enhancement of MR protein was also observed in the spleen and intestine of the infected zebra fish. The established zebra fish-A. sobria infection model will be valuable for elucidating the role of MR in fish immune responses to infection.

  18. Examining the role of tuber biochemistry in the development of zebra chip in stored potato tubers

    Science.gov (United States)

    Zebra chip disease (ZC), associated with infection by the bacterium ‘Candidatus Liberibacter solanacearum’ (Lso), is an emerging problem for potato growers in the United States, Mexico, and New Zealand. Although potato tubers exhibiting ZC symptoms will be rejected by processors, it remains possible...

  19. Genotoxic effects induced by the exposure to an environmental mixture of illicit drugs to the zebra mussel.

    Science.gov (United States)

    Parolini, Marco; Magni, Stefano; Castiglioni, Sara; Binelli, Andrea

    2016-10-01

    Despite the growing interest on the presence of illicit drugs in freshwater ecosystems, just recently the attention has been focused on their potential toxicity towards non-target aquatic species. However, these studies largely neglected the effects induced by exposure to complex mixtures of illicit drugs, which could be different compared to those caused by single psychoactive molecules. This study was aimed at investigating the genetic damage induced by a 14-day exposure to a realistic mixture of the most common illicit drugs found in surface waters worldwide (cocaine, benzoylecgonine, amphetamine, morphine and 3,4-methylenedioxymethamphetamine) on the zebra mussel (Dreissena polymorpha). The mixture caused a significant increase of DNA fragmentation and triggered the apoptotic process and micronuclei formation in zebra mussel hemocytes, pointing out its potential genotoxicity towards this bivalve species. Copyright © 2016 Elsevier Inc. All rights reserved.

  20. Environmental impact on faecal glucocorticoid metabolite concentrations in Grevy's Zebra (Equus grevyi)

    OpenAIRE

    Yarnell, K; Walker, SL

    2017-01-01

    The non-invasive nature of faecal glucocorticoid metabolite (FGM) assessment means that sample collection is on an opportunistic basis and samples cannot always be collected immediately upon defection during field studies. Faeces that have been exposed to heat and moisturemay not accurately reflect levels of FGM. Our study exposed male (n=3) and female (n=3) Grevy's zebra (Equus grevyi) faeces to six environmental conditions to simulate a range of weather and seasonal patterns (temperate clim...

  1. Systemic infection by equid herpesvirus-1 in a Grevy's zebra stallion (Equus grevyi) with particular reference to genital pathology.

    Science.gov (United States)

    Blunden, A S; Smith, K C; Whitwell, K E; Dunn, K A

    1998-11-01

    A severe multi-systemic form of equid herpesvirus-1 infection is described in an adult zebra stallion. There was multifocal necrotizing rhinitis, marked hydrothorax and pulmonary oedema, with viral antigen expression in degenerating epithelial cells, local endothelial cells and intravascular leucocytes of the nasal mucosa and lung. Specific localization of EHV-1 infection was seen in the testes and epididymides, including infection of Leydig cells and germinal epithelium, which would have facilitated venereal shedding of virus in life. The case provided a unique opportunity to study hitherto undescribed aspects of the pathogenesis of naturally occurring EHV-1 infection in the male equine genital tract. Restriction digests of the isolate demonstrated a pattern similar to that of EHV-1 isolates previously recovered from aborted zebra and onager fetuses.

  2. Comparative morphology of zebra (Dreissena polymorpha) and quagga (Dreissena bugensis) mussel sperm: Light and electron microscopy

    Science.gov (United States)

    Walker, G.K.; Black, M.G.; Edwards, C.A.

    1996-01-01

    Adult zebra (Dreissena polymorpha) and quagga (Dreissena bugensis) mussels were induced to release large quantities of live spermatozoa by the administration of 5-hydroxytryptamine (serotonin). Sperm were photographed alive using phase-contrast microscopy and were fixed subsequently with glutaraldehyde followed by osmium tetroxide for eventual examination by transmission or scanning electron microscopy. The sperm of both genera are of the ect-aquasperm type. Their overall dimensions and shape allow for easy discrimination at the light and scanning electron microscopy level. Transmission electron microscopy of the cells reveals a barrel-shaped nucleus in zebra mussel sperm and an elongated nucleus in quagga mussel sperm. In both species, an acrosome is cradled in a nuclear fossa. The ultrastructure of the acrosome and axial body, however, is distinctive for each species. The structures of the midpiece are shown, including a unique mitochondrial "skirt" that includes densely packed parallel cristae and extends in a narrow sheet from the mitochondria.

  3. Bioavailability of particulate metal to zebra mussels: biodynamic modelling shows that assimilation efficiencies are site-specific.

    Science.gov (United States)

    Bourgeault, Adeline; Gourlay-Francé, Catherine; Priadi, Cindy; Ayrault, Sophie; Tusseau-Vuillemin, Marie-Hélène

    2011-12-01

    This study investigates the ability of the biodynamic model to predict the trophic bioaccumulation of cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni) and zinc (Zn) in a freshwater bivalve. Zebra mussels were transplanted to three sites along the Seine River (France) and collected monthly for 11 months. Measurements of the metal body burdens in mussels were compared with the predictions from the biodynamic model. The exchangeable fraction of metal particles did not account for the bioavailability of particulate metals, since it did not capture the differences between sites. The assimilation efficiency (AE) parameter is necessary to take into account biotic factors influencing particulate metal bioavailability. The biodynamic model, applied with AEs from the literature, overestimated the measured concentrations in zebra mussels, the extent of overestimation being site-specific. Therefore, an original methodology was proposed for in situ AE measurements for each site and metal. Copyright © 2011 Elsevier Ltd. All rights reserved.

  4. Recent results of zebra patterns in solar radio bursts

    International Nuclear Information System (INIS)

    Chernov, Gennady P.

    2010-01-01

    This review covers the most recent experimental results and theoretical research on zebra patterns (ZPs) in solar radio bursts. The basic attention is given to events with new peculiar elements of zebra patterns received over the last few years. All new properties are considered in light of both what was known earlier and new theoretical models. Large-scale ZPs consisting of small-scale fiber bursts could be explained by simultaneous inclusion of two mechanisms when whistler waves 'highlight' the levels of double plasma resonance (DPR). A unique fine structure was observed in the event on 2006 December 13: spikes in absorption formed dark ZP stripes against the absorptive type III-like bursts. The spikes in absorption can appear in accordance with well known mechanisms of absorptive bursts. The additional injection of fast particles filled the loss-cone (breaking the loss-cone distribution), and the generation of the continuum was quenched at these moments. The maximum absorptive effect occurs at the DPR levels. The parameters of millisecond spikes are determined by small dimensions of the particle beams and local scale heights in the radio source. Thus, the DPR model helps to understand several aspects of unusual elements of ZPs. However, the simultaneous existence of several tens of the DPR levels in the corona is impossible for any realistic profile of the plasma density and magnetic field. Three new theories of ZPs are examined. The formation of eigenmodes of transparency and opacity during the propagation of radio waves through regular coronal inhomogeneities is the most natural and promising mechanism. Two other models (nonlinear periodic space - charge waves and scattering of fast protons on ion-sound harmonics) could happen in large radio bursts. (invited reviews)

  5. Association of promising germplasm exhibiting tolerance to psyllids, aphids, and zebra chip disease with foliar host chemistry

    Science.gov (United States)

    Long term, sustainable management of zebra chip disease of potato, caused by “Candidatus Liberibacter solanacearum” (Lso) and vectored by potato psyllids (Bactericera cockerelli Sulc), will require development of new cultivars resistant or tolerant to infection and/or capable of reducing spread. The...

