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Sample records for zebra equus zebra

  1. 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. PMID:20833476

  2. The reaction of the Cape Mountain Zebra (Equus Zebra Zebra to certain chemical immobilisation drugs

    Directory of Open Access Journals (Sweden)

    E Young

    1972-01-01

    Full Text Available he physiological reactions evoked by M@99 and Aza- perone in the Cape Mountain Zebra (Equus zebra Zebra are discussed. Notes on clinical as well as physiological parameters are presented and it is concluded that these drugs can be used effectively in the capture of individuals of this rare mammal.

  3. In vitro isolation of equine piroplasms derived from Cape Mountain zebra ( Equus zebra zebra) in South Africa

    OpenAIRE

    Zweygarth, Erich; Meyer, P.; Lopez-rebollar, Laura M.

    2002-01-01

    Twenty blood samples of zebras ( Equus zebra zebra) from the Karoo National Park and the Bontebok National Park in South Africa, all seropositive for Theileria equi, were subjected to in vitro culture to identify carrier animals and to isolate the parasites. Sixteen animals had a detectable parasitaemia in Giemsa-stained blood smears examined before culture initiation, the remaining four animals were identified as T. equi carriers by in vitro culture. Cultures were initiated either in an oxyg...

  4. Prevalence and body distribution of sarcoids in South African Cape mountain zebra (Equus zebra zebra

    Directory of Open Access Journals (Sweden)

    D. Zimmerman

    2012-06-01

    Full Text Available There are no reports in the literature describing any tumours, and specifically sarcoids, in zebras. The equine sarcoid, a locally aggressive, fibroblastic skin tumour, is the most common dermatological neoplasm reported in horses. The Cape mountain zebra (CMZ has been described as one of the most vulnerable mammals in South Africa with current populations existing in isolated units. All South African CMZ are descendants from no more than 30 individual animals originating from 3 populations, namely the Mountain Zebra National Park, and Kammanassie and Gamka Mountain Nature Reserves near Cradock. The possibility therefore exists that the existing populations arose from a very small gene pool and that they are considerably inbred. A reduction in major histocompatibility complex diversity due to genetic bottlenecks and subsequent inbreeding probably contributed to uniform population sensitivity and the subsequent development of sarcoid in two CMZ populations, namely in the Bontebok National Park and Gariep Nature Reserve. The entire population of CMZ in the Bontebok National Park was observed and sampled during 2002 to document the prevalence and body distribution of sarcoids. During the same year, a comparative study was carried out on an outbred population of Burchell's zebra in the Kruger National Park. The prevalence in CMZ in the Bontebok National Park was 53 %, while the Burchell's zebra in Kruger National Park had a prevalence of 1.9 %. The most common sites for sarcoid in CMZ were the ventral abdomen and limbs. Prevalence of sarcoids in horses recorded in the literature varies between 0.5%and 2%. The Gariep Nature Reserve recently reported a prevalence of almost 25 % in CMZ in the reserve.

  5. Descriptive study of an outbreak of equine sarcoid in a population of Cape mountain zebra (Equus zebra zebra in the Gariep Nature Reserve

    Directory of Open Access Journals (Sweden)

    P.N. Thompson

    2012-06-01

    Full Text Available An outbreak of equine sarcoid occurred in a population of Cape mountain zebra (Equus zebra zebra at the Gariep Nature Reserve located in the southern Free State Province of South Africa in 1996. The course of the outbreak during 1996 to 2003 is described. During this period the average population size was 69 animals. Initially (1996 all affected animals were removed from the population. New cases continued to manifest and the incidence varied between 4.6% and 17.6 %. Prevalence reached 24.7% in 2002. No sexual predilection was noticed in the 39 recorded cases. Of the affected individuals, 64 % had a single lesion and no animal had more than 4 lesions. In males, the majority of lesions occurred in the inguinal area (55.17 %, whereas in females they mostly occurred on the head and neck (41.38 %. Lesions can increase 260 % in size annually and may impede movement.

  6. 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. PMID:20458869

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

    OpenAIRE

    Lampen, F.; Bhoora, Raksha; Collins, Nicola E.; Penzhorn, Barend Louis

    2009-01-01

    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 piro...

  8. Epidemiology of African horsesickness : duration of viraemia in zebra (Equus burchelli)

    OpenAIRE

    Barnard, B.J.H.; Bengis, Roy G.; Keet, D.F.; Dekker, E.H.

    1994-01-01

    The viraemic period of African horsesickness is significantly longer in experimentally infected zebra than in horses. The virus could be isolated 40 d post-infection from blood and 48 d post-infection from spleen. The introduction of zebra into African horsesickness-free countries should therefore be considered carefully, and preferably be restricted to serologically negative zebra.

  9. Uneven distribution of enamel in the tooth crown of a Plains Zebra (Equus quagga)

    Science.gov (United States)

    Kaiser, Thomas M.

    2015-01-01

    Unworn teeth of herbivorous mammals are not immediately functional. They have to be partially worn to expose enamel ridges which can then act as shear-cutting blades to break the food down. We use the Plains Zebra (Equus quagga) as a hypsodont, herbivorous model organism to investigate how initial wear of the tooth crown is controlled by underlying structures. We find that the enamel proportion is smaller at the apical half of the tooth crown in all upper tooth positions and suggest that lower enamel content here could promote early wear. Besides this uneven enamel distribution, we note that the third molar has a higher overall enamel content than any other tooth position. The M3 is thus likely to have a slightly different functional trait in mastication, resisting highest bite forces along the tooth row and maintaining functionality when anterior teeth are already worn down. PMID:26082860

  10. Basis for the photoidentification of zebras (Equus burchellii in the National Zoological Garden of Cuba

    Directory of Open Access Journals (Sweden)

    Ernesto Testé Lozano

    2013-09-01

    Full Text Available Variability in facial strip patterns in zebras aloud its individualization. This is the basis for photo identification techniques that substitute traditional marking methods that can be expensive and traumatic. Current paper present an identification key of Equus burchelli captive in the National Zoological Garden of Cuba using left side pictures of their faces. Region of interest was limited by axes traced from posterior mouth edge, the eye and the lower base of neck. Strips crossing each ax were counted building a numerical code for each individual. The 68 % of captive zebras (54 individuals were photo identified. A group of 12 individuals had a code completely different from others, identifying each one. Remaining individuals could be grouped by similar codes, resulting in 11 pairs, and four groups of three, four, five and six individuals each. Every individual was characterized by the occurrence of spots, truncated strips, bridges between vertical stripes, periorbital bands, and bifurcated stripes. With all this characters a visual identification key was developed.

  11. Putative clinical piroplasmosis in a Burchell’s zebra (Equus quagga burchelli)

    Scientific Electronic Library Online (English)

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

    Full Text Available A 10-year-old tame zebra gelding was presented after sufferingfrom 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 haema [...] tology 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. Putative clinical piroplasmosis in a Burchell's zebra (Equus quagga burchelli : clinical communication

    Directory of Open Access Journals (Sweden)

    N.E. Collins

    2012-05-01

    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.

  13. Characterization of Streptococcus equi subsp. ruminatorum isolated from spotted hyenas (Crocuta crocuta) and plains zebras (Equus burchelli), and identification of a M-like protein (SrM) encoding gene

    OpenAIRE

    2008-01-01

    Characterization of Streptococcus equi subsp. ruminatorum isolated from spotted hyenas (Crocuta crocuta) and plains zebras (Equus burchelli), and identification of a M-like protein (SrM) encoding gene

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

    OpenAIRE

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

    2012-01-01

    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 piro...

  15. 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. PMID:25380362

  16. 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 differ by an average of 70 kg and 102 kg for stallions and mares respectively. Average birth mass for zebra was 33,7 kg. The largest foetus had a body mass of 39,0 kilogram. Foetal growth curves are provided. The first signs of body stripes occur at between 250 and 270 days of pregnancy (gestation period = 375 days.

  17. Zebra Finch Song Archive

    Science.gov (United States)

    The Zebra Finch Song Archive was developed by Biology Professor Heather Williams of Williams College as an informational web resource. The archive currently contains songs and sonograms for 83 male zebra finches that are all descendants from a single pair. Songs can be accessed through a tabular form titled Birds and Clutches or through a well-designed Family Tree. For site visitors that would like more background about the zebra finch (including its song and brain), see the Bird Songs and Bird Brains section.

  18. 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.

  19. Shedding of Clostridium difficile PCR ribotype 078 by zoo animals, and report of an unstable metronidazole-resistant isolate from a zebra foal (Equus quagga burchellii).

    Science.gov (United States)

    Álvarez-Pérez, Sergio; Blanco, José L; Martínez-Nevado, Eva; Peláez, Teresa; Harmanus, Celine; Kuijper, Ed; García, Marta E

    2014-03-14

    Clostridium difficile is an emerging and potentially zoonotic pathogen, but its prevalence in most animal species, including exhibition animals, is currently unknown. In this study we assessed the prevalence of faecal shedding of C. difficile by zoo animals, and determined the ribotype, toxin profile and antimicrobial susceptibility of recovered isolates. A total of 200 samples from 40 animal species (36.5% of which came from plains zebra, Equus quagga burchellii) were analysed. C. difficile was isolated from 7 samples (3.5% of total), which came from the following animal species: chimpanzee (Pan troglodytes troglodytes), dwarf goat (Capra hircus), and Iberian ibex (Capra pyrenaica hispanica), with one positive sample each; and plains zebra, with 4 positive samples from 3 different individuals. Most recovered isolates (4/7, 57.1%) belonged to the epidemic PCR ribotype 078, produced toxins A and B, and had the genes encoding binary toxin (i.e. A(+)B(+)CDT(+) isolates). The remaining three isolates belonged to PCR ribotypes 039 (A(-)B(-)CDT(-)), 042 (A(+)B(+)CDT(-)) and 110 (A(-)B(+)CDT(-)). Regardless of their ribotype, all isolates displayed high-level resistance to the fluoroquinolones ciprofloxacin, enrofloxacin and levofloxacin. Some isolates were also resistant to meropenem and/or ertapenem. A ribotype 078 isolate recovered from a male zebra foal initially showed in vitro resistance to metronidazole (MIC ? 256 ?g/ml), but lost that trait after subculturing on non-selective media. We conclude that zoo animals belonging to different species can carry ribotype 078 and other toxigenic strains of C. difficile showing resistance to antimicrobial compounds commonly used in veterinary and/or human medicine. PMID:24467928

  20. Observing the Zebra Finch.

    Science.gov (United States)

    Waters, Charles

    1979-01-01

    Presents natural history information on the zebra finch (Taeniopygia castanotis) for the biology teacher. Includes a section on care of the birds in the classroom and a method for constructing an inexpensive cage. (SA)

  1. Advances in ZEBRA batteries

    Science.gov (United States)

    Dustmann, Cord-H.

    ZEBRA batteries use plain salt and nickel as the raw material for their electrodes in combination with a ceramic electrolyte and a molten salt. This combination provides a battery system related specific energy of 120 Wh/kg and a specific power of 180 W/kg. With these data the battery is well designed for all types of electric vehicles and hybrid electric buses. The ZEBRA battery technology is industrialised in Switzerland where a new plant has a capacity of 2000 packs a year with expansion prepared for 30,000 packs a year.

  2. The zebra mussel

    International Nuclear Information System (INIS)

    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).

  3. Circulation of African horsesickness virus in zebra (Equus burchelli) in the Kruger National Park, South Africa, as measured by the prevalence of type specific antibodies

    OpenAIRE

    Barnard, B.J.H.

    1993-01-01

    In the Kruger National Park 75% of zebra foals are born in October-March and they lose their passive immunity against African horsesickness virus (AHSV) when they are 5-6 months old. One month later infection with different serotypes of AHSV amounts to 31% and thereafter infections increase rapidly to almost 100% before the foals are 12 months old. The capability of zebra to maintain AHSV is clearly illustrated by the continuing infections during every month of the year with a peak p...

  4. How landscape scale changes affect ecological processes in conservation areas: external factors influence land use by zebra (Equus burchelli) in the Okavango Delta

    OpenAIRE

    Bartlam-brooks, Hattie L. A.; Bonyongo, Mpaphi C.; Harris, Stephen

    2013-01-01

    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 e...

  5. ZEBRA battery meets USABC goals

    Science.gov (United States)

    Dustmann, Cord-H.

    In 1990, the California Air Resources Board has established a mandate to introduce electric vehicles in order to improve air quality in Los Angeles and other capitals. The United States Advanced Battery Consortium has been formed by the big car companies, Electric Power Research Institute (EPRI) and the Department of Energy in order to establish the requirements on EV-batteries and to support battery development. The ZEBRA battery system is a candidate to power future electric vehicles. Not only because its energy density is three-fold that of lead acid batteries (50% more than NiMH) but also because of all the other EV requirements such as power density, no maintenance, summer and winter operation, safety, failure tolerance and low cost potential are fulfilled. The electrode material is plain salt and nickel in combination with a ceramic electrolyte. The cell voltage is 2.58 V and the capacity of a standard cell is 32 Ah. Some hundred cells are connected in series and parallel to form a battery with about 300 V OCV. The battery system including battery controller, main circuit-breaker and cooling system is engineered for vehicle integration and ready to be mounted in a vehicle [J. Gaub, A. van Zyl, Mercedes-Benz Electric Vehicles with ZEBRA Batteries, EVS-14, Orlando, FL, Dec. 1997]. The background of these features are described.

  6. Dynamics of zebra finch and mockingbird vocalizations

    Science.gov (United States)

    Cimenser, Aylin

    Along with humans, whales, and bats, three groups of birds which include songbirds (oscines) such as the Zebra Finch (Taeniopygia guttata) and Mockingbird (Mimus polyglottos) are the only creatures known to learn sounds by imitation. Numerous similarities between human and songbird vocalizations exist and, recently, it has been shown that Zebra Finch in particular possesses a gene, FoxP2, known to be involved in human language. This thesis investigates song development in Zebra Finches, as well as the temporal dynamics of song in Mockingbirds. Zebra Finches have long been the system of choice for studying vocal development, ontogeny, and complexity in birdsong. Physicists find them intriguing because the spectrally complex vocalizations of the Zebra Finch can exhibit sudden transitions to chaotic dynamics, period doubling & mode-locking phenomena. Mockingbirds, by contrast, provide an ideal system to examine the richness of an avian repertoire, since these musically versatile songbirds typically know upwards of 200 songs. To analyse birdsong data, we have developed a novel clustering algorithm that can be applied to the bird's syllables, tracing their dynamics back to the earliest stages of vocal development. To characterize birdsong we have used Fourier techniques, based upon multitaper spectral analysis, to optimally work around the constraints imposed by (Heisenberg's) time-frequency uncertainty principle. Furthermore, estimates that provide optimal compromise between frequency and temporal resolution have beautiful connections with solutions to the Helmholtz wave equation in prolate spheroidal coordinates. We have used this connection to provide firm foundation for certain heuristics used in the literature to compute associated spectral derivatives and supply a pedagogical account here in this thesis. They are of interest because spectral derivatives emphasize sudden changes in the dynamics of the underlying phenomenon, and often provide a nice way to visualize such dynamics. Our Zebra Finch data consist of continuous recordings of six tutored birds from the early, plastic stages of sound production to the development of fully crystallized mature song. Our analysis reveals that well before the Zebra Finch hears adult song, identifiably distinct clusters are observable for all birds in the same regions of feature space. (Abstract shortened by UMI.)

  7. 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. PMID:17531057

  8. Prevalence of antibodies against some equine viruses in zebra (Zebra burchelli) in the Kruger National Park, 1991-1992

    OpenAIRE

    Barnard, B.J.H.; Paweska, J T

    1993-01-01

    The presence of antibodies against equine encephalosis virus (EEV) and equid herpesvirus 1 and 4 in zebra in the Kruger National Park (KNP) was demonstrated. The ability of zebra to maintain immunity against EEV is illustrated by the appearance of neutralizing antibodies in most zebra foals within months of losing their maternal immunity. This occurs in every month of the year, even in winter. The high proportion of serologically positive foals in winter is ascribed to the presenc...

  9. Physico-chemical, microbiological, textural and sensory attributes of matured game salami produced from springbok (Antidorcas marsupialis), gemsbok (Oryx gazella), kudu (Tragelaphus strepsiceros) and zebra (Equus burchelli) harvested in Namibia.

    Science.gov (United States)

    van Schalkwyk, D L; McMillin, K W; Booyse, Mardé; Witthuhn, R C; Hoffman, L C

    2011-05-01

    Differences and consumer acceptability of matured salami produced from game species were evaluated. The pH of the salami differed (p 0.05) were observed among the species for a(w), shear force, gumminess or cohesiveness. Microbiological counts of the game salami differed for coliform (p 0.05) counts. The most distinctive characteristics observed by the quantitative descriptive analyses were smoky, salty, pepper and salami flavour, combined with a smoky, salami aroma. Game flavour was not perceived as a strong attribute during the sensory analyses. Gemsbok salami was strongly associated with the attribute colour as described by the male and female consumer panels. The springbok salami scored the lowest for both colour and taste. Salami produced from gemsbok, kudu and zebra were superior to springbok salami. PMID:21185658

  10. The Zebra Multi-Chamber Scanning System

    International Nuclear Information System (INIS)

    The Multi-Chamber Scanning System developed for the zero-power fast reactor Zebra comprises an integral array of 150 parallel-plate fission chambers loaded into fuel elements in a similar manner to standard core components. The chamber outputs are counted sequentially under computer control to provide a rapid three-dimensional power mapping facility. The report describes the basic concept, design and calibration of the fission chambers, design of the electronics and computer interface, and overall system performance as exemplified by measurements on a mock-up of the core of the Prototype Past Reactor. (author)

  11. 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.

  12. 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. PMID:12685093

  13. Zebra and Quagga Mussel Distribution in North America - Direct Download

    U.S. Geological Survey, Department of the Interior — The concern caused by the explosive spread of the zebra mussel, (Dreissena polymorpha), within the United States resulted in passage of the Nonindigenous Aquatic...

  14. Zebra: An advanced PWR lattice code

    International Nuclear Information System (INIS)

    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)

  15. 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)

  16. The zebra finch neuropeptidome: prediction, detection and expression

    Directory of Open Access Journals (Sweden)

    Annangudi Suresh P

    2010-04-01

    Full Text Available Abstract Background Among songbirds, the zebra finch (Taeniopygia guttata is an excellent model system for investigating the neural mechanisms underlying complex behaviours such as vocal communication, learning and social interactions. Neuropeptides and peptide hormones are cell-to-cell signalling molecules known to mediate similar behaviours in other animals. However, in the zebra finch, this information is limited. With the newly-released zebra finch genome as a foundation, we combined bioinformatics, mass-spectrometry (MS-enabled peptidomics and molecular techniques to identify the complete suite of neuropeptide prohormones and final peptide products and their distributions. Results Complementary bioinformatic resources were integrated to survey the zebra finch genome, identifying 70 putative prohormones. Ninety peptides derived from 24 predicted prohormones were characterized using several MS platforms; tandem MS confirmed a majority of the sequences. Most of the peptides described here were not known in the zebra finch or other avian species, although homologous prohormones exist in the chicken genome. Among the zebra finch peptides discovered were several unique vasoactive intestinal and adenylate cyclase activating polypeptide 1 peptides created by cleavage at sites previously unreported in mammalian prohormones. MS-based profiling of brain areas required for singing detected 13 peptides within one brain nucleus, HVC; in situ hybridization detected 13 of the 15 prohormone genes examined within at least one major song control nucleus. Expression mapping also identified prohormone messenger RNAs in areas associated with spatial learning and social behaviours. Based on the whole-genome analysis, 40 prohormone probes were found on a commonly used zebra finch brain microarray. Analysis of these newly annotated transcripts revealed that six prohormone probes showed altered expression after birds heard song playbacks in a paradigm of song recognition learning; we partially verify this result experimentally. Conclusions The zebra finch peptidome and prohormone complement is now characterized. Based on previous microarray results on zebra finch vocal learning and synaptic plasticity, a number of these prohormones show significant changes during learning. Interestingly, most mammalian prohormones have counterparts in the zebra finch, demonstrating that this songbird uses similar biochemical pathways for neurotransmission and hormonal regulation. These findings enhance investigation into neuropeptide-mediated mechanisms of brain function, learning and behaviour in this model.

  17. Viral proteins associated with the Epstein-Barr virus transactivator, ZEBRA.

    OpenAIRE

    Katz, D A; Baumann, R P; Sun, R.; Kolman, J L; N Taylor; MILLER, G.

    1992-01-01

    The BamHI Z Epstein-Barr replication activator (ZEBRA) mediates disruption of latency and induction of Epstein-Barr virus (EBV) early gene expression in latently infected lymphocytes. Polyclonal rabbit sera raised against ZEBRA were used to immunoprecipitate ZEBRA-associated proteins (ZAPs). ZAPs of 19, 21, 23, and 42 kDa were coimmunoprecipitated with ZEBRA from extracts of EBV-producing lymphoid cell lines. ZAPs were not recognized directly by the rabbit sera, but they were antigenic for EB...

  18. Song Recognition in Zebra Finches: Are There Sensitive Periods for Song Memorization?

    Science.gov (United States)

    Braaten, Richard F.

    2010-01-01

    Male zebra finches learn to sing songs that they hear between 25 and 65 days of age, the sensitive period for song learning. In this experiment, male and female zebra finches were exposed to zebra finch songs either before (n = 9) or during (n = 4) the sensitive period. Following song exposure, recognition memory for the songs was assessed with an…

  19. Generation of transgenic zebra finches with replication-deficient lentiviruses.

    Science.gov (United States)

    Velho, Tarciso A F; Lois, Carlos

    2014-12-01

    Zebra finches have been a rich experimental system for studying neurobiological questions of relevance to human health for decades. In particular, finches are the leading nonhuman model organisms for investigating the biological basis of vocal learning, a critical behavioral substrate for speech acquisition. In addition, zebra finches are an ideal system for the study of brain asymmetry, hormonal control of brain development, physiological function of sleep, sex differences in the brain, behavioral-induced gene expression, and adult neurogenesis, among other questions. Despite their importance for neurobiology, the usefulness of finches as an experimental system has been restricted by a lack of genetic manipulation methods. To overcome this barrier, our laboratory has developed methods for generating transgenic birds, including zebra finches. The successful implementation of this transgenic technology by multiple research laboratories has the potential to dramatically accelerate the progress of our understanding of the genetic basis of complex biological processes such as vocal learning. Moreover, the ability to genetically manipulate zebra finches could also be used to generate novel genetic models for human disorders that cannot be studied elsewhere or that can be more easily studied in this small bird. Here, we describe a protocol to generate transgenic zebra finches using recombinant lentiviruses. PMID:25342068

  20. Mechanisms of copying behaviour in zebra finches.

    Science.gov (United States)

    Guillette, Lauren M; Healy, Susan D

    2014-10-01

    When an individual is faced with choosing between unfamiliar food options, it may benefit initially by choosing the option chosen by other animals so avoiding potentially poisonous food. It is not clear which cues the naïve forager learns from the demonstrator for choosing between food options. To determine firstly which birds (zebra finches, Taeniopygia guttata) would copy a demonstrator's choice, in Experiment 1 we presented each observer with a demonstrator feeding from one of two differently coloured feeders and then tested the observer's feeder colour preference. Of the same-sex/mixed-sex demonstrator-observer pairs tested only females copied male demonstrators. In Experiment 2, birds did not prefer either feeder colour in the absence of demonstrators confirming the social learning effect observed in Experiment 1. In Experiment 3, copying females fed significantly more at the feeder of the demonstrated colour, rather than at the location of the demonstrated feeder. These data point not just to the identity of the individual to be copied but also to the kind of information learned. PMID:25444776

  1. FindZebra : a search engine for rare diseases

    DEFF Research Database (Denmark)

    Dragusin, Radu; Petcu, Paula

    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 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. Methods: 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. Results: 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. 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 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/. © 2013 Elsevier Ireland Ltd. All rights reserved.

  2. FindZebra: A search engine for rare diseases

    DEFF Research Database (Denmark)

    Dragusin, Radu; Petcu, Paula

    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 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. Methods: We use an evaluation 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 search technology and uses curated freely available online medical information. Results: FindZebra outperformsGoogle Search in both default setup 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. 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 evaluation approach can be valuable for future development and benchmarking. The FindZebra search engine is available at http://www.findzebra.com/.

  3. Zebra - sõbralik ja lillelõhnaline / Ell-Maaja Randküla

    Index Scriptorium Estoniae

    Randküla, Ell-Maaja

    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

  4. A simple index of habitat suitability for Cape mountain zebras

    Directory of Open Access Journals (Sweden)

    A. Winkle

    1993-09-01

    Full Text Available An index of habitat suitability for Cape mountain zebras was calculated using two parameters: acceptability indices for different grass species, and the aerial cover of the grass species in the habitat. The index was tested by calculating its value for a range of different habitat patches and comparing this with the frequency of use of the patches by zebras. The close relationship between the index and the observed frequency of use verified that the index could be used as a guide to habitat suitability. Two methods were used to determine the frequency of use of the patches: counts of faecal pellet groups and frequency of sightings. Both methods yielded similar results but the pellet group counts were less time- consuming and expensive. It is recommended that the index of habitat suitability be used (i as a parameter for monitoring of long-term changes in habitat suitability in the Mountain Zebra National Park and (ii as a guide for selecting appropriate areas to re- introduce mountain zebras.

  5. Complete Genome Sequence of a Novel Circovirus from Zebra Finch

    Science.gov (United States)

    Schmitz, Anna; Peschel, Andrea; Korbel, Rüdiger

    2015-01-01

    A novel circovirus was identified in zebra finches (Taeniopygia guttata). The genome of the circovirus strain, designated 8454V25-1, comprised 1,982 nucleotides with two major open reading frames encoding a replication-associated protein and a viral capsid protein. PMID:26021933

  6. Reg outcome in an alarm situation in zebra finches

    OpenAIRE

    A?lvarez, Fernando

    2011-01-01

    Micro-PK was explored in zebra finches (Taeniopygia guttata) to test the hypothesis of nondirectional REG randomness reduction during an alarm situation. A 15-s video clip of a crawling snake was presented to 80 participants and a REG's outcome during the presentation of the stimulus was analysed under three conditions: Bird Alone, Bird Plus Observer, and Observer Alone. One 200-bit trial was collected every quarter of a second during die presentation of the stimulus and the 5-min control per...

  7. Neural correlates of nesting behavior in zebra finches (Taeniopygia guttata)

    OpenAIRE

    Hall, Zachary J.; Bertin, Marion; Bailey, Ida E.; Meddle, Simone L.; Healy, Susan D.

    2014-01-01

    •We compare markers of neural activity to nesting behavior in zebra finches.•We visualized immediate early gene (Fos) expression in nesting and control finches.•Fos production in motor, social, and reward neural circuits correlated with nesting.•Fos production correlated with material pick-up in male nesting finches.•Fos production correlated with time spent in the nest in female nesting finches.

  8. 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.

  9. Opioid modulation of song in male zebra finches (Taenopygia guttata).

    Science.gov (United States)

    Khurshid, Nazia; Jayaprakash, Navin; Hameed, L Shahul; Mohanasundaram, Sivaraj; Iyengar, Soumya

    2010-04-01

    Endogenous opioids are known to modulate motivated behaviors. Male zebra finches produce a highly motivated behavior (directed song) to court females and also sing in isolation (undirected song). We found that adult male zebra finches sang significantly fewer directed and undirected songs after administration of low doses (2.5 mg/kg body weight) of the general opioid antagonist naloxone, even though the order of syllables in songs was not altered. Surprisingly, high doses of naloxone (10 mg/kg body weight) dramatically decreased the production of undirected songs but had no significant effects on directed songs. There were no changes in the number of calls during directed or undirected song, movement, stereotyped behaviors including pecking and preening, feeding or drinking behaviors after naloxone administration. We also found that treating zebra finches with naloxone led to a decrease in tonality (goodness of pitch), frequency and amplitude modulation and an increase in the length of intersyllable intervals. Our results suggest that the opioid system can differentially modulate directed and undirected song as well as the acoustic characteristics of birdsong, perhaps by acting on different components of the song control system. PMID:20015456

  10. Parasites and diseases of Cape Mountain zebra, black wildebeest, mountain reedbuck and blesbok in the Mountain Zebra National Park

    Directory of Open Access Journals (Sweden)

    B.L. Penzhorn

    1973-07-01

    Full Text Available

    The results of a special survey are supplemented inthis report with a review of all other applicable information onthe diseases and parasites of Cape mountain zebra, black wildebeest, mountain reedbuck and blesbok in the Mountain ZebraNational Park. The possible significance of some of these infections is discussed and various suggestions are made which aim atthe continued and successful preservation of the Cape mountainzebra and other species in this National Park.

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

    International Nuclear Information System (INIS)

    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)

  12. Insect-Phytoplasma/Bacteria Relationship: Case of Potato Purple Top and Zebra Chip Diseases

    Science.gov (United States)

    Purple top and zebra chip are two important and emerging potato diseases in North and Central America. While purple top disease is well known to be caused by phytoplasmas and transmitted by leafhoppers, the exact causal agents and insect vectors of zebra chip are still unknown. The etiology of potat...

  13. Zebra body myopathy: a second case of ultrastructurally distinct congenital myopathy.

    Science.gov (United States)

    Reyes, M G; Goldbarg, H; Fresco, K; Bouffard, A

    1987-10-01

    Biopsy of the deltoid muscle of a 4-day-old baby boy with congenital hypotonia and weakness showed zebra bodies and other myopathic changes. Our patient and an other patient reported in the literature establish zebra body myopathy as an ultrastructurally distinct benign congenital myopathy. PMID:2821096

  14. Digital gene expression analysis of the zebra finch genome

    Directory of Open Access Journals (Sweden)

    Burke Terry

    2010-04-01

    Full Text Available Abstract Background In order to understand patterns of adaptation and molecular evolution it is important to quantify both variation in gene expression and nucleotide sequence divergence. Gene expression profiling in non-model organisms has recently been facilitated by the advent of massively parallel sequencing technology. Here we investigate tissue specific gene expression patterns in the zebra finch (Taeniopygia guttata with special emphasis on the genes of the major histocompatibility complex (MHC. Results Almost 2 million 454-sequencing reads from cDNA of six different tissues were assembled and analysed. A total of 11,793 zebra finch transcripts were represented in this EST data, indicating a transcriptome coverage of about 65%. There was a positive correlation between the tissue specificity of gene expression and non-synonymous to synonymous nucleotide substitution ratio of genes, suggesting that genes with a specialised function are evolving at a higher rate (or with less constraint than genes with a more general function. In line with this, there was also a negative correlation between overall expression levels and expression specificity of contigs. We found evidence for expression of 10 different genes related to the MHC. MHC genes showed relatively tissue specific expression levels and were in general primarily expressed in spleen. Several MHC genes, including MHC class I also showed expression in brain. Furthermore, for all genes with highest levels of expression in spleen there was an overrepresentation of several gene ontology terms related to immune function. Conclusions Our study highlights the usefulness of next-generation sequence data for quantifying gene expression in the genome as a whole as well as in specific candidate genes. Overall, the data show predicted patterns of gene expression profiles and molecular evolution in the zebra finch genome. Expression of MHC genes in particular, corresponds well with expression patterns in other vertebrates.

  15. 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.

  16. IRPHE-ZEBRA, AEEW Fast Reactor Experiments, Primary Documentation

    International Nuclear Information System (INIS)

    Description of program or function: ZEBRA, the zero energy breeder reactor assembly, was used to study the neutron physics of fast reactors (R D Smith, Nuclear Engineering Vol. 7 No. 76, Sept 1962, 'ZEBRA, a Zero Power Fast Reactor'). It operated from 1962 until 1982. Mock-up type assemblies representing PFR, Monju and the proposed European Fast Reactor, EFR, were studied, as well as simple assemblies for nuclear data validation. Some experiments were designed to validate the Methods used to treat the heterogeneity of the composition and to calculate control rods. Most ZEBRA assemblies were built using 2 inch square plates (51 mm square) stacked in stainless steel tubes, with the tubes, or elements, being located in holes in the reactor base plate. Blocks of 5x5 elements are grouped inside a mild steel superlattice and so the spacing of elements is not completely uniform. This size of plates was chosen to be compatible with the components in the ZPR facilities in Argonne National Laboratory and is also compatible with the MASURCA and SNEAK components, permitting these to be combined to build large assemblies. Mini-calandria containing sodium (or voided of sodium) and with uranium oxide and mixed uranium-plutonium oxide fuel in pin form (4x4 pins per mini-calandria) are also used in the later assemblies. The ZEBRA control rods use smaller components. In addition, special assemblies simulating power reactor control rods, rod followers and other singularities have been slowers and other singularities have been studied. These replace groups of elements. The compositions of the components are detailed in PLATEDATA. The arrangement of these components to form cells and the loading of the cells in elements and special assemblies is detailed in the documents listed below, together with the arrangement of the elements in the reactor. Control rod studies and sodium voiding studies have been carried out on several assemblies. Spectral indices, small sample reactivity worths and reaction rate distributions were measured on most assemblies. Neutron spectrum measurements have also been made on some assemblies. In the later assemblies a multi-chamber scanning system was used to measure fission rates at a large number of points in the core. Various simplifications were made in developing calculational models to analyse the measurements, although information is also provided giving the full details of the core loadings. Simplifications include corrections to replace the ZEBRA control rods by standard core elements and replacing the slightly different plutonium plates by a single one. These differences result in small differences in core height for the different elements and a correction is also made for this. In the earlier cores equivalent homogeneous compositions were derived and cylindrical (and even spherical) equivalent models derived. Later the plates were represented explicitly in the cell calculations used to derive homogeneous cell-averaged cross-sections for whole reactor calculations, including representation of the cladding materials (in a three dimensional, XYZ representation). NEA-1661/02: April 2006: this is the DVD version

  17. Additions and amendments to the bird and mammal lists of the Mountain Zebra National Park

    Directory of Open Access Journals (Sweden)

    P. J Bronkhorst

    1981-01-01

    Full Text Available The following account updates and amends various previous publications dealing with the birds and mammals of the Mountain Zebra National Park (MZNP. In the case of birds, Roberts' Birds of South Africa numbers are used.

  18. Additions and amendments to the bird and mammal lists of the Mountain Zebra National Park

    OpenAIRE

    P. J Bronkhorst; J. H. Grobler

    1981-01-01

    The following account updates and amends various previous publications dealing with the birds and mammals of the Mountain Zebra National Park (MZNP). In the case of birds, Roberts' Birds of South Africa numbers are used.

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

    OpenAIRE

    Songhua Wang; Congshu Liao; Fengling Li; Shaoyi Liu; Wei Meng; Dongfeng Li

    2014-01-01

    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 r...

  20. Zebra pattern in CT during arterial portography analysis of associated factors

    International Nuclear Information System (INIS)

    To analyze the factors associated with the zebra pattern in CT during arterial portography(CTAP). In 275 CTAP procedures, the factors associated with the zebra pattern, such as laminar flow in the portal vein, the presence of liver cirrhosis, the artery selected for CTAP, location of the catheter tip in the superior mesenteric artery(SMA), splenic volume, and the existence of an aberrant right hepatic artery(RHA) emerging from the SMA were analyzed. In 106 of 275 procedures (38.5%), a zebra pattern was apparent. Portal venous laminal flow was seen in 92% of procedures in the group with this pattern and in 63% in the group without it. Eighty-three of 235 procedures (35.3%) in which the SMA was injected and 23 of 40(57.5%) involving splenic artery injection showed the zebra pattern. In 22 of 35(62.8%) in which the catheter tip was located in the distal SMA and 61 of 200(30.5%) in which this was at a proximal site, the zebra pattern was evident. Mean splenic volume was less in the group with the zebra pattern. The effect on the zebra pattern of liver cirrhosis and an aberrant RHA emerging from the SMA was not statistically significant. In CTAP, the incidence of the zebra pattern was 38.6%, and was related to laminal flow in the portal vein. The pattern is frequently seen in CTAP involving contrast injection via the splenic artery, distal location of a catheter tip in the SMA, and small splenic volume

  1. The gaping reaction and the development of fear in young zebra finches (Taeniopygia guttata castanotis)

    OpenAIRE

    Bischof, Hans-Joachim; Lassek, Reinhard

    1985-01-01

    Responses of young zebra finches towards different stimuli were tested between hatching and 20 days of age. The stimuli applied were: tactile stimulation with a stick, acoustic stimulation from a loudspeaker playing begging calls of other nestlings, and stuffed dummies of zebra finches and Bengalese finches as visual stimuli. Tactile and acoustic stimuli resulted in gaping responses from the first day of life. Visual stimuli elicited gaping from about day 10 or 11, 4 days after the opening of...

  2. Reconstruction of physiological instructions from Zebra finch song

    Science.gov (United States)

    Perl, Yonatan Sanz; Arneodo, Ezequiel M.; Amador, Ana; Goller, Franz; Mindlin, Gabriel B.

    2011-11-01

    We reconstruct the physiological parameters that control an avian vocal organ during birdsong production using recorded song. The procedure involves fitting the time dependent parameters of an avian vocal organ model. Computationally, the model is implemented as a dynamical system ruling the behavior of the oscillating labia that modulate the air flow during sound production, together with the equations describing the dynamics of pressure fluctuations in the vocal tract. We tested our procedure for Zebra finch song with, simultaneously recorded physiological parameters: air sac pressure and the electromyographic activity of the left and right ventral syringeal muscles. A comparison of the reconstructed instructions with measured physiological parameters during song shows a high degree of correlation. Integrating the model with reconstructed parameters leads to the synthesis of highly realistic songs.

  3. Improving production of Zebra Fish Embryos in the lab

    DEFF Research Database (Denmark)

    Thomsen, Jens Peter; Adu, Robert Ohene

    2011-01-01

    The utilization of fish embryos in toxicity testing of hazardous chemicals has recently been adopted in order to satisfy stricter rules and regulations related to using adult animals in toxicity testing. This paper presents optimising steps towards improving zebra fish embryo production in the laboratory. Culture conditions were maintained in the aquaria as stipulated in the OECD draft proposal for a new guideline on fish embryo tests. Furthermore, a sequence of steps were adopted and followed to improve upon previous work done in the lab in 2006. About 200 eggs were produced in one spawn trap within an hour of onset of light, an improvement over the 50-60 eggs produced in the previous work. This result demonstrates that with the right culture conditions and proper optimisation of procedure the required number of embryos needed for toxicity testing can be obtained.

  4. 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.

  5. IMPACT OF OXYGEN CONCENTRATION ON ZEBRA MUSSEL MORTALITY

    International Nuclear Information System (INIS)

    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

  6. 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.

  7. 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. PMID:24112626

  8. Artificial grammar learning in zebra finches and human adults: XYX versus XXY.

    Science.gov (United States)

    Chen, Jiani; van Rossum, Danielle; ten Cate, Carel

    2015-01-01

    Abstracting syntactic rules is critical to human language learning. It is debated whether this ability, already present in young infants, is human- and language specific or can also be found in non-human animals, indicating it may arise from more general cognitive mechanisms. Current studies are often ambiguous and few have directly compared rule learning by humans and non-human animals. In a series of discrimination experiments, we presented zebra finches and human adults with comparable training and tests with the same artificial stimuli consisting of XYX and XXY structures, in which X and Y were zebra finch song elements. Zebra finches readily discriminated the training stimuli. Some birds also discriminated novel stimuli when these were composed of familiar element types, but none of the birds generalized the discrimination to novel element types. We conclude that zebra finches show evidence of simple rule abstraction related to positional learning, suggesting stimulus-bound generalization, but found no evidence for a more abstract rule generalization. This differed from the human adults, who categorized novel stimuli consisting of novel element types into different groups according to their structure. The limited abilities for rule abstraction in zebra finches may indicate what the precursors of more complex abstraction as found in humans may have been like. PMID:25015135

  9. 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...

  10. Some aspects of fast reactor operation studied in Zebra

    International Nuclear Information System (INIS)

    Four aspects of the fast reactor operating cycle that have been experimentally investigated in Zebra are described. Sensitive radiochemical techniques for measuring the capture rates in 241Am and 243Am leading to 242Cm and 244Cm have been applied to samples irradiated in spectra characteristic of PFR and of a commercial-size reactor. The derived cross sections are compared with those predicted using recent evaluations. Gamma activities induced in a range of elements of potential significance to contamination of the primary circuit in core and axial-breeder locations have been determined by standardised liquid-source counting techniques. Samples of fuel-clad and subassembly-wrapper alloys have also been examined. Results are compared with predictions using currently-recommended cross-sections. The energy release by B-particles from fission products of 235U and 239Pu following a 105-second irradiation has been measured over a cooling period of 1 year using a catcher-foil technique and a plastic scintillation detector. Comparisons with summation-code predictions are presented. The formation of plutonium in a radial breeder has been simulated by replacing UO2 plates by PuO2/UO2 to give an average level of 2% Pu/U. The influence of this enrichment on the reaction rates of 235U, and 238U and 239Pu was measured by foil activation methods. Comparisons with diffusion and transport-theory calculations are made. (author)

  11. Food preference and copying behaviour in zebra finches, Taeniopygia guttata.

    Science.gov (United States)

    Guillette, Lauren M; Morgan, Kate V; Hall, Zachary J; Bailey, Ida E; Healy, Susan D

    2014-11-01

    As a social species zebra finches might be expected to copy the food choices of more experienced conspecifics. This prediction has been tested previously by presenting observers with two demonstrator birds that differ in some way (e.g., sex, familiarity), each feeding on a different colour food source. However, if the observer subsequently exhibits a preference, it is unclear whether it has copied the choice of one demonstrator or avoided the choice of the other. Furthermore, this choice may actually be influenced by pre-existing preferences, a potential bias that is rarely tested. Here we examine whether apparent copying or avoidance can be explained by pre-existing preferences. In Experiment 1, observers had the opportunity to watch a conspecific forage from one of the two differently coloured food hoppers. In Experiment 2, the observers did not have this opportunity. In both experiments observers were subsequently tested for their food hopper preference and all but one preferred one colour over the other. In Experiment 1 some observers showed evidence for copying, while others seemed to avoid the colour preferred by the demonstrator. In Experiment 2 females generally preferred the white hopper. Pre-existing colour preferences could, therefore, explain the apparent copying/avoidance we observed. This article is part of a Special Issue entitled: Cognition in the wild. PMID:24797456

  12. Drinking Songs: Alcohol Effects on Learned Song of Zebra Finches

    Science.gov (United States)

    Olson, Christopher R.; Owen, Devin C.; Ryabinin, Andrey E.; Mello, Claudio V.

    2014-01-01

    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. PMID:25536524

  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. The Zebra Stripes of the Atacama Desert: Geomorphic Evidence of Quaternary Climate Changes

    Science.gov (United States)

    Owen, J. J.; Amundson, R.; Dietrich, W. E.; Nishiizumi, K.; Finkel, R. C.; Chong, G.

    2009-12-01

    Some hillslopes in the hyperarid region of the Atacama Desert of northern Chile have distinct, contour-parallel bands of sorted surface gravels which we call “zebra stripes” (due to the contrast between the darkly varnished gravels and the light-colored, salt-rich soil). How and when the zebra stripes formed are perplexing questions, particularly since no recorded rainfall seems capable of producing such features. Using GoogleEarth, satellite imagery, field observations, and cosmogenic radionuclides, we have made the first quantitative observations of zebra stripes in order to determine the mechanism and timing of their formation. Possible formation mechanisms include soil shrinking and swelling, seismic shaking, and overland flow, but field observations suggest that overland flow is the most likely. However, calculations based on soil observations and sprinkling experiments on one hillslope suggest that the critical precipitation required to mobilize gravels is much higher than any storm in the historic record. Based on cosmogenic 10Be concentrations in gravels and bedrock, as well as salt deposition rates and concentrations in the soils, we propose that the salt-rich soils began accumulating >0.5-1 Ma, but that the zebra stripes formed later (103-105 ya) on salt-cemented, low-permeability soil. The preservation of the zebra stripe pattern to the present day attests to the prolonged hyperaridity of the Atacama and to the profound climatic change that occurred sometime between the late Pliocene and early Pleistocene. Our work provides initial constraints on zebra stripe formation and timing which may help interpretation of surface deposits in other hyperarid regions on Earth and other planets.

  15. Quantitative genetics and behavioural correlates of digit ratio in the zebra finch

    OpenAIRE

    Forstmeier, Wolfgang

    2005-01-01

    A recent study on a captive zebra finch population suggested that variation in digit ratio (i.e. the relative length of the second to the fourth toe) might be an indicator of the action of sex steroids during embryo development, as is widely assumed for human digits. Zebra finch digit ratio was found to vary with offspring sex, laying order of eggs within a clutch, and to predict aspects of female mating behaviour. Hence, it was proposed that the measurement of digit ratio would give insights...

  16. Proper care, husbandry, and breeding guidelines for the zebra finch, Taeniopygia guttata.

    Science.gov (United States)

    Olson, Christopher R; Wirthlin, Morgan; Lovell, Peter V; Mello, Claudio V

    2014-12-01

    The zebra finch Taeniopygia guttata castanotis is a songbird commonly used in the laboratory, particularly for studies of vocal learning, neurobiology, and physiology. Within the laboratory, it is important to adopt careful husbandry practices that allow for normal development of the birds. For example, their song is a learned trait, passed culturally from adult males to juveniles, and thus its learning can be influenced by the health and social conditions of the birds present in the laboratory. Here we present guidelines for the successful maintenance and breeding of captive zebra finches. PMID:25342067

  17. Spatially and Spectrally Resolved Observations of a Zebra Pattern in Solar Decimetric Radio Burst

    OpenAIRE

    Chen, Bin; Bastian, Timothy S.; Gary, Dale E.; Jing, Ju

    2011-01-01

    We present the first interferometric observation of a zebra-pattern radio burst with simultaneous high spectral (~ 1 MHz) and high time (20 ms) resolution. The Frequency-Agile Solar Radiotelescope (FASR) Subsystem Testbed (FST) and the Owens Valley Solar Array (OVSA) were used in parallel to observe the X1.5 flare on 14 December 2006. By using OVSA to calibrate the FST the source position of the zebra pattern can be located on the solar disk. With the help of multi-wavelengt...

  18. Pathology and immunohistochemistry of papillomavirus-associated cutaneous lesions in Cape mountain zebra, giraffe, sable antelope and African buffalo in South Africa

    Scientific Electronic Library Online (English)

    J H, Williams; E van, Dyk; P J, Nel; E, Lane; E Van, Wilpe; R G, Bengis; L-M de, Klerk-Lorist; J, van Heerden.