  6. Doppler coefficient measurements in Zebra Core 5

    International Nuclear Information System (INIS)

    Baker, A.R.; Wheeler, R.C.

    1965-11-01

    Measurements using a central hot loop in Zebra Core 5 are described. Results are given for the Doppler coefficients found in a number of assemblies with PuO 2 and 16% PuO 2 /84% depleted UO 2 pins, loaded with different combinations of steel, sodium or void pins. The mixed oxide results are in general about 20% more negative than was calculated using the FD2 data set, but agreement is good if the plutonium contributions in the calculations are omitted. The small positive Doppler coefficient calculated for Pu239 was not observed, and two measurements indicated instead a small negative effect. The Doppler effect in the mixed oxide systems was found to vary approximately as 1/T. The results from the empty loop and non-fissile assemblies indicate either a small negative Doppler effect in steel or alternatively the presence of an unexplained expansion effect. (author)

  7. IMPACT OF OXYGEN CONCENTRATION ON ZEBRA MUSSEL MORTALITY

    Energy Technology Data Exchange (ETDEWEB)

    Daniel P. Molloy

    2003-01-27

    These tests have indicated that the bacterium Pseudomonas fluorescens strain CL0145A is effective at killing zebra mussels in environments having dissolved oxygen (DO) concentrations ranging from very low to very high. The results suggest that the highest mussel kill can be achieved in moderately to highly aerated environments, while kill may be 0-20% lower under conditions of very low oxygen. For example, under highly oxygenated conditions 97% kill was achieved while conditions having low DO produced 79% mussel kill. Service water measured in a local power plant indicated that DO concentrations were in the range of 8-9 ppm (e.g., highly aerated) within their pipes. Therefore, we will not expect to see decreases in the efficacy of CL0145A treatments due to oxygen levels within such power plant pipes.

  8. IMPACT OF OXYGEN CONCENTRATION ON ZEBRA MUSSEL MORTALITY

    International Nuclear Information System (INIS)

    Molloy, Daniel P.

    2003-01-01

    These tests have indicated that the bacterium Pseudomonas fluorescens strain CL0145A is effective at killing zebra mussels in environments having dissolved oxygen (DO) concentrations ranging from very low to very high. The results suggest that the highest mussel kill can be achieved in moderately to highly aerated environments, while kill may be 0-20% lower under conditions of very low oxygen. For example, under highly oxygenated conditions 97% kill was achieved while conditions having low DO produced 79% mussel kill. Service water measured in a local power plant indicated that DO concentrations were in the range of 8-9 ppm (e.g., highly aerated) within their pipes. Therefore, we will not expect to see decreases in the efficacy of CL0145A treatments due to oxygen levels within such power plant pipes

  9. Differences in metal sequestration between zebra mussels from clean and polluted field locations.

    Science.gov (United States)

    Voets, Judith; Redeker, Erik Steen; Blust, Ronny; Bervoets, Lieven

    2009-06-04

    Organisms are able to detoxify accumulated metals by, e.g. binding them to metallothionein (MT) and/or sequestering them in metal-rich granules (MRG). The different factors involved in determining the capacity or efficiency with which metals are detoxified are not yet known. In this work we studied how the sub-cellular distribution pattern of cadmium, copper and zinc in whole tissue of zebra mussels from clean and polluted surface waters is influenced by the total accumulated metal concentration and by its physiological condition. Additionally we measured the metallothionein concentration in the mussel tissue. Metal concentration increased gradually in the metal-sensitive and detoxified sub-cellular fractions with increasing whole tissue concentrations. However, metal concentrations in the sensitive fractions did not increase to the same extent as metal concentrations in whole tissues. In more polluted mussels the contribution of MRG and MT became more important. Nevertheless, metal detoxification was not sufficient to prevent metal binding to heat-sensitive low molecular weight proteins (HDP fraction). Finally we found an indication that metal detoxification was influenced by the condition of the zebra mussels. MT content could be explained for up to 83% by variations in Zn concentration and physiological condition of the mussels.

  10. Differences in metal sequestration between zebra mussels from clean and polluted field locations

    International Nuclear Information System (INIS)

    Voets, Judith; Redeker, Erik Steen; Blust, Ronny; Bervoets, Lieven

    2009-01-01

    Organisms are able to detoxify accumulated metals by, e.g. binding them to metallothionein (MT) and/or sequestering them in metal-rich granules (MRG). The different factors involved in determining the capacity or efficiency with which metals are detoxified are not yet known. In this work we studied how the sub-cellular distribution pattern of cadmium, copper and zinc in whole tissue of zebra mussels from clean and polluted surface waters is influenced by the total accumulated metal concentration and by its physiological condition. Additionally we measured the metallothionein concentration in the mussel tissue. Metal concentration increased gradually in the metal-sensitive and detoxified sub-cellular fractions with increasing whole tissue concentrations. However, metal concentrations in the sensitive fractions did not increase to the same extent as metal concentrations in whole tissues. In more polluted mussels the contribution of MRG and MT became more important. Nevertheless, metal detoxification was not sufficient to prevent metal binding to heat-sensitive low molecular weight proteins (HDP fraction). Finally we found an indication that metal detoxification was influenced by the condition of the zebra mussels. MT content could be explained for up to 83% by variations in Zn concentration and physiological condition of the mussels.