    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 presented with a solitary large lesion just proximal to the right hind hoof, which recurred after excision, and was BPV-1 positive by RT-PCR. Other wart-like growths were present elsewhere on the body. The Cape mountain zebra either succumbed from their massive lesions or were euthanased or removed from the herd because of them. The lesions were BPV-1 and/or -2 positive by RT-PCR. The buffalo lesions were wart-like papillomatous projections in the inguinal and udder region. Stratum granulosum cells that stained immunohistochemically positive in the various species appeared koilocyte-like, as described in human papillomaviral lesions.

  19. 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. van Heerden

    2012-04-01

    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 presented with a solitary large lesion just proximal to the right hind hoof, which recurred after excision, and was BPV-1 positive by RT-PCR. Other wart-like growths were present elsewhere on the body. The Cape mountain zebra either succumbed from their massive lesions or were euthanased or removed from the herd because of them. The lesions wereBPV-1 and/or -2 positive byRT-PCR. The buffalo lesions were wart-like papillomatous projections in the inguinal and udder region. Stratum granulosum cells that stained immunohistochemically positive in the various species appeared koilocyte-like, as described in human papillomaviral lesions.

  20. Developmental stress increases reproductive success in male zebra finches.

    Science.gov (United States)

    Crino, Ondi L; Prather, Colin T; Driscoll, Stephanie C; Good, Jeffrey M; Breuner, Creagh W

    2014-11-22

    There is increasing evidence that exposure to stress during development can have sustained effects on animal phenotype and performance across life-history stages. For example, developmental stress has been shown to decrease the quality of sexually selected traits (e.g. bird song), and therefore is thought to decrease reproductive success. However, animals exposed to developmental stress may compensate for poor quality sexually selected traits by pursuing alternative reproductive tactics. Here, we examine the effects of developmental stress on adult male reproductive investment and success in the zebra finch (Taeniopygia guttata). We tested the hypothesis that males exposed to developmental stress sire fewer offspring through extra-pair copulations (EPCs), but invest more in parental care. To test this hypothesis, we fed nestlings corticosterone (CORT; the dominant avian stress hormone) during the nestling period and measured their adult reproductive success using common garden breeding experiments. We found that nestlings reared by CORT-fed fathers received more parental care compared with nestlings reared by control fathers. Consequently, males fed CORT during development reared nestlings in better condition compared with control males. Contrary to the prediction that developmental stress decreases male reproductive success, we found that CORT-fed males also sired more offspring and were less likely to rear non-genetic offspring compared with control males, and thus had greater overall reproductive success. These data are the first to demonstrate that developmental stress can have a positive effect on fitness via changes in reproductive success and provide support for an adaptive role of developmental stress in shaping animal phenotype. PMID:25297860

  1. The Zebra Battery: a South African contender for electric vehicle application Die Zebra-battery - ’n Suid-Afrikaanse aanspraakmaker in die elektriesevoertuigbedryf

    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.Die Zebra-battery is ’n sterk aanspraakmaker daarop om voor die einde van die eeu wêreldwyd die energiebron van elektriese voertuie te word. Dit is 'n Suid-Afrikaanse ontwikkeling wat by die Wetenskaplike en Nywerheidnavorsingsraad (WNNR begin het en tans deur die Anglo American Korporasie van S.A. en die Duitse maatskappy, A.E.G., bestuur word. Die selreaksie vind plaas tussen gewone tafelsout en nikkelmetaal tydens die laaiproses om natriummetaal en nikkelchloried te vorm.

  2. Zebra: Searching for Rare Diseases : A Case of Task-Based Search in the Medical Domain

    DEFF Research Database (Denmark)

    Dragusin, Radu; Petcu, Paula

    2012-01-01

    Task-based search addresses situations where standard off-the-shelf Information Retrieval (IR) technology may not suffice to satisfy users in their tasks. In these situations, IR systems should be tailored to the user’s task-specific needs and requirements. One such task is searching for rare 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 to be a useful and competitive tool for clinicians. In this work, we extend Zebra’s functionalities to optimise the task of medical diagnosis through search as follows: we add the option of grouping retrieved documents into clusters based on disease name occurrence, and we offer a ‘disease-ranking’ option, in addition to the standard ‘document-ranking’ option. This paper presents and discusses these functionalities.

  3. 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.

  4. A Generalizability Analysis of Subjective Personality Assessments in the Stumptail Macaque and the Zebra Finch.

    Science.gov (United States)

    Figueredo, Aurelio Jose; And Others

    1995-01-01

    Two longitudinal studies involving 29 raters concerning the construct validity, temporal stability, and interrater reliability of the latent common factors underlying subjective assessments by human raters of personality traits in the stumptail macaque and the zebra finch illustrate the use of generalizability analysis to test prespecified…

  5. The Quantitative Ethology of the Zebra Finch: A Study in Comparative Psychometrics.

    Science.gov (United States)

    Figueredo, Aurelio Jose; And Others

    1992-01-01

    A quantitative ethogram was developed for the zebra finch, using one-zero focal animal sampling on an ethologically comprehensive checklist of 52 behavioral items, and it was assessed for interobserver reliability and construct validity. Applying the quantitative methods of psychometrics allows verification of ethological theory and testing of…

  6. Spatially and Spectrally Resolved Observations of a Zebra Pattern in Solar Decimetric Radio Burst

    CERN Document Server

    Chen, Bin; Gary, Dale E; Jing, Ju

    2011-01-01

    We present the first interferometric observation of a zebra-pattern radio burst with simultaneous high spectral (~ 1 MHz) and high time (20 ms) resolution. The Frequency-Agile Solar Radiotelescope (FASR) Subsystem Testbed (FST) and the Owens Valley Solar Array (OVSA) were used in parallel to observe the X1.5 flare on 14 December 2006. By using OVSA to calibrate the FST the source position of the zebra pattern can be located on the solar disk. With the help of multi-wavelength observations and a nonlinear force-free field (NLFFF) extrapolation, the zebra source is explored in relation to the magnetic field configuration. New constraints are placed on the source size and position as a function of frequency and time. We conclude that the zebra burst is consistent with a double-plasma resonance (DPR) model in which the radio emission occurs in resonance layers where the upper hybrid frequency is harmonically related to the electron cyclotron frequency in a coronal magnetic loop.

  7. The Complete Genome Sequence of ‘Candidatus Liberibacter solanacearum’, the Bacterium Associated with Potato Zebra Chip Disease

    OpenAIRE

    Lin, Hong; Lou, Binghai; Glynn, Jonathan M; Doddapaneni, Harshavardhan; Civerolo, Edwin L.; Chen, Chuanwu; Duan, Yongping; ZHOU, LIJUAN; Vahling, Cheryl M.

    2011-01-01

    Zebra Chip (ZC) is an emerging plant disease that causes aboveground decline of potato shoots and generally results in unusable tubers. This disease has led to multi-million dollar losses for growers in the central and western United States over the past decade and impacts the livelihood of potato farmers in Mexico and New Zealand. ZC is associated with ‘Candidatus Liberibacter s...

  8. Annotated Check List of the Spiders (Araneae of the Mountain Zebra National Park

    Directory of Open Access Journals (Sweden)

    Anna S. Dippenaar-Schoeman

    1988-10-01

    Full Text Available A preliminary check list of the spider fauna of the Mountain Zebra National Park is given. Sixteen families, comprising 29 genera and 32 species, are recorded. Observations on the distribution, diagnostic morphology and behaviour of 15 species are given.

  9. Infestation of research zebra finch colony with 2 novel mite species.

    Science.gov (United States)

    Siddalls, Monica; Currier, Timothy A; Pang, Jassia; Lertpiriyapong, Kvin; Patterson, Mary M

    2015-02-01

    A zebra finch (Taeniopygia guttata) housed in a neuroscience laboratory was observed to have numerous feather mites. Subsequently, similar mites were found on other birds in the animal facility and research space. The most abundant mite was a novel, undescribed species in the genus Neocheyletiella. Whereas known Neocheyletiella mites have previously been characterized as skin parasites of various birds worldwide, the species on the zebra finches is unique because it lives and builds nests in the feathers. Infrequent specimens of a 'true' feather mite, a new species of Megninialges, were present also. Although multiple treatments using a pyrethrin spray were effective in eradicating the mites, topical ivermectin later was found to be more efficacious, better tolerated by the birds, and less labor intensive. This case highlights the general dearth of information regarding ectoparasites in zebra finches, even though these are the most frequently used songbirds in biomedical research. The mite epizootic also underscores the diverse pathogens possible in zebra finches that arrive from outside sources and why ongoing health monitoring of finch colonies is warranted. PMID:25730757

  10. 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...

  11. 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, Australia. I…

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

    Energy Technology Data Exchange (ETDEWEB)

    Kotler, S.R. [ARD Environmental, Inc., Columbia, MD (United States); Mallen, E.C. [Indiana Michigan Power Co./Cook Nuclear Plant, Bridgman, MI (United States); Tamms, K.M.

    1995-06-01

    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.

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

    International Nuclear Information System (INIS)

    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 Setion 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

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

    International Nuclear Information System (INIS)

    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 equipmstrict 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

  15. 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. PMID:25910461

  16. Assessing short- and long-term repeatability and stability of personality in captive zebra finches using longitudinal data

    OpenAIRE

    David, Morgan; Auclair, Yannick; Cezilly, Frank

    2012-01-01

    Assessing behavioural consistency is crucial to understand the evolution of personality traits. In the present study we examined the short- and long-term repeatability and stability of two unrelated personality traits—exploratory tendencies and struggling rate—using captive female zebra finches (Taeniopygia guttata). We performed two experimental sessions of behavioural tests with a seven-month interval, which represents up to one quarter of a zebra finch's life expectancy. We showed that...

  17. Differential responsiveness in brain and behavior to sexually dimorphic long calls in male and female zebra finches.

    Science.gov (United States)

    Gobes, Sharon M H; Ter Haar, Sita M; Vignal, Clémentine; Vergne, Amélie L; Mathevon, Nicolas; Bolhuis, Johan J

    2009-10-01

    In zebra finches (Taeniopygia guttata), as in most other songbird species, there are robust sex differences in brain morphology and vocal behavior. First, male zebra finches have larger song system nuclei--involved in sensorimotor learning and production of song--than females. Second, male zebra finches learn their song from a tutor, whereas female zebra finches develop a learned preference for the song of their father but do not sing themselves. Third, female zebra finches produce an unlearned "long call," while males learn their long call (which is different from that of females) from their song tutor. We investigated behavioral and molecular neuronal responsiveness to this sexually dimorphic communication signal. Behavioral responsiveness was quantified by measuring the number of calls and approaches in response to calls that were broadcast from a speaker. We quantified neuronal activation by measuring the number of neurons expressing Zenk, the protein product of the immediate early gene ZENK, in a number of different forebrain regions in response to male calls, to female calls, or to silence. In both sexes female calls evoked more calls and approaches than male calls. There was significantly greater Zenk expression in response to female calls compared to silence in the caudomedial nidopallium, caudomedial mesopallium, and the hippocampus in females, but not in males. Thus, male and female zebra finches both show a behavioral preference for female calls, but differential neuronal activation in response to sexually dimorphic calls. PMID:19637285

  18. Comparative genomic analysis of the zebra finch degradome provides new insights into evolution of proteases in birds and mammals

    Directory of Open Access Journals (Sweden)

    López-Otín Carlos

    2010-04-01

    Full Text Available Abstract Background The degradome -the complete repertoire of proteases in an organism- is involved in multiple key biological and pathological processes. Previous studies in several organisms have yielded sets of curated protease sequences which may be used to characterize the degradome in a novel genome by similarity. Differences between degradomes can then be related to physiological traits of the species under study. Therefore, the sequencing of the zebra finch genome allows the comparison between the degradomes of mammals and birds and may help to understand the biological peculiarities of the zebra finch. Results A set of curated protease sequences from humans and chicken was used to predict the sequences of 460 protease and protease-like genes in the zebra finch genome. This analysis revealed important differences in the evolution of mammalian and bird degradomes, including genomic expansions and deletions of caspases, cytotoxic proteases, kallikreins, matrix metalloproteases, and trypsin-like proteases. Furthermore, we found several zebra finch-specific features, such as duplications in CASP3 and BACE, and a large genomic expansion of acrosin. Conclusions We have compared the degradomes of zebra finch, chicken and several mammalian species, with the finding of multiple differences which illustrate the evolution of the protease complement of these organisms. Detailed analysis of these changes in zebra finch proteases has shown that they are mainly related to immunological, developmental, reproductive and neural functions.

  19. Genomic and neural analysis of the estradiol-synthetic pathway in the zebra finch

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    London Sarah E

    2010-04-01

    Full Text Available Abstract Background Steroids are small molecule hormones derived from cholesterol. Steroids affect many tissues, including the brain. In the zebra finch, estrogenic steroids are particularly interesting because they masculinize the neural circuit that controls singing and their synthesis in the brain is modulated by experience. Here, we analyzed the zebra finch genome assembly to assess the content, conservation, and organization of genes that code for components of the estrogen-synthetic pathway and steroid nuclear receptors. Based on these analyses, we also investigated neural expression of a cholesterol transport protein gene in the context of song neurobiology. Results We present sequence-based analysis of twenty steroid-related genes using the genome assembly and other resources. Generally, zebra finch genes showed high homology to genes in other species. The diversity of steroidogenic enzymes and receptors may be lower in songbirds than in mammals; we were unable to identify all known mammalian isoforms of the 3?-hydroxysteroid dehydrogenase and 17?-hydroxysteroid dehydrogenase families in the zebra finch genome assembly, and not all splice sites described in mammals were identified in the corresponding zebra finch genes. We did identify two factors, Nobox and NR1H2-RXR, that may be important for coordinated transcription of multiple steroid-related genes. We found very little qualitative overlap in predicted transcription factor binding sites in the genes for two cholesterol transport proteins, the 18 kDa cholesterol transport protein (TSPO and steroidogenic acute regulatory protein (StAR. We therefore performed in situ hybridization for TSPO and found that its mRNA was not always detected in brain regions where StAR and steroidogenic enzymes were previously shown to be expressed. Also, transcription of TSPO, but not StAR, may be regulated by the experience of hearing song. Conclusions The genes required for estradiol synthesis and action are represented in the zebra finch genome assembly, though the complement of steroidogenic genes may be smaller in birds than in mammals. Coordinated transcription of multiple steroidogenic genes is possible, but results were inconsistent with the hypothesis that StAR and TSPO mRNAs are co-regulated. Integration of genomic and neuroanatomical analyses will continue to provide insights into the evolution and function of steroidogenesis in the songbird brain.

  20. Sobre la validez taxonómica de Epithemia Zebra var. Elongata (Epithemiaceae, Bacillariophyceae

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    Gabriela Gorritti

    2000-01-01

    Full Text Available Gorritti, G., Sala, S. E. & Guerrero, J. M. 2000. Sobre la validez taxonómica de Epithemiazebra var. elongata (Epithemiaceae, Bacillariophyceae. Darwiniana 38(3-4: 285-289.Se revisaron materiales de Epithemia zebra var. elongata Grunow ex Frenguelli para establecer lavalidez de este taxón. Se estudiaron con microscopio óptico y electrónico de barrido, ejemplares de lacolección Frenguelli y otros recientemente coleccionados en Tierra del Fuego . El análisis de la variaciónpoblacional de los caracteres morfológicos y morfométricos, y la comparación con los taxones afines:Epithemia adnata (Kützing Brébisson y E. adnata var. minor (Peragallo & Héribaud Patrick, demostróque no existen diferencias entre ellos por lo que E. zebra var. elongata debe ser considerada sinónimo deE. adnata

  1. Colour bands, dominance, and body mass regulation in male zebra finches (Taeniopygia guttata)

    OpenAIRE

    Cuthill, I C; HUNT, S; Cleary, C; Clark, C.

    1997-01-01

    The arbitrary assignment of different coloured leg bands to zebra finches (Taeniopygia guttata) has profound effects on mate preference, reproductive success, mortality rates, parental investment and sex ratio. Choice chamber experiments indicate that the effect is mediated by altered attractiveness to members of the opposite sex. Effects on intrasexual dominance are more equivocal. We present two experiments which demonstrate significant effects of band colour on behavioural dominance (red b...

  2. Pharyngeal teeth of the freshwater drum (Aplodinotus grunniens) a predator of the zebra mussel (Dreissena polymorpha)

    Science.gov (United States)

    French, John R. P., III

    1997-01-01

    The morphology of pharyngeal teeth of freshwater drum (Aplodinotus grunniens) was studied to determine changes that occur during growth of drum that may relate to consumption of zebra mussel (Dreissena polymorpha) by larger fish. Pharyngeal teeth were of three types. Cardiform teeth were replaced by villiform teeth, which were replaced by molariform teeth as the size class of drum increased. Molariform teeth comprised over 85% of total surface area of dentition in fish 265 mm long.

  3. Visual wulst influences on flash evoked responses in the ectostriatum of the zebra finch

    OpenAIRE

    Engelage, Ju?rgen; Bischof, Hans-joachim

    1994-01-01

    Anatomical data suggest that visual information from the thalamofugal pathway contributes to visual processing in the tectofugal pathway. We addressed the question of the functionality of anatomically described connections to the visual system of a laterally eyed bird, the zebra finch. The study shows the contribution of visual wulst efferents to visual processing in the ectostriatum by recordings of visually evoked slow field potentials. Suppression of visual wulst activity resulted in a sel...

  4. Same-sex partner preference in zebra finches: pairing flexibility and choice.

    Science.gov (United States)

    Tomaszycki, Michelle L; Zatirka, Brendon P

    2014-11-01

    This study examined flexibility and choice in same-sex pair-bonding behavior in adult zebra finches (Taeniopygia guttata). Zebra finches form life-long monogamous relationships and extra pair behavior is very low, making them an ideal species in which to study same-sex pairing. We examined same-sex behaviors using both semi-naturalistic choice paradigms and skewed sex ratios. In the first experiment, we allowed zebra finches to pair in aviaries with equal sex ratios as part of multiple experiments. On average, 6.4% (N = 78) of unmanipulated pairs were same-sex: all but one was female-female. In a second experiment, we identified pairs from same-sex cages and selected 20 total same-sex pairs (10 of each sex). We then gave pairs a chance to court and pair with members of the opposite sex and observed their behavior for three days. Females did not retain their partner, but most paired with males. In contrast, some males did retain their partner. Similarly, females were more likely to engage in pairing behaviors with males than with their partners or other females whereas males were equally likely to engage in same-sex and opposite-sex pairing behaviors. These findings suggest that same-sex partnerships in zebra finches can be facultative, based on the sex ratio of the group in which they live, but can also be a choice, when opportunities to pair with opposite-sex individuals are possible. Furthermore, it is possible that females are more flexible in this choice of same-sex partnerships than are males. PMID:25190500

  5. EFFECTS OF ORGANOPHOSPHATES ON ACUTE POISONING AND ACETYL CHOLINESTERASE INHIBITION IN ZEBRA FISH

    OpenAIRE

    Th Mv, Sukirtha Usharani

    2013-01-01

    Organophosphates (Ops.) are the most widely used insecticides available today. These are a group of insecticides used in chemical sprays to kill bugs, and insects in orchards, vineyards, vegetables and cereal crops. The present study examined effects of the pesticide Methyl parathion, Dichlorvos and Chlorpyrifos on adult zebra fish were exposed to various concentrations (5, 10 & 25mg/L) for 24 and 48hrs acute toxic study. Chlorpyrifos showed mortality in all concentrations and Methyl para...

  6. New records of 43 spider species from the Mountain Zebra National Park, South Africa (Arachnida: Araneae)

    OpenAIRE

    Dippenaar-schoeman, A. S.

    2006-01-01

    This study forms part of the South African National Survey of Arachnida (SANSA), initiated in 1997 with the main aim to create an inventory of the arachnid fauna of South Africa (Dippenaar-Schoeman & Craemer 2000). One of the objectives of SANSA is to assess the number of arachnid species presently protected in conserved areas in the country. Check lists of spiders are now available for three national parks, three nature reserves and a conservancy. These areas include: Mountain Zebra ...

  7. 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...

  8. Preparation and evaluation of biocide-loaded particles to control the biofouling zebra mussel, Dreissena polymorpha

    OpenAIRE

    Costa, R; Aldridge, D. C.; Moggridge, G. D.

    2011-01-01

    The freshwater zebra mussel Dreissena polymorpha is a powerful biofouling bivalve, which has tremendous impact on industrial facilities whose operation depends on the intensive use of freshwater, such as waterworks and power stations. The control of the pest in industrial environments remains a major challenge due to low selectivity over non-target organisms and the expense of the large quantities of biocides required. A novel delivery technique involving the encapsulation of a toxin within h...

  9. 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.

  10. Zebra mussels (Dreissena polymorpha) as a biomonitoring tool for Sr90 contamination

    International Nuclear Information System (INIS)

    Due to their efficient filtration capabilities, zebra mussels (Dreissena polymorpha) are effective biomonitors of a wide range of environmental pollutants. In this study we test the suitability of zebra mussels as bio-monitors of Sr90 contamination around a nuclear power station situated at Gentilly, Quebec along the St. Lawrence River. Based on the latest emission data which indicated negligible contributions of Sr90 to the river, we hypothesize that dreissenids collected at sites upstream (Montreal), at the station and downstream from the station (Donnacona) would show no significant differences in shell concentrations of Sr90. Zebra mussel shell concentrations of Sr90 were in the order of 0.02 pCi/g at Gentilly, 0.04 pCi/g at Montreal and 0.03 pCi/g at Donnacona, all values being below the limit of detection of the analytical method. We also considered the implication of Sr90 contamination to higher trophic levels in the food chain. (Author)

  11. Investigation of Acute Toxicity Diazinon, Deltamethrin, Butachlor and pretilachlor on Zebra Cichlid (Cryptoheros nigrofasciatus

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    Ali Sadeghi

    2014-06-01

    Full Text Available Background: The presence of pesticide due to the huge demand for agricultural purposes is very prevalent in surface waters of Iran. These pesticides could finally accumulate in aquatic ecosystems and have been proved to have toxic effects on aquatic animals. The aim of this study was to assess the acute toxicity of Diazinon, Deltamethrin, Butachlor and Pretilachlor on Zebra Cichlid (Cryptoheros nigrofasciatus. Methods: Fish samples were exposed to different concentrations of Diazinon (60% (0, 2, 4, 8, 16 and 32 ppm, Deltamethrin (2.5% (0, 0.02, 0.04, 0.10, 0.20 and 0.40 ppm, butachlor (60% (0, 2, 4, 8, 16 and 32 ppm and pretilachlor (50% (0, 5, 10, 20, 30 and 40 ppm for 96 h within the 100 L glass aquaria and cumulative mortality of Zebra Cichlid fish was calculated in 24-h interval. Results: The very low LC50 obtained for diazinon (5.06±0.37 ppm, deltamethrin (0.15±0.39 ppm, butachlor (8.93±0.26 ppm and pretilachlor (20.72±0.58 ppm indicated that these are highly toxic chemicals. Conclusion: Our results demonstrate that deltamethrin and pretilachlor had the lowest and highest rate of mortality on the Zebra Cichlid respectively.

  12. STUDY ON EMBRYO DEVELOPMENT IN ZEBRA FISH (Danio rerio DEPENDING ON DIFFERENT pH LEVELS

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    MIHAELA B?DILI??

    2013-12-01

    Full Text Available The aim of this paper is to emphasize the main aspects of the ways in whichdifferent pH levels influence the development of zebra fish (Danio rerio embryos.During the experiments there have been used 6 variants with different pH levels inorder to monitor the development of zebra fish embryos in 40 ml Nunk culturedishes at optimum density (1 embryo/ 3 ml and at an optimal temperature of28.5oC.It could be noticed that most embryos died in a pH=6 medium (70%. This meansthat such a medium is not suitable to embryo’s development. For the controlvariant (pH=7 it has been recorded the lowest mortality rate of only 23% and inthe case of other variants the mortality was of 30-40%.The studies of the pH influence upon the zebra fish embryo development haveunderlined the fact that little digressions from the optimal conditions can led toirreversible modifications within the roe which sometimes are even lethal.

  13. Zebra body myopathy is caused by a mutation in the skeletal muscle actin gene (ACTA1).

    Science.gov (United States)

    Sewry, C A; Holton, J L; Dick, D J; Muntoni, F; Hanna, M G

    2015-05-01

    We present follow up data on the original case of 'zebra body myopathy' published by Lake and Wilson in 1975. Pathological features in a second biopsy performed at the age of 29 years included a wide variation in fibre size, multiple split fibres, excess internal nuclei and endomysial connective tissue, rimmed vacuoles, accumulation of myofibrillar material and large 'wiped out' areas lacking stain for oxidative enzymes. The presence of nemaline rods and actin-like filaments in addition to small zebra bodies suggested ACTA1 as a candidate gene. This has been confirmed by the identification of a novel c.1043T.p.Leu348Gln mutation, which probably occurred de novo. This case illustrates that the myopathy associated with zebra bodies is part of the spectrum of myopathies associated with the ACTA1 gene. It also highlights that accumulation of actin filaments is not confined to severe neonatal ACTA1 cases and that progression of weakness can occur in congenital myopathies, as the patient is now wheelchair bound and can only stand with the aid of a walking frame. PMID:25747004

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

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    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 chromosomal fission, gene duplication and translocation in the history of the MHC in birds, and highlight striking differences in MHC structure and organization among avian lineages.

  15. 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…

  16. Genome-wide annotation and analysis of zebra finch microRNA repertoire reveal sex-biased expression

    Directory of Open Access Journals (Sweden)

    Luo Guan-Zheng

    2012-12-01

    Full Text Available Abstract Background MicroRNAs (miRNAs are small noncoding RNAs that regulate gene expression post-transcriptionally in a wide range of biological processes. The zebra finch (Taeniopygia guttata, an oscine songbird with characteristic learned vocal behavior, provides biologists a unique model system for studying vocal behavior, sexually dimorphic brain development and functions, and comparative genomics. Results We deep sequenced small RNA libraries made from the brain, heart, liver, and muscle tissues of adult male and female zebra finches. By mapping the sequence reads to the zebra finch genome and to known miRNAs in miRBase, we annotated a total of 193 miRNAs. Among them, 29 (15% are avian specific, including three novel zebra finch specific miRNAs. Many of the miRNAs exhibit sequence heterogeneity including length variations, untemplated terminal nucleotide additions, and internal substitution events occurring at the uridine nucleotide within a GGU motif. We also identified seven Z chromosome-encoded miRNAs. Among them, miR-2954, an avian specific miRNA, is expressed at significantly higher levels in males than in females in all tissues examined. Target prediction analysis reveals that miR-2954, but not other Z-linked miRNAs, preferentially targets Z chromosome-encoded genes, including several genes known to be expressed in a sexually dimorphic manner in the zebra finch brain. Conclusions Our genome-wide systematic analysis of mature sequences, genomic locations, evolutionary sequence conservation, and tissue expression profiles of the zebra finch miRNA repertoire provides a valuable resource to the research community. Our analysis also reveals a miRNA-mediated mechanism that potentially regulates sex-biased gene expression in avian species.

  17. Simple sequence repeats in zebra finch (Taeniopygia guttata expressed sequence tags: a new resource for evolutionary genetic studies of passerines

    Directory of Open Access Journals (Sweden)

    Birkhead Timothy R

    2007-02-01

    Full Text Available Abstract Background Passerines (perching birds are widely studied across many biological disciplines including ecology, population biology, neurobiology, behavioural ecology and evolutionary biology. However, understanding the molecular basis of relevant traits is hampered by the paucity of passerine genomics tools. Efforts to address this problem are underway, and the zebra finch (Taeniopygia guttata will be the first passerine to have its genome sequenced. Here we describe a bioinformatic analysis of zebra finch expressed sequence tag (EST Genbank entries. Results A total of 48,862 ESTs were downloaded from GenBank and assembled into contigs, representing an estimated 17,404 unique sequences. The unique sequence set contained 638 simple sequence repeats (SSRs or microsatellites of length ?20 bp and purity ?90% and 144 simple sequence repeats of length ?30 bp. A chromosomal location for the majority of SSRs was predicted by BLASTing against assembly 2.1 of the chicken genome sequence. The relative exonic location (5' untranslated region, coding region or 3' untranslated region was predicted for 218 of the SSRs, by BLAST search against the ENSEMBL chicken peptide database. Ten loci were examined for polymorphism in two zebra finch populations and two populations of a distantly related passerine, the house sparrow Passer domesticus. Linkage was confirmed for four loci that were predicted to reside on the passerine homologue of chicken chromosome 7. Conclusion We show that SSRs are abundant within zebra finch ESTs, and that their genomic location can be predicted from sequence similarity with the assembled chicken genome sequence. We demonstrate that a useful proportion of zebra finch EST-SSRs are likely to be polymorphic, and that they can be used to build a linkage map. Finally, we show that many zebra finch EST-SSRs are likely to be useful in evolutionary genetic studies of other passerines.

  18. Diversidad malacológica en una comunidad de Arca zebra (Mollusca: Bivalvia)en Chacopata, Estado Sucre, Venezuela

    Scientific Electronic Library Online (English)

    Antulio S., Prieto; Lilia J., Ruiz; Natividad, García; Miyosky, Alvarez.

    2001-06-01

    Full Text Available La diversidad malacológica de una comunidad submareal de Arca zebra se estudió, desde septiembre, 1990 hasta septiembre, 1991, en Chacopata, Estado Sucre, Venezuela. Se identificaron 40 especies (24 de bivalvos y 16 de gasterópodos). Los parámetros de diversidad en número de la comunidad fueron bajo [...] s (H` = 2.087 bits /ind., J` = 0.392, Simpson = 0.528) cuando se comparan con otros reportes de áreas tropicales. Los datos del número de individuos por especies con el rango conforman una línea recta ajustada por la serie logaritmica, con un índice de diversidad (a) de 5.66. Las máximas diversidades mensuales se observaron en septiembre, 1990 (1.63 bits/ind.) y julio, 1991 (1.60 bits/ind.), la mínima ocurrió en junio, 1991 (0.52 bits/ind.). De las 40 especies identificadas, la pepitona, Arca zebra fue la especie dominante en número (68.87 %) y en biomasa (72.34 %), seguida por Pinctada imbricata, Modiolus squamosus, Chama macerophyla y Anadara notabilis. Los gasterópodos predadores Phyllonotus pomum, Chicoreus brevifrons y Murex recurvirostris parecen tener relaciones tróficas con la especie dominante. La biomasa promedio total en peso húmedo con la concha (469.20 + 263 g m-2) es alta e indica que A. zebra, la especie dominante de rápido crecimiento, desempeña el papel más importante en la comunidad como un eficiente filtrador, que convierte el alimento planctónico en biomasa disponible, soportando una de las pesquerías más importantes de la región. Abstract in english The diversity of a subtidal epifaunal mollusk community was studied from September, 1990 to September, 1991 in Chacopata, Sucre State, Venezuela. There were 40 species (24 bivalves and 16 gastropods). The diversity indexes (H` = 2.087, J`=0.392, 1/D = 0.528) were low when compared with other tropica [...] l zones. Monthly diversity reached its maximum in September, 1990 (1.63 bits/ind.) and July, 1991 (1.60 bits/ind.); minimum diversity occurred in June, 1991 (0.52 bits/ind.). A Log series model applied to species abundance data showed a straight line with a diversity index a of 5.56. Of 40 species identified, the turkeywing Arca zebra was dominant (69 % in number of individuals and 72 % of biomass) followed by Pinctada imbricata, Modiolus squamosus, Chama macerophyla and Anadara notabilis. The predatory snails Phyllonotus pomum, Chicoreus brevifrons and Murex recurvirostris seemed to have trophic relationships with A. zebra. The total mean biomass in wet weight (469.20 + 263g m-2, shell included) was high which indicates that A. zebra, a species with a rapid growth rate, occupies a central role in the assemblage as an efficient filter feeder that converts planktonic food into available biomass, supporting one of the most important fisheries in Venezuela.

  19. Larvae of Chironomids (Insecta, Diptera) Encountered in the Mantle Cavity of Zebra Mussels, Dreissena polymorpha (Bivalvia, Dreissenidae)

    Science.gov (United States)

    Mastitsky, Sergey E.; Samoilenko, Vera M.

    2005-02-01

    The paper includes data on species composition of chironomid larvae which were encountered in the mantle cavity of zebra mussels (Dreissena polymorpha) within 7 waterbodies in the Republic of Belarus. All were found to be free-living species commonly present in periphyton and/or benthos. A long-term study of the seasonal dynamics of these larvae in Dreissena did not reveal any typical pattern. Our data suppose that chironomids do not have an obligate association with zebra mussels and possibly enter their mantle cavity inadvertently.

  20. Analysis of an ankyrin-like region in Epstein Barr Virus encoded (EBV BZLF-1 (ZEBRA protein: implications for interactions with NF-?B and p53

    Directory of Open Access Journals (Sweden)

    Ghoda Lucy Y

    2011-09-01

    Full Text Available Abstract Background The carboxyl terminal of Epstein-Barr virus (EBV ZEBRA protein (also termed BZLF-1 encoded replication protein Zta or ZEBRA binds to both NF-?B and p53. The authors have previously suggested that this interaction results from an ankyrin-like region of the ZEBRA protein since ankyrin proteins such as I?B interact with NF-?B and p53 proteins. These interactions may play a role in immunopathology and viral carcinogenesis in B lymphocytes as well as other cell types transiently infected by EBV such as T lymphocytes, macrophages and epithelial cells. Methods Randomization of the ZEBRA terminal amino acid sequence followed by statistical analysis suggest that the ZEBRA carboxyl terminus is most closely related to ankyrins of the invertebrate cactus I?B-like protein. This observation is consistent with an ancient origin of ZEBRA resulting from a recombination event between an ankyrin regulatory protein and a fos/jun DNA binding factor. In silico modeling of the partially solved ZEBRA carboxyl terminus structure using PyMOL software demonstrate that the carboxyl terminus region of ZEBRA can form a polymorphic structure termed ZANK (ZEBRA ANKyrin-like region similar to two adjacent I?B ankyrin domains. Conclusions Viral capture of an ankyrin-like domain provides a mechanism for ZEBRA binding to proteins in the NF-?B and p53 transcription factor families, and also provides support for a process termed "Ping-Pong Evolution" in which DNA viruses such as EBV are formed by exchange of information with the host genome. An amino acid polymorphism in the ZANK region is identified in ZEBRA from tumor cell lines including Akata that could alter binding of Akata ZEBRA to the p53 tumor suppressor and other ankyrin binding protein, and a novel model of antagonistic binding interactions between ZANK and the DNA binding regions of ZEBRA is suggested that may be explored in further biochemical and molecular biological models of viral replication.

  1. Current Status of Health and Safety Issues of Sodium/Metal Chloride (Zebra) Batteries

    International Nuclear Information System (INIS)

    This report addresses environmental, health, and safety (EH ampersand S) issues associated with sodium/ metal chloride batteries, in general, although most references to specific cell or battery types refer to units developed or being developed under the Zebra trademark. The report focuses on issues pertinent to sodium/metal chloride batteries and their constituent components; however, the fact that some ''issues'' arise from interaction between electric vehicle (EV) and battery design com- pels occasional discussion amid the context of EV vehicle design and operation. This approach has been chosen to provide a reasonably comprehensive account of the topic from a cell technology perspective and an applications perspective

  2. 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 indicate that zebra finches use a receptor that bases on radical pair processes for sensing the direction of the earth magnetic field in this short distance orientation behavior.

  3. Current Status of Health and Safety Issues of Sodium/Metal Chloride (Zebra) Batteries

    Energy Technology Data Exchange (ETDEWEB)

    Trickett, D.

    1998-12-15

    This report addresses environmental, health, and safety (EH&S) issues associated with sodium/ metal chloride batteries, in general, although most references to specific cell or battery types refer to units developed or being developed under the Zebra trademark. The report focuses on issues pertinent to sodium/metal chloride batteries and their constituent components; however, the fact that some ''issues'' arise from interaction between electric vehicle (EV) and battery design compels occasional discussion amid the context of EV vehicle design and operation. This approach has been chosen to provide a reasonably comprehensive account of the topic from a cell technology perspective and an applications perspective.

  4. Todralazine protects zebra fish from lethal doses of ionizing radiation: role of hematopoietic stem cell expansion

    International Nuclear Information System (INIS)

    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 5?M 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 its ability to increase the formation of erythrocytes in phenyl hydrazine induced anaemic zebra fish embryos. Todralazine is a HSC expanding agent with radioprotective potential and HSC expanding potential seems to be primarily responsible for that. Methodologies, results and its translational potential will be discussed in detail during presentation. (author)

  5. Assessment of Mercury Bioaccumulation in Zebra Cichlid (Cichlasoma Nigrofasciatum Exposed to Sublethal Concentrations of Permethrin

    Directory of Open Access Journals (Sweden)

    Mahdi Banaee

    2014-12-01

    Full Text Available Background: Aquatic ecosystems are frequently subjected to contamination by toxic heavy metals and pesticides, yet very little is known about the influence of pesticides on bioaccumulation of heavy metals in aquatic organisms. Mercury is a toxic metal with no known biological benefit to organisms. Bioavailability of mercury in aquatic environments depends on biological and non-biological parameters including other pollutants. Therefore, the objectives of this research were to determine the effects of permethrin on bioaccumulation of mercury in zebra cichlid. Methods: Acute toxicity (LC50 of permethrin and mercury chloride was evaluated by estimating mortality in Probit Model in SPSS (version 19.0 IBM. In sub-lethal toxicity, zebra cichlid (Cichlasoma nigrofasciatum was exposed to various concentrations of permethrin (0.0, 0.40, 0.80, 1.20 and 1.60 µg.L-1 combined with 20 µg.L-1 mercury chloride for 15 days. At the end of the experiment, mercury concentrations were measured using ICP-OES-Perkin elmer (optima 7300-DV. Results: 96 h LC50 values of permethrin and mercury for C. nigrofasciatum were calculated to be 17.55 µg.L-1 and 140.38 µg.L-1, respectively. Our results clearly showed that the bioaccumulation of mercury in the specimens increased with increasing concentrations of permethrin to 1.20 and 1.60 µg.L-1. Conclusion: Increasing the concentration of permethrin had synergistic effects on the bioaccumulation of mercury in fish.

  6. Parasitism can be a confounding factor in assessing the response of zebra mussels to water contamination

    International Nuclear Information System (INIS)

    Biological responses measured in aquatic organisms to monitor environmental pollution could be also affected by different biotic and abiotic factors. Among these environmental factors, parasitism has often been neglected even if infection by parasites is very frequent. In the present field investigation, the parasite infra-communities and zebra mussel biological responses were studied up- and downstream a waste water treatment plant in northeast France. In both sites, mussels were infected by ciliates and/or intracellular bacteria, but prevalence rates and infection intensities were different according to the habitat. Concerning the biological responses differences were observed related to the site quality and the infection status. Parasitism affects both systems but seemed to depend mainly on environmental conditions. The influence of parasites is not constant, but remains important to consider it as a potential confounding factor in ecotoxicological studies. This study also emphasizes the interesting use of integrative indexes to synthesize data set. Highlights: ? Study of potential bias associated with the use of infected zebra mussels in ecotoxicological studies. ? Presence of infected mussels on banks and channels, up- and downstream a waste water treatment plant. ? Parasitism influence on biological responses dependent of mussel population history. ? Integrative index, an interesting tool to synthesize the set of biological data. - Parasitism influence ocal data. - Parasitism influence on the host physiology would be strongly dependent on environmental conditions but remains a potential confounding factor in ecotoxicological studies.

  7. 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.

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

    International Nuclear Information System (INIS)

    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

  9. In Vivo Recording of Single-Unit Activity during Singing in Zebra Finches

    Science.gov (United States)

    Okubo, Tatsuo S.; Mackevicius, Emily L.; Fee, Michale S.

    2015-01-01

    The zebra finch is an important model for investigating the neural mechanisms that underlie vocal production and learning. Previous anatomical and gene expression studies have identified an interconnected set of brain areas in this organism that are important for singing. To advance our understanding of how these various brain areas act together to learn and produce a highly stereotyped song, it is necessary to record the activity of individual neurons during singing. Here, we present a protocol for recording single-unit activity in freely moving zebra finches during singing using a miniature, motorized microdrive. It includes procedures for both the microdrive implant surgery and the electrophysiological recordings. There are several advantages of this technique: (1) high-impedance electrodes can be used in the microdrive to obtain well-isolated single units; (2) a motorized microdrive is used to remotely control the electrode position, allowing neurons to be isolated without handling the bird, and (3) a lateral positioner is used to move electrodes into fresh tissue before each penetration, allowing recordings from well-isolated neurons over the course of several weeks. We also describe the application of the antidromic stimulation and the spike collision test to identify neurons based on the axonal projection patterns. PMID:25342072

  10. Cave crawling in zebra finch skulls : what is the functional interaural canal?

    DEFF Research Database (Denmark)

    Larsen, Ole Næsbye; Salomon, Rasmus

    Cave crawling in zebra finch skulls: what is the functional interaural canal? Ole Næsbye Larsen, Rasmus Salomon, Kenneth Kragh Jensen, and Jakob Christensen-Dalsgaard Department of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark The middle ears of birds are acoustically coupled through an air-filled interaural canal (IAC) often illustrated and modelled as a simple tube, which allows sound to propagate through the skull from one ear to the other and considerably enhance the cues for directional hearing. Theoretically, different combinations of frequency dependent gains and delays in the IAC can produce very different directionalities of the ears but it is still uncertain how interaural transmission gain and delay can be shaped by evolution by anatomical adaptations. A closer inspection of the zebra finch cranium using micro-CT scanning reveals that not only is IAC trabeculated and irregularly shaped but it also communicates with a set of highly complex, air-filled canals in the skull extending to the base of the beak. We tested the possible influence of these communicating cavities by measuring eardrum directionality and interaural transmission before and after filling the frontal cavities but found no dramatic effects. The question still remains what function these cavities serve and whether the ICA should be modelled as a simple tube.

  11. In vivo recording of single-unit activity during singing in zebra finches.

    Science.gov (United States)

    Okubo, Tatsuo S; Mackevicius, Emily L; Fee, Michale S

    2014-12-01

    The zebra finch is an important model for investigating the neural mechanisms that underlie vocal production and learning. Previous anatomical and gene expression studies have identified an interconnected set of brain areas in this organism that are important for singing. To advance our understanding of how these various brain areas act together to learn and produce a highly stereotyped song, it is necessary to record the activity of individual neurons during singing. Here, we present a protocol for recording single-unit activity in freely moving zebra finches during singing using a miniature, motorized microdrive. It includes procedures for both the microdrive implant surgery and the electrophysiological recordings. There are several advantages of this technique: (1) high-impedance electrodes can be used in the microdrive to obtain well-isolated single units; (2) a motorized microdrive is used to remotely control the electrode position, allowing neurons to be isolated without handling the bird, and (3) a lateral positioner is used to move electrodes into fresh tissue before each penetration, allowing recordings from well-isolated neurons over the course of several weeks. We also describe the application of the antidromic stimulation and the spike collision test to identify neurons based on the axonal projection patterns. PMID:25342072

  12. Sex differences of excitatory synaptic transmission in RA projection neurons of adult zebra finches.

    Science.gov (United States)

    Wang, Songhua; Meng, Wei; Liu, Shaoyi; Liao, Congshu; Huang, Qingyao; Li, Dongfeng

    2014-10-17

    Zebra finches are ideal animals to investigate sex difference in songbirds. Only males can sing. The brain nuclei controlling song learning and production in males are considerably larger than in females. The robust nucleus of the arcopallium (RA) is a premotor nucleus, playing a key role in controlling singing. RA receives denser synapse inputs in males than in females. Sex differences of excitatory synaptic transmission in the RA projection neurons (PNs) have not been reported. In the present study, using whole-cell voltage-clamp recording, spontaneous EPSCs (sEPSCs) and miniature EPSCs (mEPSCs) of RA PNs in the intact males and females were recorded. The average frequency and amplitude of sEPSCs/mEPSCs in the intact males were higher than females. The half-width and decay time of sEPSCs/mEPSCs in the intact males were longer than females. In order to verify whether these sex differences related to sex steroids, males were castrated. The average frequency of sEPSCs/mEPSCs in castrated males was lower than intact males and was similar to in females; the amplitude was not changed after castrating. These results demonstrate the sexually dimorphic of the excitatory synaptic transmission in the RA PNs, the RA PNs in males receive more excitatory synaptic transmission and these sex differences were partly affected by sex hormones. These findings contribute to further illuminate the neural mechanisms under the sexually dimorphism in song production of adult zebra finches. PMID:25220700

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

    International Nuclear Information System (INIS)

    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,s; 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

  14. The effects of delayed auditory feedback revealed by bone conduction microphone in adult zebra finches.

    Science.gov (United States)

    Fukushima, Makoto; Margoliash, Daniel

    2015-01-01

    Vocal control and learning are critically dependent on auditory feedback in songbirds and humans. Continuous delayed auditory feedback (cDAF) robustly disrupts speech fluency in normal humans and has ameliorative effects in some stutterers; however, evaluations of the effects of cDAF on songbirds are rare. We exposed singing young (141-151 days old) adult zebra finch males to high-amplitude cDAF. cDAF exposure was achieved by the recording of bone-conducted sounds using a piezoelectric accelerometer, which resulted in high-quality song recordings that were relatively uncontaminated by airborne sounds. Under this condition of cDAF, birds rapidly (2-6 days) changed their song syllable timing. The one bird for which we were able to maintain the accelerometer recordings over a long period of time recovered slowly over more than a month after cDAF was discontinued. These results demonstrate that cDAF can cause substantial changes in the motor program for syllable timing generation over short intervals of time in adult zebra finches. PMID:25739659

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

    Science.gov (United States)

    Chen, Jiani; Ten Cate, Carel

    2014-09-11

    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. PMID:25217867

  16. The zebra finch, Taeniopygia guttata: an avian model for investigating the neurobiological basis of vocal learning.

    Science.gov (United States)

    Mello, Claudio V

    2014-12-01

    Songbirds are capable of learning their vocalizations by copying a singing adult. This vocal learning ability requires juveniles to hear and memorize the sound of the adult song, and later to imitate it through a process involving sensorimotor integration. Vocal learning is a trait that songbirds share with humans, where it forms the basis of spoken language acquisition, with other avian groups (parrots and hummingbirds), and with a few other mammals (cetaceans, bats). It is however absent in traditional model organisms such as rodents and nonhuman primates. Zebra finches, a songbird species from Australia, are popular pets and are easy to breed. They also sing a relatively simple and stereotyped song that is amenable to quantitative analysis. Zebra finches have thus emerged as a choice model organism for investigating the neurobiological basis of vocal learning. A number of tools and methodologies have been developed to characterize the bioacoustics properties of their song, analyze the degree of accurate copying during vocal learning, map the brain circuits that control singing and song learning, and investigate the physiology of these circuits. Such studies have led to a large base of knowledge on song production and learning, and their underlying neural substrate. Several molecular resources have recently become available, including brain cDNA/EST databases, microarrays, BAC libraries, a molecular brain atlas, a complete genome assembly, and the ability to perform transgenesis. The recent availability of many other avian genomes provides unique opportunities for comparative analysis in the search for features unique to vocal learning organisms. PMID:25342070

  17. Acute inhibition of a cortical motor area impairs vocal control in singing zebra finches.

    Science.gov (United States)

    Yazaki-Sugiyama, Yoko; Yanagihara, Shin; Fuller, Patrick M; Lazarus, Michael

    2015-01-01

    Genetically targeted approaches that permit acute and reversible manipulation of neuronal circuit activity have enabled an unprecedented understanding of how discrete neuronal circuits control animal behavior. Zebra finch singing behavior has emerged as an excellent model for studying neuronal circuit mechanisms underlying the generation and learning of behavioral motor sequences. We employed a newly developed, reversible, neuronal silencing system in zebra finches to test the hypothesis that ensembles of neurons in the robust nucleus of the arcopallium (RA) control the acoustic structure of specific song parts, but not the timing nor the order of song elements. Subunits of an ivermectin-gated chloride channel were expressed in a subset of RA neurons, and ligand administration consistently suppressed neuronal excitability. Suppression of activity in a group of RA neurons caused the birds to sing songs with degraded elements, although the order of song elements was unaffected. Furthermore some syllables disappeared in the middle or at the end of song motifs. Thus, our data suggest that generation of specific song parts is controlled by a subset of RA neurons, whereas elements order coordination and timing of whole songs are controlled by a higher premotor area. PMID:25354166

  18. Discrimination of dynamic moving ripples in the zebra finch, Taeniopygia guttata

    Science.gov (United States)

    Osmanski, Michael S.; Dooling, Robert J.; Depireux, Didier A.