  11. Differences in metal sequestration between zebra mussels from clean and polluted field locations

    Energy Technology Data Exchange (ETDEWEB)

    Voets, Judith [Laboratory for Ecophysiology, Biochemistry and Toxicology, Department of Biology, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp (Belgium); Redeker, Erik Steen [Laboratory for Ecophysiology, Biochemistry and Toxicology, Department of Biology, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp (Belgium); Institute for Materials Research, Chemistry Division, Hasselt University, Agoralaan Building D G1-36, B 3590 Diepenbeek (Belgium); Blust, Ronny [Laboratory for Ecophysiology, Biochemistry and Toxicology, Department of Biology, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp (Belgium); Bervoets, Lieven, E-mail: Lieven.bervoets@ua.ac.be [Laboratory for Ecophysiology, Biochemistry and Toxicology, Department of Biology, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp (Belgium)

    2009-06-04

    Organisms are able to detoxify accumulated metals by, e.g. binding them to metallothionein (MT) and/or sequestering them in metal-rich granules (MRG). The different factors involved in determining the capacity or efficiency with which metals are detoxified are not yet known. In this work we studied how the sub-cellular distribution pattern of cadmium, copper and zinc in whole tissue of zebra mussels from clean and polluted surface waters is influenced by the total accumulated metal concentration and by its physiological condition. Additionally we measured the metallothionein concentration in the mussel tissue. Metal concentration increased gradually in the metal-sensitive and detoxified sub-cellular fractions with increasing whole tissue concentrations. However, metal concentrations in the sensitive fractions did not increase to the same extent as metal concentrations in whole tissues. In more polluted mussels the contribution of MRG and MT became more important. Nevertheless, metal detoxification was not sufficient to prevent metal binding to heat-sensitive low molecular weight proteins (HDP fraction). Finally we found an indication that metal detoxification was influenced by the condition of the zebra mussels. MT content could be explained for up to 83% by variations in Zn concentration and physiological condition of the mussels.

  12. Transplanted zebra mussels (Dreissena polymorpha) as active biomonitors in an effluent-dominated river.

    Science.gov (United States)

    Smolders, Roel; Bervoets, Lieven; Blust, Ronny

    2002-09-01

    For over 20 years, mussels have been recommended as one of the most suitable biomonitoring organisms for aquatic ecosystems. Though the common mussel (Mytilus edulis) is frequently used for biomonitoring estuarine and marine ecosystems, no freshwater species is promoted for similar monitoring networks. Recently, however, the zebra mussel (Dreissena polymorpha) has been proposed as a suitable monitoring organism in freshwater ecosystems. The aim of this study was to explore the usefulness of transplanted zebra mussels as active biomonitors in an effluent-dominated stream. Results showed that for these purposes, an exposure period of at least a few weeks is required to detect any significant changes in condition status or scope for growth. Wet-tissue-weight:dry-tissue-weight ratio was the most sensitive measure to quantify effects of field exposure on physiological fitness. In case of scope for growth (SfG), energy intake was the factor determining the overall energy budget of the mussels. Based on the dilution rates of the two different effluents present, effluent 2 had the most important effect on the condition status of the exposed organisms. Overall, we conclude that the use of transplanted mussels is a sensitive and easily applicable active biomonitor that can be used to assess water quality, pollution, and subsequent recovery through self-purification in field situations.

  13. Variations in zebra mussel (Dreissena polymorpha) veliger densities throughout 1996 at Dam 52 on the lower Ohio River

    Science.gov (United States)

    Reed, Darren P.; Herod, Jeffrey J.; Sickel, James B.

    1998-01-01

    Zebra mussel veliger densities were monitored throughout 1996 at Lock and Dam 52 on the lower Ohio River near Brookport, IL. The spawning season occurred between mid June and early September with veliger densities peaking at 30,000/m3 in late June. Veliger first appeared at a water temperature of 21° C. When spawning ended in September the water temperature was 22 °C. Veligers were found throughout November when the water temperature was 10 °C. The lowest temperature at which veligers were observed was 7 ° C in March 1996. These results show that the zebra mussels in the lower Ohio River are reproducing naturally and that spawning appears to be synchronous. The presence of larvae at low temperatures in March suggests that veligers are capable of delaying settlement and overwintering in the planktonic stage.

  14. Characterizing zebra chip symptom severity and identifying spectral signatures associated with 'Candidatus Liberibacter solanacearum' infected potato tubers

    Science.gov (United States)

    Zebra chip (ZC) is a disease of potatoes, which is associated with the bacteria ‘Candidatus Liberibacter solanacearum’ (Lso). Lso is transmitted by the potato psyllid, Bactericera cockerelli (Šulc) (Hemiptera: Triozidae). ZC reduces yield and quality, as it results in discoloration of the vascular ...

  15. Undirected (solitary birdsong in female and male blue-capped cordon-bleus (Uraeginthus cyanocephalus and its endocrine correlates.

    Directory of Open Access Journals (Sweden)

    Nicole Geberzahn

    Full Text Available BACKGROUND: Birdsong is a popular model system in research areas such as vocal communication, neuroethology or neuroendocrinology of behaviour. As most research has been conducted on species with male-only song production, the hormone-dependency of male song is well established. However, female singing and its mechanisms are poorly understood. METHODOLOGY/PRINCIPAL FINDINGS: We characterised the song and its endocrine correlates of blue-capped cordon-bleus (Uraeginthus cyanocephalus, a species in which both sexes sing. Like other estrildids, they produce directed song during courtship and undirected (or solitary song in isolation, i.e. when the mate is not visible or absent. We compare solitary song of blue-capped cordon-bleus to published descriptions of the song of its relative, the zebra finch (Taeniopygia guttata. Solitary song of cordon-bleus shared some overall song features with that of zebra finches but differed in spectro-temporal song features, sequential stereotypy and sequential organisation. The song of cordon-bleus was dimorphic with respect to the larger size of syllable repertoires, the higher song duration and the lower variability of pitch goodness (measuring the pureness of harmonic sounds in males. However, in both sexes the overall plasma testosterone concentrations were low (ca. 300 pg/ml and did not correlate with the sexually dimorphic song motor pattern. Despite such low concentrations, the increase in the rate of solitary song coincided with an increase in the level of testosterone. Furthermore, the latency to start singing after the separation from the mate was related to hormone levels. CONCLUSIONS/SIGNIFICANCE: Our findings suggest that the occurrence of solitary song but not its motor pattern might be under the control of testosterone in female and male cordon-bleus.

  16. At the interface of the auditory and vocal motor systems: NIf and its role in vocal processing, production and learning.