    2002-05-01

    Auditory processing of complex broadband sounds known as moving ripples has been studied both physiologically at the cortical level in mammals and psychophysically in humans [Depireux et al. (2001); Chi et al. (1999)]. These stimuli share spectro-temporal properties with many natural sounds, including species-specific vocalizations and the formant transitions of human speech [Versnel and Shamma (1998)]. One test of the generality of ripple processing beyond mammals would be to examine a non-mammalian species. Zebra finches may be excellent subjects for such a study because they produce complex broadband harmonic songs and neuronal responses in their auditory forebrain may be exquisitely tuned to the specific spectro-temporal patterns of their songs [Theunnissen and Doupe (1998)]. We trained these birds to discriminate between flat-spectrum broadband noise and moving ripples of different densities that move up or down in frequency at various rates. Results show that discrimination in zebra finches is better at those ripple densities and velocities which are prominent in their species-specific harmonic vocalizations. [Work supported by NIH Grant No. DC-00198 to RJD and NIDCD Training Grant No. DC-00046.

  19. Lipid imaging in the zebra finch brain with secondary ion mass spectrometry

    Science.gov (United States)

    Amaya, Kensey R.; Monroe, Eric B.; Sweedler, Jonathan V.; Clayton, David F.

    2007-02-01

    Lipids have diverse functions in the nervous system, but the study of their anatomical distributions in the intact brain is rather difficult using conventional methodologies. Here we demonstrate the application of high resolution time-of-flight (ToF) secondary ion mass spectrometry (SIMS) to image various lipid components and cholesterol across an entire brain section prepared from an adult zebra finch (Taeniopygia guttata), with a spatial resolution of 2.3 [mu]m, resulting in the formation of 11.5 megapixel chemical images. The zebra finch is a songbird in which specific neural and developmental functions have been ascribed to discrete "song control nuclei" of the forebrain. We have observed a relative increase of palmitic acid C16:0 and oleic acid C18:1 in song control nuclei versus the surrounding tissue, while phosphate (PO3-), representative of phospholipids, was lower in these regions. Cholesterol was present at a high level only in the white matter of the optic tectum. More diffuse distributions were observed for stearic, arachidonic, linolenic, and palmitoleic acids. The presented results illustrate that SIMS imaging is a useful approach for assessing changes in lipid content during song circuit development and song learning.

  20. Sexual differentiation of the zebra finch song system: potential roles for sex chromosome genes

    Directory of Open Access Journals (Sweden)

    Clayton David F

    2009-03-01

    Full Text Available Abstract Background Recent evidence suggests that some sex differences in brain and behavior might result from direct genetic effects, and not solely the result of the organizational effects of steroid hormones. The present study examined the potential role for sex-biased gene expression during development of sexually dimorphic singing behavior and associated song nuclei in juvenile zebra finches. Results A microarray screen revealed more than 2400 putative genes (with a false discovery rate less than 0.05 exhibiting sex differences in the telencephalon of developing zebra finches. Increased expression in males was confirmed in 12 of 20 by qPCR using cDNA from the whole telencephalon; all of these appeared to be located on the Z sex chromosome. Six of the genes also showed increased expression in one or more of the song control nuclei of males at post-hatching day 25. Although the function of half of the genes is presently unknown, we have identified three as: 17-beta-hydroxysteroid dehydrogenase type IV, methylcrotonyl-CoA carboxylase, and sorting nexin 2. Conclusion The data suggest potential influences of these genes in song learning and/or masculinization of song system morphology, both of which are occurring at this developmental stage.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1988-08-08

    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.

  2. Statistics and classification of the microwave zebra patterns associated with solar flares

    International Nuclear Information System (INIS)

    The microwave zebra pattern (ZP) is the most interesting, intriguing, and complex spectral structure frequently observed in solar flares. A comprehensive statistical study will certainly help us to understand the formation mechanism, which is not exactly clear now. This work presents a comprehensive statistical analysis of a big sample with 202 ZP events collected from observations at the Chinese Solar Broadband Radio Spectrometer at Huairou and the Ond?ejov Radiospectrograph in the Czech Republic at frequencies of 1.00-7.60 GHz from 2000 to 2013. After investigating the parameter properties of ZPs, such as the occurrence in flare phase, frequency range, polarization degree, duration, etc., we find that the variation of zebra stripe frequency separation with respect to frequency is the best indicator for a physical classification of ZPs. Microwave ZPs can be classified into three types: equidistant ZPs, variable-distant ZPs, and growing-distant ZPs, possibly corresponding to mechanisms of the Bernstein wave model, whistler wave model, and double plasma resonance model, respectively. This statistical classification may help us to clarify the controversies between the existing various theoretical models and understand the physical processes in the source regions.

  3. Overexpression a novel zebra fish spermatogenesis-associated gene 17 (SPATA17) induces apoptosis in GC-1 cells.

    Science.gov (United States)

    Nie, Dongsong; Liu, Y; Xiang, Y

    2011-08-01

    The spermatogenesis-associated 17 gene (SPATA17, previously named MSRG-11) was reported to be a candidate spermatocyte apoptosis-related gene which may play a critical role in human spermatogenesis, especially in meiosis. Analysis of SPATA17 expression and regulation in zebra fish may provide insight into the understanding of the complicated process of gonadogenesis and its potential function in spermatocyte cell apoptosis. In this study, we cloned and characterized the SPATA17 gene from zebra fish which consists of nine exons separated by eight introns. The consensus open reading frame (1258 bp) encodes a polypeptide of 357 amino acids which shares 44% identity with the human SPATA17 gene. Bioinformatic analysis reveals that SPATA17 protein contains three short calmodulin-binding motifs (IQ motif) and is considered to play a critical role in interactions with CaM proteins. Multi-tissue RT-PCR and Northern blot results demonstrated that the zebra fish SPATA17 gene was expressed strongly in testis and a slight amount of expression in ovary. Flow cytometry analysis and genomic DNA ladders result showed that the expression of SPATA17 protein in the GC-1 cell line could accelerate cell apoptosis. Analysis of the SPATA17 sequence and its spatial expression pattern indicate that this gene is highly conserved and may play an important role in the process of zebra fish gonadogenesis. PMID:21108043

  4. Zebra tape identification for the instantaneous angular speed computation and angular resampling of motorbike valve train measurements

    Science.gov (United States)

    Rivola, Alessandro; Troncossi, Marco

    2014-02-01

    An experimental test campaign was performed on the valve train of a racing motorbike engine in order to get insight into the dynamic of the system. In particular the valve motion was acquired in cold test conditions by means of a laser vibrometer able to acquire displacement and velocity signals. The valve time-dependent measurements needed to be referred to the camshaft angular position in order to analyse the data in the angular domain, as usually done for rotating machines. To this purpose the camshaft was fitted with a zebra tape whose dark and light stripes were tracked by means of an optical probe. Unfortunately, both manufacturing and mounting imperfections of the employed zebra tape, resulting in stripes with slightly different widths, precluded the possibility to directly obtain the correct relationship between camshaft angular position and time. In order to overcome this problem, the identification of the zebra tape was performed by means of the original and practical procedure that is the focus of the present paper. The method consists of three main steps: namely, an ad-hoc test corresponding to special operating conditions, the computation of the instantaneous angular speed, and the final association of the stripes with the corresponding shaft angular position. The results reported in the paper demonstrate the suitability of the simple procedure for the zebra tape identification performed with the final purpose to implement a computed order tracking technique for the data analysis.

  5. 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...

  6. Structure and expression of TLR4 in zebra finch (Taeniopygia guttata), the first Toll-like receptor in passerine birds.

    Czech Academy of Sciences Publication Activity Database

    Vinkler, Michal; Bryjová, Anna; Albrecht, Tomáš; Bryja, Josef

    Barcelona : AOPC, 2008. P-240. [Annual Meeting of the Society for Molecular Biology and Evolution. 05.06.2008-08.06.2008, Barcelona] Institutional research plan: CEZ:AV0Z60930519 Keywords : zebra finch * toll-like receptors Subject RIV: EB - Genetics ; Molecular Biology http://www.aopc.es/abst/obtimpres.php?idAbst=991

  7. 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 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.

  8. 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.

  9. The Origin of a “Zebra” Chromosome in Wheat Suggests Nonhomologous Recombination as a Novel Mechanism for New Chromosome Evolution and Step Changes in Chromosome Number

    OpenAIRE

    Zhang, Peng; Li, Wanlong; Friebe, Bernd; Gill, Bikram S

    2008-01-01

    An alloplasmic wheat line, TA5536, with the “zebra” chromosome z5A was isolated from an Elymus trachycaulus/Triticum aestivum backcross derivative. This chromosome was named “zebra” because of its striped genomic in situ hybridization pattern. Its origin was traced to nonhomologous chromosome 5A of wheat and 1Ht of Elymus; four chromatin segments were derived from chromosome 1Ht and five chromatin segments including the centromere from 5A. In this study, our objective was to determine the mec...

  10. Temporal variation in zebra mussel (Dreissena polymorpha) density structure the benthic food web and community composition on hard substrates in Lake Constance, Germany

    OpenAIRE

    Gergs, Rene?; Grey, Jonathan; Rothhaupt, Karl-otto

    2011-01-01

    Invasive species often influence existing biocenoses by altering their environment or facilitating the ecology of other species. Here we combined stable isotope analysis with quantitative benthic community sampling to investigate temporal variation in the influence of biodeposition of organic material (biodeposits) by the zebra mussel (Dreissena polymorpha) on the benthic food web in hard substrate habitats of Lake Constance, Germany. The accumulation of organic material excreted by zebra mus...

  11. Quagga and zebra mussel risk via veliger transfer by overland hauled boats

    Directory of Open Access Journals (Sweden)

    Larry B. Dalton

    2013-04-01

    Full Text Available Invasive quagga and zebra mussels (Dreissena rostriformis bugensis and Dreissena polymorpha, respectively pose a great threat to USwaters. Recreational boats constitute a significant risk for spreading the organisms. Recreational boats circulate large amounts of raw waterwhen in use, and if not drained and dried correctly can transport many mussel larvae, called veligers. Veligers experience very high mortality rates; however, the number of potentially transported veligers can be a serious risk to non-infested bodies of water, especially if multiple boats are involved. The risk of veliger transport was calculated for Lake Mead and Lake Michigan using boat capacities for water circulation and specific veliger density data. Results illustrate the importance of draining, drying, and/or decontaminating recreational boats after use.

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

    Science.gov (United States)

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

    2015-02-01

    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 micronutrients during sexual maturation showed reduced telomere loss; there was no such effect in males. These results suggest that micronutrients may influence rates of cellular senescence, but differences in micronutrient requirement and allocation strategies, probably linked to the development of sexual coloration, may underlie sex differences in response. PMID:25716087

  13. Chronic dietary toxicity of methylmercury in the zebra finch, Poephila guttata

    Energy Technology Data Exchange (ETDEWEB)

    Scheuhammer, A.M.

    1988-01-01

    Mercury (Hg) contamination of the environment through anthropogenic activity continues to be significant, and has resulted in the accumulation of elevated levels of Hg in invertebrates, fish and wildlife in certain Hg contaminated habitats. In addition, the availability of methylmercury (MeHg), a highly toxic and readily absorbable form of Hg, to the food chain is enhanced at low pH, an this has resulted in higher concentrations of Hg in various biota which inhabit environments sensitive to acid precipitation. The chronic dietary toxicity of MeHg has been investigated in a number of bird species including mallard ducks (Anas platyrhynchos, black ducks, pheasants, quail, and chickens. Except for a subchronic feeding study, the effects of MeHg on small passerines have not been studied. The present report describes the tissue accumulation and toxicity of MeHg in zebra finches (Poephila guttata) in response to chronic dietary exposure.

  14. A neural circuit mechanism for regulating vocal variability during song learning in zebra finches.

    Science.gov (United States)

    Garst-Orozco, Jonathan; Babadi, Baktash; Ölveczky, Bence P

    2014-01-01

    Motor skill learning is characterized by improved performance and reduced motor variability. The neural mechanisms that couple skill level and variability, however, are not known. The zebra finch, a songbird, presents a unique opportunity to address this question because production of learned song and induction of vocal variability are instantiated in distinct circuits that converge on a motor cortex analogue controlling vocal output. To probe the interplay between learning and variability, we made intracellular recordings from neurons in this area, characterizing how their inputs from the functionally distinct pathways change throughout song development. We found that inputs that drive stereotyped song-patterns are strengthened and pruned, while inputs that induce variability remain unchanged. A simple network model showed that strengthening and pruning of action-specific connections reduces the sensitivity of motor control circuits to variable input and neural 'noise'. This identifies a simple and general mechanism for learning-related regulation of motor variability. PMID:25497835

  15. In vivo detection of fluctuating brain steroid levels in zebra finches.

    Science.gov (United States)

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

    2014-12-01

    This protocol describes a method for the in vivo measurement of steroid hormones in brain circuits of the zebra finch. A guide cannula is surgically implanted into the skull, microdilysate is collected through a microdialysis probe that is inserted into the cannula, and steroid concentrations in the microdialysate are determined using the enzyme-linked immunosorbent assay (ELISA). In some cases, the steroids measured are derived locally (e.g., neural 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). A reverse-microdialysis ("retrodialysis") method that can be used to deliver pharmacological agents into the brain to influence local steroid neurochemistry as well as behavior is also discussed. PMID:25342066

  16. QUASI-PERIODIC WIGGLES OF MICROWAVE ZEBRA STRUCTURES IN A SOLAR FLARE

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Sijie; Tan, Baolin; Yan, Yihua [Key Laboratory of Solar Activity, National Astronomical Observatories Chinese Academy of Sciences, Beijing 100012 (China); Nakariakov, V. M.; Selzer, L. A., E-mail: sjyu@nao.cas.cn [Centre for Fusion, Space and Astrophysics, Physics Department, University of Warwick, Coventry CV4 7AL (United Kingdom)

    2013-11-10

    Quasi-periodic wiggles of microwave zebra pattern (ZP) structures with periods ranging from about 0.5 s to 1.5 s are found in an X-class solar flare on 2006 December 13 at the 2.6-3.8 GHz with the Chinese Solar Broadband Radio Spectrometer (SBRS/Huairou). Periodogram and correlation analysis show that the wiggles have two to three significant periodicities and are almost in phase between stripes at different frequencies. The Alfvén speed estimated from the ZP structures is about 700 km s{sup –1}. We find the spatial size of the wave-guiding plasma structure to be about 1 Mm with a detected period of about 1 s. This suggests that the ZP wiggles can be associated with the fast magnetoacoustic oscillations in the flaring active region. The lack of a significant phase shift between wiggles of different stripes suggests that the ZP wiggles are caused by a standing sausage oscillation.

  17. A light- and electron microscopic study of primordial germ cells in the zebra fish (Danio rerio)

    Scientific Electronic Library Online (English)

    Nazan, Deniz Koç; Rikap, Yüce.

    Full Text Available In sexually reproducing organisms, primordial germ cells (PGCs) give rise to the cells of the germ line, the gametes. In many animals, PGCs are set apart from somatic cells early during embryogenesis. This study explores the origin of primordial germ cells (PGCs) of the zebra fish and examines their [...] morphology during early development (1st day-15th day). PGCs were selectively stained by the alkaline phosphatase histochemical reaction and viewed by light and electron microscopy from the time they are first detectable in the yolk sac endoderm. PGCs occurred in the subendodermal space on the syncytial periblast; differing from the surrounding endodermal cells. Later the PGCs moved to between the blastoderm and yolk sac and transferred to the dorsal mesentery where they formed gonadal anlage with mesoderm cells. PGCs were easily distinguished from somatic cells by their morphology and low electron density of their nuclei. Under light microscopy, PCGs were rounded with a distinct cytoplasmic membrane.

  18. New records of 43 spider species from the Mountain Zebra National Park, South Africa (Arachnida: Araneae

    Directory of Open Access Journals (Sweden)

    A.S. Dippenaar-Schoeman

    2006-12-01

    Full Text Available This study forms part of the South African National Survey of Arachnida (SANSA, initiated in 1997 with the main aim to create an inventory of the arachnid fauna of South Africa (Dippenaar-Schoeman & Craemer 2000. One of the objectives of SANSA is to assess the number of arachnid species presently protected in conserved areas in the country. Check lists of spiders are now available for three national parks, three nature reserves and a conservancy. These areas include: Mountain Zebra National Park (Dippenaar-Schoeman 1988; Karoo National Park (Dippenaar-Schoeman et al. 1999; Kruger National Park (Dippenaar- Schoeman & Leroy 2002; Roodeplaatdam Nature Reserve (Dippenaar-Schoeman et al. 1989; Makelali Nature Reserve (Whitmore et al. 2001, 2002; Swartberg Nature Reserve (Dippenaar-Schoeman et al. 2005; and the Soutpansberg Conservancy (Foord et al. 2002.

  19. A Very Small and Super Strong Zebra Pattern Burst at the Beginning of a Solar Flare

    CERN Document Server

    Tan, Baolin; Zhang, Yin; Huang, Jing; Meszarosova, Hana; Karlicky, Marian; Yan, Yihua

    2014-01-01

    Microwave emission with spectral zebra pattern structures (ZPs) is observed frequently in solar flares and the Crab pulsar. The previous observations show that ZP is only a structure overlapped on the underlying broadband continuum with slight increments and decrements. This work reports an extremely unusual strong ZP burst occurring just at the beginning of a solar flare observed simultaneously by two radio telescopes located in China and Czech Republic and by the extreme ultraviolet (EUV) telescope on board NASA's satellite Solar Dynamics Observatory on 2013 April 11. It is a very short and super strong explosion whose intensity exceeds several times that of the underlying flaring broadband continuum emission, lasting for just 18 s. EUV images show that the flare starts from several small flare bursting points (FBPs). There is a sudden EUV flash with extra enhancement in one of these FBPs during the ZP burst. Analysis indicates that the ZP burst accompanying EUV flash is an unusual explosion revealing a str...

  20. Productivity of Mountain Reedbugk Redunca Fulvorufula (Afzelius, 1815 at the Mountain Zebra National Park

    Directory of Open Access Journals (Sweden)

    J. D Skinner

    1980-01-01

    Full Text Available Eighty two adult mountain reedbuck Redunca fulvoru- fula were collected during four seasons, autumn, winter, spring and summer at the Mountain Zebra National Park mainly during 1975 and 1976. Body mass and carcass characteristics varied little with season, body mass varying from 24,0-35,5 kg for all buck shot and dressing percentage always exeeded 50. According to KFI animals were all in fair to good condition. Sixty four percent of all ewes were pregnant and 38,5 lactating. Females and males bred throughout the year but there was a peak in births during mid-summer. The species is highly productive, well adapted to the niche it occupies and lends itself to exploitation for meat production.

  1. 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.

  2. QUASI-PERIODIC WIGGLES OF MICROWAVE ZEBRA STRUCTURES IN A SOLAR FLARE

    International Nuclear Information System (INIS)

    Quasi-periodic wiggles of microwave zebra pattern (ZP) structures with periods ranging from about 0.5 s to 1.5 s are found in an X-class solar flare on 2006 December 13 at the 2.6-3.8 GHz with the Chinese Solar Broadband Radio Spectrometer (SBRS/Huairou). Periodogram and correlation analysis show that the wiggles have two to three significant periodicities and are almost in phase between stripes at different frequencies. The Alfvén speed estimated from the ZP structures is about 700 km s–1. We find the spatial size of the wave-guiding plasma structure to be about 1 Mm with a detected period of about 1 s. This suggests that the ZP wiggles can be associated with the fast magnetoacoustic oscillations in the flaring active region. The lack of a significant phase shift between wiggles of different stripes suggests that the ZP wiggles are caused by a standing sausage oscillation

  3. Anatomically discrete sex differences in neuroplasticity in zebra finches as reflected by perineuronal nets.

    Science.gov (United States)

    Cornez, Gilles; Ter Haar, Sita M; Cornil, Charlotte A; Balthazart, Jacques

    2015-01-01

    Large morphological sex differences in the vertebrate brain were initially identified in song control nuclei of oscines. Besides gross differences between volumes of nuclei in males and females, sex differences also concern the size and dendritic arborization of neurons and various neurochemical markers, such as the calcium-binding protein parvalbumin (PV). Perineuronal nets (PNN) of the extracellular matrix are aggregates of different compounds, mainly chondroitin sulfate proteoglycans, that surround subsets of neurons, often expressing PV. PNN develop in zebra finches song control nuclei around the end of the sensitive period for song learning and tutor deprivation, known to delay the end of the song learning sensitive period, decreases the numbers of PNN in HVC. We demonstrate here the existence in zebra finches of a major sex difference (males > females) affecting the number of PNN (especially those surrounding PV-positive cells) in HVC and to a smaller extent the robust nucleus of the arcopallium, RA, the two main nuclei controlling song production. These differences were not present in Area X and LMAN, the lateral magnocellular nucleus of the anterior nidopallium. A dense expression of material immunoreactive for chondroitin sulfate was also detected in several nuclei of the auditory and visual pathways. This material was often organized in perineuronal rings but quantification of these PNN did not reveal any sex difference with the exception that the percentage of PNN surrounding PV-ir cells in the dorsal lateral mesencephalic nucleus, MLd, was larger in females than in males, a sex difference in the opposite direction compared to what is seen in HVC and RA. These data confirm and extend previous studies demonstrating the sex difference affecting PNN in HVC-RA by showing that this sex difference is anatomically specific and does not concern visual or auditory pathways. PMID:25848776

  4. Breeding Experience, Alternative Reproductive Strategies and Reproductive Success in a Captive Colony of Zebra Finches (Taeniopygia guttata)

    OpenAIRE

    Baran, Nicole M.; Adkins-Regan, Elizabeth

    2014-01-01

    Birds exhibit a remarkable diversity of different reproductive strategies both between and within species. Species such as the zebra finch (Taeniopygia guttata) may evolve the flexible use of alternative reproductive strategies, as well as benefit from prior breeding experience, which allows them to adaptively respond to unpredictable environments. In birds, the flexible use of alternative reproductive strategies, such as extra-pair mating, has been reported to be associated with fast reprodu...

  5. Research regarding the influence of royal jelly on sex reversal in zebra fishes (Danio rerio)

    OpenAIRE

    Silvia P?truic?; Adrian Grozea; Gabi Dumitrescu; Ioan B?n??ean-Dunea; Liliana Ciochin?; Marioara Nicula; Adriana D?ianu; Szidonia Szucs; Liliana Boca

    2010-01-01

    In this study we observed the influence of royal jelly on sex reversal in zebra fishes (Daniorerio). Experiments were made in the laboratories of aquaculture from Faculty of Animal Science andBiotechnologies, Timi?oara in the period 01.03.2010 – 15.05.2010 on 225 individuals. The dinamics ofstandard body weight, the standard length and the maximum body high at all individuals from treeexperimental variants were evaluated. It was indentified the number of males and females by directexaminat...

  6. Quantifying song bout production during zebra finch sensory-motor learning suggests a sensitive period for vocal practice

    OpenAIRE

    Johnson, Frank; Soderstrom, Ken; Whitney, Osceola

    2002-01-01

    Using an event-triggered recording system, the quantity of daily song bout production was measured weekly in male zebra finches (Taeniopygia guttata) during sensory-motor learning and at one year of age. Our aim was to ask whether the development of a stereotyped vocal pattern involves a practice-driven component. If so, we hypothesized that juvenile males learning song should sing more often than adults reciting a vocal pattern they had already learned, and that greater levels of juvenile si...

  7. Relaxation of magnetic field relative to plasma density revealed from microwave zebra patterns associated with solar flares

    OpenAIRE

    Yu, Sijie; Yan, Yihua; Tan, Baolin

    2012-01-01

    It is generally considered that the emission of microwave zebra pattern (ZP) structures requires high density and high temperatures, which is similar to the situation of the flaring region where primary energy releases. Therefore, the parameters analysis of ZPs may reveal the physical conditions of the flaring source region. This work investigates the variations of 74 microwave ZP structures observed by Chinese Solar Broadband Radio Spectrometer (SBRS/Huairou) at 2.6-3.8 GHz...

  8. 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.

  9. 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-1? and TNF-? 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.

  10. Molecular Cloning and Functional Characterization of Mannose Receptor in Zebra Fish (Danio rerio) during Infection with Aeromonas sobria.

    Science.gov (United States)

    Zheng, Feifei; Asim, Muhammad; Lan, Jiangfeng; Zhao, Lijuan; Wei, Shun; Chen, Nan; Liu, Xiaoling; Zhou, Yang; Lin, Li

    2015-01-01

    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-1? and TNF-? 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. PMID:25988382

  11. Odour-based natal nest recognition in the zebra finch (Taeniopygia guttata), a colony-breeding songbird.

    Science.gov (United States)

    Caspers, Barbara A; Krause, E Tobias

    2011-04-23

    Passerine birds have an extensive repertoire of olfactory receptor genes. However, the circumstances in which passerine birds use olfactory signals are poorly understood. The aim of this study is to investigate whether olfactory cues play a role in natal nest recognition in fledged juvenile passerines. The natal nest provides fledglings with a safe place for sleeping and parental food provisioning. There is a particular demand in colony-breeding birds for fledglings to be able to identify their nests because many pairs breed close to each other. Olfactory orientation might thus be of special importance for the fledglings, because they do not have a visual representation of the nest site and its position in the colony when leaving the nest for the first time. We investigated the role of olfaction in nest recognition in zebra finches, which breed in dense colonies of up to 50 pairs. We performed odour preference tests, in which we offered zebra finch fledglings their own natal nest odour versus foreign nest odour. Zebra finch fledglings significantly preferred their own natal nest odour, indicating that fledglings of a colony breeding songbird may use olfactory cues for nest recognition. PMID:20880859

  12. Contaminant and genotoxicity profiles of sediments and zebra mussels as indicators of chemical contamination in Hamilton Harbour

    International Nuclear Information System (INIS)

    Samples of bottom sediments, suspended sediments and Zebra mussels were collected from Hamilton Harbour, an embayment of western Lake Ontario. In addition, sediment samples were collected from creeks which flow into the Harbour. These sediment samples were extracted with dichloromethane and the organic extract was cleaned up prior to analysis for PAH and thia-arenes by GC-MS. These extracts were also subjected to genotoxicity bioassays (Ames assays) in two strains of Salmonella typhimurium (a TA98-like strain, YG1024-S9 and a TA100-like strain, YG1025 + S9). The sediment and Zebra mussels samples collected near sites of heavy coal tar contamination showed PAH, thia-arene and genotoxicity profiles that are very similar to the corresponding profiles for coal tar. These observations are consistent with the resuspension and distribution of coal tar-contaminated bottom sediments in the water column. The sediment samples collected in a major creek entering the Harbor and the sediment and Zebra mussels samples collected in Windemere Arm near the mouth of this creek showed very different chemical and genotoxicity profiles. Thus, the chemical and genotoxicity burdens on Hamilton Harbour posed by the resuspension of coal tar-contaminated sediments and the inputs from urban activity into a major creek and the Harbor can be differentiated

  13. 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.

  14. Within-year differences in reproductive investment in laboratory zebra finches ( Taeniopygia guttata), an opportunistically breeding bird

    Science.gov (United States)

    Williamson, Kathryn; Gilbert, Lucy; Rutstein, Alison N.; Pariser, Emma C.; Graves, Jeff A.

    2008-12-01

    Reproduction in opportunistically breeding bird species has traditionally been considered non-seasonal with individuals taking advantage of favourable environmental conditions as they arise. However, some studies imply that this opportunistic breeding may be superimposed on an underlying seasonality, which has effects on the readiness to breed when conditions are favourable. The zebra finch ( Taeniopygia guttata) is the classic opportunistic breeder and widely used as such in studies. In a series of laboratory-based breeding experiments, we found evidence to suggest that there are seasonal differences in maternal reproductive investment in the zebra finch even when photoperiod, temperature, relative humidity and diet were held constant. Females showed highly significant seasonal differences in clutch size and egg mass with laying order. Clutch size showed a spring/summer peak typical of multi-brooded species in the wild. There was also a significant increase in egg mass with laying order in all seasons except winter. This variation in breeding parameters with season may allow females to adjust investment depending on the potential fitness returns from a given reproductive attempt. These findings also raise a warning about interpreting results of multiple zebra finch breeding experiments that have been carried out in different seasons.

  15. Ecological impact assessment of sediment remediation in a metal-contaminated lowland river using translocated zebra mussels and resident macroinvertebrates

    International Nuclear Information System (INIS)

    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. ? Bioammunity 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.

  16. 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.

  17. Producción secundaria e índice de condición en Arca zebra (Mollusca: Bivalvia) del Golfo de Cariaco, Venezuela

    Scientific Electronic Library Online (English)

    Antulio, Prieto Arcas; Omar, Ramos A.; Dwight, Arrieche; José, Villalba; César, Lodeiros.

    2001-06-01

    Full Text Available Se estudió la biomasa, producción secundaria e índice de condición del bivalvo Arca zebra, desde agosto, 1984 hasta agosto, 1985 en Pariche, localidad situada en la costa norte del Golfo de Cariaco, Venezuela. La densidad promedio fue de 37 ind.m-2, con una mayor abundancia a 3 m de profundidad (49. [...] 75 ind.m-2). La estructura poblacional es estable con reclutamientos en octubre, diciembre 1984 y junio 19885. Los valores bimensuales de biomasa oscilaron entre 189.86 g Ps m-2 (agosto-84) y 28.51 g Ps m-2 (octubre-84), con un promedio de 93.69 g Ps m-2, y no presentaron diferencias significativas (Fs, P 0.05). Utilizando un método para poblaciones con reproducción contínua y edades no separables, se obtuvo una producción secundaria de 131.61 g Ps. m-2.año-1, y la relación P/B de1.41 año-1. La mayor producción secundaria ocurrió entre febrero 1985 y agosto 1985 (65%), con el mayor aporte por el intervalo 60.00-79.95 mm (45.73%). Se observaron cambios significativos en la variación mensual del índice de condición (IC= (Ps/ Ph) x100) en dos clases de tallas analizadas, presentando los valores más altos en julio de 1985 (26.84%) y el mínimo en enero de 1985 (16.31%). Abstract in english Production and condition index of a turkeywing (Arca zebra) population were studied from August 1984 to August 1985 in Pariche, Cariaco Gulf, Venezuela. Production was studied through bimonthly collections using a method designed for populations with continuous reproduction and indistinguishable age [...] classes. The population distribution was stable with a mean density of 37 ind.m-2. A production of 131.61 g dry weight m-2.year-1 was calcuclated from data on density, biomass and weight increase along the year. Highest production was between February 1985 and August 1985 (65%) and concentrated in individuals 60.00-79.95 mm long (45.73%). There was large seasonal variation in the mean monthly condition index (IC= (Ps/Ph) x100) in the two size classes examined: it reached a maximum in July 1985 (26.84%) and a minimum in January 1985 (16.31%).

  18. Producción secundaria e índice de condición en Arca zebra (Mollusca: Bivalvia del Golfo de Cariaco, Venezuela

    Directory of Open Access Journals (Sweden)

    Antulio Prieto Arcas

    2001-06-01

    Full Text Available Se estudió la biomasa, producción secundaria e índice de condición del bivalvo Arca zebra, desde agosto, 1984 hasta agosto, 1985 en Pariche, localidad situada en la costa norte del Golfo de Cariaco, Venezuela. La densidad promedio fue de 37 ind.m-2, con una mayor abundancia a 3 m de profundidad (49.75 ind.m-2. La estructura poblacional es estable con reclutamientos en octubre, diciembre 1984 y junio 19885. Los valores bimensuales de biomasa oscilaron entre 189.86 g Ps m-2 (agosto-84 y 28.51 g Ps m-2 (octubre-84, con un promedio de 93.69 g Ps m-2, y no presentaron diferencias significativas (Fs, P 0.05. Utilizando un método para poblaciones con reproducción contínua y edades no separables, se obtuvo una producción secundaria de 131.61 g Ps. m-2.año-1, y la relación P/B de1.41 año-1. La mayor producción secundaria ocurrió entre febrero 1985 y agosto 1985 (65%, con el mayor aporte por el intervalo 60.00-79.95 mm (45.73%. Se observaron cambios significativos en la variación mensual del índice de condición (IC= (Ps/ Ph x100 en dos clases de tallas analizadas, presentando los valores más altos en julio de 1985 (26.84% y el mínimo en enero de 1985 (16.31%.Production and condition index of a turkeywing (Arca zebra population were studied from August 1984 to August 1985 in Pariche, Cariaco Gulf, Venezuela. Production was studied through bimonthly collections using a method designed for populations with continuous reproduction and indistinguishable age classes. The population distribution was stable with a mean density of 37 ind.m-2. A production of 131.61 g dry weight m-2.year-1 was calcuclated from data on density, biomass and weight increase along the year. Highest production was between February 1985 and August 1985 (65% and concentrated in individuals 60.00-79.95 mm long (45.73%. There was large seasonal variation in the mean monthly condition index (IC= (Ps/Ph x100 in the two size classes examined: it reached a maximum in July 1985 (26.84% and a minimum in January 1985 (16.31%.

  19. Analytical developments for the speciation of uranium in zebra fish (Danio rerio) gills after exposure

    International Nuclear Information System (INIS)

    The objective of this thesis is to study the cellular compartmentalization and the chelation of uranium (U) by cytosolic proteins of gill cells of the zebra fish (Danio rerio, model specie in aquatic toxicology) under different direct exposure conditions (chronic vs. acute, 20 and 250 ?g.L-1). This study required the development of hyphenated techniques (SEC, IEF off-gel, RP-UHPLC for the separation, ICP-SFMS, ESI-FTMS/MS for the detection) with the main challenges of maintaining the non-covalent U-biomolecule interactions and enhancing sensitivity for the analysis of environmentally relevant samples. After extraction, 24% to 32% of the total U detected in the gills were present in the cytosolic fraction, in which the U distribution on the biomolecules (as a function of their MW and pI) varied depending on the exposure level. Finally, U target biomolecules mapping allowed us (i) to highlight a particular affinity of U for acidic and/or P-containing proteins and (ii) to identify 24 protein candidates for U binding. (author)

  20. MICROWAVE ZEBRA PATTERN STRUCTURES IN THE X2.2 SOLAR FLARE ON 2011 FEBRUARY 15

    International Nuclear Information System (INIS)

    A zebra pattern (ZP) structure is the most intriguing fine structure on the dynamic spectrograph of a solar microwave burst. On 2011 February 15, an X2.2 flare event erupted on the solar disk, which is the first X-class flare since the solar Schwabe cycle 24. It is interesting that there are several microwave ZPs observed by the Chinese Solar Broadband Radio Spectrometer (SBRS/Huairou) at a frequency of 6.40-7.00 GHz (ZP1) and at a frequency of 2.60-2.75 GHz (ZP2) and by the Yunnan Solar Broadband Radio Spectrometer (SBRS/Yunnan) at a frequency of 1.04-1.13 GHz (ZP3). The most important phenomenon is the unusual high-frequency ZP structure (ZP1, up to 7.00 GHz) that occurred in the early rising phase of the flare and the two ZP structures (ZP2, ZP3) with relatively low frequencies that occurred in the decay phase of the flare. By scrutinizing the current prevalent theoretical models of ZP structure generations and comparing their estimated magnetic field strengths in the corresponding source regions, we suggest that the double plasma resonance model is the most probable one for explaining the formation of microwave ZPs, which may derive the magnetic field strengths at about 230-345 G, 126-147 G, and 23-26 G in the source regions of ZP1, ZP2, and ZP3, respectively.

  1. Research regarding the influence of royal jelly on sex reversal in zebra fishes (Danio rerio

    Directory of Open Access Journals (Sweden)

    Silvia P?truic?

    2010-11-01

    Full Text Available In this study we observed the influence of royal jelly on sex reversal in zebra fishes (Daniorerio. Experiments were made in the laboratories of aquaculture from Faculty of Animal Science andBiotechnologies, Timi?oara in the period 01.03.2010 – 15.05.2010 on 225 individuals. The dinamics ofstandard body weight, the standard length and the maximum body high at all individuals from treeexperimental variants were evaluated. It was indentified the number of males and females by directexamination of the body and microscopic observation of histological samples. In the first experimentalvariant the food was mixed with 0.02 g powdered royal jelly and recorded at the end of the experiment70.76% females and 29.24% males. In the second experimental variant, a double dose of powderedroyal jelly was mixed in the feed, this leading to the increasing of females in the group to 81,19%. Inthe control variant the percentage of females was 50.7% and the percentage of males was 49.3%.

  2. Cave crawling in zebra Finch skulls : Which anatomical structures constitute the functional intraaural Canal?

    DEFF Research Database (Denmark)

    Larsen, Ole Næsbye; Salomon, Rasmus

    The middle ears of birds are acoustically coupled through an air-filled interaural canal, often illustrated and modelled as a simple tube. It allows sound to propagate through the skull from one ear to the other and considerably enhance the cues for directional hearing by interaction with the external sound field driving the eardrum vibrations. Theoretically, different combinations of frequency dependent gains and delays of sound in the interaural canal can produce very different directionalities of the ears but it still remains uncertain how interaural transmission gain and delay can be shaped by anatomical adaptations during evolution. A closer inspection of the zebra finch cranium using micro-CT scanning reveals that not only is IAC trabeculated and irregularly shaped but it also communicates with a set of highly complex, air-filled canals in the skull extending to the base of the beak. We tested the possible influence of these communicating cavities by measuring eardrum directionality and interaural transmission before and after filling the frontal cavities with dyed fat but found no dramatic effects. We will discuss what function the cavities serve and whether the ICA should be represented by a simple tube in future models

  3. An optimized protocol for high-throughput in situ hybridization of zebra finch brain.

    Science.gov (United States)

    Carleton, Julia B; Lovell, Peter V; McHugh, Anne; Marzulla, Tessa; Horback, Katy L; Mello, Claudio V

    2014-12-01

    In situ hybridization (ISH) is a sensitive technique for documenting the tissue distribution of mRNAs. Advanced nonradioactive ISH methods that are based on the use of digoxigenin (DIG)-labeled probes and chromogenic detection have better spatial resolution than emulsion autoradiography techniques and, when paired with high-resolution digital imaging, allow for large-scale profiling of gene expression at cellular resolution within a histological context. However, technical challenges restrict the number of genes that can be investigated in a small laboratory setting. This protocol describes an optimized, low-cost, small-footprint, high-throughput ISH procedure to detect gene expression patterns in 10-µm brain sections from zebra finches. It uses DIG-labeled riboprobes synthesized from cDNA templates available through the Songbird Neurogenomics Consortium. The method is compatible with high-resolution digital imaging; it produces images with low background and a resolution approaching that of immunohistochemical methods. Approximately 180 slides can be processed each week using this protocol, but it can be scaled to accommodate a broad range of tissues from which cryosections can be obtained. PMID:25342071

  4. Increased activity correlates with reduced ability to mount immune defenses to endotoxin in zebra finches.

    Science.gov (United States)

    Lopes, Patricia C; Springthorpe, Dwight; Bentley, George E

    2014-10-01

    When suffering from infection, animals experience behavioral and physiological alterations that potentiate the immune system's ability to fight pathogens. The behavioral component of this response, termed "sickness behavior," is characterized by an overall reduction in physical activity. A growing number of reports demonstrate substantial flexibility in these sickness behaviors, which can be partially overcome in response to mates, intruders and parental duties. Since it is hypothesized that adopting sickness behaviors frees energetic resources for mounting an immune response, we tested whether diminished immune responses coincided with reduced sickness behaviors by housing male zebra finches (Taeniopygia guttata) in social conditions that alter their behavioral response to an endotoxin. To facilitate our data collection, we developed and built a miniaturized sensor capable of detecting changes in dorsoventral acceleration and categorizing them as different behaviors when attached to the finches. We found that the immune defenses (quantified as haptoglobin-like activity, ability to change body temperature and bacterial killing capacity) increased as a function of increased time spent resting. The findings indicate that when animals are sick attenuation of sickness behaviors may exact costs, such as reduced immune function. The extent of these costs depends on how relevant the affected components of immunity are for fighting a specific infection. PMID:24888267

  5. Pair bond formation is impaired by VPAC receptor antagonism in the socially monogamous zebra finch.

    Science.gov (United States)

    Kingsbury, Marcy A; Goodson, James L

    2014-10-01

    A variety of recent data demonstrate that vasoactive intestinal polypeptide (VIP) and VPAC receptors (which bind VIP, and to a lesser extent, pituitary adenylatecyclase activating peptide) are important for numerous social behaviors in songbirds, including grouping and aggression, although VIP relates to these behaviors in a site-specific manner. In order to determine the global effects of central VPAC receptor activation on social behavior, we here infused a VPAC receptor antagonist or vehicle twice daily into the lateral ventricle of colony-housed male and female zebra finches and quantified a wide range of behaviors. Aggressive behaviors were not altered by ventricular infusions, consistent with known opposing, site-specific relationships of VIP innervation to aggression. Courtship and self-maintenance behaviors were likewise not altered. However, VPAC antagonism produced significant deficits in pair bonding. Antagonist subjects took longer to form a pair bond and were paired for significantly fewer observation sessions relative to control subjects (median 1.5 of 6 observation sessions for antagonist subjects versus 4 for control subjects). Antagonist subjects were also significantly less likely to be paired in the final observation session. Based on the known distribution of VPAC receptors in finches and other vertebrates, we propose that VPAC receptors may mediate pair bonding via a variety of brain areas that are known to be important for the establishment of partner preferences in voles, including the lateral septum, ventral tegmental area, nucleus accumbens and ventral pallidum. PMID:25014003

  6. Behavior-linked FoxP2 regulation enables zebra finch vocal learning.

    Science.gov (United States)

    Heston, Jonathan B; White, Stephanie A

    2015-02-18

    Mutations in the FOXP2 transcription factor cause an inherited speech and language disorder, but how FoxP2 contributes to learning of these vocal communication signals remains unclear. FoxP2 is enriched in corticostriatal circuits of both human and songbird brains. Experimental knockdown of this enrichment in song control neurons of the zebra finch basal ganglia impairs tutor song imitation, indicating that adequate FoxP2 levels are necessary for normal vocal learning. In unmanipulated birds, vocal practice acutely downregulates FoxP2, leading to increased vocal variability and dynamic regulation of FoxP2 target genes. To determine whether this behavioral regulation is important for song learning, here, we used viral-driven overexpression of FoxP2 to counteract its downregulation. This manipulation disrupted the acute effects of song practice on vocal variability and caused inaccurate song imitation. Together, these findings indicate that dynamic behavior-linked regulation of FoxP2, rather than absolute levels, is critical for vocal learning. PMID:25698728

  7. EFFECTS OF ORGANOPHOSPHATES ON ACUTE POISONING AND ACETYL CHOLINESTERASE INHIBITION IN ZEBRA FISH

    Directory of Open Access Journals (Sweden)

    TH Sukirtha* MV Usharani

    2013-03-01

    Full Text Available Organophosphates (Ops. are the most widely used insecticides available today. These are a group of insecticides used in chemical sprays to kill bugs, and insects in orchards, vineyards, vegetables and cereal crops. The present study examined effects of the pesticide Methyl parathion, Dichlorvos and Chlorpyrifos on adult zebra fish were exposed to various concentrations (5, 10 & 25mg/L for 24 and 48hrs acute toxic study. Chlorpyrifos showed mortality in all concentrations and Methyl parathion and Dichlorvos showed the same in 25 mg/L. LC 50 value for Methyl parathion and Dichlorvos was 5 & 10 mg/L respectively. The total protein, LPO content was increased except SOD, Catalase in the brain tissue of the treated fishes.  There was no significant decrease in the GPX activity at 5ppm test groups. The GPX activity decreased significantly in test group treated with 10ppm and a significant difference was found between 5ppm and 10ppm test groups. The histopathological studies of brain tissue showed that neuronal degeneration and tissue damages in the brain of treated fishes when compared with the control. Ops. produce toxicity by inhibiting the cholinesterase enzymes in the nervous system. Monitoring of acetyl cholinesterase (AChE inhibition has been widely used in terrestrial and freshwater aquatic systems as an indicator of OP exposure and effects.

  8. Cell Degradation of a Na-NiCl2 (ZEBRA) Battery

    Energy Technology Data Exchange (ETDEWEB)

    Li, Guosheng; Lu, Xiaochuan; Kim, Jin Yong; Lemmon, John P.; Sprenkle, Vincent L.

    2013-11-01

    In this work, the parameters influencing the degradation of a Na-NiCl2 (ZEBRA) battery were investigated. Planar Na-NiCl2 cells using ?”-alumina solid electrolyte (BASE) were tested with different C-rates, Ni/NaCl ratios, and capacity windows, in order to identify the key parameters for the degradation of Na-NiCl2 battery. The morphology of NaCl and Ni particles were extensively investigated after 60 cycles under various test conditions using a scanning electron microscope. A strong correlation between the particle size (NaCl and Ni) and battery degradation was observed in this work. Even though the growth of both Ni and NaCl can influence the cell degradation, our results indicate that the growth of NaCl is a dominant factor in cell degradation. The use of excess Ni seems to play a role in tolerating the negative effects of particle growth on degradation since the available active surface area of Ni particles can be still sufficient even after particle growth. For NaCl, a large cycling window was the most significant factor, of which effects were amplified with decrease in Ni/NaCl ratio.