    Science.gov (United States)

    Lewandowski, Brian; Vyssotski, Alexei; Hahnloser, Richard H R; Schmidt, Marc

    2013-06-01

    Communication between auditory and vocal motor nuclei is essential for vocal learning. In songbirds, the nucleus interfacialis of the nidopallium (NIf) is part of a sensorimotor loop, along with auditory nucleus avalanche (Av) and song system nucleus HVC, that links the auditory and song systems. Most of the auditory information comes through this sensorimotor loop, with the projection from NIf to HVC representing the largest single source of auditory information to the song system. In addition to providing the majority of HVC's auditory input, NIf is also the primary driver of spontaneous activity and premotor-like bursting during sleep in HVC. Like HVC and RA, two nuclei critical for song learning and production, NIf exhibits behavioral-state dependent auditory responses and strong motor bursts that precede song output. NIf also exhibits extended periods of fast gamma oscillations following vocal production. Based on the converging evidence from studies of physiology and functional connectivity it would be reasonable to expect NIf to play an important role in the learning, maintenance, and production of song. Surprisingly, however, lesions of NIf in adult zebra finches have no effect on song production or maintenance. Only the plastic song produced by juvenile zebra finches during the sensorimotor phase of song learning is affected by NIf lesions. In this review, we carefully examine what is known about NIf at the anatomical, physiological, and behavioral levels. We reexamine conclusions drawn from previous studies in the light of our current understanding of the song system, and establish what can be said with certainty about NIf's involvement in song learning, maintenance, and production. Finally, we review recent theories of song learning integrating possible roles for NIf within these frameworks and suggest possible parallels between NIf and sensorimotor areas that form part of the neural circuitry for speech processing in humans. Copyright © 2013 Elsevier

  17. Sex differences in the representation of call stimuli in a songbird secondary auditory area.

    Science.gov (United States)

    Giret, Nicolas; Menardy, Fabien; Del Negro, Catherine

    2015-01-01

    Understanding how communication sounds are encoded in the central auditory system is critical to deciphering the neural bases of acoustic communication. Songbirds use learned or unlearned vocalizations in a variety of social interactions. They have telencephalic auditory areas specialized for processing natural sounds and considered as playing a critical role in the discrimination of behaviorally relevant vocal sounds. The zebra finch, a highly social songbird species, forms lifelong pair bonds. Only male zebra finches sing. However, both sexes produce the distance call when placed in visual isolation. This call is sexually dimorphic, is learned only in males and provides support for individual recognition in both sexes. Here, we assessed whether auditory processing of distance calls differs between paired males and females by recording spiking activity in a secondary auditory area, the caudolateral mesopallium (CLM), while presenting the distance calls of a variety of individuals, including the bird itself, the mate, familiar and unfamiliar males and females. In males, the CLM is potentially involved in auditory feedback processing important for vocal learning. Based on both the analyses of spike rates and temporal aspects of discharges, our results clearly indicate that call-evoked responses of CLM neurons are sexually dimorphic, being stronger, lasting longer, and conveying more information about calls in males than in females. In addition, how auditory responses vary among call types differ between sexes. In females, response strength differs between familiar male and female calls. In males, temporal features of responses reveal a sensitivity to the bird's own call. These findings provide evidence that sexual dimorphism occurs in higher-order processing areas within the auditory system. They suggest a sexual dimorphism in the function of the CLM, contributing to transmit information about the self-generated calls in males and to storage of information about the

  18. Sex differences in the representation of call stimuli in a songbird secondary auditory area

    Directory of Open Access Journals (Sweden)

    Nicolas eGiret

    2015-10-01

    Full Text Available Understanding how communication sounds are encoded in the central auditory system is critical to deciphering the neural bases of acoustic communication. Songbirds use learned or unlearned vocalizations in a variety of social interactions. They have telencephalic auditory areas specialized for processing natural sounds and considered as playing a critical role in the discrimination of behaviorally relevant vocal sounds. The zebra finch, a highly social songbird species, forms lifelong pair bonds. Only male zebra finches sing. However, both sexes produce the distance call when placed in visual isolation. This call is sexually dimorphic, is learned only in males and provides support for individual recognition in both sexes. Here, we assessed whether auditory processing of distance calls differs between paired males and females by recording spiking activity in a secondary auditory area, the caudolateral mesopallium (CLM, while presenting the distance calls of a variety of individuals, including the bird itself, the mate, familiar and unfamiliar males and females. In males, the CLM is potentially involved in auditory feedback processing important for vocal learning. Based on both the analyses of spike rates and temporal aspects of discharges, our results clearly indicate that call-evoked responses of CLM neurons are sexually dimorphic, being stronger, lasting longer and conveying more information about calls in males than in females. In addition, how auditory responses vary among call types differ between sexes. In females, response strength differs between familiar male and female calls. In males, temporal features of responses reveal a sensitivity to the bird’s own call. These findings provide evidence that sexual dimorphism occurs in higher-order processing areas within the auditory system. They suggest a sexual dimorphism in the function of the CLM, contributing to transmit information about the self-generated calls in males and to storage of

  19. Spatio-temporal spawning and larval dynamics of a zebra mussel (Dreissena polymorpha) population in a North Texas Reservoir: implications for invasions in the southern United States

    Science.gov (United States)

    Churchill, Christopher John

    2013-01-01

    Zebra mussels were first observed in Texas in 2009 in a reservoir (Lake Texoma) on the Texas-Oklahoma border. In 2012, an established population was found in a near-by reservoir, Ray Roberts Lake, and in June 2013, settled mussels were detected in a third north Texas reservoir, Lake Lewisville. An established population was detected in Belton Lake in September 2013. With the exception of Louisiana, these occurrences in Texas mark the current southern extent of the range of this species in the United States. Previous studies indicate that zebra mussel populations could be affected by environmental conditions, especially increased temperatures and extreme droughts, which are characteristic of surface waters of the southern and southwestern United States. Data collected during the first three years (2010–12) of a long-term monitoring program were analyzed to determine if spatio-temporal zebra mussel spawning and larval dynamics were related to physicochemical water properties in Lake Texoma. Reproductive output of the local population was significantly related to water temperature and lake elevation. Estimated mean date of first spawn in Lake Texoma was approximately 1.5 months earlier and peak veliger densities were observed two months earlier than in Lake Erie. Annual maximum veliger density declined significantly during the study period (p mussels in littoral zones. Veliger spatial distributions were associated with physicochemical stratification characteristics. Veligers were observed in the deepest oxygenated water after lake stratification, which occurred in late spring. Results of this study indicate environmental conditions can influence variability of population sizes and spatial distributions of zebra mussels along the current southern frontier of their geographic range. Although the future population size trajectory and geographic range are uncertain, increased temperatures and intermittent, extreme droughts likely will affect spatio-temporal dynamics of

  20. The evolution of sexual size dimorphism in the house finch. V. Maternal effects.

    Science.gov (United States)