  9. MICROWAVE ZEBRA PATTERN STRUCTURES IN THE X2.2 SOLAR FLARE ON 2011 FEBRUARY 15

    Energy Technology Data Exchange (ETDEWEB)

    Tan Baolin; Yan Yihua; Tan Chengming; Sych, Robert [Key Laboratory of Solar Activity, National Astronomical Observatories Chinese Academy of Sciences, Beijing 100012 (China); Gao Guannan [National Astronomical Observatories/Yunnan Astronomical Observatories Chinese Academy of Sciences, Kunming 650011, Yunnan Province (China)

    2012-01-10

    A zebra pattern (ZP) structure is the most intriguing fine structure on the dynamic spectrograph of a solar microwave burst. On 2011 February 15, an X2.2 flare event erupted on the solar disk, which is the first X-class flare since the solar Schwabe cycle 24. It is interesting that there are several microwave ZPs observed by the Chinese Solar Broadband Radio Spectrometer (SBRS/Huairou) at a frequency of 6.40-7.00 GHz (ZP1) and at a frequency of 2.60-2.75 GHz (ZP2) and by the Yunnan Solar Broadband Radio Spectrometer (SBRS/Yunnan) at a frequency of 1.04-1.13 GHz (ZP3). The most important phenomenon is the unusual high-frequency ZP structure (ZP1, up to 7.00 GHz) that occurred in the early rising phase of the flare and the two ZP structures (ZP2, ZP3) with relatively low frequencies that occurred in the decay phase of the flare. By scrutinizing the current prevalent theoretical models of ZP structure generations and comparing their estimated magnetic field strengths in the corresponding source regions, we suggest that the double plasma resonance model is the most probable one for explaining the formation of microwave ZPs, which may derive the magnetic field strengths at about 230-345 G, 126-147 G, and 23-26 G in the source regions of ZP1, ZP2, and ZP3, respectively.

  10. The estimation of herbage yields under fire and grazing treatments in the Mountain Zebra National Park

    Directory of Open Access Journals (Sweden)

    J. De Klerk

    2001-07-01

    Full Text Available The application of fire as a management tool is often used to change the species composition of the vegetation and its cover to maintain plant communities in a specific successional stage. This study investigates the influence of two fire treatments (a head and a back fire on the plateau grassland communities in the Mountain Zebra National Park (MZNP. The production of herbage yield on grazed areas and areas protected from grazing which were subjected to two fire treatments, were compared with that of an unburnt control area subjected to grazing in the same homogenous grassland over two growing seasons. No differences were found in herbage production between the two fire treatment areas. After the burn the grazing exclosures achieved the same herbage yield as the control area within two growing seasons. In comparison, the grazed areas could after the burn only achieve a herbage yield equal to 55.7 of that of the control area. The results indicate that fire stimulates active vegetation growth on the plateau grasslands in MZNP leading to a higher production rate and better utilisation by game.

  11. Microwave Zebra Pattern Structures in the X2.2 Solar Flare on Feb 15, 2011

    CERN Document Server

    Tan, Baolin; Tan, Chengming; Sych, Robert; Gao, Guannan

    2011-01-01

    Zebra pattern structure (ZP) is the most intriguing fine structure on the dynamic spectrograph of solar microwave burst. On 15 February 2011, there erupts an X2.2 flare event on the solar disk, it is the first X-class flare since the solar Schwabe cycle 24. It is interesting that there are several microwave ZPs observed by the Chinese Solar Broadband Radiospectrometer (SBRS/Huairou) at frequency of 6.40 ~ 7.00 GHz (ZP1), 2.60 ~ 2.75 GHz (ZP2), and the Yunnan Solar Broadband Radio Spectrometer (SBRS/Yunnan) at frequency of 1.04 ~ 1.13 GHz (ZP3). The most important phenomena is the unusual high-frequency ZP structure (ZP1, up to 7.00 GHz) occurred in the early rising phase of the flare, and there are two ZP structure (ZP2, ZP3) with relative low frequencies occurred in the decay phase of the flare. By scrutinizing the current prevalent theoretical models of ZP structure generations, and comparing their estimated magnetic field strengths in the corresponding source regions, we suggest that the double plasma reso...

  12. Maternal effects due to male attractiveness affect offspring development in the zebra finch.

    Science.gov (United States)

    Gilbert, L; Williamson, K A; Hazon, N; Graves, J A

    2006-07-22

    Maternal effects occur when offspring phenotype is influenced by environmental factors experienced by the mother. Mothers are predicted to invest differentially in offspring in ways that will maximize offspring fitness depending on the environment she expects them to encounter. Here, we test for maternal effects in response to mate attractiveness on offspring developmental traits in the zebra finch Taeniopygia guttata. We controlled for parental genetic quality by manipulating male attractiveness using coloured leg rings and by randomly assigning mating pairs. The potential confounding effect of differential nestling care was controlled for by cross-fostering clutches and by allowing for variance due to foster father attractiveness in general linear models. We found a difference in egg mass investment between attractiveness groups and, importantly, we found that all of the offspring traits we measured varied with the attractiveness of the father. This provides strong evidence for maternal effects in response to mate attractiveness. Furthermore, due to the experiment design, we can conclude that these effects were mediated by differential investment of egg resources and not due to genetic differences or differences in nestling care. PMID:16790409

  13. Inner-shell radiation from wire array implosions on the Zebra generator

    Science.gov (United States)

    Ouart, N. D.; Giuliani, J. L.; Dasgupta, A.; Safronova, A. S.; Kantsyrev, V. L.; Esaulov, A. A.; Shrestha, I.; Weller, M. E.; Shlyaptseva, V.; Osborne, G. C.; Stafford, A.; Keim, S.; Apruzese, J. P.; Clark, R. W.

    2014-03-01

    Implosions of brass wire arrays on Zebra have produced L-shell radiation as well as inner-shell K? and K? transitions. The L-shell radiation comes from ionization stages around the Ne-like charge state that is largely populated by a thermal electron energy distribution function, while the K-shell photons are a result of high-energy electrons ionizing or exciting an inner-shell (1s) electron from ionization stages around Ne-like. The K- and L-shell radiations were captured using two time-gated and two axially resolved time-integrated spectrometers. The electron beam was measured using a Faraday cup. A multi-zone non-local thermodynamic equilibrium pinch model with radiation transport is used to model the x-ray emission from experiments for the purpose of obtaining plasma conditions. These plasma conditions are used to discuss some properties of the electron beam generated by runaway electrons. A simple model for runaway electrons is examined to produce the K? radiation, but it is found to be insufficient.

  14. Inner-shell radiation from wire array implosions on the Zebra generator

    Energy Technology Data Exchange (ETDEWEB)

    Ouart, N. D.; Giuliani, J. L.; Dasgupta, A. [Plasma Physics Division, Naval Research Laboratory, Washington, District of Columbia 20375 (United States); Safronova, A. S.; Kantsyrev, V. L.; Esaulov, A. A.; Shrestha, I.; Weller, M. E.; Shlyaptseva, V.; Osborne, G. C.; Stafford, A.; Keim, S. [Physics Department, University of Nevada, Reno, Nevada 89557 (United States); Apruzese, J. P. [Consultant to NRL through Engility Corp., Chantilly, Virginia 20151 (United States); Clark, R. W. [Berkeley Research Associates, Beltsville, Maryland 20705 (United States)

    2014-03-15

    Implosions of brass wire arrays on Zebra have produced L-shell radiation as well as inner-shell K? and K? transitions. The L-shell radiation comes from ionization stages around the Ne-like charge state that is largely populated by a thermal electron energy distribution function, while the K-shell photons are a result of high-energy electrons ionizing or exciting an inner-shell (1s) electron from ionization stages around Ne-like. The K- and L-shell radiations were captured using two time-gated and two axially resolved time-integrated spectrometers. The electron beam was measured using a Faraday cup. A multi-zone non-local thermodynamic equilibrium pinch model with radiation transport is used to model the x-ray emission from experiments for the purpose of obtaining plasma conditions. These plasma conditions are used to discuss some properties of the electron beam generated by runaway electrons. A simple model for runaway electrons is examined to produce the K? radiation, but it is found to be insufficient.

  15. Multi-functional foot use during running in the zebra-tailed lizard (Callisaurus draconoides)

    CERN Document Server

    Li, Chen; Goldman, Daniel I; 10.1242/jeb.061937

    2013-01-01

    A diversity of animals that run on solid, level, flat, non-slip surfaces appear to bounce on their legs; elastic elements in the limbs can store and return energy during each step. The mechanics and energetics of running in natural terrain, particularly on surfaces that can yield and flow under stress, is less understood. The zebra-tailed lizard (Callisaurus draconoides), a small desert generalist with a large, elongate, tendinous hind foot, runs rapidly across a variety of natural substrates. We use high speed video to obtain detailed three-dimensional running kinematics on solid and granular surfaces to reveal how leg, foot, and substrate mechanics contribute to its high locomotor performance. Running at ~10 body length/s (~1 m/s), the center of mass oscillates like a spring-mass system on both substrates, with only 15% reduction in stride length on the granular surface. On the solid surface, a strut-spring model of the hind limb reveals that the hind foot saves about 40% of the mechanical work needed per s...

  16. EVALUATION OF BIOTIC AND TREATMENT FACTORS RELATING TO BACTERIAL CONTROL OF ZEBRA MUSSELS

    International Nuclear Information System (INIS)

    Testing over the last quarter has indicated the following regarding control of zebra mussels with bacterium Pseudomonas fluorescens strain CL0145A: (1) the concentration of bacteria suspended in water is directly correlated with mussel kill; (2) the ratio of bacterial mass per mussel, if too low, could limit mussel kill; a treatment must be done at a high enough ratio so that mussels do not deplete all the suspended bacteria before the end of the desired exposure period; (3) bacteria appear to lose almost all their toxicity after suspension for 24 hr in highly oxygenated water; (4) in a recirculating pipe system, the same percentage mussel kill will be achieved irrespective of whether all the bacteria are applied at once or divided up and applied intermittently in smaller quantities over a 10-hr period. Since this is the fourth quarterly report, a summation of all test results over the last twelve months is provided as a table in this report. The table includes the above-mentioned fourth-quarter results

  17. EVALUATION OF BIOTIC AND TREATMENT FACTORS RELATING TO BACTERIAL CONTROL OF ZEBRA MUSSELS

    Energy Technology Data Exchange (ETDEWEB)

    Daniel P. Molloy

    2002-04-30

    Testing over the last quarter has indicated the following regarding control of zebra mussels with bacterium Pseudomonas fluorescens strain CL0145A: (1) the concentration of bacteria suspended in water is directly correlated with mussel kill; (2) the ratio of bacterial mass per mussel, if too low, could limit mussel kill; a treatment must be done at a high enough ratio so that mussels do not deplete all the suspended bacteria before the end of the desired exposure period; (3) bacteria appear to lose almost all their toxicity after suspension for 24 hr in highly oxygenated water; (4) in a recirculating pipe system, the same percentage mussel kill will be achieved irrespective of whether all the bacteria are applied at once or divided up and applied intermittently in smaller quantities over a 10-hr period. Since this is the fourth quarterly report, a summation of all test results over the last twelve months is provided as a table in this report. The table includes the above-mentioned fourth-quarter results.

  18. Social experience affects neuronal responses to male calls in adult female zebra finches.

    Science.gov (United States)

    Menardy, F; Touiki, K; Dutrieux, G; Bozon, B; Vignal, C; Mathevon, N; Del Negro, C

    2012-04-01

    Plasticity studies have consistently shown that behavioural relevance can change the neural representation of sounds in the auditory system, but what occurs in the context of natural acoustic communication where significance could be acquired through social interaction remains to be explored. The zebra finch, a highly social songbird species that forms lifelong pair bonds and uses a vocalization, the distance call, to identify its mate, offers an opportunity to address this issue. Here, we recorded spiking activity in females while presenting distance calls that differed in their degree of familiarity: calls produced by the mate, by a familiar male, or by an unfamiliar male. We focused on the caudomedial nidopallium (NCM), a secondary auditory forebrain region. Both the mate's call and the familiar call evoked responses that differed in magnitude from responses to the unfamiliar call. This distinction between responses was seen both in single unit recordings from anesthetized females and in multiunit recordings from awake freely moving females. In contrast, control females that had not heard them previously displayed responses of similar magnitudes to all three calls. In addition, more cells showed highly selective responses in mated than in control females, suggesting that experience-dependent plasticity in call-evoked responses resulted in enhanced discrimination of auditory stimuli. Our results as a whole demonstrate major changes in the representation of natural vocalizations in the NCM within the context of individual recognition. The functional properties of NCM neurons may thus change continuously to adapt to the social environment. PMID:22512260

  19. A Very Small and Super Strong Zebra Pattern Burst at the Beginning of a Solar Flare

    Science.gov (United States)

    Tan, Baolin; Tan, Chengming; Zhang, Yin; Huang, Jing; Mészárosová, Hana; Karlický, Marian; Yan, Yihua

    2014-08-01

    Microwave emission with spectral zebra pattern structures (ZPs) is frequently observed in solar flares and the Crab pulsar. The previous observations show that ZP is a structure only overlapped on the underlying broadband continuum with slight increments and decrements. This work reports an unusually strong ZP burst occurring at the beginning of a solar flare observed simultaneously by two radio telescopes located in China and the Czech Republic and by the EUV telescope on board NASA's satellite Solar Dynamics Observatory on 2013 April 11. It is a very short and super strong explosion whose intensity exceeds several times that of the underlying flaring broadband continuum emission, lasting for just 18 s. EUV images show that the flare starts from several small flare bursting points (FBPs). There is a sudden EUV flash with extra enhancement in one of these FBPs during the ZP burst. Analysis indicates that the ZP burst accompanying an EUV flash is an unusual explosion revealing a strong coherent process with rapid particle acceleration, violent energy release, and fast plasma heating simultaneously in a small region with a short duration just at the beginning of the flare.

  20. 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.

  1. Mitochondrial uncoupling as a regulator of life-history trajectories in birds: an experimental study in the zebra finch.

    Science.gov (United States)

    Stier, Antoine; Bize, Pierre; Roussel, Damien; Schull, Quentin; Massemin, Sylvie; Criscuolo, François

    2014-10-01

    Mitochondria have a fundamental role in the transduction of energy from food into ATP. The coupling between food oxidation and ATP production is never perfect, but may nevertheless be of evolutionary significance. The 'uncoupling to survive' hypothesis suggests that 'mild' mitochondrial uncoupling evolved as a protective mechanism against the excessive production of damaging reactive oxygen species (ROS). Because resource allocation and ROS production are thought to shape animal life histories, alternative life-history trajectories might be driven by individual variation in the degree of mitochondrial uncoupling. We tested this hypothesis in a small bird species, the zebra finch (Taeniopygia guttata), by treating adults with the artificial mitochondrial uncoupler 2,4-dinitrophenol (DNP) over a 32-month period. In agreement with our expectations, the uncoupling treatment increased metabolic rate. However, we found no evidence that treated birds enjoyed lower oxidative stress levels or greater survival rates, in contrast to previous results in other taxa. In vitro experiments revealed lower sensitivity of ROS production to DNP in mitochondria isolated from skeletal muscles of zebra finch than mouse. In addition, we found significant reductions in the number of eggs laid and in the inflammatory immune response in treated birds. Altogether, our data suggest that the 'uncoupling to survive' hypothesis may not be applicable for zebra finches, presumably because of lower effects of mitochondrial uncoupling on mitochondrial ROS production in birds than in mammals. Nevertheless, mitochondrial uncoupling appeared to be a potential life-history regulator of traits such as fecundity and immunity at adulthood, even with food supplied ad libitum. PMID:25063856

  2. Underwater cleaning techniqued used for removal of zebra mussels at the FitzPatrick Nuclear Power Plant

    International Nuclear Information System (INIS)

    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 housingsn. 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 ft2 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

  3. Metallothionein mRNA induction is correlated with the decrease of DNA strand breaks in cadmium exposed zebra mussels

    OpenAIRE

    Vincent-hubert, Francoise; Chatel, Amelie; Gourlay-france, Catherine

    2014-01-01

    We have previously shown that cadmium (Cd) and Benzo[a]pyrene (BaP) induced early DNA damages in zebra mussels, and that the level of DNA strand breaks (SB) returned to a basal level after 3 days of exposure to Cd. The aim of the present study was to go further in the mechanisms of Cd and BaP detoxification. For that purpose, expression of genes encoding for metallothionein (MT), Aryl Hydrocarbon Receptor (AHR), P-gP, catalase, glutathione S-transferase and Heat shock protein 70 (HSP70) prote...

  4. PAW [Physics Analysis Workstation] at Fermilab: CORE based graphics implementation of HIGZ [High Level Interface to Graphics and Zebra

    International Nuclear Information System (INIS)

    The Physics Analysis Workstation system (PAW) is primarily intended to be the last link in the analysis chain of experimental data. The graphical part of PAW is based on HIGZ (High Level Interface to Graphics and Zebra), which is based on the OSI and ANSI standard Graphics Kernel System (GKS). HIGZ is written in the context of PAW. At Fermilab, the CORE based graphics system DI-3000 by Precision Visuals Inc., is widely used in the analysis of experimental data. The graphical part of the PAW routines has been totally rewritten and implemented in the Fermilab environment. 3 refs

  5. Pauses enhance chunk recognition in song element strings by zebra finches.

    Science.gov (United States)

    Spierings, Michelle; de Weger, Anouk; Ten Cate, Carel

    2015-07-01

    When learning a language, it is crucial to know which syllables of a continuous sound string belong together as words. Human infants achieve this by attending to pauses between words or to the co-occurrence of syllables. It is not only humans that can segment a continuous string. Songbirds learning their song tend to copy 'chunks' from one or more tutors' songs and combine these into their own song. In the tutor songs, these chunks are often separated by pauses and a high co-occurrence of elements, suggesting that these features affect chunking and song learning. We examined experimentally whether the presence of pauses and element co-occurrence affect the ability of adult zebra finches to discriminate strings of song elements. Using a go/no-go design, two groups of birds were trained to discriminate between two strings. In one group (Pause-group), pauses were inserted between co-occurring element triplets in the strings, and in the other group (No-pause group), both strings were continuous. After making a correct discrimination, an individual proceeded to a reversal training using string segments. Segments were element triplets consistent in co-occurrence, triplets that were partly consistent in composition and triplets consisting of elements that did not co-occur in the strings. The Pause-group was faster in discriminating between the two strings. This group also responded differently to consistent triplets in the reversal training, compared to inconsistent triplets. The No-pause group did not differentiate among the triplet types. These results indicate that pauses in strings of song elements aid song discrimination and memorization of co-occurring element groups. PMID:25771964

  6. Effects of prenatal testosterone exposure on antioxidant status and bill color in adult zebra finches.

    Science.gov (United States)

    Tobler, Michael; Sandell, Maria I; Chiriac, Sandra; Hasselquist, Dennis

    2013-01-01

    Permanent offspring modification through maternal hormone transfer is thought to be a tool for mothers to influence life-history trajectories of individual offspring. In birds, yolk hormones influence numerous aspects of the offspring's physiology, including antioxidant status, an important physiological measure that is linked to growth, reproductive effort, and survival. While it is evident that yolk hormones can affect antioxidant status of nestlings, it is not known whether their effect extends beyond the nestling stage. In this study, we use the zebra finch (Taeniopygia guttata) to test experimentally whether exposure to elevated yolk testosterone (T) levels can result in long-term effects on antioxidant status and traits likely to be associated with this measure. Our data show a significant but sex-specific effect with respect to a period from fledging to the age of 7 mo; T males had higher antioxidant status than control males, whereas antioxidant levels did not differ among females and were intermediate compared with the two male groups. Bill color, a trait associated with carotenoids (a specific group of antioxidants) and known to be under the control of circulating levels of T, was not affected by our yolk T manipulation. Bill color (alone or in covariation with egg treatment or sex) did not predict immune responsiveness or antioxidant status. Moreover, there was only weak evidence that antioxidant status predicted the strength of different immune responses. Antioxidant status (in covariation with egg treatment and sex) predicted levels of circulating total antibody levels but did not predict the strength of cell-mediated and humoral immune responses. Our results suggest that yolk T affects antioxidant status independently of these other traits. PMID:23629883

  7. Zebra Mussel Farming in the Szczecin (Oder Lagoon: Water-Quality Objectives and Cost-Effectiveness

    Directory of Open Access Journals (Sweden)

    Thomas Neumann

    2012-06-01

    Full Text Available The Oder (Szczecin Lagoon in the southern Baltic Sea is a heavily eutrophicated and degraded coastal ecosystem. We applied a systems approach framework to critically evaluate whether existing water-management measures achieve water-quality objectives for the river and lagoon systems. Our simulations reveal that the existing water-quality objectives for the river and the coastal waters are not sufficiently complementary. We suggest new water-quality threshold concentrations, which are in agreement with the European Water Framework Directive, and we calculate acceptable maximum nutrient loads for the Oder River. These calculations suggest that external nutrient-load reductions in the river basin alone seem insufficient to achieve good water quality in the lagoon. A comprehensive eutrophication management approach should also include internal nutrient-retention and nutrient-removal measures in the lagoon. We focus on mussel farming, i.e., that of zebra mussels, Dreissena polymorpha, because they are efficient in removing nutrients and improving water transparency in the Oder Lagoon. For this purpose, the ecosystem model ERGOM is extended by a mussel module and an economic model. The economic model describes costs and benefits of mussel cultivation depending on the the farm size. We included additional potential sources of income such as water-quality tax or emission certificates. The simulations show that mussel farming in the lagoon is a suitable supportive measure and, at a load-reduction target of 50% or more, it is a cost-efficient measure for removing nutrients and for implementing the Baltic Sea Action Plan. In the Oder Lagoon, mussel farming could potentially remove nearly 1000 t of N (70 t of P/year, or about 2% of the present N and P loads, and it would have the additional benefit of improving water transparency.

  8. The complete genome sequence of 'Candidatus Liberibacter solanacearum', the bacterium associated with potato zebra chip disease.

    Science.gov (United States)

    Lin, Hong; Lou, Binghai; Glynn, Jonathan M; Doddapaneni, Harshavardhan; Civerolo, Edwin L; Chen, Chuanwu; Duan, Yongping; Zhou, Lijuan; Vahling, Cheryl M

    2011-01-01

    Zebra Chip (ZC) is an emerging plant disease that causes aboveground decline of potato shoots and generally results in unusable tubers. This disease has led to multi-million dollar losses for growers in the central and western United States over the past decade and impacts the livelihood of potato farmers in Mexico and New Zealand. ZC is associated with 'Candidatus Liberibacter solanacearum', a fastidious alpha-proteobacterium that is transmitted by a phloem-feeding psyllid vector, Bactericera cockerelli Sulc. Research on this disease has been hampered by a lack of robust culture methods and paucity of genome sequence information for 'Ca. L. solanacearum'. Here we present the sequence of the 1.26 Mbp metagenome of 'Ca. L. solanacearum', based on DNA isolated from potato psyllids. The coding inventory of the 'Ca. L. solanacearum' genome was analyzed and compared to related Rhizobiaceae to better understand 'Ca. L. solanacearum' physiology and identify potential targets to develop improved treatment strategies. This analysis revealed a number of unique transporters and pathways, all potentially contributing to ZC pathogenesis. Some of these factors may have been acquired through horizontal gene transfer. Taxonomically, 'Ca. L. solanacearum' is related to 'Ca. L. asiaticus', a suspected causative agent of citrus huanglongbing, yet many genome rearrangements and several gene gains/losses are evident when comparing these two Liberibacter. species. Relative to 'Ca. L. asiaticus', 'Ca. L. solanacearum' probably has reduced capacity for nucleic acid modification, increased amino acid and vitamin biosynthesis functionalities, and gained a high-affinity iron transport system characteristic of several pathogenic microbes. PMID:21552483

  9. The vegetation of the farms Ingleside and Welgedacht of the Mountain Zebra National Park, Eastern Cape

    Directory of Open Access Journals (Sweden)

    H. Bezuidenhout

    2005-12-01

    Full Text Available South Africa is well known for its semi-arid lowland areas that have a distinct flora and species composition. Because ecosystems react differently to different management practices, it is important that a description and classification of the vegetation of an area be done. As part of a vegetation survey programme for the newly acquired farms incorporated into the Mountain Zebra National Park, the vegetation of the Ingleside and Welgedacht sections were surveyed following the Braun-Blanquet approach. From a TWINSPAN classification, refined by Braun-Blanquet procedures, 10 shrub and grassland plant communities, which can be grouped into seven major groups, were identified. A classification and description of these communities, as well as a vegetation map are presented. The diagnostic species as well as the prominent and less conspicuous species of the tree, shrub, herb and grass strata are outlined. The area generally comprises lowland communities and higher-lying communities. The lower-lying communities consist mainly of two communities and comprise the largest proportion of the area in hectares. In contrast, the higher-lying communities are more diverse with specific habitats. Using the Ecological Index Method the veld condition and grazing capacity were calculated for each community and the total study area. Large sections of the lowland areas are overgrazed due to previous farming grazing practices while the higher-lying areas that were less accessible to the animals are in a slightly better condition. Overall this has resulted in the area generally being degraded within a high grazing capacity of 30.1 ha/LSU.

  10. Vegetation description of the Doornhoek section of the Mountain Zebra National Park (MZNP), South Africa

    Scientific Electronic Library Online (English)

    Hugo, Bezuidenhout; Leslie R., Brown.

    Full Text Available The Mountain Zebra National Park (MZNP) has been extended over the last couple of years. One of the newly procured areas is the Doornhoek section, which had been adjacent to the park. To develop scientifically sound management programmes for conservation areas, it is essential that an inventory of t [...] heir natural resources be undertaken. The aim of this study was to classify, describe and map the vegetation of the Doornhoek section of the park. The floristic data were analysed in accordance with the Braun-Blanquet procedures using the BBPC suite. The data analysis resulted in the identification of eight communities, which can be grouped into seven major community types (Rhus lucida-Buddleja glomerata Shrubland, Rhigozum obovatum-Rhus longispina Shrubland, Helichrysum dregeanum-Aristida diffusa Grassland, Pentzia globosa-Enneapogon scoparius Grassland, Aristida adscensionus-Pentzia globosa Grassland, Cadaba aphylla-Acacia karroo Woodland and Lycium oxycarpum-Acacia karroo Woodland). Four of these communities occur on the higher-lying plateau, mid-slope and crest areas, while the other four communities are located on the lower-lying mid-plateau and foot slope, along drainage lines and in valley-bottom areas. The description of the plant communities, together with the vegetation map, can serve as a basis for formulating a management programme for the larger park. Although sections of Doornhoek have been overgrazed and degraded in the past, its recent addition to the MZNP contributes to the available habitat preferred by large herbivores, such as valley bottoms, foot-slopes and plateaux.

  11. A review of Zebra techniques for the measurement of reactivity parameters, reaction rate ratios and spectra

    International Nuclear Information System (INIS)

    The paper describes the techniques devised for measurements of reactivity parameters, within-cell reaction rates and neutron energy spectra in plutonium fuelled assemblies in Zebra. Results of such measurements have played a major role in the adjustment studies leading to the new FGL5 Library. Emphasis is placed on the assessment of experimental and analytical errors which are compared with target errors set by reactor physics considerations. K-effective values are found from careful analysis of critical mass with due account of composition and dimensional uncertainties. K-infinity is obtained from cell worth measurements in small driven test-regions. Buckling values are derived from analysis of fission scan data by the experimental adjoint method using diffusion and transport theory. Foil activation, fission chamber and solid state track recorder techniques have been applied to fission rate measurements with Pu239, U235 and U238. Capture rates in U238 are obtained from thermal comparison and absolute counting methods. Spectrum measurements have been made by a range of techniques covering a total energy range from 100 ev to 6 Mev. These include time-of-flight, proton recoil, lithium-6 and double scintillator spectrometers. Comparison of different techniques over their range of overlap provide a check on the internal error estimation. Only the time-of-flight method is applicable below 5 Kev and improvements to various aspects of this technique are still needed to obtaif this technique are still needed to obtain the desired confidence in the Doppler region. Data from the spectrum measurements have been input to the LSQ adjustment scheme leading to the production of the FGL5 Data Library, the information being presented in the form of ratios of flux in adjacent groups of a 10 group set. Spectrum predictions before and after the adjustment process are compared. (author)

  12. Evaluation of Octhylphenol Effect on Development and Survival on Zebra Fish (Danio Rerio During Different Ontogenic Period

    Directory of Open Access Journals (Sweden)

    Gabi Dumitrescu

    2010-05-01

    Full Text Available This paper is part of a complex study of our research collective that studies the toxic effect of the ethinylestradiolum, and some of the polyethoxylated alkylphenols on the growth and reproduction of the Zebra fish (Danio rerio and of the common Carp (Cyprinus carpio. Our study aim was to evaluate the effect of octylphenol on growth and survival of zebra fish, from 21-115 days, and within 21-75 days of life. For this purpose, for each period under study, fishes were divided into three groups of 30 individuals, named: Lot 1 - Control, respectively lots 2 and 3, at which the administrated octylphenol concentrations were of 60 ?g L-1, respectively 100 ?g L-1. Fishes of the six groups were raised in 30-liters aquariums (30 fish / aquarium. The growth was measured by weighing and biometric measurements (total length, standard length, the length of the head, maximal height, minimal height and the mass of the body, while the surviving rate was established at the end of every period and at the end of the experiment, when we were able to calculate the total number of dead fish. Biometric study of the analysis performed in 75 days, 115 days respectively shows that octylphenol has negative influence on body development, and survival both, the highest percentage of mortality (46,66% was registered at 100 ?gL-1 concentration, between 21 -75 days.

  13. The interplay of within-species perceptual predispositions and experience during song ontogeny in zebra finches (Taeniopygia guttata).

    Science.gov (United States)

    ter Haar, Sita M; Kaemper, Wiebke; Stam, Koen; Levelt, Clara C; ten Cate, Carel

    2014-12-01

    Vocal acquisition in songbirds and humans shows many similarities, one of which is that both involve a combination of experience and perceptual predispositions. Among languages some speech sounds are shared, while others are not. This could reflect a predisposition in young infants for learning some speech sounds over others, which combines with exposure-based learning. Similarly, in songbirds, some sounds are common across populations, while others are more specific to populations or individuals. We examine whether this is also due to perceptual preferences for certain within-species element types in naive juvenile male birds, and how such preferences interact with exposure to guide subsequent song learning. We show that young zebra finches lacking previous song exposure perceptually prefer songs with more common zebra finch song element types over songs with less common elements. Next, we demonstrate that after subsequent tutoring, birds prefer tutor songs regardless of whether these contain more common or less common elements. In adulthood, birds tutored with more common elements showed a higher song similarity to their tutor song, indicating that the early bias influenced song learning. Our findings help to understand the maintenance of similarities and the presence of differences among birds' songs, their dialects and human languages. PMID:25320162

  14. Temporary inactivation of NCM, an auditory region, increases social interaction and decreases song perception in female zebra finches.

    Science.gov (United States)

    Tomaszycki, Michelle L; Blaine, Sara K

    2014-10-01

    The caudomedial nidopallium (NCM) is an important site for the storage of auditory memories, particularly song, in passerines. In zebra finches, males sing and females do not, but females use song to choose mates. The extent to which the NCM is necessary for female mate choice is not well understood. To investigate the role of NCM in partner preferences, adult female zebra finches were bilaterally implanted with chronic cannulae directed at the NCM. Lidocaine, a sodium channel blocker, or saline (control) was infused into the NCM of females using a repeated measures design. Females were then tested in 3 separate paradigms: song preference, sexual partner preference, and pairing behavior/partner preference. We hypothesized that lidocaine would increase interactions with males by decreasing song discrimination and that this would be further evident in the song discrimination task. Indeed, females, when treated with lidocaine, had no preference for males singing unaltered song over males singing distorted song. These same females, when treated with saline, demonstrated a significant preference for males singing normal song. Furthermore, females affiliated with males more after receiving lidocaine than after receiving saline in the pairing paradigm, although neither treatment led to the formation of a partner preference. Our results support the hypothesis that NCM plays an important role not only in song discrimination, but also affiliation with a male. PMID:25277702

  15. Sex-biased investment in yolk androgens depends on female quality and laying order in zebra finches (Taeniopygia guttata)

    Science.gov (United States)

    Gilbert, Lucy; Rutstein, Alison N.; Hazon, Neil; Graves, Jefferson A.

    2005-04-01

    The Trivers-Willard hypothesis predicts sex biases in parental investment according to parental condition. In addition, parents may need to sex bias their investment if there is an asymmetry between the sexes in offspring fitness under different conditions. For studying maternal differential investment, egg resources are ideal subjects because they are self contained and allocated unequivocally by the female. Recent studies show that yolk androgens can be beneficial to offspring, so here we test for sex-biased investment with maternal investment of yolk testosterone (T) in zebra finch (Taeniopygia guttata) eggs. From the Trivers-Willard hypothesis, we predicted females to invest more in male eggs in optimum circumstances (e.g. good-condition mother, early-laid egg), and more in female eggs under suboptimal conditions (e.g. poor-condition mother, late-laid egg). This latter prediction is also because in this species there is a female nestling disadvantage in poor conditions and we expected mothers to help compensate for this in female eggs. Indeed, we found more yolk T in female than male eggs. Moreover, in accordance with our predictions, yolk T in male eggs increased with maternal quality relative to female eggs, and decreased with laying order relative to female eggs. This supports our predictions for the different needs and value of male and female offspring in zebra finches. Our results support the idea that females may use yolk androgens as a tool to adaptively manipulate the inequalities between different nestlings.

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

    Energy Technology Data Exchange (ETDEWEB)

    Konishi, M.; Akutagawa, E. (California Institute of Technology, Pasadena (USA))

    1990-05-01

    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.

  17. Measurements and calculations of ratios of effective fission cross-sections in the zero-power fast reactor, Zebra

    International Nuclear Information System (INIS)

    The comparison of measured and calculated central fission ratios provides a useful method for checking the accuracy of calculated spectra and fission cross-section data. A set of parallel plate fission chambers was specially made for Zebra. The design was based on that of Kirn's chambers used by the ZPR-III group at ANL, Idaho, and incorporated a number of improvements. In particular, the wall thickness was reduced to reduce the degradation of the spectrum. The fissile coatings in the earlier chambers were prepared by a painting technique and those in the later chambers by an electrodeposition method. The mass deposited was determined by low geometry or assay. The construction of the chambers and the method of calibration and use are described. Central fission ratios in six Zebra cores measured to an accuracy of 1-3% are compared with values computed using the FD2 data set and the CRAM or SCRAMBLE multigroup diffusion theory programmes. This comparison suggests that the calculations give too few neutrons at high energies. There is also evidence that some of the fission cross-section data used in the FD2 set is in error. (author)

  18. Karyotypic conservatism in samples of Characidium cf. zebra (Teleostei, Characiformes, Crenuchidae): physical mapping of ribosomal genes and natural triploidy

    Scientific Electronic Library Online (English)

    José Carlos, Pansonato-Alves; Claudio, Oliveira; Fausto, Foresti.

    Full Text Available Basic and molecular cytogenetic analyses were performed in specimens of Characidium cf. zebra from five collection sites located throughout the Tietê, Paranapanema and Paraguay river basins. The diploid number in specimens from all samples was 2n = 50 with a karyotype composed of 32 metacentric and [...] 18 submetacentric chromosomes in both males and females. Constitutive heterochromatin was present at the centromeric regions of all chromosomes and pair 23, had additional interstitial heterochromatic blocks on its long arms. The nucleolar organizer regions (NORs) were located on the long arms of pair 23, while the 5S rDNA sites were detected in different chromosomes among the studied samples. One specimen from the Alambari river was a natural triploid and had two extra chromosomes, resulting in 2n = 77. The remarkable karyotypic similarity among the specimens of C. cf. zebra suggests a close evolutionary relationship. On the other hand, the distinct patterns of 5S rDNA distribution may be the result of gene flow constraints during their evolutionary history.

  19. ZebraFISH: fluorescent in situ hybridization protocol and three-dimensional imaging of gene expression patterns.

    Science.gov (United States)

    Welten, Monique C M; de Haan, Simon B; van den Boogert, Niels; Noordermeer, Jasprien N; Lamers, Gerda E M; Spaink, Herman P; Meijer, Annemarie H; Verbeek, Fons J

    2006-01-01

    We present a method and protocol for fluorescent in situ hybridization (FISH) in zebrafish embryos to enable three-dimensional imaging of patterns of gene expression using confocal laser scanning microscopy. We describe the development of our protocol and the processing workflow of the three-dimensional images from the confocal microscope. We refer to this protocol as zebraFISH. FISH is based on the use of tyramide signal amplification (TSA), which results in highly sensitive and very localized fluorescent staining. The zebraFISH protocol was extensively tested and here we present a panel of five probes for genes expressed in different tissues or single cells. FISH in combination with confocal laser scanning microscopy provides an excellent tool to generate three-dimensional images of patterns of gene expression. We propose that such three-dimensional images are suitable for building a repository of gene expression patterns, complementary to our previously published three-dimensional anatomical atlas of zebrafish development (bio-imaging.liacs.nl/). Our methodology for image processing of three-dimensional confocal images allows an analytical approach to the definition of gene expression domains based on the three-dimensional anatomical atlas. PMID:18377226

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

    International Nuclear Information System (INIS)

    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

  1. 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)

    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

  2. Epi-genetics modifications induced by a depleted uranium exposure in the zebra fish

    Energy Technology Data Exchange (ETDEWEB)

    Gombeau, K.; Pereira, S.; Adam-Guillermin, C. [IRSN/PRP-ENV/SERIS/LECO (France); Bourdineaud, J.P. [UMR CNRS 5805 EPOC (France); Ravanat, J.L. [INAC/Scib UMR E3 CEA-UJF (France)

    2014-07-01

    The work presented here integrates in the general framework of assessment of effects of chronic exposure to low doses of radionuclides. This evaluation necessarily involves the study of the mechanisms of toxic action at the cellular or subcellular level, in order to better understand the processes of propagation of effects to the level of the populations or ecosystems. As such, the question of the mechanisms underlying the trans-generational effects and the adaptive capacity of organisms is central, both in humans and in animal species. Epigenetic refer to changes in gene function that do not involve changes in DNA sequence, and which are transmitted in a hereditary manner by mitosis or meiosis. The latter plays a key role in these trans-generational effects. Among these changes, DNA-methylation is one of the most studied epigenetic parameters. This work is part of a PhD, included in the European COMET project (Euratom 7. Framework Program), and focuses on epigenetic modifications induced in zebra fish after a chronic exposure to radionuclides. Male and female fishes were exposed to 2 and 20 ?g.L{sup -1} of depleted uranium for 24 days. After 7 and 24 days of exposure, brain, gonads, and eyes were collected in order to study changes in DNA methylation. In addition, genotoxicity was measured by the ?H2AX assay. The overall changes in DNA methylation were studied by AFLP-MS and HPLC-MS, in order to know if the exposure to depleted uranium changes the global status of DNA methylation. We have found a decrease in the global level of methylation in the eyes of males after 24 days of exposure, the diminution being much more important and significant at the higher concentration of exposure (11.79 ± 3.62 against 52.43 ± 3.01 for controls) This study will be refined by analyzing the methylation of specific regions of the genome, because it represent the sequences of genes involved in major physiological functions and that may be subject to variations in the methylation of the region regulating their expression. Thus, we will be able to identify target genes undergoing epigenetic changes, and linking these findings to a possible alteration of the physiological functions encoded. After this first experiment, we will have more information on the epigenetic impacts and targets of these changes following exposure to depleted uranium. Exposure of organisms to an external gamma radiation will be then performed to compare the methylation status of target genes. Document available in abstract form only. (authors)

  3. Epi-genetics modifications induced by a depleted uranium exposure in the zebra fish

    International Nuclear Information System (INIS)

    The work presented here integrates in the general framework of assessment of effects of chronic exposure to low doses of radionuclides. This evaluation necessarily involves the study of the mechanisms of toxic action at the cellular or subcellular level, in order to better understand the processes of propagation of effects to the level of the populations or ecosystems. As such, the question of the mechanisms underlying the trans-generational effects and the adaptive capacity of organisms is central, both in humans and in animal species. Epigenetic refer to changes in gene function that do not involve changes in DNA sequence, and which are transmitted in a hereditary manner by mitosis or meiosis. The latter plays a key role in these trans-generational effects. Among these changes, DNA-methylation is one of the most studied epigenetic parameters. This work is part of a PhD, included in the European COMET project (Euratom 7. Framework Program), and focuses on epigenetic modifications induced in zebra fish after a chronic exposure to radionuclides. Male and female fishes were exposed to 2 and 20 ?g.L-1 of depleted uranium for 24 days. After 7 and 24 days of exposure, brain, gonads, and eyes were collected in order to study changes in DNA methylation. In addition, genotoxicity was measured by the ?H2AX assay. The overall changes in DNA methylation were studied by AFLP-MS and HPLC-MS, in order to know if the exposure to depleted uranium changes the global status of DNA methylation. We have found a decrease in the global level of methylation in the eyes of males after 24 days of exposure, the diminution being much more important and significant at the higher concentration of exposure (11.79 ± 3.62 against 52.43 ± 3.01 for controls) This study will be refined by analyzing the methylation of specific regions of the genome, because it represent the sequences of genes involved in major physiological functions and that may be subject to variations in the methylation of the region regulating their expression. Thus, we will be able to identify target genes undergoing epigenetic changes, and linking these findings to a possible alteration of the physiological functions encoded. After this first experiment, we will have more information on the epigenetic impacts and targets of these changes following exposure to depleted uranium. Exposure of organisms to an external gamma radiation will be then performed to compare the methylation status of target genes. Document available in abstract form only. (authors)

  4. Tracheosyringeal nerve transection in juvenile male zebra finches decreases BDNF in HVC and RA and the projection between them.

    Science.gov (United States)

    Tang, Yu Ping; Wade, Juli

    2014-11-01

    This study investigated relationships among disruption of normal vocal learning, brain-derived neurotrophic factor (BDNF), and the morphology of song nuclei in juvenile male zebra finches. The tracheosyringeal nerves were bilaterally transected at post-hatching day 20-25, so that the animals could not properly develop species-typical vocalizations. BDNF protein and the projection from HVC to the robust nucleus of the arcopallium (RA) were quantified during the sensorimotor integration phase of song development. The manipulation decreased the number of BDNF cells in HVC and RA, the volume of these areas defined by BDNF labeling, and the projection from HVC to RA. BDNF was not affected in Area X or the lateral magnocellular nucleus of the anterior nidopallium (LMAN). Thus, inhibition of a bird's ability to practice and/or to hear its own typically developing song specifically diminishes BDNF expression in cortical motor regions required for song production. PMID:25219377

  5. PHA-stimulated immune-responsiveness in mercury-dosed zebra finches does not match results from environmentally exposed songbirds.

    Science.gov (United States)

    Caudill, Mitchell T; Spear, Eliza L; Varian-Ramos, Claire W; Cristol, Daniel A

    2015-04-01

    Dietary mercury exposure is associated with suppressed immune responsiveness in birds. This study examined the immune-responsiveness of domestic zebra finches (Taeniopygia guttata) experimentally exposed to mercury through their diet. We used the phytohemagglutinin (PHA) skin-swelling test to assay the effect of two modes of mercury exposure. Some finches received exposure to mercury only after reaching sexual maturity, while others were maintained on a mercury-dosed diet throughout life, including development. Each bird received one of five dietary concentrations of methylmercury cysteine (0.0, 0.3, 0.6, 1.2 or 2.4 ppm). In contrast to a study on wild songbirds at a mercury-contaminated site, we detected no relationship between mercury level and immunological response to PHA, regardless of mode of exposure. This result represents the first major difference found by our laboratory between wild birds exposed to environmental mercury and captive birds experimentally exposed to mercury. PMID:25638440

  6. Testing and applicability of the UPC-ZEBRA interferometer as a phasing system in segmented-mirror telescopes

    Science.gov (United States)

    Pintó, Agustí; Laguarta, Ferran; Artigas, Roger; Cadevall, Cristina

    2004-02-01

    In segmented-mirror telescopes, wave-front discontinuities caused by segment misalignment are a major problem because they severely degrade optical performance. While angular misalignments are usually measured with deflectometric wave-front sensors (e.g., Shack-Hartmann sensors), a number of techniques have been proposed for the measurement of vertical discontinuities (pistons). In earlier papers we presented an instrument called UPC-ZEBRA that uses a novel interferometric technique to measure piston error during the daytime with an uncertainty of 5 nm within a 30-?m range. Here we present the most representative results obtained during the testing stage and a detailed analysis of error sources. The main modifications to be introduced for the instrument's use as a phasing calibration system are also outlined.

  7. A description of the equipment for time-of-flight spectrum measurements on the fast reactor ZEBRA

    International Nuclear Information System (INIS)

    The pulsed source for the time-of-flight equipment consists of 14 MeV S-band linear electron accelerator, drift tube and water-cooled uranium-molybdenum alloy target installed on the ZEBRA lattice. Neutrons are extracted via a probe tube inserted into the core and an evacuated flight tube with counting stations at 50 m, 97 m and 200 m from the core centre. Two types of neutron detector are described and also the Perranti Argus 500 on-line computer which is used for data collection. The equipment is used for measuring the neutron energy spectra from the lowest energies up to about 1 MeV. (author)

  8. X-ray pulse shaping in experiments with planar wire arrays at the 1.6 MA Zebra generator

    International Nuclear Information System (INIS)

    The shaping of the x-ray radiation pulse is very important in both radiation physics research and Inertial Confinement Fusion studies. The novel planar wire array (PWA) was found to be the effective radiator tested at the university-scale 1.6 MA, 100 ns Zebra generator. The single PWA consists of a single row of wires that are parallel to each other, while the double planar wire array (DPWA) and triple planar wire array (TPWA) include two or three parallel plane wire rows, respectively. All multi-planar geometries resulted in a cascade-type array implosion with a complicated multi-step precursor formation before plasma stagnation. The PWAs (without additional core foam target) feature a dynamic precursor evolution that is a powerful tool for x-ray pulse shaping. The shape and timing of the x-ray pulse from different PWAs were theoretically predicted and experimentally analyzed for a variety of planar wire arrays.

  9. A comparison of SNPs and microsatellites as linkage mapping markers: lessons from the zebra finch (Taeniopygia guttata

    Directory of Open Access Journals (Sweden)

    Birkhead Tim R

    2010-04-01

    Full Text Available Abstract Background Genetic linkage maps are essential tools when searching for quantitative trait loci (QTL. To maximize genome coverage and provide an evenly spaced marker distribution a combination of different types of genetic marker are sometimes used. In this study we created linkage maps of four zebra finch (Taeniopygia guttata chromosomes (1, 1A, 2 and 9 using two types of marker, Single Nucleotide Polymorphisms (SNPs and microsatellites. To assess the effectiveness and accuracy of each kind of marker we compared maps built with each marker type separately and with both types of marker combined. Linkage map marker order was validated by making comparisons to the assembled zebra finch genome sequence. Results We showed that marker order was less reliable and linkage map lengths were inflated for microsatellite maps relative to SNP maps, apparently due to differing error rates between the two types of marker. Guidelines on how to minimise the effects of error are provided. In particular, we show that when combining both types of marker the conventional process of building linkage maps, whereby the most informative markers are added to the map first, has to be modified in order to improve map accuracy. Conclusions When using multiple types and large numbers of markers to create dense linkage maps, the least error prone loci (SNPs rather than the most informative should be used to create framework maps before the addition of other potentially more error prone markers (microsatellites. This raises questions about the accuracy of marker order and predicted recombination rates in previous microsatellite linkage maps which were created using the conventional building process, however, provided suitable error detection strategies are followed microsatellite-based maps can continue to be regarded as reasonably reliable.

  10. Features of the Retinotopic Representation in the Visual Wulst of a Laterally Eyed Bird, the Zebra Finch (Taeniopygia guttata).

    Science.gov (United States)

    Michael, Neethu; Löwel, Siegrid; Bischof, Hans-Joachim

    2015-01-01

    The visual wulst of the zebra finch comprises at least two retinotopic maps of the contralateral eye. As yet, it is not known how much of the visual field is represented in the wulst neuronal maps, how the organization of the maps is related to the retinal architecture, and how information from the ipsilateral eye is involved in the activation of the wulst. Here, we have used autofluorescent flavoprotein imaging and classical anatomical methods to investigate such characteristics of the most posterior map of the multiple retinotopic representations. We found that the visual wulst can be activated by visual stimuli from a large part of the visual field of the contralateral eye. Horizontally, the visual field representation extended from -5° beyond the beak tip up to +125° laterally. Vertically, a small strip from -10° below to about +25° above the horizon activated the visual wulst. Although retinal ganglion cells had a much higher density around the fovea and along a strip extending from the fovea towards the beak tip, these areas were not overrepresented in the wulst map. The wulst area activated from the foveal region of the ipsilateral eye, overlapped substantially with the middle of the three contralaterally activated regions in the visual wulst, and partially with the other two. Visual wulst activity evoked by stimulation of the frontal visual field was stronger with contralateral than with binocular stimulation. This confirms earlier electrophysiological studies indicating an inhibitory influence of the activation of the ipsilateral eye on wulst activity elicited by stimulating the contralateral eye. The lack of a foveal overrepresentation suggests that identification of objects may not be the primary task of the zebra finch visual wulst. Instead, this brain area may be involved in the processing of visual information necessary for spatial orientation. PMID:25853253

  11. Temperature and Ca2+-dependence of the sarcoplasmic reticulum Ca2(+)-ATPase in haddock, salmon, rainbow trout and zebra cichlid

    DEFF Research Database (Denmark)

    Godiksen, Helene; Jessen, Flemming

    2002-01-01

    Temperature dependence of Ca2+-ATPase from the sarcoplasmic reticulum (SR) in rabbit muscle has been widely studied, and it is generally accepted that a break point in Arrhenius plot exist at approximately 20 degreesC. Whether the break point arises as a result of temperature dependent changes in the enzyme or its membrane lipid environment is still a matter of discussion. In this study we compared the temperature dependence and Ca2+-dependence of SR Ca2+-ATPase in haddock (Melanogrammus aeglefinus), salmon (Salmo, salar), rainbow trout (Oncorhynchus mykiss) and zebra cichlid (Cichlasoma nigrofasciatum). The Arrhenius plot of zebra cichlid showed a break point at 20 degreesC, and the haddock Arrhenius plot was non-linear with pronounced changes in slope in the. temperature area, 6-14 degreesC. In Arrhenius plot from both salmon and rainbow trout a plateau exists with an almost constant SR Ca2+- ATPase activity. The temperature range of the plateau was 14-21 and 18-25 degreesC in salmon and rainbow trout, respectively. Ca2+-dependence in the four different fish species investigated was very similar with half maximal activation (K-0.5) between 0.2 and 0.6 muM and half maximal inhibition (I-0.5) between 60 and 250 muM. Results indicated that interaction between SR Ca2+-ATPase and its lipid environment may play an important role for the different Arrhenius plot of the different types of fish species investigated. (C) 2002 Elsevier Science Inc. All rights reserved.

  12. Metabolic programming of zebra fish Danio rerio uncovered. Physiological performance as explained by dynamic energy budget theory and life-cycle consequence of uranium induced perturbations

    International Nuclear Information System (INIS)

    The aim of this dissertation is to characterize the toxicity of uranium on the metabolism of zebra fish, nio rerio. The first three chapters of this manuscript are dedicated to characterizing the blank metabolism of zebra fish. I used the Dynamic Energy Budget (deb) theory for this characterisation; it is presently the only theory that covers the full life cycle of the organism and quantifies feeding, assimilation, growth, reproduction, maturation, maintenance and ageing. Any metabolic effect of uranium should appear as effects on one or more of these fundamental processes. Since the life span of zebra fish is some four and a half years, and larger individuals respond slower to chemical stress, the focus was on the early life stages. Considerable breakthroughs in the quantification of zebra fish development, growth and reproduction have been made. It turned out the zebra fish accelerates its metabolism after birth till metamorphosis, when acceleration ceases. This process is seen in some, but not all, species of fish. Another striking conclusion was that somatic maintenance was much higher than is typical for fish. We don't yet have an explanation for this funding. Further it turned out that the details of reproduction matter: allocation to reproduction (in adults) accumulates in a reproduction buffer and this buffer is used to prepare batches of eggs. We needed to detail this preparation process to understand how zebra fish can eliminate uranium via eggs. Deb theory specifies that a particular developmental stage (birth, metamorphosis, puberty) is reached at specified levels of maturity. For different temperatures and food levels, that can occur at different ages and body sizes. We extended this idea to include all the described morphologically defined developmental stages of the zebra fish in the literature; the observed variations in ages and body sizes can now be explained by deb theory. To test if deb theory can also explain perturbations of maturation, we studied developmental patterns in two types of taxonomically related frog species of similar body size. One type shows a typical developmental pattern as embryo, feeding tadpole and juvenile frog. The other type shows, after hatching, but before birth (= start of feeding) a significant acceleration of maturation, which is visible as an increased respiration and retarded growth, with big effects on size at a given developmental stage. This acceleration is reduced after metamorphosis but compared to the standard type of frog, it takes considerable time to catch up in growth. All these changes could be captured accurately with deb theory by a temporary change in a single parameter: the fraction of mobilised reserve that is allocated to somatic maintenance plus growth, as opposed to maturity maintenance plus maturation. The conclusion is that the observed perturbations of maturation and the age and size variations at various developmental stages provide strong support for how deb theory incorporates maturation. We not only required detail on maturation but also on starvation, especially in the early juvenile stages. The problem is that, according to deb theory, maintenance is paid from mobilised reserve, but when food is scarce or absent, reserve becomes depleted and maintenance can no longer be paid from mobilised reserve. We included more detail on what happens exactly under such conditions. More specifically we modelled the processes of rejuvenation and shrinking (of structure) and their consequence for hazard rate. We managed to capture observed size and survival trajectories of fish fry under controlled starving conditions. These processes are not only important to capture effects of uranium on feeding, but have a much wider ecological significance in field situations. As a result of my work, there is now a formal basis for understanding (and predicting) how the physiological performance of zebra fish relates to food intake. The model was used to detect uranium induced eco-physiological deviations from the blank. For this purpose we developed a dynamic model for

  13. Differential coexpression of FoxP1, FoxP2, and FoxP4 in the Zebra Finch (Taeniopygia guttata) song system.

    Science.gov (United States)

    Mendoza, Ezequiel; Tokarev, Kirill; Düring, Daniel N; Retamosa, Eva Camarillo; Weiss, Michael; Arpenik, Nshdejan; Scharff, Constance

    2015-06-15

    Heterozygous disruptions of the Forkhead transcription factor FoxP2 impair acquisition of speech and language. Experimental downregulation in brain region Area X of the avian ortholog FoxP2 disrupts song learning in juvenile male zebra finches. In vitro, transcriptional activity of FoxP2 requires dimerization with itself or with paralogs FoxP1 and FoxP4. Whether this is the case in vivo is unknown. To provide the means for future functional studies we cloned FoxP4 from zebra finches and compared regional and cellular coexpression of FoxP1, FoxP2, and FoxP4 mRNA and protein in brains of juvenile and adult male zebra finches. In the telencephalic song nuclei HVC, RA, and Area X, the three investigated FoxPs were either expressed alone or occurred in specific combinations with each other, as shown by double in situ hybridization and triple immunohistochemistry. FoxP1 and FoxP4 but not FoxP2 were expressed in RA and in the HVCRA and HVCX projection neurons. In Area X and the surrounding striatum the density of neurons expressing all three FoxPs together or FoxP1 and FoxP4 together was significantly higher than the density of neurons expressing other combinations. Interestingly, the proportions of Area X neurons expressing particular combinations of FoxPs remained constant at all ages. In addition, FoxP-expressing neurons in adult Area X express dopamine receptors 1A, 1B, and 2. Together, these data provide the first evidence that Area X neurons can coexpress all avian FoxP subfamily members, thus allowing for a variety of regulatory possibilities via heterodimerization that could impact song behavior in zebra finches. J. Comp. Neurol. 523:1318-1340, 2015. © 2014 Wiley Periodicals, Inc. PMID:25556631

  14. Evaluation of an Immunofiltration Assay That Detects Immunoglobulin M Antibodies against the ZEBRA Protein for the Diagnosis of Epstein-Barr Virus Infectious Mononucleosis in Immunocompetent Patients ?

    OpenAIRE

    Bravo, Dayana; Mun?oz-cobo, Beatriz; Costa, Elisa; Clari, M. Angeles; Tormo, Nuria; Navarro, David

    2009-01-01

    The performance of an immunofiltration assay (IMFA) that detects immunoglobulin M (IgM) antibodies to the Epstein-Barr virus (EBV) ZEBRA (BamHI Z EBV replication activator) protein was evaluated for the diagnosis of EBV infectious mononucleosis (IM) in immunocompetent patients. The test panel consisted of 47 sera displaying an EBV-specific antibody profile compatible with an acute primary EBV infection from patients with clinical and biological features of EBV IM, 20 sera from healthy individ...

  15. Spatial ability is impaired and hippocampal mineralocorticoid receptor mRNA expression reduced in zebra finches (Taeniopygia guttata) selected for acute high corticosterone response to stress

    OpenAIRE

    Hodgson, Zoe? G.; Meddle, Simone L.; Roberts, Mark L.; Buchanan, Katherine L.; Evans, Matthew R.; Metzdorf, Reinhold; Gahr, Manfred; Healy, Susan D.

    2006-01-01

    In mammals, stress hormones have profound influences on spatial learning and memory. Here, we investigated whether glucocorticoids influence cognitive abilities in birds by testing a line of zebra finches selectively bred to respond to an acute stressor with high plasma corticosterone (CORT) levels. Cognitive performance was assessed by spatial and visual one-trial associative memory tasks. Task performance in the high CORT birds was compared with that of the random-bred birds from a control ...

  16. Living with the Past: Nutritional Stress in Juvenile Males Has Immediate Effects on their Plumage Ornaments and on Adult Attractiveness in Zebra Finches

    OpenAIRE

    Naguib, Marc; Nemitz, Andrea

    2007-01-01

    The environmental conditions individuals experience during early development are well known to have fundamental effects on a variety of fitness-relevant traits. Although it is evident that the earliest developmental stages have large effects on fitness, other developmental stages, such as the period when secondary sexual characters develop, might also exert a profound effect on fitness components. Here we show experimentally in male zebra finches, Taeniopygia guttata, that nutritional conditi...

  17. Prevalencia de Staphylococcus aureus, Vibrio spp. y enterobacterias en carne de pepitona, Arca zebra, comercializada en Cumaná, Venezuela / Prevalence of Staphylococcus aureus, Vibrio spp., and enterobacteria in pepitona, Arca zebra, commercialized in Cumaná, Venezuela

    Scientific Electronic Library Online (English)

    Daniel, Muñoz; Crucita, Graü de Marín; Carlos, Martínez; Hilda, Marval; Aracelis, Zerpa.

    2008-12-01

    Full Text Available La pepitona, Arca zebra, (Mollusca: Bivalvia: Arcidae) es un producto de consumo masivo en el oriente de Venezuela. Se recolectaron mensualmente (marzo a septiembre 2004), muestras de pepitonas provenientes de expendios del Mercado Municipal de Cumaná, con el fin de determinar su condición higiénico [...] -sanitaria. Se efectuaron recuentos en placa de Staphylococcus aureus, enterobacterias y detección de Vibrio spp. La identificación se realizó utilizando pruebas bioquímicas diferenciales basadas en la actividad metabólica de cada cepa aislada. Los análisis revelaron contaminación por S. aureus y enterobacterias en las muestras de carne de pepitonas, con valores promedio de 1,8 x 10² a 6,4 x 10³ y 2,5 x 10² a 5,4 x 10³ UFC/g, respectivamente. Se aislaron 61 cepas de S. aureus, de las cuales 37,7% resultaron ser positivas a la prueba de coagulasa y 42,6% a la DNAsa. Se identificaron diez especies pertenecientes a la familia Enterobacteriaceae, siendo la predominante Escherichia coli con 25% de prevalencia. También fueron identificadas las siguientes especies de Vibrio: V. alginolyticus, V. parahaemolyticus, V. metchinikovii, V. fluvialis y V. mimicus. Se demostró la presencia de patógenos en carne de pepitona libremente expendida en el Mercado Municipal de Cumaná. Abstract in english Pepitona or turkey wing, Arca zebra (Mollusca: Bivalvia: Arcidae), is a product of massive consumption in eastern Venezuela. Monthly samples (march to september 2004) of pepitona meat were taken from vending places in the Cumana Municipal Market, in order to determine their hygienic conditions. Plat [...] e cultures of Staphylococcus aureus and enterobacteriae, and detection of Vibrio spp. were made. The identification was made using differential biochemical tests based upon the metabolic activity of each isolated strain. The analyses showed a high degree of contamination by S. aureus and enterobacteria in samples of pepitona meat, with average values 1.8 x 10² to 6.4 x 10³, and 2.5 x 10² to 5.4 x 10³ CFU/g, respectively. A total number of 61 strains of S. aureus were isolated, of which 39.1% yielded positive to the coagulase test and 41.7% to the DNAse test. Ten species of the family Enterobacteriaceae were identified, being Escherichia coli the most predominant with 25% prevalence. The following Vibrio species were identified: V. alginolyticus, V. parahaemolyticus, V. metchinikovii, V. fluvialis and V. mimicus. The presence of pathogens in pepitona meat freely sold to the public in the Municipal Market of Cumaná was demonstrated.

  18. Contribución al conocimiento de los macromoluscos bentónicos asociados a la pepitona, Arca zebra (Swainson, 1833), del banco natural de Chacopata, Península de Araya, Venezuela / Contribution to the knowledge of benthonic macromollusks associated to pepitona, Arca zebra (Swainson, 1833), in the natural bank of Chacopata, Araya Peninsula, Venezuela

    Scientific Electronic Library Online (English)

    Licet, Berenice; Acosta, Vanesa; Prieto, Antulio; Garcia, Natividad.

    2009-03-01

    Full Text Available Como parte de un programa de monitoreo de áreas marinas del norte del estado Sucre, Venezuela, se analizó la diversidad malacológica de los macromoluscos asociados a la pepitona, Arca zebra, ubicado en el banco natural de Chacopata, desde enero hasta marzo 2006. Se identificaron un total de 31 espec [...] ies pertenecientes a 21 familias y 4 clases de moluscos, que incluyeron 12 especies de bivalvos, 17 gasterópodos, un cefalópodo y un poliplacóforo. Los parámetros de diversidad numérica fueron bajos (H’ = 1,907 a 2,034 bits/ind; J’ = 0,591 a 0,649, IS = 0,209 a 0,258) mientras que la dominancia osciló entre 35,9 y 46,4%. El índice ? de la serie logarítmica mensual fluctúo entre 4,819 y 6,917. La escasa variación mensual de la diversidad confirma investigaciones previas e indican que la estructura comunitaria es estable. Se determinaron 19 especies constantes siendo las mas abundantes los bivalvos Arca zebra, Chama congregata, Chama sarda y Chama sarda, mientras que en los gasterópodos fueron Chicoreus brevifrons y Crepidula ausitulata. Arca zebra fue la especie dominante en numero, indicando que desempeña el papel más importante en la comunidad como un eficiente filtrador, lo cual le permite soportar una de las pesquerías más importantes de la región. Abstract in english As part of a monitoring program of the marine areas at northern of Sucre state, Venezuela, we examined the malacological diversity of macromollusk associated to ark shell, Arca zebra, located in the natural bank of Chacopata. Monthly sampling was made from January to March 2006. A total of 31 specie [...] s were identified belonging to 21 families of 4 classes of mollusk that included 12 species of bivalves, 17 gastropods, one cephalopods and one poliplacophoro. Parameters of numeric diversity were low (H’ = 1.907 to 2.034 bits/ind; J’= 0.591 to 0.649; IS = 0.209 to 0.258), while the dominance oscillated between 35.99 and 43.61%. Alpha index of the logarithmic series model fluctuated between 4.819 and 6.917. The scarce monthly variation confirms previous research and they indicate that the community structure is stable. Fourteen constant species were determined being those more abundant the bivalves Arca zebra, Chama congregate y Chama sarda, while the gastropods were Chicoreus brevifrons and Crepidula ausitulata. Arca zebra was the dominant species in number and occupied a central role in the community, supporting one of the most important fisheries in the area.

  19. Metallothionein mRNA induction is correlated with the decrease of DNA strand breaks in cadmium exposed zebra mussels.

    Science.gov (United States)

    Vincent-Hubert, Françoise; Châtel, Amélie; Gourlay-Francé, Catherine

    2014-05-15

    We have previously shown that cadmium (Cd) and benzo[a]pyrene (BaP) induced early DNA damages in zebra mussels, and that the level of DNA strand breaks (SB) returned to a basal level after 3 days of exposure to Cd. The aim of the present study was to go further in the mechanisms of Cd and BaP detoxification. For that purpose, expression of genes encoding for metallothionein (MT), aryl hydrocarbon receptor (AHR), P-gp, catalase, glutathione S-transferase and heat shock protein 70 (HSP70) proteins have been measured using RT-qPCR. Data reported here show that Cd is a strong inducer of MT and HSP70 genes, and that BaP is a strong inducer of P-gp and AHR genes. Exposure to Cd and BaP resulted in moderate changes in antioxidant enzymes mRNA. Since the increase of MT mRNA occurred when the DNA SB level returned to its basal level, we can suggest that MT is implicated in cadmium detoxification. PMID:24681118

  20. Spectroscopic modeling of radiation from Cu and Mo X-pinches produced on the UNR 1 MA Zebra generator

    International Nuclear Information System (INIS)

    X-pinches are a source for studying radiative properties of plasmas of very small sizes, high densities and temperatures applicable to high-energy density plasmas such as dense Z-pinches. Recently, spatially resolved and spatially integrated X-ray spectral data have been accumulated during Mo and Cu X-pinch experiments on the Zebra generator. During these experiments configurations, other then the 2-wire X-pinches, such as 4-wire X-pinches and asymmetric X-pinches have been spectroscopically studied and computationally analyzed. We present here modeling of the K-shell and L-shell radiation from Cu X-pinches with two and four wires and the comparison with experimental spectra. L-shell radiation from symmetric and asymmetric Mo X-pinches with two wires and X-pinches with four wires have also been analyzed and compared. Dependence of the plasma spatial structure, temperature, and density on wire materials and load configurations are discussed

  1. 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.

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

    Directory of Open Access Journals (Sweden)

    DennisEckmeier

    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.

  3. The presence of an audience modulates responses to familiar call stimuli in the male zebra finch forebrain.

    Science.gov (United States)

    Menardy, F; Giret, N; Del Negro, C

    2014-11-01

    The ability to recognize familiar individuals is crucial for establishing social relationships. The zebra finch, a highly social songbird species that forms lifelong pair bonds, uses a vocalization, the distance call, to identify its mate. However, in males, this ability depends on social conditions, requiring the presence of an audience. To evaluate whether the presence of bystanders modulates the auditory processing underlying recognition abilities, we assessed, by using a lightweight telemetry system, whether electrophysiological responses driven by familiar and unfamiliar female calls in a high-level auditory area [the caudomedial nidopallium (NCM)] were modulated by the presence of conspecific males. Males had experienced the call of their mate for several months and the call of a familiar female for several days. When they were exposed to female calls in the presence of two male conspecifics, NCM neurons showed greater responses to the playback of familiar female calls, including the mate's call, than to unfamiliar ones. In contrast, no such discrimination was observed in males when they were alone or when call-evoked responses were collected under anaesthesia. Together, these results suggest that NCM neuronal activity is profoundly influenced by social conditions, providing new evidence that the properties of NCM neurons are not simply determined by the acoustic structure of auditory stimuli. They also show that neurons in the NCM form part of a network that can be shaped by experience and that probably plays an important role in the emergence of communication sound recognition. PMID:25145963

  4. Histological Changes Induced in Gonads, Liver and Kidney of Zebra Fish (Danio Rerio Under the Effect Octylphenol (OP

    Directory of Open Access Journals (Sweden)

    Gabi Dumitrescu

    2010-05-01

    Full Text Available World-wide researches during the last years are focused upon the negative effects caused by the natural chemical compounds and anthropogenic compounds, already being demonstrated that a great part of them change the endocrine control over reproduction at different species. The issue studied by our team is concerned with the histological changes that appear within liver, kidney and gonadal development at the zebra fish (Danio rerio, exposed to octylphenol from 21-115 days, and within 21-75 days of life. In order to achieve the histological preparations, for each period under study, fishes were divided into three groups of 30 individuals, namely: Lot 1 - Control, respectively lots 2 and 3, at which the administrated octylphenol concentrations were of 60 ?g L-1, respectively 100 ?g L-1. Fishes of the six groups were raised in 30-liters aquariums (30 fish / aquarium. Fragments of liver, kidney and gonads were processed histologically, colored with the Mallory thrichromic staining method and examined with the optical microscope. Histopathological study revealed changes in the three organs, namely this fine granulation hepatocytes, peritubular edema and vascular ectasia in renal parenchyma and their differentiation in the gonads to sex predominantly female, issues that demonstrate the estrogenic effect of the octylphenol. Those microscopical aspects observed in the kidney and liver of the specimens exposed to action of octhylphenol, suggest that the octhlyphenol is bind to the estrogenic receptors on the membrane of hepatic cells, inducing vitellogenin synthesis.

  5. RELAXATION OF MAGNETIC FIELD RELATIVE TO PLASMA DENSITY REVEALED FROM MICROWAVE ZEBRA PATTERNS ASSOCIATED WITH SOLAR FLARES

    Energy Technology Data Exchange (ETDEWEB)

    Yu Sijie; Yan Yihua; Tan Baolin, E-mail: sjyu@nao.cas.cn, E-mail: yyh@nao.cas.cn, E-mail: bltan@nao.cas.cn [Key Laboratory of Solar Activity, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China)

    2012-12-20

    It is generally considered that the emission of microwave zebra pattern (ZP) structures requires high density and high temperature, which is similar to the situation of the flaring region where primary energy is released. Therefore, a parameter analysis of ZPs may reveal the physical conditions of the flaring source region. This work investigates the variations of 74 microwave ZP structures observed by the Chinese Solar Broadband Radio Spectrometer (SBRS/Huairou) at 2.6-3.8 GHz in nine solar flares, and we find that the ratio between the plasma density scale height L{sub N} and the magnetic field scale height L{sub B} in emission sources displays a tendency to decrease during the flaring processes. The ratio L{sub N} /L{sub B} is about 3-5 before the maximum of flares. It decreases to about 2 after the maximum. The detailed analysis of three typical X-class flares implies that the variation of L{sub N} /L{sub B} during the flaring process is most likely due to topological changes of the magnetic field in the flaring source region, and the stepwise decrease of L{sub N} /L{sub B} possibly reflects the magnetic field relaxation relative to the plasma density when the flaring energy is released. This result may also constrain solar flare modeling to some extent.

  6. Relaxation of magnetic field relative to plasma density revealed from microwave zebra patterns associated with solar flares

    CERN Document Server

    Yu, Sijie; Tan, Baolin

    2012-01-01

    It is generally considered that the emission of microwave zebra pattern (ZP) structures requires high density and high temperatures, which is similar to the situation of the flaring region where primary energy releases. Therefore, the parameters analysis of ZPs may reveal the physical conditions of the flaring source region. This work investigates the variations of 74 microwave ZP structures observed by Chinese Solar Broadband Radio Spectrometer (SBRS/Huairou) at 2.6-3.8 GHz in 9 solar flares, and found that the ratio between the plasma density scale height LN and the magnetic field scale height LB in emission source displays a tendency of decrease during the flaring processes. The ratio LN/LB is about 3-5 before the maximum of flares. It decreases to about 2 after the maximum. The detailed analysis of three typical X-class flares implied that the variation of LN/LB during the flaring process is most likely due to the topological changes of the magnetic field in the flaring source region, and the step-wise de...

  7. RELAXATION OF MAGNETIC FIELD RELATIVE TO PLASMA DENSITY REVEALED FROM MICROWAVE ZEBRA PATTERNS ASSOCIATED WITH SOLAR FLARES

    International Nuclear Information System (INIS)

    It is generally considered that the emission of microwave zebra pattern (ZP) structures requires high density and high temperature, which is similar to the situation of the flaring region where primary energy is released. Therefore, a parameter analysis of ZPs may reveal the physical conditions of the flaring source region. This work investigates the variations of 74 microwave ZP structures observed by the Chinese Solar Broadband Radio Spectrometer (SBRS/Huairou) at 2.6-3.8 GHz in nine solar flares, and we find that the ratio between the plasma density scale height LN and the magnetic field scale height LB in emission sources displays a tendency to decrease during the flaring processes. The ratio LN /LB is about 3-5 before the maximum of flares. It decreases to about 2 after the maximum. The detailed analysis of three typical X-class flares implies that the variation of LN /LB during the flaring process is most likely due to topological changes of the magnetic field in the flaring source region, and the stepwise decrease of LN /LB possibly reflects the magnetic field relaxation relative to the plasma density when the flaring energy is released. This result may also constrain solar flare modeling to some extent.

  8. Masculinisation of the Zebra Finch Song System: Roles of Oestradiol and the Z-chromosome Gene Tubulin-Specific Chaperone Protein A.

    Science.gov (United States)

    Beach, L Q; Wade, J

    2015-05-01

    Robust sex differences in brain and behaviour exist in zebra finches. Only males sing, and forebrain song control regions are more developed in males. The factors driving these differences are not clear, although numerous experiments have shown that oestradiol (E2 ) administered to female hatchlings partially masculinises brain and behaviour. Recent studies suggest that an increased expression of Z-chromosome genes in males (ZZ; females: ZW) might also play a role. The Z-gene tubulin-specific chaperone A (TBCA) exhibits increased expression in the lateral magnocellular nucleus of the anterior nidopallium (LMAN) of juvenile males compared to females; TBCA+ cells project to the robust nucleus of the arcopallium (RA). In the present study, we investigated the role of TBCA and tested hypotheses with respect to the interactive or additive effects of E2 and TBCA. We first examined whether E2 in hatchling zebra finches modulates TBCA expression in the LMAN. It affected neither the mRNA, nor protein in either sex. We then unilaterally delivered TBCA small interfering (si)RNA to the LMAN of developing females treated with E2 or vehicle and males treated with the aromatase inhibitor, fadrozole, or its control. In both sexes, decreasing TBCA in LMAN reduced RA cell number, cell size and volume. It also decreased LMAN volume in females. Fadrozole in males increased LMAN volume and RA cell size. TBCA siRNA delivered to the LMAN also decreased the projection from this brain region to the RA, as indicated by anterograde tract tracing. The results suggest that TBCA is involved in masculinising the song system. However, because no interactions between the siRNA and hormone manipulations were detected, TBCA does not appear to modulate effects of E2 in the zebra finch song circuit. PMID:25702708

  9. Compact hohlraum configuration with parallel planar-wire-array x-ray sources at the 1.7-MA Zebra generator.

    Science.gov (United States)

    Kantsyrev, V L; Chuvatin, A S; Rudakov, L I; Velikovich, A L; Shrestha, I K; Esaulov, A A; Safronova, A S; Shlyaptseva, V V; Osborne, G C; Astanovitsky, A L; Weller, M E; Stafford, A; Schultz, K A; Cooper, M C; Cuneo, M E; Jones, B; Vesey, R A

    2014-12-01

    A compact Z-pinch x-ray hohlraum design with parallel-driven x-ray sources is experimentally demonstrated in a configuration with a central target and tailored shine shields at a 1.7-MA Zebra generator. Driving in parallel two magnetically decoupled compact double-planar-wire Z pinches has demonstrated the generation of synchronized x-ray bursts that correlated well in time with x-ray emission from a central reemission target. Good agreement between simulated and measured hohlraum radiation temperature of the central target is shown. The advantages of compact hohlraum design applications for multi-MA facilities are discussed. PMID:25615200

  10. Compact hohlraum configuration with parallel planar-wire-array x-ray sources at the 1.7-MA Zebra generator

    Science.gov (United States)

    Kantsyrev, V. L.; Chuvatin, A. S.; Rudakov, L. I.; Velikovich, A. L.; Shrestha, I. K.; Esaulov, A. A.; Safronova, A. S.; Shlyaptseva, V. V.; Osborne, G. C.; Astanovitsky, A. L.; Weller, M. E.; Stafford, A.; Schultz, K. A.; Cooper, M. C.; Cuneo, M. E.; Jones, B.; Vesey, R. A.

    2014-12-01

    A compact Z-pinch x-ray hohlraum design with parallel-driven x-ray sources is experimentally demonstrated in a configuration with a central target and tailored shine shields at a 1.7-MA Zebra generator. Driving in parallel two magnetically decoupled compact double-planar-wire Z pinches has demonstrated the generation of synchronized x-ray bursts that correlated well in time with x-ray emission from a central reemission target. Good agreement between simulated and measured hohlraum radiation temperature of the central target is shown. The advantages of compact hohlraum design applications for multi-MA facilities are discussed.

  11. Mutation of a novel virulence-related gene mltD in Vibrio anguillarum enhances lethality in zebra fish.

    Science.gov (United States)

    Xu, Zinan; Wang, Ying; Han, Yin; Chen, Jixiang; Zhang, Xiao-Hua

    2011-01-01

    Vibrio anguillarum, a halophilic Gram-negative bacterium, is the causative agent of vibriosis, which is a major problem for the aquaculture industry worldwide. Previously, a virulence-related gene fragment of V. anguillarum was obtained from a suppression subtractive hybridization (SSH) library. In this study, the complete gene sequence was obtained by long and accurate PCR (LA-PCR). After sequence analysis and homologous comparison, this new virulence-related gene was revealed to encode a putative membrane-bound lytic murein transglycosylase D (MltD), which consisted of 547 amino acids, and showed 34% identity to the MltD in Escherichia coli. An mltD mutant of pathogenic V. anguillarum CW-1 was constructed by homologous recombination. Production of extracellular gelatinase and protease of the mltD mutant decreased markedly compared with those of the wild-type strain, and the hemolytic activity was totally lost. Sodium chloride challenge and antibiotic sensitivity assay showed that the resistance of the mltD mutant to high concentrations of sodium chloride, and rocephin, fortun, cefobid, gentamicin, kanamycin and carbenicillin was enhanced. Most importantly, virulence of the mltD mutant was enhanced compared with that of the wild type when it was inoculated intraperitoneally into zebra fish; the LD?? of the wild type and the mutant was 3.92 × 10³ CFU and 1.01 × 10² CFU fish?¹, respectively. The mltD was cloned and overexpressed in E. coli, and the recombinant MltD protein showed hemolytic, phospholipase, gelatinase and diastase activities. This is the first report that MltD possibly has a virulence-related function. PMID:21070855

  12. Study of the biological effects of uranium exposure on zebra fish (D. rerio). Impact on life stages

    International Nuclear Information System (INIS)

    This work is part of an ongoing project (ENVIRHOM) started at IRSN in 2000, which consists in studying the environmental effects of radioactive substances at chronic low level of exposure. In this general frame, our aim was two fold: (i) to identify sensitivity of different critical life stages of zebra fish (fish of fresh water frequently used for tests standards in ecotoxicology) to uranium exposure and (ii) to evaluate underlying mechanisms. Experiments were conducted with eggs, larvae and genitors exposed to uranium at environmentally relevant concentrations (from 20 to 500 ?g/L) in order to study survival, hatching of eggs, growth of larvae and reproduction of genitors. Bio-markers of exposure (i.e. U bioaccumulation) and bio-markers of effects at molecular level (i.e. genotoxic effects, reproductive-toxicity) were also measured. Sensitivity of fish to uranium was dependent of the life stage of development with the early life stage being the most sensitive to U either directly or maternally exposed. It underlines the relevance of including pro-larval stages for toxicity assessments in fish. Moreover drastic effects of uranium on reproductive success and DNA damages in the germ cells foretell a strong impact on the population for low concentration of exposure (20 ?g/L). As it is increasingly recognized that population-level effects of toxic substances are more relevant in terms of ecological risk assessment, this study points out the need to include different life stages of organisms in eco-toxicological studies, especially the sensitive early stages. Moreover, it appears, through the comparative study of the radiological effects or by another isotope of the uranium of stronger radioactivity (233U or by an irradiation with 137Cs), that the effects of the uranium are due to its chemo-toxicity. (author)

  13. Characterization of uranium effects on the zebra fish Danio rerio. Stress mechanisms, neuro-toxicity and mitochondrial metabolism

    International Nuclear Information System (INIS)

    This research explored several biological effects of uranium (U) in zebra fish exposed to low waterborne uranium concentrations (20 and 100 microgram/L). In tissue specific study (brain, liver, skeletal muscles and gills) of transcriptional responses in 20 genes identified the nature of the potential U effects during 28 days of exposure followed by an 8-day depuration phase in connection with U bioaccumulation. Liver and gills accumulate high concentrations of U and the depuration is efficient contrary to the brain and muscles. U exposure induced a later response in liver (inflammatory process, apoptosis and detoxification) and gills (oxidative balance) and an early one in brain (neuronal response) and muscles (mitochondrial metabolism). Brain and muscles appear sensitive since defence mechanisms are inefficient above low concentrations. A further study on these two organs examined the function and protein content of the respiratory mitochondrial chain following U exposure. An inhibition of the respiratory control ratio for the lowest concentration, variation in the protein synthesis of the complex IV (induction of cytochrome c oxidase sub-unit I and IV) and histological damage (dilatation in brain and vacuolisation in muscles) were observed. Another study focused on the early effects on the brain and was accomplished through a large transcriptional analysis coupled with examinations of the olfactory bulb ultrastructure. A depression of genes encoding olfactory receptor or111-7 and or102-5 was observed as rapidly as 3 days post-exposure to the lowest concentration of U. These responses and histological injuries suggest that the olfactory system could be sensitive to U exposure. (author)

  14. No Trade-Offs between Lipid Stores and Structural Growth in Juvenile Zebra Finches Undergoing Nutritional Stress during Development *.

    Science.gov (United States)

    Kriengwatana, Buddhamas; MacDougall-Shackleton, Scott A

    2015-01-01

    Abstract Nutritional conditions during development can affect both structural growth and body fat deposition. Body size and body fat each have significant consequences for fitness, yet few studies have investigated how young birds balance resource allocation between structural growth and fat reserves. We raised zebra finches (Taeniopygia guttata) in consistently high- or low-food conditions until posthatch day 35 (PHD 35). From this age until PHD 62, half of the birds in each condition were switched to the other treatment, while the rest were maintained on the same conditions. Body mass, lean mass, body fat, and tarsus length were measured before (PHD 25) and after (PHD 55) nutritional independence. Precise measures of body composition were obtained noninvasively at both ages using quantitative magnetic resonance analysis. At PHD 25, birds in the high treatment had more body mass and lean mass than birds in the low treatment, but nutritional treatments did not affect body fat at this age. Unexpectedly, the strategic response of birds that experienced deteriorating food availability was to maintain body mass by increasing body fat and decreasing lean mass. Birds that experienced an improvement in food availability significantly increased body mass by increasing lean mass and not body fat. Birds maintained on a low diet throughout did not significantly increase body mass, lean mass, or body fat. Tarsus length was not affected by nutritional manipulations. These findings indicate that nutritional stress did not affect the relationship between skeletal growth and body fat deposition because lean mass, body fat, and tarsus length can be independently regulated at different developmental periods depending on nutritional conditions. PMID:25730275

  15. Correlates of male fitness in captive zebra finches - a comparison of methods to disentangle genetic and environmental effects

    Directory of Open Access Journals (Sweden)

    Bolund Elisabeth

    2011-11-01

    Full Text Available Abstract Backgound It is a common observation in evolutionary studies that larger, more ornamented or earlier breeding individuals have higher fitness, but that body size, ornamentation or breeding time does not change despite of sometimes substantial heritability for these traits. A possible explanation for this is that these traits do not causally affect fitness, but rather happen to be indirectly correlated with fitness via unmeasured non-heritable aspects of condition (e.g. undernourished offspring grow small and have low fitness as adults due to poor health. Whether this explanation applies to a specific case can be examined by decomposing the covariance between trait and fitness into its genetic and environmental components using pedigree-based animal models. We here examine different methods of doing this for a captive zebra finch population where male fitness was measured in communal aviaries in relation to three phenotypic traits (tarsus length, beak colour and song rate. Results Our case study illustrates how methods that regress fitness over breeding values for phenotypic traits yield biased estimates as well as anti-conservative standard errors. Hence, it is necessary to estimate the genetic and environmental covariances between trait and fitness directly from a bivariate model. This method, however, is very demanding in terms of sample sizes. In our study parameter estimates of selection gradients for tarsus were consistent with the hypothesis of environmentally induced bias (?A = 0.035 ± 0.25 (SE, ?E = 0.57 ? 0.28 (SE, yet this differences between genetic and environmental selection gradients falls short of statistical significance. Conclusions To examine the generality of the idea that phenotypic selection gradients for certain traits (like size are consistently upwardly biased by environmental covariance a meta-analysis across study systems will be needed.

  16. Pre and post-natal antigen exposure can program the stress axis of adult zebra finches: evidence for environment matching.

    Science.gov (United States)

    Merrill, Loren; Grindstaff, Jennifer L

    2015-03-01

    Both maternal exposure to stressors and exposure of offspring to stressors during early life can have lifelong effects on the physiology and behavior of offspring. Stress exposure can permanently shape an individual's phenotype by influencing the development of the hypothalamic-pituitary-adrenal (HPA) axis, which is responsible for the production and regulation of glucocorticoids such as corticosterone (CORT). In this study we used captive zebra finches (Taeniopygia guttata) to examine the effects of matching and mismatching maternal and early post-natal exposure to one of two types of antigens or a control on HPA axis reactivity in adult offspring. Prior to breeding, adult females were injected with lipopolysaccharide (LPS), keyhole limpet hemocyanin (KLH) or a control. Offspring of females in each of the three treatments were themselves exposed to LPS, KLH or a control injection at 5 and 28days post-hatch. When offspring were at least 18months of age, standardized capture and restraint stress tests were conducted to determine the impact of the treatments on adult stress responsiveness. We found significant interaction effects between maternal and offspring treatments on stress-induced CORT levels, and evidence in support of the environment matching hypothesis for KLH-treated birds, not LPS-treated birds. KLH-treated offspring of KLH-treated mothers exhibited reduced stress-induced CORT levels, whereas LPS-treated or control offspring of KLH-treated mothers exhibited elevated stress-induced CORT levels. Although the treatment effects on baseline CORT were non-significant, the overall pattern was similar to the effects observed on stress-induced CORT levels. Our results highlight the complex nature of HPA axis programming, and to our knowledge, provide the first evidence that a match or mismatch between pre and post-natal antigen exposure can have life-long consequences for HPA axis function. PMID:25535860

  17. 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.

  18. 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.

    2013-01-01

    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.

  19. Líneas cebra: Repercusión radiológica de la acción de los bifosfonatos en el esqueleto inmaduro / Zebra lines: Radiological repercussions of the action of bisphosphonates on the immature skeleton

    Scientific Electronic Library Online (English)

    I., Etxebarria-Foronda; L., Gorostiola-Vidaurrazaga.

    2013-03-01

    Full Text Available Los bifosfonatos son utilizados en el tratamiento de la osteogénesis imperfecta, observándose con ellos una reducción de las fracturas en estos pacientes. Sin embargo, el uso de dichos fármacos en el esqueleto inmaduro de estos pacientes da lugar a la formación de unas bandas lineales hiperdensas vi [...] sibles radiológicamente, llamadas líneas cebra o zebra lines. Presentamos el caso de un paciente con osteogénesis imperfecta que inició tratamiento con bifosfonatos a los 10 años de edad y que al cabo de 2 años ya mostraba dichas imágenes radiológicas. Abstract in english The bisphosphonates are used in the treatment of osteogenesis imperfecta, with a reduction in fractures in these patients observed with their use. However, the use of these drugs on the immature skeleton in these patients results in the formation of some radiologically visible hyperdense linear band [...] s called zebra lines. We present the case of a patient with osteogenesis perfecta who started treatment with bisphosphonates at 10 years of age and after 2 years already showed these radiological images.

  20. Activation of D1-like dopamine receptors increases the NMDA-induced gain modulation through a PKA-dependent pathway in the premotor nucleus of adult zebra finches.

    Science.gov (United States)

    Wang, Songhua; Liao, Congshu; Meng, Wei; Huang, Qingyao; Li, Dongfeng

    2015-03-01

    Interaction between dopamine (DA) and N-methyl-d-aspartate (NMDA) in the brain plays an important role in learning and memory. In the songbirds, the premotor robust nucleus of the arcopallium (RA) receives excitatory glutamatergic inputs from the high vocal center (HVC) and lateral magnocellular nucleus of the anterior nidopallium (LMAN), as well as dopaminergic inputs mostly from the periaqueductal gray (PAG) and ventral tegmental area (VTA). In zebra finch, DA potentiates the excitability of projection neurons in the RA through activation of D1-like dopamine receptors (D1 receptors). The relationship between D1 receptors and NMDA in the RA projection neurons is essentially unknown. Our previous work showed that NMDA can induce gain modulation in the RA projection neurons. Here, using the whole-cell current-clamp recording from brain slices of male zebra finches, we observed whether D1 receptors regulate the NMDA-induced gain modulation in the RA projection neurons. Our results showed that activation of D1 receptors further increased the slope (gain) of the firing frequency-injected current (f-I) relationship induced by NMDA in the RA projection neurons. Blocking D1 receptors had no effect on the NMDA-induced gain modulation in the RA projection neurons. The enhanced effects of D1 receptors agonists were blocked by protein kinase A (PKA) inhibitors. Our results suggest that activation of D1 receptors can increase the NMDA-induced gain modulation through a PKA-dependent pathway. PMID:25596438

  1. Learning to cope with degraded sounds: female zebra finches can improve their expertise in discriminating between male voices at long distances.

    Science.gov (United States)

    Mouterde, Solveig C; Elie, Julie E; Theunissen, Frédéric E; Mathevon, Nicolas

    2014-09-01

    Reliable transmission of acoustic information about individual identity is of critical importance for pair bond maintenance in numerous monogamous songbirds. However, information transfer can be impaired by environmental constraints such as external noise or propagation-induced degradation. Birds have been shown to use several adaptive strategies to deal with difficult signal transmission contexts. Specifically, a number of studies have suggested that vocal plasticity at the emitter's level allows birds to counteract the deleterious effects of sound degradation. Although the communication process involves both the emitter and the receiver, perceptual plasticity at the receiver's level has received little attention. Here, we explored the reliability of individual recognition by female zebra finches (Taeniopygia guttata), testing whether perceptual training can improve discrimination of degraded individual vocal signatures. We found that female zebra finches are proficient in discriminating between calls of individual males at long distances, and even more so when they can train themselves with increasingly degraded signals over time. In this latter context, females succeed in discriminating between males as far as 250 m. This result emphasizes that adaptation to adverse communication conditions may involve not only the emitter's vocal plasticity but also the receptor's decoding process through on-going learning. PMID:24948627

  2. Two-photon deep imaging through skin and skull of Zebra finches: preliminary studies for in-vivo brain metabolism monitoring

    Science.gov (United States)

    Abi-Haidar, D.; Olivier, T.; Mottin, S.; Vignal, C.; Mathevon, N.

    2007-02-01

    Zebra Finches are songbirds which constitute a model for neuro-ethologists to study the neuro-mechanisms of vocal recognition. For this purpose, in vivo and non invasive monitoring of brain activity is required during acoustical stimulation. MRI (Magnetic Resonance Imaging) or NIRS (Near InfraRed Spectroscopy) are suitable methods for these measurements, even though MRI is difficult to link quantitatively with neural activity and NIRS suffers from a poor resolution. In the particular case of songbirds (whose skin is thin and quite transparent and whose skull structure is hollow), two-photon microscopy enables a quite deep penetration in tissues and could be an alternative. We present here preliminary studies on the feasability of two-photon microscopy in these conditions. To do so, we chose to image hollow fibers, filled with Rhodamine B, through the skin of Zebra finches in order to evaluate the spatial resolution we may expect in future in vivo experiments. Moreover, we used the reflectance-mode confocal configuration to evaluate the exponential decrease of backreflected light in skin and in skull samples. Following this procedure recently proposed by S.L. Jacques and co-workers, we planned to determine the scattering coefficient ? s and the anisotropy g of these tissues and make a comparison between fixed and fresh skin and skull samples for future Monte Carlo simulations of the scattering in our particular multi-layered structure.

  3. Assessment of mercury and methylmercury pollution with zebra mussel (Dreissena polymorpha) in the Ebro River (NE Spain) impacted by industrial hazardous dumps.