    Badyaev, Alexander V; Beck, Michelle L; Hill, Geoffrey E; Whittingham, Linda A

    2003-02-01

    The phenotype of a mother and the environment that she provides might differentially affect the phenotypes of her sons and daughters, leading to change in sexual size dimorphism. Whereas these maternal effects should evolve to accommodate the adaptations of both the maternal and offspring generations, the mechanisms by which this is accomplished are rarely known. In birds, females adjust the onset of incubation (coincident with the first egg or after all eggs are laid) in response to the environment during breeding, and thus, indirectly, determine the duration of offspring growth. In the two house finch (Carpodacus mexicanus) populations that breed at the extremes of the species' distribution (Montana and Alabama), females experience highly distinct climatic conditions during nesting. We show that in close association with these conditions, females adjusted jointly the onset of incubation and the sequence in which they produced male and female eggs and consequently modified the growth of sons and daughters. The onset of incubation in newly breeding females closely tracked ambient temperature in a pattern consistent with the maintenance of egg viability. Because of the very different climates in Montana and Alabama, females in these populations showed the opposite patterns of seasonal change in incubation onset and the opposite sex bias in egg-laying order. In females with breeding experience, incubation onset and sex bias in laying order were closely linked regardless of the climatic variation. In nests in which incubation began with the onset of egg laying, the first-laid eggs were mostly females in Montana, but mostly males in Alabama. Because in both populations, male, but not female, embryos grew faster when exposed to longer incubation, the sex-bias produced highly divergent sizes of male and female juveniles between the populations. Overall, the compensatory interaction between the onset of incubation and the sex-biased laying order achieved a compromise

  1. Pathology and immunohistochemistry of papillomavirus-associated cutaneous lesions in Cape mountain zebra, giraffe, sable antelope and African buffalo in South Africa

    Directory of Open Access Journals (Sweden)

    J. H. Williams

    2011-04-01

    Full Text Available Skin lesions associated with papillomaviruses have been reported in many animal species and man. Bovine papillomavirus (BVP affects mainly the epidermis, but also the dermis in several species including bovine, the best-known example being equine sarcoid, which is associated with BVP types 1 and 2. This publication describes and illustrates the macroscopic and histological appearance of BPV-associated papillomatous, fibropapillomatous or sarcoid-like lesions in Cape mountain zebra (Equus zebra zebra from the Gariep Dam Nature Reserve, 2 giraffes (Giraffa camelopardalis from the Kruger National Park, and a sable antelope (Hippotragus niger from the Kimberley area of South Africa. An African buffalo (Syncerus caffer cow from Kruger National Park also had papillomatous lesions but molecular characterisation of lesional virus was not done. Immunohistochemical staining using polyclonal rabbit antiserum to chemically disrupted BPV-1, which cross-reacts with the L1 capsid of most known papillomaviruses, was positive in cells of the stratum granulosum of lesions in Giraffe 1, the sable and the buffalo and negative in those of the zebra and Giraffe 2. Fibropapillomatous and sarcoid-like lesions from an adult bovine were used as positive control for the immunohistochemistry and are described and the immunohistochemistry illustrated for comparison. Macroscopically, both adult female giraffe had severely thickened multifocal to coalescing nodular and occasionally ulcerated lesions of the head, neck and trunk with local poorly-circumscribed invasion into the subcutis. Necropsy performed on the 2nd giraffe revealed neither internal metastases nor serious underlying disease. Giraffe 1 had scattered, and Giraffe 2 numerous, large, anaplastic, at times indistinctly multinucleated dermal fibroblasts with bizarre nuclei within the sarcoid-like lesions, which were BPV-1 positive in Giraffe 1 and BPV-1 and -2 positive in Giraffe 2 by RT-PCR. The sable antelope

  2. Use of zebra mussel (dreissena polymorpha) to assess trace metals in river water

    International Nuclear Information System (INIS)

    Anzano, J.; Lasheras, R.J.; Bonilla, A.; Anwar, J.

    2007-01-01

    Ebro river (Spain) has been fairly contaminated by industrial effluents: The toxicity level of the river due to heavy metals has been monitored by analyzing zebra mussels (Dreissena Polymorpha) samples as bioindicator. To access the level of toxicity ten metals (AI, Cd, Cr, Cu, Fe, Ni, Pb, Se, Sn and Zn) were determined by Voltamperometry. The conditions of determination were optimized for each metal prior to determination. Aqueous solutions of metals concerned were used as standards in detenpinations. (author)

  3. Underwater cleaning techniqued used for removal of zebra mussels at the FitzPatrick Nuclear Power Plant

    International Nuclear Information System (INIS)

    Hobbs, B.; Kahabka, J.

    1995-01-01

    This paper discusses the use of a mechanical brush cleaning technology recently used to remove biofouling from the Circulating Water (CW) System at New York Power Authority's James A. FitzPatrick Nuclear Power Plant. The FitzPatrick plant had previously used chemical molluscicide to treat zebra mussels in the CW system. Full system treatment was performed in 1992 with limited forebay/screenwell treatment in 1993. The New York Power Authority (NYPA) decided to conduct a mechanical cleaning of the intake system in 1994. Specific project objectives included: (1) Achieve a level of surface cleaniness greater than 98%; (2) Remove 100% of debris, both existing sediment and debris generated as a result of cleaning; (3) Inspect all surfaces and components, identifying any problem areas; (4) Complete the task in a time frame within the 1994-95 refueling outage schedule window, and; (5) Determine if underwater mechanical cleaning is a cost-effective zebra mussel control method suitable for future application at FitzPatrick. A pre-cleaning inspection, including underwater video photography, was conducted of each area. Cleaning was accomplished using diver-controlled, multi-brush equipment included the electro-hydraulic powered Submersible Cleaning and Maintenance Platform (SCAMP), and several designs of hand-held machines. The brushes swept all zebra mussels off surfaces, restoring concrete and metal substrates to their original condition. Sensitive areas including pump housings, standpipes, sensor piping and chlorine injection tubing, were cleaned without degradation. Submersible vortex vacuum pumps were used to remove debris from the cavity. More than 46,000 ft 2 of surface area was cleaned and over 460 cubic yards of dewatered debris were removed. As each area was completed, a post-clean inspection with photos and video was performed

  4. Book review: Biology and management of invasive quagga and zebra mussels in the western United States

    Science.gov (United States)

    Benson, Amy J.

    2017-01-01

    Water is a precious and limited commodity in the western United States and its conveyance is extremely important. Therefore, it is critical to do as much as possible to prevent the spread of two species of dreissenid mussels, both non-native and highly invasive aquatic species already well-established in the eastern half of the United States. This book addresses the occurrences of the two dreissenid mussels in the West, the quagga mussel and the zebra mussel, that are both known to negatively impact water delivery systems and natural ecosystems. It is edited by two researchers whom have extensive experience working with the mussels in the West and is composed of 34 chapters, or articles, written by a variety of experts.Book information: Biology and Management of Invasive Quagga and Zebra Mussels in the Western United States. Edited by Wai Hing Wong and Shawn L. Gerstenberger. Boca Raton (Florida): CRC Press (Taylor & Francis Group). $149.95. xx + 545 p.; ill.; index. ISBN: 978-1-4665-9561-3. [Compact Disc included.] 2015.

  5. Ecological impact assessment of sediment remediation in a metal-contaminated lowland river using translocated zebra mussels and resident macroinvertebrates

    International Nuclear Information System (INIS)

    De Jonge, M.; Belpaire, C.; Geeraerts, C.; De Cooman, W.; Blust, R.; Bervoets, L.