    Science.gov (United States)

    Carrasco, Luis; Díez, Sergi; Soto, David X; Catalan, Jordi; Bayona, Josep M

    2008-12-15

    Large amounts of industrial waste containing high concentrations of mercury (up to 436 microg/g) are dumped in a reservoir adjacent to a chlor-alkali plant in Flix (Catalonia, Spain), on the lower Ebro River. In order to assess the spatial redistribution of mercury from the point source and its bioavailability to the aquatic food web, zebra mussels (Dreissena polymorpha) were collected at several sites. The highest total Hg (THg) and methylmercury (MeHg) concentrations ever reported for zebra mussels were found (THg: 0.02 to 0.81 microg/g ww; MeHg: 0.22 to 0.60 microg/g ww). At the most polluted site, close to the waste dump, the mean values were 20 times greater than the local background level. Concentrations decreased with increasing mussel size at all sites. The MeHg/THg ratio was ca. 60% (range: 50-80%). A comparison of similar size classes clearly indicated the hot spots of Hg bioavailability to the aquatic food web and downstream transport. PMID:18805569

  4. Early-developmental stress, repeatability, and canalization in a suite of physiological and behavioral traits in female zebra finches.

    Science.gov (United States)

    Careau, Vincent; Buttemer, William A; Buchanan, Katherine L

    2014-10-01

    Adaptive developmental plasticity allows individuals experiencing poor environmental conditions in early life to adjust their life-history strategy in order to prioritize short-term fitness benefits and maximize reproductive output in challenging environments. Much research has been conducted to test whether such adoption of a "faster" life-history strategy is accompanied by concordant changes in behavior and physiology, with mixed results. As research in this field has focused on comparison of mean-level responses of treatment groups, few studies include repeated measures of response variables and the effect that developmental stress may have on repeatability per se. We investigated how early-developmental stress affects the mean expression of (and repeatability in) a variety of behavioral and physiological traits in female zebra finches. We predicted that: (1) individuals subjected to nutritional restriction in the nestling phase would have higher feeding and activity rates, with associated increases in hematocrit and basal metabolic rates (BMRs), (2) nutritional restriction in early life would alter adults' stress-induced corticosterone level, and (3) developmental stress would, respectively, influence the amount of among-individual and within-individual variation in behavioral and physiological traits, hence affecting the repeatability of these traits. In comparison to control females, stressed females did not differ in activity rate or stress-induced corticosterone level, but they did have higher levels of feeding, hematocrit, and BMR. Among-individual variance and repeatability were generally higher in stressed females than in controls. Finally, we found that developmental dietary restriction significantly reduced the amount of within-individual variance both in activity rate in the novel environment and in stress-induced corticosterone level. Our results not only confirm previous findings on the effect of early-developmental stress on BMR, but also extend its effect to feeding rate and hematocrit, suggesting that developmental plasticity in these traits is ontogenetically linked. Early-developmental stress may disable particular genetic canalizing processes, which would release cryptic genetic variation and explain why repeatability and among-individual variance were generally higher in the stressed groups than in controls. For activity rate in the novel environment and with stress-induced corticosterone level, however, early-developmental stress significantly reduced within-individual variance, which may be a consequence of increased canalization of these traits at the micro-environmental level. PMID:24966164

  5. A newly discovered superoantero-orbital sinus connecting to the interaural canal may play a role in zebra finch hearing

    DEFF Research Database (Denmark)

    Jensen, Kenneth Kragh; Christensen-Dalsgaard, Jakob

    The middle ears of birds are acoustically connected through an air-filled pathway, the interaural canal (IAC), which allows sound to propagate internally from one ear to the other and considerably enhance the cues for directional hearing. The enhancement of the directional cues depends on the amplitude gain and time delay through IAC. Theoretically, different combinations of frequency dependent gains and delays produce very different directionalities of the ears but it is still uncertain how gain and delay can be shaped by evolution. We have discovered that a large forehead sinus superoanterior to the orbits (superoantero-orbital sinus, SAOS) connects to the IAC via a tube inferomedial to the orbits (IMT). SAOS has a very complex shape with connections through an arc over the eye to the bullae of each ear and also to two smaller lateral sinuses in front of each eye. The contribution of this structure to auditory sensitivity has not been studied previously. We hypothesized that the extra air volume could form a resonator influencing the gain and delay of IAC. We tested the hypothesis by measuring sound transmission through IAC of zebra finches before and after filling the SAOS with a silicone impression medium. Six out of seven individuals showed an effect of filling the SAOS or the IMT on directionality and overall auditory sensitivity. The SAOS therefore does seem to have an effect on gain and delay in the interaural canal as well as on auditory sensitivity. The effect, however, was complex and either significantly changed the gain by up to 10 dB in the frequency range below about 2-3 kHz and/or in a narrow band around 4-6 kHz. Although we verified the fillings by post-experimental dissection, it was difficult to determine exactly to what degree the different components were filled. Thus differential filling and/or blockage of the complex system may be the reason for complexity of the results. Future experiments aim for better control of the cavity filling.

  6. Condición fisiológica de Arca zebra por grupos de tallas y su asociación con variables ambientales, en el banco de Chacopata, estado Sucre / Physiological condition of Arca zebra by groups of sizes and its association with environmental variables, in the bank of Chacopata, Sucre state

    Scientific Electronic Library Online (English)

    María E, Lista Alfonzo; Carlos J, Velásquez; Antulio S, Prieto Arcas; Yelipza C, Longart Rojas.

    2014-03-01

    Full Text Available Se evaluó la condición fisiológica de A. zebra por grupos de tallas y su asociación con variables ambientales analizando el índice de condición (IC), para lo cual se realizaron salidas de campo al morro de Chacopata, desde junio 2008 hasta junio 2009. Se colectaron las muestras con una rastra de 120 [...] x 86 cm, a una profundidad aproximada de 8 m. Se seleccionaron al azar ejemplares de diferentes longitudes (Lt) distribuyéndolos en cuatro grupos de tallas: grupo I ( de 70,0 mm). A cada ejemplar, mensualmente se le determinó la biomasa seca de la gónada (Psg) y el peso total del organismo (Psorg) y, a partir de estos se obtuvo el IC. También se registraron mensualmente variables ambientales: temperatura, salinidad, oxígeno disuelto, seston total, orgánico e inorgánico y la clorofila a. Los resultados indicaron que el IC de los organismos del grupo I, se correlacionaron positivamente con la clorofila a y la salinidad; mientras, que los ejemplares de los grupos II, III y IV el IC mostró asociación positiva con la temperatura; indicando la influencia que ejercen las variables ambientales sobre la fisiología de A. zebra. La especie mostró una buena condición fisiológica en ejemplares > de 50,0 mm, siendo a partir de esta talla la recomendada para su explotación comercial y en los períodos: junio-septiembre y noviembre de cada año. Abstract in english The physiological condition of A. zebra by groups of sizes and its association with environmental variables were evaluated analysing the condition index (CI), for which there were field trips to the morro de Chacopata, from June 2008 to June 2009. The samples were collected with a drag of 120 x 86 c [...] m, to an approximate depth of 8 m. It is randomly selected samples of different lengths (Lt) distributed in four groups of sizes: group I ( 70.0 mm). Each samples, monthly was determined the dry biomass of the gonad (Psg) and the total weight of the body (Psorg) and, from these won the IC. Also there were monthly environmental variables: temperature, salinity, dissolved oxygen, seston total, organic and inorganic and chlorophyll a. The results indicated that the CI in the organisms of the group I, were positively correlated with the chlorophyll a and salinity; while, that samples of the groups II, III and IV the IC showed positive association with temperature; indicating the influence of environmental variables on the physiology of A. zebra. The species showed a good physiological condition in samples > of 50.0 mm, being from this size recommended for their commercial exploitation and in the periods: June, September and November of each year.

  7. Modeling of K-Shell Al and Mg and L-Shell Mo Radiation from Compact Cylindrical Wire Array Plasmas Produced on the 1 MA UNR Zebra Generator

    International Nuclear Information System (INIS)

    K-shell radiation of Al and Mg and L-shell radiation of Mo from implosions of compact cylindrical wire arrays (CCWA) on the 1 MA UNR Zebra generator was studied. Specifically, radiation from implosions of 3 and 6 mm CCWA with (16-24) Al-5052 (95% Al and 5% Mg) and Al-5052 (97.5% Al and 2.5% Mg) and Mo wires was analyzed using the full set of diagnostics: PCD and current signals, and X-ray pinhole images and spectra. Previously developed non-LTE models were applied to model spatially resolved time integrated as well as time-gated spatially integrated spectra from Al, Mg, and Mo plasmas. Derived electron temperature and density spatial gradients as well as percentage of radiating mass were studied and compared. In addition, the novel Wire Dynamics Model (WDM) was used to analyze the implosion dynamics of compact wire array loads.

  8. On the origin of zebra textures in Mississippi Valley-Type Pb-Zn Deposits with a special emphasis on the San Vicente Mine, Peru

    Science.gov (United States)

    Kelka, Ulrich; Koehn, Daniel

    2014-05-01

    Alternating dark and white bands are common features of ore hosting dolostones which are generally termed zebra textures. Worldwide these structures occur in ore deposits of the Mississippi Valley-Type (MVT). This type of deposit frequently develops in hydrothermal systems located in the flanks of foreland basins. In most MVT ore deposits it is possible to distinguish between different stages which occur during the formation of the zebra textures and the precipitation of the ore-minerals (mostly Sphalerite and Galena). As the dark and white bands consist nearly completely of dolomite, despite the colour, the only clearly recognisable difference is the grain size. Today there are several theories which try to explain the formation of this kind of structure, for example by dissolution-precipitation (FONTBONTé et al., 1993) or by displacive vein growth (MERINO et al., 2006). Based on these theories and additional analytical findings, we want to develop a numerical model to study the banding and mineralisation. This model should include all processes from dolomitization, to the development of the zebra textures and finally the precipitation of Sphalerite and Galena. Using optical microscope and SEM, we found, that there are also differences in the shapes of the grain boundaries of the fine grained dark (lobate) and coarse grained white bands (polygonal). Furthermore, there is a large number of second-phase particles, namely apatite, iron oxides and organic matter, present in the dark bands. Often these particles are lined up at the grain boundaries. These insights lead to the hypothesis that the grain growth in the dark bands is influenced by obstacles that reduce the growth rate and therefore lead to a bifurcation of this rate in the system. For the modelling the microdynamic simulation software ELLE is used to perform a 2D-simulation at the scale of a thin section. This simulation uses a boundary-model coupled with a lattice-particle-code (BONS et al. 2001). The grain boundaries move according to a rate law based on dissolution-precipitation processes as a function of differences in surface energy. Layered distributions of particle densities are initially set as a background. With this simple simulation of grain growth influenced by particle distributions we show, that this process is able to develop structural patterns that are very similar to those present in the natural samples from the San Vicente Mine in Peru. References BONS P D, KOEHN D, and JESSELL W (2008) Microdynamic Simulation. Springer-Verlag Berlin Heidelberg FONTBONTé L (1993) Self-organization fabrics in carbonate-hosted ore deposits: the example of diagenetic crystallization rhythmites (DCRs), In: Current research in geology applied to ore deposits. Proceedings of the Second Biennial SGA Meeting, Granada, Spain, p. 11 -14 MERINO E, CANALS A, and FLECHTER R C (2006) Genesis of self-organized zebra textures in burial dolomites: Displacive veins, induced stress, and dolomitization. Geologica Acta, Vol. 4 No. 3, p. 383-393

  9. Effects of the bioaccumulative polybrominated diphenyl ether flame retardant congener BDE-47 on growth, development, and reproductive success in zebra finches.

    Science.gov (United States)

    Currier, Heidi A; Letcher, Robert J; Williams, Tony D; Elliott, John E

    2015-02-01

    This study investigated the effects of the polybrominated diphenyl ether congener, 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) on the growth and development, and subsequent breeding success of exposed zebra finches (Taeniopygia guttata). Using oral dosing procedures and treatments adjusted by weight, we treated newly hatched chicks daily for the first 20-days-post-hatch (dph) with varying treatments of BDE-47 (0, 5, 50, and 500 ng/g bw/day). Weight and tarsal measurements were monitored from hatch to 90 dph, but no differences were observed between treatment groups at any age. Treated females that reached sexual maturity were mated with untreated males; however, again no treatment effects were observed on breeding success. Analysis of tissue samples at 21 dph did indicate that debromination of BDE-47 had occurred resulting in BDE-28 and BDE-17 metabolites. PMID:25283367

  10. Genomic organization and molecular phylogenies of the beta (? 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 (? keratins. The molecular phylogeny of these keratins is important to understanding the evolutionary origin of these appendages, especially feathers. Knowing that the crocodilian ?-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 ?-keratins, but to study their molecular evolution in archosaurians. Results The subfamilies (claw, feather, feather-like, and scale of ?-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 ?-keratin clades are expressed. Conclusions Similarity in the overall genomic organization of ?-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 ?-keratin gene cluster. As morphological diversification of epidermal appendages occurred and the ?-keratin multigene family expanded, novel ?-keratin genes were selected for novel functions within appendages such as feathers.

  11. 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)

    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 ium 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

  12. Functional genomic analysis and neuroanatomical localization of miR-2954, a song-responsive sex-linked microRNA in the zebra finch

    Science.gov (United States)

    Lin, Ya-Chi; Balakrishnan, Christopher N.; Clayton, David F.

    2014-01-01

    Natural experience can cause complex changes in gene expression in brain centers for cognition and perception, but the mechanisms that link perceptual experience and neurogenomic regulation are not understood. MicroRNAs (miRNAs or miRs) have the potential to regulate large gene expression networks, and a previous study showed that a natural perceptual stimulus (hearing the sound of birdsong in zebra finches) triggers rapid changes in expression of several miRs in the auditory forebrain. Here we evaluate the functional potential of one of these, miR-2954, which has been found so far only in birds and is encoded on the Z sex chromosome. Using fluorescence in situ hybridization and immunohistochemistry, we show that miR-2954 is present in subsets of cells in the sexually dimorphic brain regions involved in song production and perception, with notable enrichment in cell nuclei. We then probe its regulatory function by inhibiting its expression in a zebra finch cell line (G266) and measuring effects on endogenous gene expression using Illumina RNA sequencing (RNA-seq). Approximately 1000 different mRNAs change in expression by 1.5-fold or more (adjusted p < 0.01), with increases in some but not all of the targets that had been predicted by Targetscan. The population of RNAs that increase after miR-2954 inhibition is notably enriched for ones involved in the MAP Kinase (MAPK) pathway, whereas the decreasing population is dominated by genes involved in ribosomes and mitochondrial function. Since song stimulation itself triggers a decrease in miR-2954 expression followed by a delayed decrease in genes encoding ribosomal and mitochondrial functions, we suggest that miR-2954 may mediate some of the neurogenomic effects of song habituation. PMID:25565940

  13. miR-9 and miR-140-5p Target FoxP2 and Are Regulated as a Function of the Social Context of Singing Behavior in Zebra Finches

    OpenAIRE

    Shi, Zhimin; Luo, Guanzheng; Fu, Lijuan; Fang, Zhide; Wang, Xiujie; Li, Xiaoching

    2013-01-01

    Mutations in the FOXP2 gene cause speech and language impairments, accompanied by structural and functional abnormalities in brain regions underlying speech-related sensory-motor processing, including the striatum and cerebellum. The sequence and expression patterns of FOXP2 are highly conserved among higher vertebrates. In the zebra finch brain, FoxP2 is expressed in Area X, a striatal nucleus required for vocal learning, and reduced FoxP2 expression impairs dendritic development and vocal l...

  14. Descripción y variación mensual de las etapas reproductivas de la pepitona Arca zebra (Swainson, 1833) en el banco de Chacopata, península de Araya, estado Sucre, Venezuela / Description and monthly variation in reproductive stages of the clam Arca zebra (Swainson, 1833) in the Chacopata bank, Araya peninsula, Sucre state, Venezuela

    Scientific Electronic Library Online (English)

    María, Lista; Antulio, Prieto; Carlos, Velásquez; César, Lodeiros; Vanessa, Acosta; Yelipza, Longart; Gilma, Hernández.

    2011-03-01

    Full Text Available Se estudió la variación mensual (12 meses) de las etapas reproductivas e histológicas en ejemplares adultos de Arca zebra, recolectados en el banco natural de Chacopata, estado Sucre, Venezuela. Las características histológicas del tejido gonadal se describieron en función de los siguientes estadios [...] reproductivos: reposo (0), inicio de la madurez (I), madurez total (II), desove parcial (III), desove total y degeneración (IV). No se encontraron diferencias significativas en la proporción total de sexos, aunque este parámetro difirió significativamente de una relación 1M:1H en algunos meses. La especie presenta asincronía en la maduración de los folículos, sin embargo, el análisis cuantitativo reveló que los estadios II y III estuvieron presentes durante todo el período de muestreo. Se observaron los cinco estadios de maduración gonadal en hembras, pero solamente los estadios I al III en machos. Las frecuencias de los estadios se relacionaron con las variaciones significativas que presentaron los promedios mensuales del diámetro de los folículos y del lumen en ambos sexos. El diámetro promedio de los óvulos maduros fue de 6,00 ± 0,11 ?m, presentando su máima proporció en el estadio II. El incremento del estadio II, observado desde julio hasta septiembre 2002, se correlacionó con aumentos de temperatura, mientras que el incremento del estadio III coincidió con disminuciones de temperatura observados desde octubre de 2002 hasta enero de 2003. Tanto la salinidad como la concentración de clorofila a mostraron escasa variación durante el estudio, indicando que no son factores limitantes durante el proceso reproductivo de la especie. Se concluye que las alteraciones en la temperatura del agua parecen ser el principal factor asociado a las variaciones en el ciclo reproductivo en A. zebra. Abstract in english Monthly variation (12 months) in reproductive stages and histology in adult specimens of Arca zebra harvested from natural bed of Chacopata, Sucre state, Venezuela were studiedied. The histological characteristics of gonadal tissue were described according to their reproductive stages: resting (0), [...] onset of maturity (I), total maturity (II), partial spawning (III), total spawning and degeneration (IV). There were no significant differences in the total proportion of sexes, although there was significant differences in the 1M:1F relation in some months. The species presents asynchrony in the maturation of the follicles, however, quantitative analysis shows that while stages II and III were present throughout the sampling period. Males were observed in stages 0 and IV, but in females. Changes in the frequency of the stages were associated with significant variations presented the monthly mean diameter of follicles and the lumen in both sexes, were always higher in females. The average diameter of mature eggs was 5,88 ± 0,11 ?m, showing its highest proportion in stage II. The increase in stage II observed from July to September 2002 was correlated with increases in temperature, while the increase of stage III coincides with the observed temperature decreases from October 2002 to January 2003. Salinity showed little variation, and the chlorophyll remained constant during the study, indicating that there is a limiting factor, so it is suggested that temperature is the main factor associated with reproductive changes in A. zebra.

  15. Evaluation of an immunofiltration assay that detects immunoglobulin M antibodies against the ZEBRA protein for the diagnosis of Epstein-Barr virus infectious mononucleosis in immunocompetent patients.

    Science.gov (United States)

    Bravo, Dayana; Muñoz-Cobo, Beatriz; Costa, Elisa; Clari, M Angeles; Tormo, Nuria; Navarro, David

    2009-06-01

    The performance of an immunofiltration assay (IMFA) that detects immunoglobulin M (IgM) antibodies to the Epstein-Barr virus (EBV) ZEBRA (BamHI Z EBV replication activator) protein was evaluated for the diagnosis of EBV infectious mononucleosis (IM) in immunocompetent patients. The test panel consisted of 47 sera displaying an EBV-specific antibody profile compatible with an acute primary EBV infection from patients with clinical and biological features of EBV IM, 20 sera from healthy individuals either with a past EBV infection or who were EBV seronegative, 20 sera displaying an equivocal EBV antibody pattern (viral capsid antigen IgG positive [VCA IgG+], VCA IgM+, and EBV nuclear antigen-1 IgG+), and 15 sera obtained from patients with a mononucleosis-like syndrome owing to cytomegalovirus, human herpesvirus 6, or parvovirus B19. Overall, the sensitivity and the specificity of the assay were found to be 92.5%, and 97.3%, respectively. The sensitivity of the assay for the diagnosis of heterophile antibody-negative EBV IM was 86.2%. The IMFA is rapid, easy to perform, and, thus, suitable for point-of-care testing, and it may be used as a first-line test for the diagnosis of acute EBV IM in immunocompetent patients. PMID:19403783

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1981-10-20

    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.

  17. 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)

    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 evidences of AChE neuropil staining. This evidence suggesting that sexually dimorphic projections to or within Area X are cholinergic or cholinoceptive

  18. First analysis of radiative properties of moderate-atomic-number planar wire arrays on Zebra at UNR at higher current of 1.7 MA.

    Energy Technology Data Exchange (ETDEWEB)

    Keim, S. F. (University of Nevada, Reno, NV); Chuvatin, Alexander S. (Ecole Polytechnique, Palaiseau, France); Osborne, Glenn C. (University of Nevada, Reno, NV); Esaulov, Andrey A. (University of Nevada, Reno, NV); Presura, R. (University of Nevada, Reno, NV); Shrestha, I. (University of Nevada, Reno, NV); Kantsyrev, Victor Leonidovich (University of Nevada, Reno, NV); Shlyaptseva, V. (University of Nevada, Reno, NV); Coverdale, Christine Anne; Williamson, K. M. (University of Nevada, Reno, NV); Ouart, Nicholas D. (University of Nevada, Reno, NV); Astanovitsky, A. L. (University of Nevada, Reno, NV); Weller, M. E. (University of Nevada, Reno, NV); Safronova, Alla S. (University of Nevada, Reno, NV); LeGalloudec, B. (University of Nevada, Reno, NV)

    2010-11-01

    The analysis of implosions of Cu and Ag planar wire array (PWA) loads recently performed at the enhanced 1.7 MA Zebra generator at UNR is presented. Experiments were performed with a Load Current Multiplier with a 1cm anode-cathode gap (twice shorter than in a standard 1 MA mode). A full diagnostic set included more than ten different beam-lines with the major focus on time-gated and time-integrated x-ray imaging and spectra, total radiation yields, and fast, filtered x-ray detector data. In particular, the experimental results for a double PWA load consisting of twelve 10 {micro}m Cu wires in each row (total mass M {approx} 175 {micro}g) and a much heavier single PWA load consisting of ten 30 {micro}m Ag wires (M {approx} 750 {micro}g) were analyzed using a set of theoretical codes. The effects of both a decreased a-c gap and an increased current on radiative properties of these loads are discussed.

  19. First Analysis of Radiative Properties of Moderate-atomic-number Planar Wire Arrays on Zebra at UNR at Higher Current of 1.7 MA*

    Science.gov (United States)

    Safronova, A. S.; Kantsyrev, V. L.; Esaulov, A. A.; Astanovitskiy, A.; Legalloudec, B.; Presura, R.; Shrestha, I.; Williamson, K. M.; Shlyaptseva, V.; Weller, M. E.; Ouart, N. D.; Keim, S. F.; Osborne, G. C.; Chuvatin, A. S.; Coverdale, C. A.

    2010-11-01

    The analysis of implosions of Cu and Ag planar wire array (PWA) loads recently performed at the enhanced 1.7 MA Zebra generator at UNR is presented. Experiments were performed with a Load Current Multiplier with a 1cm anode-cathode gap (twice shorter than in a standard 1 MA mode). A full diagnostic set included more than ten different beam-lines with the major focus on time-gated and time-integrated x-ray imaging and spectra, total radiation yields, and fast, filtered x-ray detector data. In particular, the experimental results for a double PWA load consisting of twelve 10?m Cu wires in each row (total mass M ˜ 175 ?g) and a much heavier single PWA load consisting of ten 30?m Ag wires (M ˜ 750 ?g) were analyzed using a set of theoretical codes. The effects of both a decreased a-c gap and an increased current on radiative properties of these loads are discussed. * This work was supported by NNSA/DOE Coop. Agr. DE-FC52-06NA27588, 27586, and 27616. Sandia is a multi-program laboratory operated by Sandia Co., a LMC, for the US DOE under Contract DE-AC04-94AL85000.

  20. Activation of AMP-activated protein kinase in response to temperature elevation shows seasonal variation in the zebra mussel, Dreissena polymorpha.

    Science.gov (United States)

    Jost, Jennifer A; Keshwani, Sarah S; Abou-Hanna, Jacob J

    2015-04-01

    Global climate change is affecting ectothermic species, and a variety of studies are needed on thermal tolerances, especially from cellular and physiological perspectives. This study utilized AMP-activated protein kinase (AMPK), a key regulator of cellular energy levels, to examine the effects of high water temperatures on zebra mussel (Dreissena polymorpha) physiology. During heating, AMPK activity increased as water temperature increased to a point, and maximum AMPK activity was detected at high, but sublethal, water temperatures. This pattern varied with season, suggesting that cellular mechanisms of seasonal thermal acclimatization affect basic metabolic processes during sublethal heat stress. There was a greater seasonal variation in the water temperature at which maximum AMPK activity was measured than in lethal water temperature. Furthermore, baseline AMPK activity varied significantly across seasons, most likely reflecting altered metabolic states during times of growth and reproduction. In addition, when summer-collected mussels were lab-acclimated to winter and spring water temperatures, patterns of heat stress mirrored those of field-collected animals. These data suggest that water temperature is the main driver of the seasonal variation in physiology. This study concluded that AMPK activity, which reflects changes in energy supply and demand during heat stress, can serve as a sensitive and early indicator of temperature stress in mussels. PMID:25498351

  1. Influence of body size on Cu bioaccumulation in zebra mussels Dreissena polymorpha exposed to different sources of particle-associated Cu

    Energy Technology Data Exchange (ETDEWEB)

    Zhong, Huan, E-mail: huanzhong1982@hotmail.com [Environmental and Resource Studies Program, Trent University, Peterborough, Ontario (Canada); Nanjing University, School of Environment, State Key Laboratory of Pollution Control and Resource Reuse, Nanjing, Jiangsu Province (China); Kraemer, Lisa; Evans, Douglas [Environmental and Resource Studies Program, Trent University, Peterborough, Ontario (Canada)

    2013-10-15

    Highlights: • Mussels exposed to algal/sediment-Cu have different size-related Cu accumulation. • Size-related Cu accumulation in mussels could be more dependant on algal-Cu uptake. • Importance of algal/sediment-Cu to Cu bioaccumulation varies with mussel body size. • Cu sources (algae and sediments) should be considered in “mussel watch” programs. • Cu stable isotope offers many advantages in Cu bioaccumulation studies. -- Abstract: Size of organisms is critical in controlling metal bioavailability and bioaccumulation, while mechanisms of size-related metal bioaccumulation are not fully understood. To investigate the influences of different sources of particle-associated Cu on body size-related Cu bioavailability and bioaccumulation, zebra mussels (Dreissena polymorpha) of different sizes were exposed to stable Cu isotope ({sup 65}Cu) spiked algae (Chlorella vulgaris) or sediments in the laboratory and the Cu tissue concentration-size relationships were compared with that in unexposed mussels. Copper tissue concentrations decreased with mussel size (tissue or shell dry weight) in both unexposed and algal-exposed mussels with similar decreasing patterns, but were independent of size in sediment-exposed mussels. Furthermore, the relative contribution of Cu uptake from algae (65–91%) to Cu bioaccumulation is always higher than that from sediments (9–35%), possibly due to the higher bioavailability of algal-Cu. Therefore, the size-related ingestion of algae could be more important in influencing the size-related variations in Cu bioaccumulation. However, the relative contribution of sediment-Cu to Cu bioaccumulation increased with body size and thus sediment ingestion may also affect the size-related Cu variations in larger mussels (tissue weight >7.5 mg). This study highlights the importance of considering exposure pathways in normalization of metal concentration variation when using bivalves as biomonitors.

  2. Towards a validation of a cellular biomarker suite in native and transplanted zebra mussels: A 2-year integrative field study of seasonal and pollution-induced variations

    International Nuclear Information System (INIS)

    Two of the questions raised in the validation process of biomarkers are their relevance in the identification and discrimination of environmental perturbations, and the influence of seasonal factors on these biological endpoints. Determining the advantages and restrictions associated with the use of native or transplanted animals and comparing their responses is also needed. To obtain this information, a 2-year integrative field study was conducted in the vicinity of a nuclear power plant in northeastern France. A station was located in the reservoir receiving the cooling waters of the plant, and two other sites were studied 2 km upstream and 5 km downstream from the reservoir's discharge in the Moselle river. Elevated temperatures, copper contamination and a 1.4-fold-concentration factor of dissolved salts affected water quality of the reservoir. Native and transplanted zebra mussels (Dreissena polymorpha) were collected monthly and their digestive glands were processed for histochemical determinations of the lysosomal and peroxisomal systems and of the lipofuscin and neutral lipid contents. The responses were quantified using automated image analysis and stereology. Apart from neutral lipid contents, there were no systematic seasonal patterns in mussel populations or from 1 year to another. Principal Component Analyses showed a general higher discrimination potential of biological responses in transplanted organisms compared to native ones. They also pointed out the to native ones. They also pointed out the relationships between the cellular and physiological markers and abiotic factors. The present multiple biomarker integrative approach in transplanted D. polymorpha brings promising elements in their validation process as relevant biomonitoring tools

  3. Comparison of acute toxicity of process chemicals used in the oil refinery industry, tested with the diatom Chaetoceros gracilis, the flagellate Isochrysis galbana, and the zebra fish, Brachydanio rerio

    International Nuclear Information System (INIS)

    Chemicals under the trade names Nalco 537-DA, Nalco 625, Nalco 7607, Nalco 5165, Ivamin, and technical monoethanolamine are used extensively in the oil refinery industry. Aquatic toxicity tests were conducted using zebra fish fry (Brachydanio rerio) and the unicellular algae Isochrysis galbana (a flagellate) and Chaetoceros gracilis (a diatom). Inhibition of cell division, chlorophyll content, and 14CO2 uptake in the algae were sensitive end points. The effective concentrations (EC50s) of growth inhibition were 0.1 mg/L (Ivamin; I. galbana), 0.8 mg/L (Nalco 7607; I. galbana), 6 mg/L (Nalco 625; I. galbana), 10 mg/L (Nalco 5165; C. gracilis), and 15 mg/L (Nalco 537-DA; C. gracilis). The lethal concentrations (LC50s) (96 h) toward zebra fish fry was 1 mg/L for Nalco 7607, 6.5 mg/L for Nalco 537-DA, 7.1 mg/L for Nalco 625, and 20 mg/L for Ivamin 803. Monoethanolamine had an LC50 higher than 5,000 mg/L. Nalco 5165 was not tested on fish fry. The heartbeat frequency of fish embryos was reduced by 2.5 mg/L Nalco 537-DA, but this was an insensitive end point for the other chemicals

  4. Recalibrating Equus evolution using the genome sequence of an early Middle Pleistocene horse

    DEFF Research Database (Denmark)

    Orlando, Ludovic Antoine Alexandre; Ginolhac, Aurélien

    2013-01-01

    The rich fossil record of equids has made them a model for evolutionary processes. Here we present a 1.12-times coverage draft genome from a horse bone recovered from permafrost dated to approximately 560-780 thousand years before present (kyr bp). Our data represent the oldest full genome sequence determined so far by almost an order of magnitude. For comparison, we sequenced the genome of a Late Pleistocene horse (43?kyr bp), and modern genomes of five domestic horse breeds (Equus ferus caballus), a Przewalski's horse (E. f. przewalskii) and a donkey (E. asinus). Our analyses suggest that the Equus lineage giving rise to all contemporary horses, zebras and donkeys originated 4.0-4.5?million years before present (Myr bp), twice the conventionally accepted time to the most recent common ancestor of the genus Equus. We also find that horse population size fluctuated multiple times over the past 2?Myr, particularly during periods of severe climatic changes. We estimate that the Przewalski's and domestic horse populations diverged 38-72?kyr bp, and find no evidence of recent admixture between the domestic horse breeds and the Przewalski's horse investigated. This supports the contention that Przewalski's horses represent the last surviving wild horse population. We find similar levels of genetic variation among Przewalski's and domestic populations, indicating that the former are genetically viable and worthy of conservation efforts. We also find evidence for continuous selection on the immune system and olfaction throughout horse evolution. Finally, we identify 29 genomic regions among horse breeds that deviate from neutrality and show low levels of genetic variation compared to the Przewalski's horse. Such regions could correspond to loci selected early during domestication.

  5. Recalibrating Equus evolution using the genome sequence of an early Middle Pleistocene horse.

    DEFF Research Database (Denmark)

    Orlando, Ludovic Antoine Alexandre; Ginolhac, Aurélien

    2013-01-01

    The rich fossil record of equids has made them a model for evolutionary processes. Here we present a 1.12-times coverage draft genome from a horse bone recovered from permafrost dated to approximately 560-780 thousand years before present (kyr bp). Our data represent the oldest full genome sequence determined so far by almost an order of magnitude. For comparison, we sequenced the genome of a Late Pleistocene horse (43 kyr bp), and modern genomes of five domestic horse breeds (Equus ferus caballus), a Przewalski's horse (E. f. przewalskii) and a donkey (E. asinus). Our analyses suggest that the Equus lineage giving rise to all contemporary horses, zebras and donkeys originated 4.0-4.5 million years before present (Myr bp), twice the conventionally accepted time to the most recent common ancestor of the genus Equus. We also find that horse population size fluctuated multiple times over the past 2 Myr, particularly during periods of severe climatic changes. We estimate that the Przewalski's and domestic horse populations diverged 38-72 kyr bp, and find no evidence of recent admixture between the domestic horse breeds and the Przewalski's horse investigated. This supports the contention that Przewalski's horses represent the last surviving wild horse population. We find similar levels of genetic variation among Przewalski's and domestic populations, indicating that the former are genetically viable and worthy of conservation efforts. We also find evidence for continuous selection on the immune system and olfaction throughout horse evolution. Finally, we identify 29 genomic regions among horse breeds that deviate from neutrality and show low levels of genetic variation compared to the Przewalski's horse. Such regions could correspond to loci selected early during domestication.

  6. Geochemical constraints for coexisting CO"2 gas hydrate and calcite: implications for sheet cracks, stromatactis, zebra and tepee-like structures [rapid communication

    Science.gov (United States)

    DiFilippo, Erica L.; Hammond, Douglas E.; Corsetti, Frank A.

    2003-08-01

    The Ordovician Meiklejohn Peak mud-mound in western Nevada contains sedimentary structures (e.g., stromatactis and "zebra-rock") that resemble features found in modern methane hydrate deposits. However, the ?13C of the mud-mound carbonates (-1 to 1‰ PDB) does not suggest interaction with ?13C-depleted methane. Consequently, Krause (Sedimentary Geology 145 (2001) 189) proposed that the Meiklejohn structures might have been produced by the formation and dissociation of CO 2 gas hydrate rather than methane gas hydrate. Structures in Neoproterozoic cap carbonates, sheet cracks and tepee-like structures have also been suggested to represent gas hydrate interaction with carbonate sediments (Geology 29 (2001) 443), but, similarly, ?13C values do not suggest direct interaction with methane. The objective of this contribution is to see if the presence of CO 2 gas hydrate is plausible for either setting. To test the feasibility of CO 2 gas hydrate involvement in the formation of these structures, necessary concentrations of TCO 2 were calculated based on required phase equilibria using the quadruple points Q1 (-1.73 °C, 10.2 atm) and Q2 (10.2 °C, 44.5 atm) from the phase diagram for CO 2 gas hydrate (Miller, S.L., 1974. The Nature and Occurrence of Clathrate Hydrates. In: Kaplan, I.R. (Ed.), Natural Gases in Marine Sediments. Plenum, New York, NY, pp. 151-178). A limit for Ca +2 was established based on the lack of evidence for gypsum formation in this environment and the assumption that sulfate was up to 100% of its present oceanic value; the calculated TCO 2 concentration, however, is relatively insensitive to the concentration of SO 4-2 used. The lowest permissible value of pCO 2 and TCO 2 were found at Q1, where TCO 2 must be at least 300 times the present value. These conditions are implausible for the formation of the Meiklejohn Peak mud-mound. Although some models for Neoproterozoic "Snowball Earth" require highly elevated atmospheric CO 2, these models predict pCO 2 that is still too low to permit the formation of CO 2 gas hydrates in carbonate sediments. In addition, if the required conditions could be achieved during "Snowball Earth", one would expect to find the associated structures only at the base of the section, while they are commonly observed meters to tens of meters above the base. Therefore, we conclude that it is unlikely these structures were produced by the formation and dissociation of CO 2 gas hydrate.

  7. Poly(N-isopropylacrylamide)-coated thermo-responsive nanoparticles for controlled delivery of sulfonated Zn-phthalocyanine in Chinese hamster ovary cells in vitro and zebra fish in vivo

    International Nuclear Information System (INIS)

    Poly(N-isopropylacrylamide) (PNIPAM)-coated Fe3O4 - SiO2 - CdTe multifunctional nanoparticles with photoluminescent (PL), thermosensitive and magnetic properties, were investigated as carriers to deliver water-soluble, fluorescent sulfonated Zn-phthalocyanine (ZnPcS), a photosensitizing drug for photodynamic therapy of cancer, in Chinese hamster ovary (CHO) cells in vitro and zebra fish in vivo. PNIPAM is a well-known thermo-responsive polymer with a volume phase transition temperature. This property allows it to be swollen in water at temperatures lower than 32-34 deg. C to take up ZnPcS and shrunken to expel the drug at higher temperatures. Since the PL band of CdTe quantum dots (QDs) as indicators for the nanoparticles is at 585 nm and the emission band of ZnPcS is at 680 nm, it is possible to study the temperature-dependent release of ZnPcS from the nanoparticles by fluorescence measurements. ZnPcS was embedded in the PNIPAM of the nanoparticles at 25 deg. C in phosphate buffered saline (PBS) solution and released at 37 deg. C, measured with a spectrophotometer. When CHO cells had been incubated with the ZnPcS-loaded nanoparticles at 27 deg. C, a similar intracellular localization pattern of CdTe QDs and ZnPcS was seen by multichannel measurements in confocal laser scanning microscopy (CLSM), but a diffuse pattern of only ZnPcS fluorescence was detected in the cytoplasm of the cells at 37 deg. C, indicating a release of ZnPcS from eg. C, indicating a release of ZnPcS from the nanoparticles. Similar results were also found in the intestinal tract of zebra fish in vivo after intake of the nanoparticles. Since the nanoparticles contain magnetic (Fe3O4) material, the nanoparticles could also be manipulated to change their location in the intestinal tract of the zebra fish with an external magnetic field gradient of 300 G mm-1. The results presented suggest that such multifunctional nanoparticles may have combined potential for temperature-dependent drug delivery, QD photodetection and magnetic manipulation in diagnosis and therapy of diseases

  8. Elementos traza detectados por plasma inductivamente acoplado (ICP) en pepitonas, Arca zebra (Mollusca, Arcidae) de dos localidades costeras del estado Sucre, Venezuela / Trace elements detected by Inductively Coupled Plasma (ICP) in Turkey wing, Arca zebra (Mollusca, Arcidae) from two coastal locations of Sucre State, Venezuela

    Scientific Electronic Library Online (English)

    Vilma, Lanza; Ildemaro, Martínez; Osmicar, Vallenilla; Julia, Márquez; Arquímedes, González; Jesús, Gamboa; José, Alió.

    2011-09-01

    Full Text Available Los metales pesados juegan un papel importante en la dinámica de los procesos químicos y ambientales en las zonas costeras. Estos provienen de aportes naturales y antropogénicos y pueden ser bioacumulados en organismos acuáticos, en los que se encuentran como elementos traza, y tienen potenciales ef [...] ectos tóxicos a quienes los consuman, principalmente al hombre como último eslabón de la cadena alimenticia. La gravedad del daño depende del grado y el tiempo de exposición a dichos elementos. Se determinó la concentración de metales pesados (Mg, Cu, Mn, Mo, Ni y Fe) por Plasma Inductivamente Acoplado (ICP) en la pepitona, Arca zebra (Mollusca, Bivalvia, Arcidae), provenientes de las inmediaciones de Caimancito y Chacopata (municipio Cruz Salmerón Acosta, estado Sucre, Venezuela). En Caimancito, las mayores concentraciones de casi todos los metales se detectaron en septiembre, a excepción del Mg que fue observada en febrero. En Chacopata, las concentraciones más elevadas se observaron en el mes de octubre (Mg, Mn y Ni), septiembre (Cu), diciembre (Fe) y en enero (Mo). No se encontraron diferencias significativas entre las localidades, mientras que existen diferencias significativas entre meses. Al momento no existen normas o regulaciones venezolanas que establezcan límites máximos de concentración de los metales analizados en moluscos bivalvos procesados o frescos, que permitan establecer comparaciones con los resultados obtenidos. Sin embargo, en base a normas internacionales, las concentraciones medidas de metales pesados en pepitonas no rebasaron los límites permitidos para consumo humano. Abstract in english Heavy metals play an important role in the dynamics of chemical and environmental processes in the coastal zones. They originate from natural and anthropogenic sources and can be bioaccumulated in aquatic organisms, where they are found as trace elements, and have potential toxic effects to those wh [...] o consume them, mainly to humans as the last link in the food chain. The severity of damage depends on the degree and time of exposure to these elements. The concentration of heavy metals (Mg, Cu, Mn, Mo, Ni and Fe) was estimated by Inductivelly Coupled Plasma (ICP) in the Turkey wing, Arca zebra (Mollusca, Bivalvia, Arcidae), from the vicinity to Caimancito and Chacopata (Municipality Cruz Salmerón Acosta, Sucre state, Venezuela). In Caimancito, higher concentrations of almost all metals were detected in September, except for Mg which was registered in February. In Chacopata, the highest concentrations were observed in October (Mg, Mn and Ni), September (Cu), December (Fe) and January (Mo). No significant differences were found between localities, while there were significant differences among months. At present there are not Venezuelan norms or regulations establishing the maximum concentration limits for the analyzed heavy metals in fresh or processed bivalve mollusks, which may enable comparisons with the obtained results. However, based upon international norms, the measured concentrations of heavy metals in Turkey wing apparently do not represent a threat for human consumption.

  9. Concentrations of 17 elements in the zebra mussel (Dreissena polymorpha), in different tissues of perch (Perca fluviatilis), and in perch intestinal parasites (Acanthocephalus lucii) from the subalpine lake Mondsee, Austria

    Energy Technology Data Exchange (ETDEWEB)

    Sures, B.; Steiner, W.; Rydlo, M.; Taraschewski, H.

    1999-11-01

    Concentrations of the elements Al, Ag, Ba, ca, Cd, Co, Cr, cu, Fe, Ga, Mg, Mn, Ni, Pb, Sr, Tl, and Zn were analyzed by inductively coupled plasma mass spectrometry in the acanthocephalan Acanthocephalus lucii (Mueller); in its host, Perca fluviatilis (L.), and in the soft tissue of the zebra mussel, Dreissena polymorpha (Pallas). All animals were collected from the same sampling site in a subalpine lake, Mondsee, in Austria. Most of the elements were found at significantly higher concentrations in the acanthocephalan than in different tissues (muscle, liver, and intestinal wall) of its perch host. Only Co was concentrated in the liver of perch to a level that was significantly higher than that found in the parasite. Most of the analyzed elements were also present at significantly higher concentrations in A. lucii than in D. polymorpha. Barium and Cr were the only elements recorded at higher concentrations in the mussel compared with the acanthocephalan. Thus, when comparing the accumulation of elements, the acanthocephalans appear to be even more suitable than the zebra mussels in terms of their use in the detection of metal contamination within aquatic biotopes. Spearman correlation analysis revealed that the concentrations of several elements within the parasites decreased with increasing infrapopulation. Furthermore, the levels of some elements in the perch liver were negatively correlated with the weight of A. lucii in the intestine. Thus, it emerged that not only is there competition for elements between acanthocephalans inside the gut but there is also competition for these elements between the host and the parasites. The elevated element concentrations demonstrated here in the parasitic worm A. lucii provide support for further investigations of these common helminthes and of their accumulation properties.

  10. Zebra fish emerging from egg

    Science.gov (United States)

    Katie Hale (CSUF; Biological Sciences)

    2007-06-08

    The egg is broken down by microorganisms and young fry are able to push through the egg material. The fry is the second stage of the life cycle. The fry is born with a yolk-sac that contains nutrients for the fry to continue to grow until maturity into a juvenile.

  11. The zebras come to CERN

    CERN Multimedia

    Laëtitia Pedroso

    2010-01-01

    From 23 to 26 November CERN played host to an unusual group of visitors, who arrived in a red-and-white striped camper. On the tenth anniversary of "Les Zèbres”, a children’s broadcast on Swiss radio, the show’s makers invited 8th and 9th grade pupils from Swiss schools to conduct a live broadcast from CERN.   Students in the cryogenic hall: cryolab. Popular Franco-Swiss host Jean-Marc Richard brought Les Zèbres to the Laboratory with a live broadcast. The idea was to let the children themselves host the broadcast. Accompanied by their physics teachers, pupils from junior secondary schools in Golette, Colombières and Drize were given the opportunity to spend half a day at CERN. Each day, one class came to find out about a particular aspect of the Laboratory and then conduct a live broadcast with Jean-Marc Richard from 12:10 to 12:30. The young people, aged 13 to 15, had a chance to explore the Universe of Particles exhibitio...

  12. 77 FR 26779 - Endangered Species; Receipt of Applications for Permit

    Science.gov (United States)

    2012-05-07

    ...africanus) Asian wild ass (Equus hemionus) Przewalski's horse (Equus przewalskii) Grevy's zebra (Equus grevyi) Eld's...lechwe (Kobus leche) scimitar-horned oryx (Oryx dammah) Arabian oryx (Oryx leucoryx) dama gazelle (Nanger dama)...

  13. Induction of heat shock proteins (hsp70) in the zebra mussel (Dreissena polymorpha) following exposure to platinum group metals (platinum, palladium and rhodium): Comparison with lead and cadmium exposures

    Energy Technology Data Exchange (ETDEWEB)

    Singer, Christoph [Zoologisches Institut I-Oekologie, Universitaet Karlsruhe, Geb. 07.01, Kornblumenstrasse 13, D-76131 Karlsruhe (Germany); Zimmermann, Sonja [Zoologisches Institut I-Oekologie, Universitaet Karlsruhe, Geb. 07.01, Kornblumenstrasse 13, D-76131 Karlsruhe (Germany); Sures, Bernd [Zoologisches Institut I-Oekologie, Universitaet Karlsruhe, Geb. 07.01, Kornblumenstrasse 13, D-76131 Karlsruhe (Germany)]. E-mail: dc11@rz.uni-karlsruhe.de

    2005-10-05

    An increasing number of papers concentrate on the availability and uptake of platinum group elements (PGE) by different organisms. These metals are discharged into the environment from different anthropogenic sources, such as automobile catalytic converters, hospitals and other medical institutions. As the effects of these precious metals on organisms remain unclear, the induction of heat shock proteins (hsp70) in zebra mussels (Dreissena polymorpha) following exposure to soluble salts of platinum, palladium and rhodium was compared with the hsp70 induction in mussels following exposure to cadmium and lead. Mussels were sampled weekly during a period of 10 weeks and analyzed for their metal concentration and their hsp70 level. Highest metal uptake was found for Cd, followed by Pt, Pb and Pd. Rh demonstrated the lowest uptake rate. A clear time-dependent increase of hsp70 levels occurred in all exposed mussels. Concentrations of hsp70 started to rise between days 18 and 25, except for the Pt-exposed group, where the initial increase was between days 25 and 32. All groups reached maximal hsp70 concentrations at day 39. Subsequently, hsp70 levels decreased to initial levels for the remaining exposure period. Threshold metal levels for the hsp70 induction varied among the metals and increased in the order: Rh < Pd {<=} Pb < Pt < Cd. Highest hsp70 values were found for mussels exposed to Pd, with a 25-fold higher level than in the controls, followed by Pt- and Rh-exposed mussels, which showed a 19-fold increase. The hsp70 levels of the mussels exposed to Cd and Pb were much lower, showing 6- and 12-fold higher values than the control, respectively. The clear induction of hsp70 due to exposure to Pt, Pd and Rh gives evidence for strong cellular effects of these metals, especially, when compared with lead and cadmium. Among the metals tested, Pd seems to have the highest potential as inducer for hsp70 production due to its low threshold level in combination with the strongest effect.

  14. Induction of heat shock proteins (hsp70) in the zebra mussel (Dreissena polymorpha) following exposure to platinum group metals (platinum, palladium and rhodium): Comparison with lead and cadmium exposures

    International Nuclear Information System (INIS)

    An increasing number of papers concentrate on the availability and uptake of platinum group elements (PGE) by different organisms. These metals are discharged into the environment from different anthropogenic sources, such as automobile catalytic converters, hospitals and other medical institutions. As the effects of these precious metals on organisms remain unclear, the induction of heat shock proteins (hsp70) in zebra mussels (Dreissena polymorpha) following exposure to soluble salts of platinum, palladium and rhodium was compared with the hsp70 induction in mussels following exposure to cadmium and lead. Mussels were sampled weekly during a period of 10 weeks and analyzed for their metal concentration and their hsp70 level. Highest metal uptake was found for Cd, followed by Pt, Pb and Pd. Rh demonstrated the lowest uptake rate. A clear time-dependent increase of hsp70 levels occurred in all exposed mussels. Concentrations of hsp70 started to rise between days 18 and 25, except for the Pt-exposed group, where the initial increase was between days 25 and 32. All groups reached maximal hsp70 concentrations at day 39. Subsequently, hsp70 levels decreased to initial levels for the remaining exposure period. Threshold metal levels for the hsp70 induction varied among the metals and increased in the order: Rh < Pd ? Pb < Pt < Cd. Highest hsp70 values were found for mussels exposed to Pd, with a 25-fold higher level than in the controls, followed by Pt- and Rh-exposed mutrols, followed by Pt- and Rh-exposed mussels, which showed a 19-fold increase. The hsp70 levels of the mussels exposed to Cd and Pb were much lower, showing 6- and 12-fold higher values than the control, respectively. The clear induction of hsp70 due to exposure to Pt, Pd and Rh gives evidence for strong cellular effects of these metals, especially, when compared with lead and cadmium. Among the metals tested, Pd seems to have the highest potential as inducer for hsp70 production due to its low threshold level in combination with the strongest effect

  15. Toxicidade de aminoácidos em peixe-zebra

    OpenAIRE

    Vieira, Pedro Emanuel Ferreira Dos Reis

    2011-01-01

    As proteínas são sintetizadas através do mecanismo de tradução e são constituídas por aminoácidos. Além de serem as unidades básicas das proteínas, os aminoácidos também desempenham outras funções importantes na célula, tais como sinalização ou regulação do crescimento celular. No entanto, em excesso, os aminoácidos podem ser tóxicos, embora o mecanismo de toxicidade não esteja claro. Neste estudo, usámos o peixezebra como modelo vertebrado para avali...

  16. Adaptive molecular evolution of the Major Histocompatibility Complex genes, DRA and DQA, in the genus Equus

    Directory of Open Access Journals (Sweden)

    Getz Wayne M

    2011-05-01

    Full Text Available Abstract Background Major Histocompatibility Complex (MHC genes are central to vertebrate immune response and are believed to be under balancing selection by pathogens. This hypothesis has been supported by observations of extremely high polymorphism, elevated nonsynonymous to synonymous base pair substitution rates and trans-species polymorphisms at these loci. In equids, the organization and variability of this gene family has been described, however the full extent of diversity and selection is unknown. As selection is not expected to act uniformly on a functional gene, maximum likelihood codon-based models of selection that allow heterogeneity in selection across codon positions can be valuable for examining MHC gene evolution and the molecular basis for species adaptations. Results We investigated the evolution of two class II MHC genes of the Equine Lymphocyte Antigen (ELA, DRA and DQA, in the genus Equus with the addition of novel alleles identified in plains zebra (E. quagga, formerly E. burchelli. We found that both genes exhibited a high degree of polymorphism and inter-specific sharing of allele lineages. To our knowledge, DRA allelic diversity was discovered to be higher than has ever been observed in vertebrates. Evidence was also found to support a duplication of the DQA locus. Selection analyses, evaluated in terms of relative rates of nonsynonymous to synonymous mutations (dN/dS averaged over the gene region, indicated that the majority of codon sites were conserved and under purifying selection (dN dS. However, the most likely evolutionary codon models allowed for variable rates of selection across codon sites at both loci and, at the DQA, supported the hypothesis of positive selection acting on specific sites. Conclusions Observations of elevated genetic diversity and trans-species polymorphisms supported the conclusion that balancing selection may be acting on these loci. Furthermore, at the DQA, positive selection was occurring at antigen binding sites, suggesting that a few selected residues may play a significant role in equid immune function. Future studies in natural equid populations will be valuable for understanding the functional significance of the uniquely diverse DRA locus and for elucidating the mechanism maintaining diversity at these MHC loci.

  17. Macrorhabdus ornithogaster in ostrich, rhea, canary, zebra finch, free range chicken, turkey, guinea-fowl, columbina pigeon, toucan, chuckar partridge and experimental infection in chicken, japanese quail and mice / Macrorhabdus ornithogaster em avestruzes, ema, canário, mandarim, galinha, peru, galinha da Angola, pombo doméstico, rolinha, tucano, perdiz de chuckar e infecção experimental em galinha, codorna e camundongo

    Scientific Electronic Library Online (English)

    N.R.S., Martins; A.C., Horta; A.M., Siqueira; S.Q., Lopes; J.S., Resende; M.A., Jorge; R.A., Assis; N.E., Martins; A.A., Fernandes; P.R., Barrios; T.J.R., Costa; L.M.C., Guimarães.

    2006-06-01

    Full Text Available Desde 2000, diversos casos de infecção e doença por Macrorhabdus ornithogaster (megabacteria) foram diagnosticados no Setor de Doenças das Aves (Escola de Veterinária da UFMG). A doença clínica foi caracterizada por emagrecimento, prostração, perda do apetite, caquexia e morte, em curso crônico, emb [...] ora com forma mais aguda em canários e periquitos. O microrganismo grande, em forma de bastão, visível a partir de 100 aumentos sem e com coloração, pode também ser detectado em aves de aspecto clínico normal, principalmente galinhas, perus, codornas e pombos. Em emas (Rhea), avestruzes (Struthio camelus), canários, mandarins, galinhas da Angola (Numida meleagris) e periquitos Australianos (Melopsittacus undulatus), a severidade da doença foi sempre maior, ocasionando até 100% de mortalidade em alguns plantéis. Na maioria das espécies a doença foi detectada em aves com endo e/ou ectoparasitismo. O cultivo de M. ornithogaster foi obtido em meio sólido (ágar para fungos patogênicos) e subcultivado em meio líquido (thioglicolato), do proventriculo de galinha, galinha da Angola, perdiz de chuckar e canário. O resultado mais surpreendente na microscopia de M. ornithogaster foi a presença de motilidade, detectada tanto de cultivos in vitro quanto de preparações úmidas de in vivo. Diferenças nos aspectos das colônias foram notadas entre os isolados. Infecções experimentais em galinha (SPF) e codorna japonesa permitiram a detecção do organismo nos proventrículos das aves de aspecto normal. Nas codornas, à necropsia notaram-se hemorragias hepáticas. A infecção experimental em camundongos via intraperitoneal resultou em 100% de mortalidade, também com lesões hepáticas. Aspectos do cultivo, a importância da doença, as espécies de aves susceptíveis e seu papel na epidemiologia são discutidos. Abstract in english Since 2000, Macrorhabdus ornithogaster "megabacteriosis" has been diagnosed in the avian diseases laboratory in a diversity of avian species and varied spectrum of disease. The disease in some species (chickens, turkeys, guinea fowls) was clinically characterized by emaciation, prostration, loss of [...] appetite, cachexia and death, with a typically chronic course. A more acute disease was observed in finches (canary-Serinus and zebra-Taeniopygia) and budgerigars (Melopsittacus undulatus). The large rod shaped organism, visible from 100 times magnification, with and without staining, could be detected in sick and also in reasonably normal individuals of some species, such as chickens, turkeys, quails and pigeons. In rheas (Rhea americana), ostriches (Struthio camelus), canaries, zebra-finches, guinea-fowl (Numida meleagris) and budgerigars. The disease was severe, causing to up to 100% mortality. The infection could be detected in some species along with other infectious or disease problems, such as endoparasites (helminths, coccidia) and ectoparasitism (order Mallophaga or/and order Acarina). The cultivation of M. ornithogaster was successfully achieved in solid and liquid media, originated from chickens (four isolates), guinea fowl (1 isolate), chuckar partridge (1 isolate) and canary (1 isolate). A very interesting finding at microscopy was motility of M. ornithogaster, as detected both in cultures obtained on agar for pathogenic fungi and passaged into thioglycolate broth, as well as on samples observed in wet preparations from in vivo. Differences in colony aspects were noted among the isolates. Experimental infections were attempted in chicken and japanese quail, using a chicken isolate, allowing the detection of the organism in the proventriculus and liver in apparently normal birds. One chicken isolate was injected intraperitoneally in Balb/c mice and resulted in 100% mortality.

  18. Macrorhabdus ornithogaster in ostrich, rhea, canary, zebra finch, free range chicken, turkey, guinea-fowl, columbina pigeon, toucan, chuckar partridge and experimental infection in chicken, japanese quail and mice Macrorhabdus ornithogaster em avestruzes, ema, canário, mandarim, galinha, peru, galinha da Angola, pombo doméstico, rolinha, tucano, perdiz de chuckar e infecção experimental em galinha, codorna e camundongo

    Directory of Open Access Journals (Sweden)

    N.R.S. Martins

    2006-06-01

    Full Text Available Since 2000, Macrorhabdus ornithogaster "megabacteriosis" has been diagnosed in the avian diseases laboratory in a diversity of avian species and varied spectrum of disease. The disease in some species (chickens, turkeys, guinea fowls was clinically characterized by emaciation, prostration, loss of appetite, cachexia and death, with a typically chronic course. A more acute disease was observed in finches (canary-Serinus and zebra-Taeniopygia and budgerigars (Melopsittacus undulatus. The large rod shaped organism, visible from 100 times magnification, with and without staining, could be detected in sick and also in reasonably normal individuals of some species, such as chickens, turkeys, quails and pigeons. In rheas (Rhea americana, ostriches (Struthio camelus, canaries, zebra-finches, guinea-fowl (Numida meleagris and budgerigars. The disease was severe, causing to up to 100% mortality. The infection could be detected in some species along with other infectious or disease problems, such as endoparasites (helminths, coccidia and ectoparasitism (order Mallophaga or/and order Acarina. The cultivation of M. ornithogaster was successfully achieved in solid and liquid media, originated from chickens (four isolates, guinea fowl (1 isolate, chuckar partridge (1 isolate and canary (1 isolate. A very interesting finding at microscopy was motility of M. ornithogaster, as detected both in cultures obtained on agar for pathogenic fungi and passaged into thioglycolate broth, as well as on samples observed in wet preparations from in vivo. Differences in colony aspects were noted among the isolates. Experimental infections were attempted in chicken and japanese quail, using a chicken isolate, allowing the detection of the organism in the proventriculus and liver in apparently normal birds. One chicken isolate was injected intraperitoneally in Balb/c mice and resulted in 100% mortality.Desde 2000, diversos casos de infecção e doença por Macrorhabdus ornithogaster (megabacteria foram diagnosticados no Setor de Doenças das Aves (Escola de Veterinária da UFMG. A doença clínica foi caracterizada por emagrecimento, prostração, perda do apetite, caquexia e morte, em curso crônico, embora com forma mais aguda em canários e periquitos. O microrganismo grande, em forma de bastão, visível a partir de 100 aumentos sem e com coloração, pode também ser detectado em aves de aspecto clínico normal, principalmente galinhas, perus, codornas e pombos. Em emas (Rhea, avestruzes (Struthio camelus, canários, mandarins, galinhas da Angola (Numida meleagris e periquitos Australianos (Melopsittacus undulatus, a severidade da doença foi sempre maior, ocasionando até 100% de mortalidade em alguns plantéis. Na maioria das espécies a doença foi detectada em aves com endo e/ou ectoparasitismo. O cultivo de M. ornithogaster foi obtido em meio sólido (ágar para fungos patogênicos e subcultivado em meio líquido (thioglicolato, do proventriculo de galinha, galinha da Angola, perdiz de chuckar e canário. O resultado mais surpreendente na microscopia de M. ornithogaster foi a presença de motilidade, detectada tanto de cultivos in vitro quanto de preparações úmidas de in vivo. Diferenças nos aspectos das colônias foram notadas entre os isolados. Infecções experimentais em galinha (SPF e codorna japonesa permitiram a detecção do organismo nos proventrículos das aves de aspecto normal. Nas codornas, à necropsia notaram-se hemorragias hepáticas. A infecção experimental em camundongos via intraperitoneal resultou em 100% de mortalidade, também com lesões hepáticas. Aspectos do cultivo, a importância da doença, as espécies de aves susceptíveis e seu papel na epidemiologia são discutidos.

  19. Leishmaniose tegumentar em uma mula (Equus caballus x equus asinus) em área endêmica no Estado do Rio de Janeiro Cutaneous leishmaniasis in a mule (Equus caballus x Equus asinus) in a endemic area of the state of Rio de Janeiro

    OpenAIRE

    Cruz Manuel Aguilar; Rangel, Elizabeth F.

    1986-01-01

    É relatado o encontro de infecção por parasitos do gênero Leishmania, em lesão cutânea de uma mula (Equus caballus x Equus asinus) procedente de uma localidade endêmica de leishmaniose tegumentar, no Estado do Rio de Janeiro.Leishmania parasites were found in a skin lesion of a mule (Equus caballus x Equus asinus) from a locality with endemic cutaneous leishmaniasis, in the state of Rio de Janeiro.

  20. „?????????????? ?????? ? ?????????? ????????? ? ????????? ? ????????????? ????????????. ??????? ??????”, zebra?a Aleksandra Archipowa, wydawca: ????? ?????????? ????????? ????????? ????, ?????? 2013, ss. 472.

    Directory of Open Access Journals (Sweden)

    Dorota Pazio-Wlaz?owska

    2014-12-01

    Full Text Available „Mifologicheskie modeli i ritual’noe povedenie v sovetskom i postsovetskom prostranstve: sbornik state?” Arkhipova, A. (Comp., Moskva: TSentr tipologii i semiotiki fol’klora RGGU 2013, pp. 472The volume under discussion, entitled ?????????????? ?????? ? ?????????? ????????? ? ????????? ? ????????????? ????????????, contains lectures that were delivered during a conference organized by the Centre for Typology and Semiotics of Folklore Studies of the Russian State University for the Humanities in September 2013. In this volume, based on rich source material, which has been shown from different perspectives, the following issues were discussed: visional transformation, celebrating of new rites, creating new rituals, magical practices and leaders’ images.

  1. O peixe zebra como uma ferramenta para avaliação de ecotoxicidade

    OpenAIRE

    Oliveira, Rhaul

    2009-01-01

    The zebrafish (Danio rerio) is a model vertebrate extensively used in scientific investigation worldwide. In the last decades, protocols and techniques have been developed in order to evaluate the effects of chemicals at different levels of biological organization of this species and to characterize the lethal and sublethal effects of pollutants. The main aim of this study was to assess the toxicity of different classes of chemicals to Danio rerio at lethal and sublethal levels...

  2. ORAL ESTROGEN MASCULINIZES FEMALE ZEBRA FINCH SONG SYSTEM. (R825294)

    Science.gov (United States)

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  3. Communicating about stress : modulation of vocalisations in the zebra finch

    OpenAIRE

    Perez, Emilie

    2013-01-01

    In social species, vocalisations convey information that participates in the maintenance and the survival of the group. While many studies were interested in stable information carried by vocal signals, like identity, fewer studies dealt with their potential role in informing about labile information such as the senders’ emotional state. Stress is a good candidate for the study of the expression of emotions in animals, as it is directly measurable by the plasma levels of glucocorticoïds. S...

  4. Chronic fatigue syndrome: identifying zebras amongst the horses

    Directory of Open Access Journals (Sweden)

    Wessely Simon

    2009-10-01

    Full Text Available Abstract There are currently no investigative tools or physical signs that can confirm or refute the presence of chronic fatigue syndrome (CFS. As a result, clinicians must decide how long to keep looking for alternative explanations for fatigue before settling on a diagnosis of CFS. Too little investigation risks serious or easily treatable causes of fatigue being overlooked, whilst too many increases the risk of iatrogenic harm and reduces the opportunity for early focused treatment. A paper by Jones et al published this month in BMC Medicine may help clinicians in deciding how to undertake such investigations. Their results suggest that if clinicians look for common psychiatric and medical conditions in those complaining of prolonged fatigue, the rate of detection will be higher than previously estimated. The most common co-morbid condition identified was depression, suggesting a simple mental state examination remains the most productive single investigation in any new person presenting with unexplained fatigue. Currently, most diagnostic criteria advice CFS should not be diagnosed when an active medical or psychiatric condition which may explain the fatigue is identified. We discuss a number of recent prospective studies that have provided valuable insights into the aetiology of chronic fatigue and describe a model for understanding chronic fatigue which may be equally relevant regardless of whether or not an apparent medical cause for fatigue can be identified. See the associated research paper by Jones et al: http://www.biomedcentral.com/1741-7015/7/57

  5. Sexual conflict reduces offspring fitness in zebra finches.

    Science.gov (United States)

    Royle, Nick J; Hartley, Ian R; Parker, Geoff A

    2002-04-18

    Parental care is often costly; hence, in sexually reproducing species where both male and female parents rear their offspring (biparental care), sexual conflict over parental investment can arise. Such conflict occurs because each care-giver would benefit from withholding parental investment for use with another partner, leading to a reduction in the amount of care given by one parent at the expense of the other. Here we report experiments to explore the prediction from theory that parents rearing offspring alone may provide greater parental investment than when rearing offspring together with a partner. We found that when the number of offspring per parent, and hence the potential workload, were kept constant, offspring received a greater per capita parental investment from single females than from both parents working together, and that males reared by single mothers were more sexually attractive as adults than their biparentally reared siblings. This difference between single- and two-parent families is due to a reduction in care provided by females when they care together with a male, rather than laziness by males or differences in the begging behaviour of chicks, supporting the claim that sexual conflict in biparental care can reduce the quality of offspring raised. PMID:11961554

  6. Chronic fatigue syndrome: identifying zebras amongst the horses

    OpenAIRE

    Wessely Simon; Harvey Samuel B

    2009-01-01

    Abstract There are currently no investigative tools or physical signs that can confirm or refute the presence of chronic fatigue syndrome (CFS). As a result, clinicians must decide how long to keep looking for alternative explanations for fatigue before settling on a diagnosis of CFS. Too little investigation risks serious or easily treatable causes of fatigue being overlooked, whilst too many increases the risk of iatrogenic harm and reduces the opportunity for early focused treatment. A pap...

  7. FindZebra: A search engine for rare diseases

    OpenAIRE

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

    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 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 ...

  8. Características morfológicas do funículo espermático do burro (Equus asinus x Equus caballus) / Morphological aspects of the spermatic cord in mules (Equus asinus x Equus caballus)

    Scientific Electronic Library Online (English)

    Roberto Pimenta de Pádua, FOZ FILHO; Antônio, FERNANDES FILHO; Vicente, BORELLI.

    Full Text Available Estudando 15 pares de funículos espermáticos de burros (Equus asinus x Equus caballus), observamos em 5 pares que seus componentes acham-se envolvidos por delgada cápsula de tecido conjuntivo denso, revestido por mesotélio. Sob esta cápsula e em estreita relação com ela encontra-se espessa camada de [...] musculatura lisa (músculo cremáster interno) que acompanha também o mesoducto deferente. A cápsula funicular e o músculo cremáster interno aparecem em alguns pontos levemente pregueados. Os componentes vásculo-nervosos estão envolvidos por tecido conjuntivo frouxo integrado predominantemente por fibras colágenas. A artéria testicular no funículo mostra trajeto sinuoso, túnica interna constituída por endotélio acompanhado de delicada camada de tecido conjuntivo e lâmina elástica limitante interna. Sua espessa túnica média é composta por fibras musculares lisas sustentadas por rede de fibras reticulares, e a túnica externa, por tecido conjuntivo que se confunde com o tecido conjuntivo intervascular. As veias testiculares aparecem em grande número, possuem túnica média formada por fibras elásticas e reticulares, com poucas fibras musculares e são desprovidas de válvulas, envolvem as artérias testiculares formando os plexos pampiniformes. O modelo do segmento da artéria testicular obtido com Neoprene látex 450 em 20 preparações, correspondentes a 10 pares de funículos espermáticos, apresentaram, respectivamente como comprimentos médio, máximo e mínimo, 58,2 cm, 81,0 cm e 44,0 cm à direita e 66,3 cm, 96,0 cm e 51,0 cm à esquerda. Abstract in english In a morphologic study of 15 spermatic cord pairs of male mules (Equus asinus x Equus caballus), histology showed in 5 pairs that its components are involved in a thin capsule of a dense connective tissue, covered by a mesothelium. Underneath the capsule, in a close relation, we identified the inter [...] nal cremaster muscle. This muscle goes with mesoductus. The funicular capsule and muscular tissue form a few small plicae. The funicular vessels (testicular artery and veins) are wrapped up in loose conjunctive tissue prevailing collagen fibers. The funicular part of the testicular artery is convoluted. It shows a thick tunica média vasorum supported by a net of reticular fibers; tunica intima vasorum is build up endothelium, thin connective tissue and a well defined internal elastic layer; tunica externa vasorum with the connective tissue becoming part of intervascular connective tissue. The testicular veins constituted a very elaborated close-meshed pampiniform plexus in which contortions of the artery are embedded. These veins have a medial tunic formed by elastic and reticular fibers, with a few muscular fibers without valves. The part of testicular artery model obtained with Neoprene latex 450 in 20 preparations, corresponding to 10 pairs of spermatic cords, have mean, maximum, and minimum lengths, respectively, of 58,2 cm, 81 cm, and 44 cm to the right side and 66,5 cm, 96 cm, and 51 cm to the left side.

  9. Trypanosoma brucei Infection in Asymptomatic Greater Kudus (Tragelaphus strepsiceros) on a Game Ranch in Zambia

    OpenAIRE

    Munang Andu, Hetron Mweemba; Siamudaala, Victor; Munyeme, Musso; Nambota, Andrew; Mutoloki, Stephen; Matandiko, Wigganson

    2010-01-01

    Trypomastogotes of Trypanosoma brucei were detected from 4 asymptomatic kudus (Tragelaphus strepsiceros) on a game ranch located approximately 45 km north east of Lusaka, Zambia. Blood smears examined from 14 wildlife species comprising of the impala (Aepyceros melampus), Kafue lechwe (kobus leche kafuensis), sable antelope (Hippotragus niger), tsessebe (Damaliscus lunatus), warthog (Phacochoerus aethiopicus), puku (Kobus vardoni), zebra (Equus burchelli), waterbuck (Kobus ellipsiprymnus), bu...

  10. Esteatosis en un burro (Equus asinus). Primer reporte en Colombia / Steatosis in donkey (Equus asinus). First report in Colombia

    Scientific Electronic Library Online (English)

    José, Cardona; Lázaro, Reza G.

    2793-27-01

    Full Text Available Se describe un caso de esteatosis en un burro (Equus asinus), castrado, de 15 años de edad, procedente del municipio de San Antero (Córdoba, Colombia), al cual se le detectó ligamento nucal engrosado, duro y doloroso, dando la impresión de un doble cuello y edemas subcutáneos indurados en pared cost [...] al, abdominal y pectoral. También presentó masas duras en la unión de músculos semimembranoso y semitendinoso. Por todo lo anterior, mostró dificultad para realizar movimientos coordinados del cuello, nuca y de traslado. Estos hallazgos obedecen principalmente a una deficiencia de selenio y vitamina E, sirviendo como parámetro diagnóstico para la identificación de esta enfermedad en equinos, por lo cual se determinó la actividad eritrocitica de la enzima glutatión peroxidada (GSH-Px), arrojando resultados muy bajos. Este cuadro es también conocido en equinos como enfermedad de la grasa amarilla o esteatitis, que produce degeneración del tejido adiposo, siendo reemplazado por tejido conectivo con depósitos de calcio. Puede estar asociada a miodegeneración nutricional o distrófica (enfermedad del músculo blanco). Es el primer reporte de esta enfermedad en burros (Equus asinus) que se hace en Colombia. Abstract in english A case of steatosis in a, 15 years old gelding donkey (Equus asinus), from the town of San Antero (Cordoba, Colombia) is described. the donkey, showed a hard and painful thickened nuchal ligament, giving the impression of a double neck tumors. It was also found an edema in the indurated subcutaneous [...] chest wall, abdomen and chest. It was also found hard lumps in the union of semimembranosus and semitendinosus muscles, which produced difficulty in the movility of the neck and coordinated translation. It is well known that this findings are due to a deficiency of selenium and vitamin E, giving them as diagnostic parameters for the presentation of this disease in horses, so we determined the enzyme activity of erythrocyte glutathione peroxidase (GSH-Px), yielding results very low. This condition is also known as yellow fat disease or steatitis in horses and produces degeneration of adipose tissue which is replaced by connective tissue and calcium deposits and may be associated with nutritional or dystrophic miodegeneration (white muscle disease). As far as we know this is the first report of steatosis in donkeys (Equus asinus) in Colombia.

  11. Esteatosis en un burro (Equus asinus. Primer reporte en Colombia

    Directory of Open Access Journals (Sweden)

    José Cardona Á.

    2011-12-01

    Full Text Available Se describe un caso de esteatosis en un burro (Equus asinus, castrado, de 15 años de edad, procedente del municipio de San Antero (Córdoba, Colombia, al cual se le detectó ligamento nucal engrosado, duro y doloroso, dando la impresión de un doble cuello y edemas subcutáneos indurados en pared costal, abdominal y pectoral. Tambiénpresentó masas duras en la unión de músculos semimembranoso y semitendinoso. Por todo lo anterior, mostró dificultad para realizar movimientos coordinados del cuello, nuca y de traslado. Estos hallazgos obedecen principalmente a una deficiencia de selenio y vitamina E, sirviendo como parámetro diagnóstico para la identificación de esta enfermedad en equinos, por lo cual se determinó la actividad eritrocitica de la enzima glutatión peroxidada (GSH-Px, arrojando resultados muy bajos. Este cuadro es también conocido en equinos como enfermedad de la grasa amarilla o esteatitis, que produce degeneración del tejido adiposo, siendo reemplazado por tejido conectivo con depósitos de calcio. Puede estar asociada a miodegeneración nutricional o distrófica (enfermedad del músculo blanco. Es el primer reporte de esta enfermedad en burros(Equus asinus que se hace en Colombia.

  12. Nuevo registro de Equus (Amerhippus) santaeelenae (Mammalia, Perissodactyla) del pozo de asfalto de Inciarte (Pleistoceno Superior), estado Zulia, Venezuela / New record of Equus (Amerhippus) santaeelenae (Mammalia, Perissodactyla) from the Pozo de asfalto de Inciarte site (Late Pleistocene), Zulia State, Venezuela

    Scientific Electronic Library Online (English)

    Ascanio D., Rincón R.; María Teresa, Alberdi; José Luis, Prado.

    2006-09-01

    Full Text Available Los fósiles de Equidae del pozo de asfalto de Inciarte son descritos y determinados taxonómicamente. Se han comparado los p3-4 inferiores de Inciarte con los de Equus (Amerhippus) andium, Equus (A.) santaeelenae, Equus (A.) insulatus y Equus (A.) neogeus de varias localidades de América del Sur medi [...] ante análisis multivariante. Los resultados de este análisis indican que la especie Equus (Amerhippus) santaeelenae (Spillmann) está representada en el yacimiento. Se discuten sus implicaciones paleoecológicas. Algunos autores sugieren que un estrés nutricional, producto de un cambio rápido en las comunidades vegetales, podría ser una de las causas que expliquen la extinción de fines del Pleistoceno. La especialización en la dieta que se atribuye a esta especie es una evidencia en favor de esta teoría. Abstract in english Fossil remains of Equidae from the asphaltic well of Inciarte quarry are described and taxonomically determined. We compared the lower p3-4 from Inciarte with Equus (Amerhippus) andium, Equus (A.) santaeelenae, E. (A.) insulatus and Equus (A.) neogeus remains from several localities in South America [...] using multivariate analysis. The results of this analysis indicate that Equus (Amerhippus) santaeelenae (Spillmann) is represented in the quarry. Its paleoecological implications are discussed. The resource partitioning preference of this species supports the several nutritional hypotheses to explain latest Pleistocene extinctions.

  13. Analysis of fertilization and polyspermy in serotonin-spawned eggs of the zebra mussel, Dreissena polymorpha.

    Science.gov (United States)

    Misamore, M; Silverman, H; Lynn, J W

    1996-02-01

    Eggs isolated from animals spawned with 10(-3) M serotonin were inseminated with sperm concentrations ranging from 10(3)-10(6) sperm/ml. Multiple sperm attached to the surface of the egg and sperm incorporation occurred within 3 min postinsemination (PI). Sperm mitochondria, centrioles, and flagellum were also incorporated. Incorporation was essentially complete by 6 min PI. In the egg cortex, the sperm head rotated 180 degrees, and a rapid translocation of the sperm through the cytoplasm towards the egg interior began by 5-6 min PI. In heavily polyspermic inseminations, translocations of the sperm were either minimal or nonexistent. In monospermic eggs, nuclear decondensation occurred after translocation was complete, beginning by 9-10 min PI. A male pronucleus began to develop in the cytoplasm by 21 min PI and enlarged to 20 microns before fusing with the female pronucleus. Oscillation of the egg cytoplasm and mitotic spindle apparatus was observed immediately prior to cleavage. Cleavage occurred at 60 min PI. Sperm incorporation and pronuclear formation were confirmed with fluorescent and confocal microscopy using the DNA-specific dyes Hoescht 33342 and 7-aminoactinomycin D. In sperm concentrations > 10(4) sperm/ml, 26-76% of the eggs exhibited polyspermy. The high incidence of polyspermy suggests that rapid, effective blocks to polyspermy were not present or were ineffective in a significant proportion of serotonin-spawned eggs. PMID:8824919

  14. Frequency variations of solar radio zebras and their power-law spectra.

    Czech Academy of Sciences Publication Activity Database

    Karlický, Marian

    2014-01-01

    Ro?. 561, January (2014), A34/1-A34/4. ISSN 0004-6361 R&D Projects: GA ?R GAP209/12/0103 Grant ostatní: EU(XE) PIRSES-GA-2011-295272 Institutional support: RVO:67985815 Keywords : Sun * radio radiation * plasmas Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 4.479, year: 2013

  15. Genotoxicity and activation of cellular defenses in transplanted zebra mussels Dreissena polymorpha along the Seine river.

    Science.gov (United States)

    Châtel, Amélie; Faucet-Marquis, Virginie; Gourlay-Francé, Catherine; Pfohl-Leszkowicz, Annie; Vincent-Hubert, Françoise

    2015-04-01

    The aim of the present study was to confirm the relevance of studying DNA adduct formation in a field study. In that context, freshwater mussels Dreissena polymorpha, collected in a reference station, were transplanted in different sites with a pollution gradient. After one and two months, mussels were collected and DNA adduct formation was analyzed using the (32)P post labelling technique on both gills and digestive glands. In addition, the expression of genes involved in the detoxification system (catalase (CAT), superoxide dismutase (SOD), glutathione S-transferase (GST), HSP70, aryl hydrocarbon receptor (AHR), P glycoprotein (PgP), metallothionein (MT)) was assessed by RT-PCR. DNA adducts were observed at amount comparable to data from literature. Increase of DNA adducts after two months of transplantation could be correlated with strong modulation of gene expression implicated in detoxification processes. Indeed, PgP and HSP70 gene expressions were similarly induced in gills and digestive glands while SOD and CAT expressions were down regulated in both tissues. AHR, GST and MT genes were differently regulated depending upon the tissue studied and the level of contamination in the different sites. We demonstrated that mussels transplanted in the different stations with pollution gradient were able to biotransform PAHs, assessed by DNA adduct formation and the high decrease of detoxification genes. Specific DNA adducts pattern obtained after one and two month mussel transplantations demonstrated the relevance of DNA adduct as biomarker of environmental pollution. PMID:24951272

  16. Variation in the volume of zebra finch song control nuclei is heritable: developmental and evolutionary implications.

    OpenAIRE

    Airey, D. C.; Castillo-juarez, H.; Casella, G.; Pollak, E. J.; Devoogd, T. J.

    2000-01-01

    In many songbird species, females prefer males that sing a larger repertoire of syllables. Males with more elaborate songs have a larger high vocal centre (HVC) nucleus, the highest structure in the song production pathway. HVC size is thus a potential target of sexual selection. Here we provide evidence that the size of the HVC and other song production nuclei are heritable across individual males within a species. In contrast, we find that heritabilities of other nuclei in a song-learning p...

  17. Grazing rate of zebra mussel in a shallow eutrophicated bay of the Baltic Sea.

    Science.gov (United States)

    Oganjan, Katarina; Lauringson, Velda

    2014-12-01

    Benthic suspension feeding is an important process in coastal ecosystems. Among all the World's oceans, coastal ecosystems are the most modified by human impact and changing at accelerating pace. It is complicated to understand, how various environmental factors affect feeding rates of suspension feeders in their natural habitats. Thus, shapes of such relationships are poorly described for several intersections of environmental gradients. In this study, relationships between grazing rates of an invasive bivalve Dreissena polymorpha and ambient environmental factors were investigated in a turbid eutrophic bay of the central Baltic Sea using a novel modelling method of Boosted Regression Trees (BRT), a statistical tool able to handle non-normal distributions, complex relationships, and interactive effects. Feeding rates of mussels were derived from field populations by measuring the content of algal pigments in specimens collected from their natural habitat. The content of pigments was converted to feeding rate separately each time using field experiments measuring simultaneously the content of pigments and biodeposition of mussels. The results suggest that feeding rates of D. polymorpha are related to several environmental factors which gradients outreach the optimal range for the local mussel population. All the observed effects were non-linear with complex shapes. Variability along the resource gradient was the most important predictor of mussel feeding, followed by salinity and disturbance caused by wind. The most important interaction occurred between disturbance and resource gradient, while feeding function showed more plasticity along the latter. Mapping of environmental tipping points with the aid of machine learning methods may enable to concentrate the most relevant information about ecological functions worldwide. PMID:24933437

  18. Behavioral and neural lateralization of vision in courtship singing of the zebra finch.

    Science.gov (United States)

    George, Isabelle; Hara, Erina; Hessler, Neal A

    2006-09-01

    Along with human speech and language processing, birdsong has been one of the best-characterized model systems for understanding the relationship of lateralization of brain function to behavior. Lateralization of song production has been extensively characterized, and lateralization of song perception has begun to be studied. Here we have begun to examine whether behavior and brain function are lateralized in relation to communicative aspects of singing, as well. In order to monitor central brain function, we assayed the levels of several activity dependent immediate early genes after directed courtship singing. Consistent with a lateralization of visual processing during communication, there were higher levels of expression of both egr-1 and c-fos in the left optic tectum after directed singing. Because input from the eyes to the brain is almost completely contralateral in birds, these results suggest that visual input from the right eye should be favored during normal singing to females. Consistent with this, we further found that males sang more when they could use only their right eye compared to when they could use only their left eye. Normal levels of singing, though, required free use of both eyes to view the female. These results suggest that there is a preference for visual processing by the right eye and left brain hemisphere during courtship singing. This may reflect a proposed specialization of the avian left hemisphere in sustaining attention on stimuli toward which a motor response is planned. PMID:16838371

  19. When you hear hoofbeats, think of horses but do not forget the zebras.

    Science.gov (United States)

    Stochholm, Anders; Løgstrup, Brian Bridal

    2015-01-01

    We report a case of a 68-year-old man who was admitted to the department of cardiology with increasing abdominal and chest pain during the day. The prehospital ECG showed clear ST segment elevation in inferior leads. The patient was routed directly to the catheterisation laboratory with acute myocardial infarction as a tentative diagnosis. The coronary angiography showed an occluded right coronary artery that was reopened with a plain old balloon angioplasty procedure. After the procedure, the patient was expected to feel better, but the abdominal pain worsened. The following bedside ultrasound examination was quite surprising. PMID:25791520

  20. A Social Relations Model for the Colonial Behavior of the Zebra Finch

    Directory of Open Access Journals (Sweden)

    Vanya Alessandra Moreno

    2010-01-01

    Full Text Available A social relations model was developed for 5 years of behavioral recordings from a captive colony of Zebrafinches (Taeniopygia guttata. A quantitative ethogram was applied, using one-zero focal animal sampling on an ethologically comprehensive checklist of 52 behavioral items (Figueredo, Petrinovich, & Ross, 1992. Of the 9 ethological factors previously identified, only 4 of the 6 social factors (Social Proximity, Social Contact, Social Submission, and Social Aggression were used. Major results were as follows: (1 Individual finches showed systematically different response dispositions that were stable over a 5-year period as both subjects and objects of behavior; (2 Interactions between finches differed systematically by the sexes of both the subjects and the objects of behavior; (3 Behavioral interactions between finches and their mates differed systematically according to the subjects' sex, but also differed systematically from those with other members of the objects' sex; (4 Behavioral interactions between finches and their relatives differed systematically between different discrete categories of relatives, but did not vary as a systematic function of either graded genetic relatedness or familiarity due to common rearing; and (5 Behavioral interactions between finches and their relatives showed an overall bias towards preferential interactions with male relatives.

  1. Immediate and delayed effects of growth conditions on ageing parameters in nestling zebra finches.

    Science.gov (United States)

    Reichert, Sophie; Criscuolo, François; Zahn, Sandrine; Arrivé, Mathilde; Bize, Pierre; Massemin, Sylvie

    2015-02-01

    Conditions experienced during development and growth are of crucial importance as they can have a significant influence on the optimisation of life histories. Indeed, the ability of an organism to grow fast and achieve a large body size often confers short- and long-term fitness benefits. However, there is good evidence that organisms do not grow at their maximal rates as growth rates seem to have potential costs on subsequent lifespan. There are several potential proximate causes of such a reduced lifespan. Among them, one emerging hypothesis is that growth impacts adult survival and/or longevity through a shared, end point, ageing mechanism: telomere erosion. In this study, we manipulated brood size in order to investigate whether rapid growth (chicks in reduced broods) is effectively done at the cost of a short- (end of growth) and long-term (at adulthood) increase of oxidative damage and telomere loss. Contrary to what we expected, chicks from the enlarged broods displayed more oxidative damage and had shorter telomeres at the end of the growth period and at adulthood. Our study extends the understanding of the proximate mechanisms involved in the trade-off between growth and ageing. It highlights that adverse environmental conditions during growth can come at a cost via transient increased oxidative stress and pervasive eroded telomeres. Indeed, it suggests that telomeres are not only controlled by intrinsic growth rates per se but also may be under the control of some extrinsic environmental factors, which could complicate our understanding of the growth-ageing interaction. PMID:25524985

  2. When the zebra loses its stripes: Semantic priming in early Alzheimer's disease and semantic dementia.

    OpenAIRE

    Laisney, Mickae?l; Giffard, Be?ne?dicte; Belliard, Serge; La Sayette, Vincent; Desgranges, Be?atrice; Eustache, Francis

    2011-01-01

    Patients suffering from Alzheimer's disease (AD) or semantic dementia (SD) both exhibit deficits on explicit tasks of semantic memory. Semantic priming (SP) paradigms provide a very pure and precise implicit measurement of semantic memory impairment, and a previous study of AD (Giffard et al., 2002) using one such paradigm revealed that AD patients in the initial stages of semantic deterioration presented an abnormally large priming effect (hyperpriming) in a category-coordinate condition, c...

  3. Zebra Mussel Farming in the Szczecin (Oder) Lagoon: Water-Quality Objectives and Cost-Effectiveness

    OpenAIRE

    Thomas Neumann; Nardine Stybel; Gerald Schernewski

    2012-01-01

    The Oder (Szczecin) Lagoon in the southern Baltic Sea is a heavily eutrophicated and degraded coastal ecosystem. We applied a systems approach framework to critically evaluate whether existing water-management measures achieve water-quality objectives for the river and lagoon systems. Our simulations reveal that the existing water-quality objectives for the river and the coastal waters are not sufficiently complementary. We suggest new water-quality threshold concentrations, which are in agre...

  4. Statistics and Classification of the Microwave Zebra Patterns Associated with Solar Flares.

    Czech Academy of Sciences Publication Activity Database

    Tan, B.; Tan, Ch.; Zhang, Y.; Mészárosová, Hana; Karlický, Marian

    2014-01-01

    Ro?. 780, ?. 2 (2014), 129/1-129/9. ISSN 0004-637X R&D Projects: GA ?R GAP209/12/0103 Institutional support: RVO:67985815 Keywords : Sun activity * activity * flares Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 6.280, year: 2013

  5. Genotoxicity and activation of cellular defenses in transplanted zebra mussels Dreissena polymorpha along the Seine river

    OpenAIRE

    Chatel, Amelie; Faucet-marquis, Virginie; Gourlay-france, Catherine; Pfohl-leszkowicz, Annie; Vincent-hubert, Francoise

    2015-01-01

    The aim of the present study was to confirm the relevance of studying DNA adduct formation in a field study. In that context, freshwater mussels Dreissena polymorpha, collected in a reference station, were transplanted in different sites with a pollution gradient. After one and two months, mussels were collected and DNA adduct formation was analyzed using the 32P post labelling technique on both gills and digestive glands. In addition, the expression of genes involved in the detoxification sy...

  6. A re-assessment of the avifauna of the Mountain Zebra National Park

    Directory of Open Access Journals (Sweden)

    P.E. Hilley

    2005-06-01

    Full Text Available Based on all published records, together with the original data for the southern African bird atlas, the current Birds in Reserves Project and our records on field trips, 257 bird species have been reliably recorded from MZNP. We have assessed the current status of all species, in relation to the recent expansion of the park and other changes which may be a consequence of management practices. No birds of national conservation concern are breeding residents in the park, and some species are periodic or irregular visitors. Nevertheless, the park is important for the conservation of representatives of the Karoo avifauna, and the diversity of birdlife present should be highlighted to attract visitors with a special interest in birding.

  7. Improved cycling behavior of ZEBRA battery operated at intermediate temperature of 175°C

    Energy Technology Data Exchange (ETDEWEB)

    Li, Guosheng; Lu, Xiaochuan; Kim, Jin Yong; Lemmon, John P.; Sprenkle, Vincent L.

    2014-01-01

    Operation of the sodium-nickel chloride battery at temperatures below 200°C reduces cell degradation and improves cyclability. One of the main technical issues with operating this battery at intermediate temperatures such as 175°C is the poor wettability of molten sodium on ?”-alumina solid electrolyte (BASE), which causes reduced active area and limits charging. In order to overcome the poor wettability of molten sodium on BASE at 175°C, a Pt grid was applied on the anode side of the BASE using a screen printing technique. Cells with their active area increased by metallized BASEs exhibited deeper charging and stable cycling behavior.

  8. A note on the smaller mammals of the Mountain Zebra National Park

    Directory of Open Access Journals (Sweden)

    J. J. L. Pretorius

    1971-05-01

    Full Text Available Collecting in April 1971 yielded 74 specimens of 16 species. Of these, seven species (Elephantulus rupestris, Lepus saxatilis, Pronolagus crassicaudatus, Graphiurus murinus, Aethomys namaquensis, Desmodillus auricularis and Gerbillurus paeba are new records for the park. Distribution in habitat-types for each species known to occur are described.

  9. Improved cycling behavior of ZEBRA battery operated at intermediate temperature of 175°C

    Energy Technology Data Exchange (ETDEWEB)

    Li, Guosheng; Lu, Xiaochuan; Kim, Jin Yong; Lemmon, John P.; Sprenkle, Vincent L.

    2014-03-01

    Operation of sodium-nickel chloride battery at temperatures lower than 200°C reduces cell degradation and improves the cyclability. One of the main technical issues in terms of operating this battery at intermediate temperatures such as 175°C is the poor wettability of sodium melt on ?”-alumina solid electrolyte (BASE) causing reduced active area and limited charging . In order to overcome the problem related to poor wettability of Na melt on BASE at 175°C, Pt grid was applied on the anode side of BASE using a screen printing technique. Deeper charging and improved cycling behavior was observed on the cells with metalized BASEs due to extended active area.

  10. Effects of sex steroids on spatial cognition in the zebra finch (Taeniopygia guttata)

    OpenAIRE

    Haggis, Olivia

    2010-01-01

    It is well established in mammals that chronic, long-term elevations in sex steroids are associated with improvements in spatial cognition. It is less clear the extent to which short to medium term elevations in sex steroids improve spatial cognition and change hippocampal morphology, particularly in birds. The avian hippocampus expresses both androgen receptors (AR) and oestrogen receptor alpha (ER?) and high levels of the enzyme aromatase that converts testosterone to oestro...