    2012-01-01

    The present study investigated to what extent accumulated metal levels in aquatic invertebrates can reflect environmental contamination and how these tissue levels can be related to alterations in macroinvertebrate communities in the dredged River Dommel. Metal accumulation was measured in translocated zebra mussels (Dreissena polymorpha) and resident Chironomidae. Furthermore, macroinvertebrate community composition was assessed. Our results indicated that trends of total metal concentrations in surface water of the Dommel in time are reflected well by metal levels in tissue of D. polymorpha. In contrast, sediment-bound metals were the most dominant exposure route for Chironomidae. Alterations in macroinvertebrate community composition were observed during dredging and significant relations between metal levels in invertebrate tissues and ecological responses were found. Our results demonstrated that metal accumulation in both zebra mussels and Chironomidae can be used as an integrated measure of metal bioavailability and to predict ecological effects of metal toxicity on macroinvertebrate communities. - Highlights: ► The use of tissue concentrations to assess environmental metal pollution was studied. ► Metal accumulation was measured in caged zebra mussels and resident Chironomidae. ► Shell condition of mussels and macroinvertebrate taxa distribution was assessed. ► Different accumulation between biota and relations with community level were found. ► Bioaccumulation is an integrated measure of metal toxicity in aquatic communities. - Metal accumulation in selected aquatic invertebrates can be used as an integrated measure of metal bioavailability and to predict ecological effects of metal toxicity.

  6. Habitat shift in invading species: Zebra and quagga mussel population characteristics on shallow soft substrates

    Science.gov (United States)

    Berkman, P.A.; Garton, D.W.; Haltuch, M.A.; Kennedy, G.W.; Febo, L.R.

    2000-01-01

    Unexpected habitat innovations among invading species are illustrated by the expansion of dreissenid mussels across sedimentary environments in shallow water unlike the hard substrates where they are conventionally known. In this note, records of population characteristics of invading zebra (Dreissena polymorpha) and quagga (Dreissena bugensis) mussels from 1994 through 1998 are reported from shallow (less than 20 m) sedimentary habitats in western Lake Erie. Haphazard SCUBA collections of these invading species indicated that combined densities of zebra and quagga mussels ranged from 0 to 32,500 individuals per square meter between 1994 and 1998, with D. polymorpha comprising 75-100% of the assemblages. These mixed mussel populations, which were attached by byssal threads to each other and underlying sand-grain sediments, had size-frequency distributions that were typical of colonizing populations on hard substrates. Moreover, the presence of two mussel cohorts within the 1994 samples indicated that these species began expanding onto soft substrates not later than 1992, within 4 years of their initial invasion in western Lake Erie. Such historical data provide baselines for interpreting adaptive innovations, ecological interactions and habitat shifts among the two invading dreissenid mussel species in North America.

  7. Are Predators Limiting Zebra Mussel Colonization of Unionid Mussels in Great Lake Coastal Wetlands?

    Science.gov (United States)

    de Szalay, F. A.; Bowers, R.

    2005-05-01

    Although many native mollusc populations have been eliminated in the Laurentian Great Lakes by the exotic zebra mussel, recent surveys have found abundant unionid (Bivalvia: Unionidae) populations in some coastal wetlands. Unionid burrowing in soft sediments and predation by fish have been shown to reduce numbers of attached zebra mussels, and we tested these factors in a Lake Erie coastal wetland. In 2002, we held live unionids (Leptodea fragilis, Quadrula quadrula) and Pyganodon grandis shells in exclosures with wire mesh bottoms that were buried to sediment depths of either 5, 10, or 20 cm. After 2 months, numbers of attached dreissenids on unionids were significantly higher inside all exclosure treatments than outside exclosures. This indicated that either unionid burrowing was prevented in all sediment depth treatments or molluscivores were excluded by exclosures. In 2004, we measured dreissenid colonization on Q. quadrula and PVC plates in bottomless exclosures with different mesh sizes. After 6 months, dreissenid numbers on PVC plates and on Q. quadrula in 2.5 cm X 2.5 cm and 5 cm X 10 cm mesh exclosures were significantly higher than in open exclosures. These data suggest that molluscivores are important in limiting dreissenids in Great Lake coastal wetlands.

  8. Skin-deep diagnosis: affective bias and zebra retreat complicating the diagnosis of systemic sclerosis.

    Science.gov (United States)

    Miller, Chad S

    2013-01-01

    Nearly half of medical errors can be attributed to an error of clinical reasoning or decision making. It is estimated that the correct diagnosis is missed or delayed in between 5% and 14% of acute hospital admissions. Through understanding why and how physicians make these errors, it is hoped that strategies can be developed to decrease the number of these errors. In the present case, a patient presented with dyspnea, gastrointestinal symptoms and weight loss; the diagnosis was initially missed when the treating physicians took mental short cuts and used heuristics as in this case. Heuristics have an inherent bias that can lead to faulty reasoning or conclusions, especially in complex or difficult cases. Affective bias, which is the overinvolvement of emotion in clinical decision making, limited the available information for diagnosis because of the hesitancy to acquire a full history and perform a complete physical examination in this patient. Zebra retreat, another type of bias, is when a rare diagnosis figures prominently on the differential diagnosis but the physician retreats for various reasons. Zebra retreat also factored in the delayed diagnosis. Through the description of these clinical reasoning errors in an actual case, it is hoped that future errors can be prevented or inspiration for additional research in this area will develop.

  9. pocketZebra: a web-server for automated selection and classification of subfamily-specific binding sites by bioinformatic analysis of diverse protein families.

    Science.gov (United States)

    Suplatov, Dmitry; Kirilin, Eugeny; Arbatsky, Mikhail; Takhaveev, Vakil; Svedas, Vytas

    2014-07-01

    The new web-server pocketZebra implements the power of bioinformatics and geometry-based structural approaches to identify and rank subfamily-specific binding sites in proteins by functional significance, and select particular positions in the structure that determine selective accommodation of ligands. A new scoring function has been developed to annotate binding sites by the presence of the subfamily-specific positions in diverse protein families. pocketZebra web-server has multiple input modes to meet the needs of users with different experience in bioinformatics. The server provides on-site visualization of the results as well as off-line version of the output in annotated text format and as PyMol sessions ready for structural analysis. pocketZebra can be used to study structure-function relationship and regulation in large protein superfamilies, classify functionally important binding sites and annotate proteins with unknown function. The server can be used to engineer ligand-binding sites and allosteric regulation of enzymes, or implemented in a drug discovery process to search for potential molecular targets and novel selective inhibitors/effectors. The server, documentation and examples are freely available at http://biokinet.belozersky.msu.ru/pocketzebra and there are no login requirements. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

  10. Similar but Different: Dynamic Social Network Analysis Highlights Fundamental Differences between the Fission-Fusion Societies of Two Equid Species, the Onager and Grevy's Zebra.

    Directory of Open Access Journals (Sweden)

    Daniel I Rubenstein

    Full Text Available Understanding why animal societies take on the form that they do has benefited from insights gained by applying social network analysis to patterns of individual associations. Such analyses typically aggregate data over long time periods even though most selective forces that shape sociality have strong temporal elements. By explicitly incorporating the temporal signal in social interaction data we re-examine the network dynamics of the social systems of the evolutionarily closely-related Grevy's zebras and wild asses that show broadly similar social organizations. By identifying dynamic communities, previously hidden differences emerge: Grevy's zebras show more modularity than wild asses and in wild asses most communities consist of solitary individuals; and in Grevy's zebras, lactating females show a greater propensity to switch communities than non-lactating females and males. Both patterns were missed by static network analyses and in general, adding a temporal dimension provides insights into differences associated with the size and persistence of communities as well as the frequency and synchrony of their formation. Dynamic network analysis provides insights into the functional significance of these social differences and highlights the way dynamic community analysis can be applied to other species.

  11. Extracellular acidification activates ovarian cancer G-protein-coupled receptor 1 and GPR4 homologs of zebra fish

    Energy Technology Data Exchange (ETDEWEB)

    Mochimaru, Yuta [Laboratory of Cell Signaling Regulation, Department of Life Sciences, School of Agriculture, Meiji University, Kawasaki 214-8571 (Japan); Azuma, Morio [Laboratory of Regulatory Biology, Graduate School of Science and Engineering, University of Toyama, 3190 Gofuku, Toyama 930-8555 (Japan); Oshima, Natsuki; Ichijo, Yuta; Satou, Kazuhiro [Laboratory of Cell Signaling Regulation, Department of Life Sciences, School of Agriculture, Meiji University, Kawasaki 214-8571 (Japan); Matsuda, Kouhei [Laboratory of Regulatory Biology, Graduate School of Science and Engineering, University of Toyama, 3190 Gofuku, Toyama 930-8555 (Japan); Asaoka, Yoichi; Nishina, Hiroshi [Department of Developmental and Regenerative Biology, Medical Research Institute, Tokyo Medical and Dental University, Tokyo 113-8510 (Japan); Nakakura, Takashi [Department of Anatomy, Graduate School of Medicine, Teikyo University, 2-11-1 Kaga Itabashi-Ku, Tokyo 173-8605 (Japan); Mogi, Chihiro; Sato, Koichi; Okajima, Fumikazu [Laboratory of Signal Transduction, Institute for Molecular and Cellular Regulation, Gunma University, Maebashi 371-8512 (Japan); Tomura, Hideaki, E-mail: tomurah@meiji.ac.jp [Laboratory of Cell Signaling Regulation, Department of Life Sciences, School of Agriculture, Meiji University, Kawasaki 214-8571 (Japan)

    2015-02-20

    Mammalian ovarian G-protein-coupled receptor 1 (OGR1) and GPR4 are identified as a proton-sensing G-protein-coupled receptor coupling to multiple intracellular signaling pathways. In the present study, we examined whether zebra fish OGR1 and GPR4 homologs (zOGR1 and zGPR4) could sense protons and activate the multiple intracellular signaling pathways and, if so, whether the similar positions of histidine residue, which is critical for sensing protons in mammalian OGR and GPR4, also play a role to sense protons and activate the multiple signaling pathways in the zebra fish receptors. We found that extracellular acidic pH stimulated CRE-, SRE-, and NFAT-promoter activities in zOGR1 overexpressed cells and stimulated CRE- and SRE- but not NFAT-promoter activities in zGPR4 overexpressed cells. The substitution of histidine residues at the 12th, 15th, 162th, and 264th positions from the N-terminal of zOGR1 with phenylalanine attenuated the proton-induced SRE-promoter activities. The mutation of the histidine residue at the 78th but not the 84th position from the N-terminal of zGPR4 to phenylalanine attenuated the proton-induced SRE-promoter activities. These results suggest that zOGR1 and zGPR4 are also proton-sensing G-protein-coupled receptors, and the receptor activation mechanisms may be similar to those of the mammalian receptors. - Highlights: • Zebra fish OGR1 and GPR4 homologs (zOGR1, zGPR4) are proton-sensing receptors. • The signaling pathways activated by zOGR1 and zGPR4 are different. • Histidine residues critical for sensing protons are conserved.

  12. Comparative genomic data of the Avian Phylogenomics Project.

    Science.gov (United States)

    Zhang, Guojie; Li, Bo; Li, Cai; Gilbert, M Thomas P; Jarvis, Erich D; Wang, Jun

    2014-01-01

    The evolutionary relationships of modern birds are among the most challenging to understand in systematic biology and have been debated for centuries. To address this challenge, we assembled or collected the genomes of 48 avian species spanning most orders of birds, including all Neognathae and two of the five Palaeognathae orders, and used the genomes to construct a genome-scale avian phylogenetic tree and perform comparative genomics analyses (Jarvis et al. in press; Zhang et al. in press). Here we release assemblies and datasets associated with the comparative genome analyses, which include 38 newly sequenced avian genomes plus previously released or simultaneously released genomes of Chicken, Zebra finch, Turkey, Pigeon, Peregrine falcon, Duck, Budgerigar, Adelie penguin, Emperor penguin and the Medium Ground Finch. We hope that this resource will serve future efforts in phylogenomics and comparative genomics. The 38 bird genomes were sequenced using the Illumina HiSeq 2000 platform and assembled using a whole genome shotgun strategy. The 48 genomes were categorized into two groups according to the N50 scaffold size of the assemblies: a high depth group comprising 23 species sequenced at high coverage (>50X) with multiple insert size libraries resulting in N50 scaffold sizes greater than 1 Mb (except the White-throated Tinamou and Bald Eagle); and a low depth group comprising 25 species sequenced at a low coverage (~30X) with two insert size libraries resulting in an average N50 scaffold size of about 50 kb. Repetitive elements comprised 4%-22% of the bird genomes. The assembled scaffolds allowed the homology-based annotation of 13,000 ~ 17000 protein coding genes in each avian genome relative to chicken, zebra finch and human, as well as comparative and sequence conservation analyses. Here we release full genome assemblies of 38 newly sequenced avian species, link genome assembly downloads for the 7 of the remaining 10 species, and provide a guideline of

  13. IMPACT OF THE DURATION OF BACTERIAL EXPOSURE ON ZEBRA MUSSEL MORTALITY

    International Nuclear Information System (INIS)

    Molloy, Daniel P.

    2002-01-01

    These tests indicated that: (1) duration of exposure to bacterial strain CL0145A of Pseudomonas fluorescens is a key variable in obtaining zebra mussel mortality; (2) that given a choice of exposure periods up to 96 hr, the longer the exposure period, the higher the mean mortality that will be achieved; (3) that the first few hours that the mussels are exposed to the bacteria are the most important in achieving kill; (4) that the mortality achieved by exposure periods ≥72 hr may be somewhat amplified by the degraded water quality conditions which can develop in recirculating water systems over such extended time periods

  14. IMPACT OF THE DURATION OF BACTERIAL EXPOSURE ON ZEBRA MUSSEL MORTALITY

    Energy Technology Data Exchange (ETDEWEB)

    Daniel P. Molloy

    2002-01-21

    These tests indicated that: (1) duration of exposure to bacterial strain CL0145A of Pseudomonas fluorescens is a key variable in obtaining zebra mussel mortality; (2) that given a choice of exposure periods up to 96 hr, the longer the exposure period, the higher the mean mortality that will be achieved; (3) that the first few hours that the mussels are exposed to the bacteria are the most important in achieving kill; (4) that the mortality achieved by exposure periods {>=}72 hr may be somewhat amplified by the degraded water quality conditions which can develop in recirculating water systems over such extended time periods.

  15. The Effects of Zebra Mussels (Dreissena polymorpha) on the Foraging Success of Eurasian Perch (Perca fluviatilis) and Ruffe (Gymnocephalus cernuus)

    Science.gov (United States)

    Dieterich, Axel; Mörtl, Martin; Eckmann, Reiner

    2004-07-01

    Complex habitat structures can influence the foraging success of fish. Competition for food between fish species can therefore depend on the competitors' abilities to cope with structural complexity. In laboratory experiments, we comparatively assessed effects of zebra mussels (Dreissena polymorpha Pall.) on the foraging success of Eurasian perch (Perca fluviatilis L.) and ruffe (Gymnocephalus cernuus (L.)). In single-species and mixed-species experiments, the fish were fed caddisfly larvae (Tinodes waeneri (L.)) over complex (mussel-covered stones) and less-complex (bare stones) substrates. With intraspecific competition, food consumption by perch and ruffe decreased significantly when the complex substrate was used. With interspecific competition, food consumption by perch and ruffe did not change with substrate complexity, but perch clearly out-competed ruffe on both substrates. Zebra mussel beds provide a refuge for macrozoobenthos against predation by ruffe and probably also by perch. (

  16. Expression, purification, crystallization and preliminary X-ray analysis of a C-terminal fragment of the Epstein–Barr virus ZEBRA protein

    Energy Technology Data Exchange (ETDEWEB)

    Morand, Patrice [European Molecular Biology Laboratory, Grenoble Outstation, BP 181, 38042 Grenoble CEDEX 9 (France); Laboratoire de Virologie Moléculaire et Structurale, EA 2939, Université Joseph Fourier, Grenoble (France); Budayova-Spano, Monika [European Molecular Biology Laboratory, Grenoble Outstation, BP 181, 38042 Grenoble CEDEX 9 (France); Perrissin, Monique [Laboratoire de Virologie Moléculaire et Structurale, EA 2939, Université Joseph Fourier, Grenoble (France); Müller, Christoph W., E-mail: mueller@embl-grenoble.fr; Petosa, Carlo [European Molecular Biology Laboratory, Grenoble Outstation, BP 181, 38042 Grenoble CEDEX 9 (France)

    2006-03-01

    A C-terminal fragment of the Epstein–Barr virus lytic switch protein ZEBRA has been crystallized in complex with DNA. A C-terminal fragment of the Epstein–Barr virus immediate-early transcription factor ZEBRA has been expressed as a recombinant protein in Escherichia coli and purified to homogeneity. The fragment behaves as a dimer in solution, consistent with the presence of a basic region leucine-zipper (bZIP) domain. Crystals of the fragment in complex with a DNA duplex were grown by the hanging-drop vapour-diffusion technique using polyethylene glycol 4000 and magnesium acetate as crystallization agents. Crystals diffract to better than 2.5 Å resolution using synchrotron radiation (λ = 0.976 Å). Crystals belong to space group C2, with unit-cell parameters a = 94.2, b = 26.5, c = 98.1 Å, β = 103.9°.

  17. Patent urachus with subsequent joint infection in a free-living Grevy's zebra foal.

    Science.gov (United States)

    Ndung'u, Francis K; Ndegwa, Margaret W; deMaar, Thomas W J

    2003-01-01

    A free-living, female Grevy's zebra (Equus grevyi) foal was found lethargic, lame, with swollen joints, pyrexia, and urine dripping from the umbilicus. It died 2 days later despite intensive care. Gross examination revealed patent urachus and suppurative arthritis. Swabs were taken from the joints, the patent urachus, and urine for bacteriology. The dominant isolate was Escherichia coli. The joint infection was probably secondary to septicemia, resulting from the patent urachus. To our knowledge, this is the first report of neonatal patent urachus in a wild equid.

  18. Biologia reprodutiva e dinâmica populacional de Hypancistrus zebra Isbrücker & Nijssen, 1991 (Siluriformes, Loricariidae), no rio Xingu, Amazônia brasileira

    OpenAIRE

    ROMAN, Ana Paula Oliveira

    2011-01-01

    Hypancistrus zebra é uma espécie ornamental, endêmica e rara da região do Médio – Baixo Rio Xingu, a qual apresenta forte demanda do mercado de peixes ornamentais internacional, que criou uma forte pressão de exploração associada a esta espécie. Atualmente, H.zebra encontra-se na lista brasileira de fauna ameaçada de extinção e sua captura está proibida. Sabe-se que mesmo proibida, a mesma continua sendo capturada e exportada ilegalmente, aliada a isso a construção da Hidrelétrica de Belo Mon...

  19. Zebra Chip disease and potato biochemistry: Tuber physiological changes in response to ‘Candidatus Liberibacter solanacearum’ infection over time

    Science.gov (United States)

    Zebra chip disease (ZC), putatively caused by ‘Candidatus Liberibacter solanacearum’ (Lso), is of increasing concern to potato production in Mexico, the United States, and New Zealand. However, little is known about host tuber physiological changes that result in ZC symptom formation. This study exp...

  20. Food intake rates and habitat segregation of tufted duck Aythya fuligula scaup Aythya marila exploiting zebra mussels Dreissena Polymorpha

    NARCIS (Netherlands)

    Leeuw, de J.J.

    1999-01-01

    The foraging skills of Tufted Duck Aythya fuligula and Scaup Aythya marila feeding on Zebra Mussels Dreissena polymorpha were studied in experiments under semi-natural diving conditions with relevance to the IJsselmeer/Markermeer area (large lakes in the centre of The Netherlands, former Zuiderzee