  11. Measurement and analysis of reaction rates in radial breeder regions of Zebra Assembly 13

    International Nuclear Information System (INIS)

    Foil activation techniques have been used to study the major contributions of the power output from the radial breeder region of an operating mock-up of the Prototype Fast Reactor. Three breeder configurations have been investigated; a clean uranium-oxide breeder, an irradiated uranium-oxide breeder, and a uranium-carbide breeder. Predictions of the power distributions have been made using FGL5 data with both diffusion and transport theory models. It has been shown that the standard diffusion theory treatment may lead to errors of about 10% in breeder power relative to that in the core but that significant improvements are obtained by the use of transport theory. (author)

  12. Measurement and analysis of reaction rates in radial breeder regions of Zebra assembly 13

    International Nuclear Information System (INIS)

    Foil activation techniques have been used to study the major contributions to the power output from the radial breeder region of an operating mock-up of the Prototype Fast Reactor. Three breeder configurations have been investigated; a clean uranium-oxide breeder, an irradiated uranium-oxide breeder, and a uranium-carbide breeder. Predictions of the power distributions have been made using FGL5 data with both diffusion and transport theory models. It has been shown that the standard diffusion theory treatment may lead to errors of about 10% in breeder power relative to that in the core but that significant improvements are obtained by the use of transport theory. (author)

  13. A Very Small and Super Strong Zebra Pattern Burst at the Beginning of a Solar Flare.

    Czech Academy of Sciences Publication Activity Database

    Tan, B.; Tan, Ch.; Zhang, Y.; Huang, J.; Mészárosová, Hana; Karlický, Marian; Yan, Y.

    2014-01-01

    Ro?. 790, ?. 2 (2014), 151/1-151/6. ISSN 0004-637X R&D Projects: GA ?R GAP209/12/0103 Institutional support: RVO:67985815 Keywords : Sun: activity * Sun: flares * Sun: particle emission Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 6.280, year: 2013

  14. Tallinnas Narva mnt. 7 asuva kohviku Zebra sisekujundus / Tiiu Truus, Tiiu Prisko, Mati Veermets...[jt.

    Index Scriptorium Estoniae

    2006-01-01

    põhiplaan, 11 värv. vaadet; fotod: Kalle Veesaar; laes olevate dekoratiivsete lippude graafiline kujundus on Tiiu Priskolt ja Mati Veermetsalt, tualettruumi looduskivist valamu ja põrandavaasi autor on Kaido Kivi

  15. Genesis of self-organized zebra textures in burial dolomites : displacive veins, induced stress, and dolomitization

    OpenAIRE

    Merino, E.

    2006-01-01

    The dolomite veins making up rhythmites common in burial dolomites are not cement infillings of supposed cavities, as in the prevailing view, but are instead displacive veins, veins that pushed aside the host dolostone as they grew. Evidence that the veins are displacive includes a) small transform-fault-like displacements that could not have taken place if the veins were passive cements, and b) stylolites in host rock that formed as the veins grew in order to compensate for the volume added ...

  16. The development of sex recognition in the zebra finch. Sexual imprinting from an evolutionary perspective

    OpenAIRE

    Vos, David Rudolph

    1995-01-01

    In deze studie onderzoek ik een aantal aspecten van het proces van sexuele inprenting en de wijze waarop dit proces de partnervoorkeur van zebravink vrouwtjes en mannetjes beïnvloedt tegen de achtergrond van de potentiële evolutionaire consequenties voor het uiterlijk van vogels. ... Zie: Samenvatting

  17. Developmental stress affects song learning but not song complexity and vocal amplitude in zebra finches

    OpenAIRE

    Brumm, Henrik; Zollinger, Sue Anne; Slater, Peter J.B

    2009-01-01

    Several recent studies have tested the hypothesis that song quality in adult birds may reflect early developmental conditions, specifically nutritional stress during the nestling period. Whilst all of these earlier studies found apparent links between early nutritional stress and song quality, their results disagree as to which aspects of song learning or production were affected. In this study, we attempted to reconcile these apparently inconsistent results. Our study also provides the first...

  18. Toxico-kinetic, chemical and radiological toxicity of uranium on zebra fish (Danio rerio)

    International Nuclear Information System (INIS)

    This thesis explores the toxico-kinetic and toxicological aspects of uranium in fish. Uranium, appears to be highly bio accumulated and bio concentrated in fish. It spreads all through the whole organism. Nevertheless, its distribution is heterogeneous (gills and liver being the main sites of accumulation).From a toxicological point of view, we notice perturbations of the antioxidant system (inhibitions of hepatic Sod, Cat and G Px activities; depletion of total GSH) and of the cholinergic system (inhibition/over-activation of brain AChE). Genotoxic effects also appear in red blood cells, hepatocytes and gonad cells. The kinetics of these biochemical perturbations depend on the radiological activity of uranium, responses appearing earlier with increasing delivered activity. Histological effects (differing in types depending on delivered radiological activity) are also observed (in gills and muscles). (author)

  19. Audience Effect Alters Male Mating Preferences in Zebra Finches (Taeniopygia guttata)

    OpenAIRE

    Dubois, Fre?de?rique; Belzile, Alexandra

    2012-01-01

    The social environment of animals strongly influences the mating preferences of both the choosing and the observing individuals. Notably, there is recent evidence that polygamous males decrease their selectivity when being observed by competitors in order to direct their rivals’ attention away from their true interest and, consequently, reduce sperm competition risk. Yet, other mechanisms, whose importance remains unexplored, could induce similar effects. In monogamous species with mutual c...

  20. Growth of a male Caracal kitten felis Caracal in the Mountain Zebra National Park

    Directory of Open Access Journals (Sweden)

    J. H Grobler

    1982-11-01

    Full Text Available Three caracal (lynx Fells caracal kittens, two females and a male were received from the Fish River area some 50 km north of Cradock, Republic of South Africa, on the 20th March 1980. These were found at the base of a dense Rhus erosa bush on the side of a hill and estimated at 14 days old based on the findings of Cade (1968 Int. Zoo Yb. 45 and Kralik (1967 Int. Zoo Yb. 132.

  1. One-year monitoring of reproductive and energy reserve cycles in transplanted zebra mussels (Dreissena polymorpha).

    Science.gov (United States)

    Palais, F; Mouneyrac, C; Dedourge-Geffard, O; Giambérini, L; Biagianti-Risbourg, S; Geffard, A

    2011-05-01

    A 12-month active biomonitoring study was performed in 2008-2009 on a northern French river system using the freshwater mussel Dreissena polymorpha as a sentinel species. Allochtonous mussels originating from a reference site (Commercy) were caged at four sites (Bouy, Sept-Saulx, Fismes, Ardre) within the Vesle River basin. The main objective of the study was to characterize the influence of biotic (sex, food availability) and abiotic (temperature, chemicals) factors on the reproductive and energy reserve (glycogen, lipids) cycles of exposed mussels. Both cycles were markedly disturbed at the Bouy and Sept-Saulx sites where the lowest chlorophyll a levels were recorded during the study. At these sites, mussels obviously faced a negative energy balance, as confirmed by the impairment of their physiological state and byssal attachment. At other exposure sites, reproductive and energy reserves cycles were less impacted but were still dependent on the nutritional state of mussels. The latter appeared as a significant natural confounding factor in ecotoxicological survey performed in low polluted areas. PMID:21345479

  2. Activities of 3?-HSD and Aromatase in Slices of Developing and Adult Zebra Finch Brain

    OpenAIRE

    Tam, Helen; Schlinger, Barney A.

    2006-01-01

    Sex steroids influence the development and function of the songbird brain. Developmentally, the neural circuitry underlying song undergoes masculine differentiation under the influence of estradiol. In adults, estradiol stimulates song behavior and the seasonal growth of song control circuits. There is good reason to believe that these neuroactive estrogens are synthesized in the brain. At all ages, estrogens could act at the lateral ventricle, during migration, or where song nuclei exist or ...

  3. Mitochondrial phylogenomics of modern and ancient equids

    DEFF Research Database (Denmark)

    Vilstrup, Julia T; Seguin-Orlando, Andaine

    2013-01-01

    The genus Equus is richly represented in the fossil record, yet our understanding of taxonomic relationships within this genus remains limited. To estimate the phylogenetic relationships among modern horses, zebras, asses and donkeys, we generated the first data set including complete mitochondrial sequences from all seven extant lineages within the genus Equus. Bayesian and Maximum Likelihood phylogenetic inference confirms that zebras are monophyletic within the genus, and the Plains and Grevy's zebras form a well-supported monophyletic group. Using ancient DNA techniques, we further characterize the complete mitochondrial genomes of three extinct equid lineages (the New World stilt-legged horses, NWSLH; the subgenus Sussemionus; and the Quagga, Equus quagga quagga). Comparisons with extant taxa confirm the NWSLH as being part of the caballines, and the Quagga and Plains zebras as being conspecific. However, the evolutionary relationships among the non-caballine lineages, including the now-extinct subgenus Sussemionus, remain unresolved, most likely due to extremely rapid radiation within this group. The closest living outgroups (rhinos and tapirs) were found to be too phylogenetically distant to calibrate reliable molecular clocks. Additional mitochondrial genome sequence data, including radiocarbon dated ancient equids, will be required before revisiting the exact timing of the lineage radiation leading up to modern equids, which for now were found to have possibly shared a common ancestor as far as up to 4 Million years ago (Mya).

  4. Trained Quantity Abilities in Horses (Equus caballus): A Preliminary Investigation.

    Science.gov (United States)

    Miletto Petrazzini, Maria Elena

    2014-09-01

    Once believed to be a human prerogative, the capacity to discriminate between quantities now has also been reported in several vertebrates. To date, only two studies investigated numerical abilities in horses (Equus caballus) but reported contrasting data. To assess whether horses can be trained to discriminate between quantities, I have set up a new experimental protocol using operant conditioning. One adult female was trained to discriminate between 1 and 4 (Test 1) in three different conditions: non-controlled continuous variables (numerical and continuous quantities that co-vary with number are simultaneously available), 50% controlled continuous variables (intermediate condition), and 100% controlled continuous variables (only numerical information available). The subject learned the discrimination in all conditions, showing the capacity to process numerical information. When presented with a higher numerical ratio (2 vs. 4, Test 2), the subject still discriminated between the quantities but its performance was statistically significant only in the non-controlled condition, suggesting that the subject used multiple cues in presence of a more difficult discrimination. On the whole, the results here reported encourage the use of this experimental protocol as a valid tool to investigate the capacity to process numerical and continuous quantities in horses in future research. PMID:25379278

  5. Trained Quantity Abilities in Horses (Equus caballus: A Preliminary Investigation

    Directory of Open Access Journals (Sweden)

    Maria Elena Miletto Petrazzini

    2014-07-01

    Full Text Available Once believed to be a human prerogative, the capacity to discriminate between quantities now has also been reported in several vertebrates. To date, only two studies investigated numerical abilities in horses (Equus caballus but reported contrasting data. To assess whether horses can be trained to discriminate between quantities, I have set up a new experimental protocol using operant conditioning. One adult female was trained to discriminate between 1 and 4 (Test 1 in three different conditions: non-controlled continuous variables (numerical and continuous quantities that co-vary with number are simultaneously available, 50% controlled continuous variables (intermediate condition, and 100% controlled continuous variables (only numerical information available. The subject learned the discrimination in all conditions, showing the capacity to process numerical information. When presented with a higher numerical ratio (2 vs. 4, Test 2, the subject still discriminated between the quantities but its performance was statistically significant only in the non-controlled condition, suggesting that the subject used multiple cues in presence of a more difficult discrimination. On the whole, the results here reported encourage the use of this experimental protocol as a valid tool to investigate the capacity to process numerical and continuous quantities in horses in future research.

  6. Population viability analysis on domestic horse breeds (Equus caballus)

    DEFF Research Database (Denmark)

    Thirstrup, Janne Pia; Bach, Lars

    2009-01-01

    In this study, we performed a population viability analysis on 3 domestic horse breeds (Equus caballus) of Danish origin, namely, the Frederiksborg, the Knabstrupper, and the Jutland breeds. Because of their small population sizes, these breeds are considered endangered. The Vortex software simulation package was used for the population viability analysis. First, we investigated the future viability of these breeds based on present demographic and environmental parameters. Second, a sensitivity analysis revealed the most important variables for the viability of these breeds. Third, we examined management scenarios in which one of the studbooks was closed. According to the Vortex analysis, 2 of the breeds (Knabstrupper and Jutland) will persist for the next 200 yr, whereas the smaller breed (Frederiksborg) could become extinct within 40 yr. The sensitivity analyses indicated that the variables concerning reproduction of the mares had the greatest impact, with the number of mares actively breeding being the most influential on the population forecasts. The results suggest that closing the Knabstrupper studbooks can be done only if increasing the number of mares actively breeding counteracts the loss of genetic variation attributable to such a management strategy. It is recommended, based on these results, that the number of Frederiksborg and Knabstrupper mares actively breeding must be increased to approximately 30% in the 2 breeds that are presently using only 13%, while leaving the third (Frederiksborg ) at its present 30% level. Monitoring of the breeds in the future, however, may be exploited to adjust the breeding strategies. We suggest that the large amount of data required by Vortex makes it very useful for analyzing domestic animals because of the comprehensive data material often available. The results of this analysis accord with other studies on the Prezwalski horse, indicating robustness in the parameter sensitivity for horses.

  7. Characteristics of the herbaceous layer in preferred grazing areas of six herbivore species in the south-eastern Kruger National Park

    OpenAIRE

    Rooyen, N.; Bothma, J. Du P.; Wentzel, J. J.

    1991-01-01

    The phytomass and species composition of the herbaceous layer in preferred grazing areas of zebra Equus burchellii, buffalo Syncerus caffer, waterbuck Kobus ellipsiprymnus, blue wildebeest Connochaetes taurinus, impala Aepyceros melampus and warthog Phacochoerusaethiopicus were investigated within the south-eastern portion of the Kruger National Park. The percentage frequency of herbaceous plants in Decreaser and Increaser categories, as determined by their reaction to different intensities o...

  8. Towards an adaptive management approach for the conservation of rare antelope in the Kruger National Park - outcome of a workshop held in May 2000

    OpenAIRE

    Walt, J. L.; Grant, C. C.

    2000-01-01

    A precipitous drop in rare antelope numbers specifically roan (Hippotragus equinis) sable (Hippotragus niger) and tsessebe (Damaliscus lunatus) since 1986 has become one of the main concerns of management. The zebra (Equus burchelli) population in the preferred habitats of these species had increased with the development of artificial waterpoints especial...

  9. Dietary shifts: do grazers become browsers in the Thicket Biome?

    Directory of Open Access Journals (Sweden)

    G.I.H. Kerley

    2001-07-01

    Full Text Available The diet of buffalo (Syncerus coffer and Burchell's zebra (Equus burchelli was investigated in the Addo Elephant National Park to test the hypothesis that the shortage of grass associated with thicket vegetation results in grazers increasing the proportion of dicotyledonous plant species in their diet. Diet composition, estimated from faecal analysis, indicated that 19 and 21 plant species were identified in the faeces of zebra and buffalo, respectively. Buffalo proved to have a higher percentage dicotyledonous (28.1 vs. 8.5 and lower percentage monocotyledonous (71.9 vs. 91.5 species in their diet than zebra. The grass Eragrostis curvula was found to be the dominant food item for both buffalo (18 of diet and zebra (39 of diet during the period of study. The present study indicated that a great proportion of the buffalo diet does in fact consist of grass, thereby refuting the perception that the Addo buffalo are primarily browsers. Both buffalo and zebra are specialised grazers and unsuited to a diet of browse. The probability of dietary shift by these grazers in the grass limited thicket vegetation is therefore challenged.

  10. Horse sense: social status of horses (Equus caballus) affects their likelihood of copying other horses’ behavior

    OpenAIRE

    Krueger, Konstanze; Heinze, Jürgen

    2008-01-01

    Animals that live in stable social groups need to gather information on their own relative position in the group’s social hierarchy, by either directly threatening or by challenging others, or indirectly and in a less perilous manner, by observing interactions among others. Indirect inference of dominance relationships has previously been reported from primates, rats, birds, and fish. Here, we show that domestic horses, Equus caballus, are similarly capable of soc...

  11. Reproduction and Development of the Released Przewalski’s Horses (Equus przewalskii) in Xinjiang, China

    OpenAIRE

    CHEN, Jinliang; WENG, Qiang; CHAO, Jie; HU, Defu; TAYA, Kazuyoshi

    2008-01-01

    In China, the first Przewalski’s horse (Equus przewalskii) group was released in Kalamaili Ungulate Protected Area in Xinjiang, in August 2001. The objective of this study was to investigate reproduction and development of released Przewalski’s horses in Xinjiang, China from 2002 to 2006. Twenty-four descendants were naturally born, average reproduction rate was 38.7%, and average survival rate of foals was 69.1% in this interim. Frequent alternation of the leading stallion and...

  12. Identificación de Especímenes de Equus grevyi en el Parque Zoológico Nacional de Cuba

    Directory of Open Access Journals (Sweden)

    Irina Fermin-Morales

    2014-07-01

    Full Text Available La cebra de Grevy (Equus grevyi se ha manejado a través de extracciones y reintroducciones de individuos desde su inclusión en la colección de animales del Parque Zoológico Nacional de Cuba. Para mejorar el manejo de esta especie es necesaria la identificación individual a través de caracteres morfológicos, por esto los que los investigadores se propusieron demostrar las diferencias en el patrón de rayado facial existente entre los individuos y entre ambos lados de un mismo individuo. El método de marcas naturales fue utilizado para la identificación de estos animales a través de fotografías. Las imágenes tomadas se compararon visualmente y se observó la diferencia existente en el patrón de rayado facial entre individuos y entre los lados faciales de un mismo individuo.Identification of Specimens in Equus grevyi in the Cuba National Zoo Park Abstract. Equus grevyi has managed through the extraction and the reintroduction of individuals from your entrance to the collection of animals of the Cuba National Zoo Park. To improve the handling of this species it is necessary the individual identification through morphological characters for those who proposed us demonstrate the differences in the owner of facial existent stripes between the individuals and between both patrons of a same individual. The outstanding method naturals were used for the identification of these animals through the photo. The taken images compared visual and it is observed the existent difference in the owner of facial stripes between individual and between the facial patrons of a same individual.

  13. ARTERIAL VASCULARIZATION OF THIMUS OF BRAZILIAN NORTHEASTERN DONKEY (Equus asinus VASCULARIZAÇÃO ARTERIAL DO TIMO EM FETOS DE JUMENTOS NORDESTINOS (Equus asinus

    Directory of Open Access Journals (Sweden)

    Marcelo Ismar Silva Santana

    2008-04-01

    Full Text Available There were utilised 10 fetuses of jumentos, males and females, to macroscopic study of the thymus vascularization. After the arteries injection, throught the aorta, with Neoprene Latx “450” solution, it was proceded the fixation, in a 10% formalin solution. It was observed that the thymus is reached by direct or indirect arterial branches coming from the right and left internal thoracic, left subclavian arterie, right superficial cervical, left extern thoracic and direct and indirect branches of left and right carotidas arteries. Thymus; vascularization; Equus asinus Foram utilizados 10 fetos de jumentos, machos e fêmeas, para o estudo macroscópico da vascularização do timo. Para a dissecção dos fetos, o conteúdo arterial recebeu solução aquosa a 50% de Neoprene Látex “450”, corada com pigmento específico, em seguida os fetos foram fixados em solução aquosa a 10% de formol. Observou-se que o timo era irrigado por colaterais oriundas das artérias torácicas internas direita e esquerda, da a. subclávia esquerda, da a. cervical superficial direita, da a. torácica externa esquerda e por ramos diretos e indiretos das aa. carótidas comuns direita e esquerda. Timo; vascularização; Equus asinus

  14. Sequencing and expression analysis of hepcidin mRNA in donkey (Equus asinus) liver / Sequenciamento e expressão do RNA mensageiro da hepcidina no fígado de jumentos (Equus asinus)

    Scientific Electronic Library Online (English)

    José P., Oliveira-Filho; Jessica A., Marques; Paulo Henrique J., Cunha; Gildenor X., Medeiros; Franklin, Riet-Correa; Vânia Maria V., Machado; Alexandre S., Borges.

    2012-10-01

    Full Text Available A hipoferremia observada durante os processos inflamatórios sistêmicos é mediada pela hepcidina, um peptídeo que é sintetizado predominantemente no fígado de mamíferos. A hepcidina desempenha um papel chave no metabolismo do ferro e no sistema imune. O aumento da expressão da hepcidina é particularm [...] ente útil durante a inflamação aguda, pois restringe a disponibilidade de ferro, necessária para o crescimento de microorganismos patogênicos. Neste estudo, o RNA mensageiro da hepcidina asinina foi caracterizado e sua expressão foi determinada em fígado de jumentos (Equus asinus). A sequência da hepcidina asinina tem uma janela de leitura de 261 nucleotídeos e a proteína correspondente é formada por 86 aminoácidos. A sequência de aminoácidos da hepcidina asinina foi mais homóloga à sequência da hepcidina equina (98%). A hepcidina madura (25 aminoácidos) foi 100% idêntica à hepcidina madura equina e possuía as oito cisteínas conservadas nas demais sequências de hepcidinas analisadas. O perfil de expressão da hepcidina no fígado de jumentos saudáveis foi alto e similar ao perfil de expressão do gene de referência. A sequência da hepcidina asinina foi depositada no GenBankTM (HQ902884) e será útil para o desenvolvimento de estudos adicionais sobre o metabolismo de ferro e inflamação nesta espécie. Abstract in english The hypoferremia that is observed during systemic inflammatory processes is mediated by hepcidin, which is a peptide that is mainly synthesized in the livers of several mammalian species. Hepcidin plays a key role in iron metabolism and in the innate immune system. It's up-regulation is particularly [...] useful during acute inflammation, and it restricts the iron availability that is necessary for the growth of pathogenic microorganisms. In this study, the hepcidin mRNA of Equus asinus has been characterized, and the expression of donkey hepcidin in the liver has been determined. The donkey hepcidin sequence has an open reading frame (ORF) of 261 nucleotides, and the deduced corresponding protein sequence has 86 amino acids. The amino acid sequence of donkey hepcidin was most homologous to Equus caballus (98%). The mature donkey hepcidin sequence (25 amino acids) was 100% homologous to the equine mature hepcidin and has eight conserved cysteine residues that are found in all of the investigated hepcidin sequences. The expression profile of donkey hepcidin in the liver was high and was similar to the reference gene expression. The donkey hepcidin sequence was deposited in GenBankTM (HQ902884) and may be useful for additional studies on iron metabolism and the inflammatory process in this species.

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

    OpenAIRE

    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 o...

  16. Odour-based natal nest recognition in the zebra finch (Taeniopygia guttata), a colony-breeding songbird

    OpenAIRE

    Caspers, Barbara A.; Krause, E. Tobias

    2010-01-01

    Passerine birds have an extensive repertoire of olfactory receptor genes. However, the circumstances in which passerine birds use olfactory signals are poorly understood. The aim of this study is to investigate whether olfactory cues play a role in natal nest recognition in fledged juvenile passerines. The natal nest provides fledglings with a safe place for sleeping and parental food provisioning. There is a particular demand in colony-breeding birds for fledglings to be able to identify the...

  17. Notes on the parasitology, pathology and bio-physiology of springbok in the Mountain Zebra National Park

    Directory of Open Access Journals (Sweden)

    P. A. Boyazoglu

    1973-07-01

    Full Text Available

    Thirteen species of parasitic metazoa and two protozoa have been identified. Pathological effects are described where applicable. Serological tests for virus diseases were negative but biochemical analyses revealed certain mineral deficiencies. The possible decimating effects of the former are discussed and appropriate guide lines for control suggested.

  18. Sometimes when you hear hoof beats, it could be a zebra: consider the diagnosis of Fabry disease

    Directory of Open Access Journals (Sweden)

    Burton James O

    2012-07-01

    Full Text Available Abstract Background Fabry disease is an X-linked lysosomal storage disorder that results from a deficiency of the enzyme ?-galactosidase A. Fabry disease is present in 4–5% of men with unexplained left ventricular hypertrophy or cryptogenic stroke. As enzyme replacement therapy is now more widely available, it is important to recognise the signs and symptoms of the disease and establish the diagnosis so that early treatment can be started before irreversible organ damage occurs. Case Presentation A previously fit and well 32-year-old Caucasian male presented with multisystem dysfunction including renal impairment. Although he had no suggestive symptoms, a diagnosis of Fabry disease was first established on a native renal biopsy. This was confirmed by enzymatic testing and subsequent genetic analysis that revealed a potentially new pathogenic variant. Conclusions This case highlights the importance both of Fabry disease as a differential diagnosis in patients with renal impairment in the context of multi-system disease and also of adequate tissue sampling for electron microscopy when performing native renal biopsies.

  19. Sometimes when you hear hoof beats, it could be a zebra: consider the diagnosis of Fabry disease

    Science.gov (United States)

    2012-01-01

    Background Fabry disease is an X-linked lysosomal storage disorder that results from a deficiency of the enzyme ?-galactosidase A. Fabry disease is present in 4–5% of men with unexplained left ventricular hypertrophy or cryptogenic stroke. As enzyme replacement therapy is now more widely available, it is important to recognise the signs and symptoms of the disease and establish the diagnosis so that early treatment can be started before irreversible organ damage occurs. Case Presentation A previously fit and well 32-year-old Caucasian male presented with multisystem dysfunction including renal impairment. Although he had no suggestive symptoms, a diagnosis of Fabry disease was first established on a native renal biopsy. This was confirmed by enzymatic testing and subsequent genetic analysis that revealed a potentially new pathogenic variant. Conclusions This case highlights the importance both of Fabry disease as a differential diagnosis in patients with renal impairment in the context of multi-system disease and also of adequate tissue sampling for electron microscopy when performing native renal biopsies. PMID:22849389

  20. A case of anaplastic large cell lymphoma: when you hear hoof beats, sometimes consider zebras, not horses

    Science.gov (United States)

    Sohatee, Mark Andrew

    2009-01-01

    A 22-year-old man presented with fever, lymphadenopathy and abdominal pain. With a travel history and considering the young age of the patient, an infective aetiology was thought most likely. Investigations yielded no evidence of infection. Given the increasing severity of the symptoms a neoplastic cause was subsequently considered. Following abdominal ultrasound and CT a lymph node and bone marrow biopsy were performed. These investigations revealed the diagnosis to be anaplastic large cell lymphoma. The patient consequently underwent a course of chemotherapy followed by a course of high-dose chemotherapy with an autologous bone marrow transplant. PMID:21918660

  1. Activation Changes in Zebra Finch (Taeniopygia guttata) Brain Areas Evoked by Alterations of the Earth Magnetic Field

    OpenAIRE

    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 influe...

  2. CYTO-GENOTOXIC EFFECTS OF SOME PHARMACEUTICAL AND PERSONAL CARE PRODUCTS (PPCPS) ON THE FRESHWATER BIVALVE ZEBRA MUSSEL (DREISSENA POLYMORPHA)

    OpenAIRE

    Parolini, Marco

    2010-01-01

    Pharmaceutical and personal care products (PPCPs) are an emerging class of environmental pollutants that are extensively and increasingly being used in human and veterinary medicine. Due to their continuous production, consumption and often abuse, many studies have shown worldwide measurable concentrations of about 100 of these drugs in the aquatic environment in the high ng L-1 to low µg L-1 range. Among these, antimicrobial, antibiotics and non-steroidal anti-inflammatory drugs (NSAIDs) ar...

  3. Long-term stability of grazing lawns in a small protected area, the Mountain Zebra National Park

    OpenAIRE

    Peter Novellie; Angela Gaylard

    2013-01-01

    We examined a heavily grazed plant community dominated by creeping grass species with the aim of, (1) determining its response to the exclusion of grazing and (2) its long-term persistence. This plant community was particularly favoured by wild ungulate species that prefer short grasses – blesbok (Damaliscus dorcas phillipsi), springbok (Antidorcas marsupialis) and black wildebeest (Connochaetes gnou). Exclusion of grazing by large herbivores by means of fencing resulted in the virtual disa...

  4. Identification of the first toll-like receptor gene in passerine birds: TLR4 orthologue in zebra finch (Taeniopygia guttata).

    Czech Academy of Sciences Publication Activity Database

    Vinkler, Michal; Bryjová, Anna; Albrecht, Tomáš; Bryja, Josef

    2009-01-01

    Ro?. 74, ?. 1 (2009), s. 32-41. ISSN 0001-2815 R&D Projects: GA AV ?R IAA600930608; GA MŠk LC06073 Institutional research plan: CEZ:AV0Z60930519 Keywords : avian immunogenetics * comparative immunology * evolutionary immunology Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.330, year: 2009

  5. Comparison of key enzymes in the zebra mussel, Dreissena polymorpha, the earthworm Allolobophora chlorotica and Chironomus riparius larvae.

    Science.gov (United States)

    Osman, A M; van Noort, P C M

    2007-06-01

    The levels of the enzymes, glutathione S-transferase, catalase, NAD(P)H-cytochrome c reductases, and DT-diaphorase were determined and compared in the tissues of three invertebrates commonly used in monitoring environmental quality: a freshwater mussel, Dreissena polymorpha, the earthworm Allolobophora chlorotica and the fourth instar of Chironomus riparius. It was found that the activities of GST, catalase, and NAD(P)-cytochrome c reductases were comparable in A. chlorotica and C. riparius, whereas comparatively a higher GST and a lower catalase activity was determined in the mussel tissues. DT-diaphorase was not detectable in A. chlorotica and the C. riparius larvae tissues, whereas this enzyme is present in the gills and the rest of soft mussel tissues (soft mussel tissues minus gills). It is suggested that the relatively low catalase activity observed in the tissues of the latter organism might be compensated by the presence of the antixidant role of DT-diaphorase. In addition, the inducibility of DT-diaphorase in D. polymorpha, by butylated hydroxyanisole (BHA) and lead (Pb) was investigated. Despite the bioaccumulation of both BHA (5.2+/-0.14 microgg(-1) wet weight) and Pb (233.7+/-0.95 mgkg(-1) dry weight) in the soft mussel tissues, the mussel DT-diaphorase was not induced. Although the activity of NADPH-cytochrome c (P-450) reductase was also not affected by these reagents, its activity was 2-fold higher in the gills than the rest of soft mussel tissues. PMID:17052754

  6. An indirect effect of biological invasions: the effect of zebra mussel fouling on parasitisation of unionid mussels by bitterling fish.

    Czech Academy of Sciences Publication Activity Database

    Vrtílek, Milan; Reichard, Martin

    2012-01-01

    Ro?. 696, ?. 1 (2012), s. 205-214. ISSN 0018-8158 R&D Projects: GA ?R GBP505/12/G112 Institutional support: RVO:68081766 Keywords : Non-native species * Coevolution * Invasional meltdown * Host-parasite relationship * Aquatic ecosystems Subject RIV: EG - Zoology Impact factor: 1.985, year: 2012

  7. A Study of the Survival and Oxygen Deficiency at the Zebra Mussel (Dreissena polymorpha Treated with Zinc (Zn

    Directory of Open Access Journals (Sweden)

    Bogdan N. Nikolov

    2009-07-01

    Full Text Available The current paper studies the change of respiratory rate and survival of Dreissena polymorpha at short exposure to zinc under laboratory conditions. The experiment is lasted 96h and three different concentrations of ZnSO4.7H2O were used - 0.5mg/l, 1.5mg/l; 2,0 mg/l. Survival and intensity of breathing of Dreissena polymorpha decreases with the increasing concentration of zinc in the water.

  8. An evaluation of the background introduced from the coded aperture mask in the low energy gamma-ray telescope ZEBRA

    International Nuclear Information System (INIS)

    The background which arises from the presence of a coded aperture mask is evaluated. The major contributions which have been considered here are the interactions with the mask of the isotropic gamma-ray background, a parallel gamma-ray beam, neutrons and the effect of the mask element profile. It is shown that none of these factors conbribute to a significant excess or modulation in the background counting rate over the detection plane. In this way the use of a passive rather than an active coded aperture mask is seen to be suitable for use in a low energy gamma-ray telescope. (orig.)

  9. Autoradiographic study on the distribution of 241Am in the shell of the freshwater zebra mussel Dreissena polymorpha

    International Nuclear Information System (INIS)

    Autoradiography was used to identify ?-track distributions in a series of shell sections from live mussels Dreissena polymorpha Pallas and dissected shells of dead mussels obtained from laboratory experiments using relatively high concentrations of 241Am in the exposure media, a required condition for successful use of this autoradiographic technique. A comparable distribution of ?-tracks was recorded on autoradiographs from both live and dead shells suggesting that metabolism does not lead to any sizable changes in the process of 241Am adsorption (present in the extrapallial fluid) onto the inner surface of shell. Autoradiographs showed a preferential accumulation of 241Am in the organic periostracum, whereas the outer and inner shell layers were characterized by a relatively low ?-tracks density. No ?-tracks were observed in the central part of the shell in any of the samples. These observations will be useful for the development of a general model to explain bioaccumulation and biosorption processes of radionuclides into mollusk shells. (author)

  10. Knockdown of FABP3 Impairs Cardiac Development in Zebra?sh through the Retinoic Acid Signaling Pathway

    Directory of Open Access Journals (Sweden)

    Xuejie Wang

    2013-07-01

    Full Text Available Fatty acid-binding protein 3 (FABP3 is a member of the intracellular lipid-binding protein family, and is primarily expressed in cardiac muscle tissue. Previously, we found that FABP3 is highly expressed in patients with ventricular-septal defects and is often used as a plasma biomarker in idiopathic dilated cardiomyopathy, and may play a significant role in the development of these defects in humans. In the present study, we aimed to investigate the role of FABP3 in the embryonic development of the zebrafish heart, and specifically how morpholino (MO mediated knockdown of FABP3 would affect heart development in this species. Our results revealed that knockdown of FABP3 caused significant impairment of cardiac development observed, including developmental delay, pericardial edema, a linear heart tube phenotype, incomplete cardiac loop formation, abnormal positioning of the ventricles and atria, downregulated expression of cardiac-specific markers and decreased heart rate. Mechanistically, our data showed that the retinoic acid (RA catabolizing enzyme Cyp26a1 was upregulated in FABP3-MO zebrafish, as indicated by in situ hybridization and real-time PCR. On the other hand, the expression level of the RA synthesizing enzyme Raldh2 did not significantly change in FABP3-MO injected zebrafish. Collectively, our results indicated that FABP3 knockdown had significant effects on cardiac development, and that dysregulated RA signaling was one of the mechanisms underlying this effect. As a result, these studies identify FABP3 as a candidate gene underlying the etiology of congenital heart defects.

  11. Long-term stability of grazing lawns in a small protected area, the Mountain Zebra National Park

    Directory of Open Access Journals (Sweden)

    Peter Novellie

    2013-08-01

    Full Text Available We examined a heavily grazed plant community dominated by creeping grass species with the aim of, (1 determining its response to the exclusion of grazing and (2 its long-term persistence. This plant community was particularly favoured by wild ungulate species that prefer short grasses – blesbok (Damaliscus dorcas phillipsi, springbok (Antidorcas marsupialis and black wildebeest (Connochaetes gnou. Exclusion of grazing by large herbivores by means of fencing resulted in the virtual disappearance of the creeping grasses and their replacement by tall tufted species. On plots that remained unfenced, the plant species composition was found to be little changed after an interval of more than 20 years. The number large stock unit equivalents (LSU per ha carried by the plant community was used as a proxy for grazing intensity. Monitored for approximately 2 years at the start of the study, LSU per ha was found to greatly exceed levels recommended for commercial livestock production. This plant community conforms to a recently published definition of a grazing lawn, in that intense grazing promotes palatable, grazing-tolerant grass species. Conservation implications: The positive association between grazers and grazing-tolerant grass species evidently persisted for more than 20 years and there was no evidence of an increase in abundance of unpalatable plant species. Despite the small size of the park, which limited the extent of large herbivore movements, localised heavy grazing did not lead to range degradation.

  12. TECHNOLOGICAL VALUE OF SPRING WHEAT OF ZEBRA CULTIVAR AS RELATED TO THE WAY OF NITROGEN AND MAGNESIUM APPLICATION

    Directory of Open Access Journals (Sweden)

    M RALCEWICZ

    2010-02-01

    Full Text Available A significant increase in grain yield was observed following soil fertilization with nitrogen up to the level of 90 kg·ha-1, independently of foliar fertilization. Among the examined variants of foliar fertilization on average, the significantly highest grain yield was obtained in the objects in which nitrogen and magnesium were administered in parallel. Within the entire range of nitrogen doses administered to soil, a moderately significant increase was noted in total protein content, to the level of 90 kg N·ha-1 a moderately increased content of wet gluten, sedimentation ratio and bread volume were recorded and following application of 60 kg N·ha-1 an increase in water absorbability of flour was observed. Independently of the soil fertilization with nitrogen, the most favourable of the studied variants of foliar fertilization for principal parameters of baking value proved to be a parallel application of nitrogen and magnesium or administration of nitrogen only.

  13. One-year monitoring of core biomarker and digestive enzyme responses in transplanted zebra mussels (Dreissena polymorpha).

    Science.gov (United States)

    Palais, F; Dedourge-Geffard, O; Beaudon, A; Pain-Devin, S; Trapp, J; Geffard, O; Noury, P; Gourlay-Francé, C; Uher, E; Mouneyrac, C; Biagianti-Risbourg, S; Geffard, A

    2012-04-01

    A 12-month active biomonitoring study was performed in 2008-2009 on the Vesle river basin (Champagne-Ardenne, France) using the freshwater mussel Dreissena polymorpha as a sentinel species; allochthonous mussels originating from a reference site (Commercy) were exposed at four sites (Bouy, Sept-Saulx, Fismes, Ardre) within the Vesle river basin. Selected core biomarkers (acetylcholinesterase (AChE) activity, glutathione-S transferase (GST) activity, metallothionein concentration), along with digestive enzyme activities (amylase, endocellulase) and energy reserve concentrations (glycogen, lipids), were monitored throughout the study in exposed mussels. At the Fismes and Ardre sites (downstream basin), metallic and organic contamination levels were low but still high enough to elicit AChE and GST activity induction in exposed mussels (chemical stress); besides, chemical pollutants had no apparent deleterious effects on mussel condition. At the Bouy and Sept-Saulx sites (upstream basin), mussels obviously suffered from adverse food conditions which seriously impaired individual physiological state and survival (nutritional stress); food scarcity had however no apparent effects on core biomarker responses. Digestive enzyme activities responded to both chemical and nutritional stresses, the increase in energy outputs (general adaptation syndrome-downstream sites) or the decrease in energy inputs (food scarcity-upstream sites) leading to mid- or long-term induction of digestive carbohydrase activities in exposed mussels (energy optimizing strategy). Complex regulation patterns of these activities require nevertheless the use of a multi-marker approach to allow data interpretation. Besides, their sensitivity to natural confounding environmental factors remains to be precised. PMID:22252290

  14. Scaling of Radiation Parameters of Planar and Compact Cylindrical Wire Arrays at the 1 MA Zebra Generator

    International Nuclear Information System (INIS)

    Analysis is presented on scaling of radiated x-ray power, energy and implosion timing of single planar wire arrays (SPWA), double planar wire array (DPWA), and compact cylindrical wire array (CCWA) loads (diameter is 3 and 6 mm) of Mo and W with respect to current peak (0.8-1.4 MA), mass and array dimensions at 100 ns current pulse. Such scaling investigations are important for understanding the potential of these loads as an ICF radiation source7. These data are used to identify promising directions to pursue with regard to highest x-ray output, smallest load size, and most consistent shot-to-shot performance. It is shown that W SPWA and DPWA total energy yield and peak power increased near-quadratically with current. DPWA scans of inter-planar gaps from 1.5 mm to 9 mm show an output maximum at 1.5 mm with decreasing output for 6 mm and 9 mm. A DPWA width scan shows that radiation yields decrease slowly as the width is decreased, which may allow for more compact loads without significant sacrifice to the output radiation. A mass scan of several W loads show that the implosion timing increases with mass.

  15. Presencia de Hippidion y Equus (Amerhippus (Mammalia, Perissodactyla y su distribución en el Pleistoceno superior de Chile

    Directory of Open Access Journals (Sweden)

    Frassinetti, D.

    2000-12-01

    Full Text Available Fossil remains belonging to Equidae fram Chilean localities are described and taxonomically determined. Equus (Amerhippus and Hippidion species are identified; its geographic distribution in Chile and relations with others South American Equidae are given; a Late Pleistocene age is regarded for them. Stratigraphic and paleoecological considerations are also included.Se describen y sitúan taxonómicamente los restos de équidos de las localidades chilenas. Se identifican distintas especies de Equus (Amerhippus e Hippidion, señalando su distribución geográfica y relaciones con otros équidos sudamericanos, además de referirlos al Pleistoceno superior. Se analiza su situación estratigráfica así como consideraciones de tipo paleoecológico.

  16. Applying tribology to teeth of hoofed mammals.

    Science.gov (United States)

    Schulz, Ellen; Calandra, Ivan; Kaiser, Thomas M

    2010-01-01

    Mammals inhabit all types of environments and have evolved chewing systems capable of processing a huge variety of structurally diverse food components. Surface textures of cheek teeth should thus reflect the mechanisms of wear as well as the functional traits involved. We employed surface textures parameters from ISO/DIS 25178 and scale-sensitive fractal analysis (SSFA) to quantify dental wear in herbivorous mammals at the level of an individual wear enamel facet. We evaluated cheek dentitions of two grazing ungulates: the Blue Wildebeest (Connochaetes taurinus) and the Grevy's Zebra (Equus grevyi). Both inhabit the east African grassland savanna habitat, but they belong to fundamentally different taxonomic units. We tested the hypothesis that the foregut fermenting wildebeest and the hindgut fermenting zebra show functional traits in their dentitions that relate to their specific mode of food-composition processing and digestion. In general, surface texture parameters from SSFA as well as ISO/DIS 25178 indicated that individual enamel ridges acting as crushing blades and individual wear facets of upper cheek teeth are significantly different in surface textures in the zebra when compared with the wildebeest. We interpreted the complexity and anisotropy signals to be clearly related to the brittle, dry grass component in the diet of the zebra, unlike the wildebeest, which ingests a more heterogeneous diet including fresh grass and herbs. Thus, SSFA and ISO parameters allow distinctions within the subtle dietary strategies that evolved in herbivorous ungulates with fundamentally different systematic affinities but which exploit a similar dietary niche. PMID:20949615

  17. Ocorrência de anticorpos anti-Neospora spp. em jumentos (Equus asinus) no estado de Sucre - Colômbia / Occurrence of anti-Neospora spp. Antibodies in donkeys (Equus asinus) in the state of Sucre - Colombia

    Scientific Electronic Library Online (English)

    R.D., Blanco; J.H., Patarroyo; M.I., Vargas; J.A., Cardona; L.S., Araújo; V.E., Gomez.

    2014-04-01

    Full Text Available A neosporose tem grande importância em bovinos, e sua patogênese neste hospedeiro, em termos gerais, está esclarecida, porém, em equídeos é pobremente conhecida. Na Colômbia ainda não foram reportados anticorpos Anti-Neospora spp. em equídeos, sendo assim objetivou-se no presente estudo avaliar a oc [...] orrência do parasito em jumentos (Equus asinus) de fazendas que apresentavam risco da doença nestes animais. Foram utilizados 56 animais no estado de Sucre (Colômbia), escolhidos aleatoriamente dentro das fazendas selecionadas. Utilizou-se um peptídeo recombinante originado de Neospora caninum (NcGRA1) para o diagnóstico por Dot-ELISA, e o soro foi diluído em 1:200. Este estudo reporta, pela primeira vez no estado de Sucre e na Colômbia, a presença de anticorpos anti-Neospora spp. na espécie Equus asinus, com uma ocorrência de 19,7% (11/56) dos animais amostrados. Abstract in english The neosporosis has great importance in cattle, and its pathogenesis in this host has been generally clarified, however, in horses, neosporosis is poorly known, and in Colombia anti-Neospora spp antibodies have not been reported. Therefore, the main objective in the present study was to evaluate the [...] occurrence of this parasite in donkeys (Equus asinus) from farms that presented a risk of disease in these animals, as well as no health plan for them. Were used 56 animals randomly chosen inside selected farms in the state of Sucre (Colombia). A recombinant peptide originated from Neospora caninum (NcGRA1) was used for the diagnosis with Dot-ELISA and serum was diluted 1:200. This study is the first to report the presence of anti-Neospora spp. in donkeys (Equus asinus) in the state of Sucre, and in Colombia. The occurrence was in 19.7% of the animals sampled (11/56).

  18. Perceived conflicts between pastoralism and conservation of the Kiang Equus kiang in the Ladakh Trans-Himalaya, India

    OpenAIRE

    Bhatnagar, Y. V.; Wangchuk, R.; Prins, H. H. T.; Wieren, S. E.; Mishra, C.

    2006-01-01

    An emerging conflict with Trans-Himalayan pastoral communities in Ladakh’s Changthang Plateau threatens the conservation prospects of the kiang (Equus kiang) in India. It is locally believed that Changthang’s rangelands are overstocked with kiang, resulting in forage competition with livestock. Here, we provide a review and preliminary data on the causes of this conflict. Erosion of people’s tolerance of the kiang can be attributed to factors such as the loss of traditional pastures dur...

  19. Characteristics of the herbaceous layer in preferred grazing areas of six herbivore species in the south-eastern Kruger National Park

    Directory of Open Access Journals (Sweden)

    N. van Rooyen

    1991-09-01

    Full Text Available The phytomass and species composition of the herbaceous layer in preferred grazing areas of zebra Equus burchellii, buffalo Syncerus caffer, waterbuck Kobus ellipsiprymnus, blue wildebeest Connochaetes taurinus, impala Aepyceros melampus and warthog Phacochoerusaethiopicus were investigated within the south-eastern portion of the Kruger National Park. The percentage frequency of herbaceous plants in Decreaser and Increaser categories, as determined by their reaction to different intensities of grazing, was established. The preferred grazing areas of the relevant herbivore species were compared in terms of phytomass, contribution of the Decreaser and Increaser categories, veld condition and degree of utilisation. The grazing areas of buffalo and zebra showed less utilisation than those of the other herbivore species. Warthog and impala were associated with over-utilised areas. It is clear that localised over-utilisation is an integral part of the natural grazing mosaic and should be managed as such in large African conservation areas.

  20. Dominance rank is associated with body condition in outdoor-living domestic horses (Equus caballus)

    Science.gov (United States)

    Giles, Sarah L.; Nicol, Christine J.; Harris, Patricia A.; Rands, Sean A.

    2015-01-01

    The aim of our study was to explore the association between dominance rank and body condition in outdoor group-living domestic horses, Equus caballus. Social interactions were recorded using a video camera during a feeding test, applied to 203 horses in 42 herds. Dominance rank was assigned to 194 individuals. The outcome variable body condition score (BCS) was recorded using a 9-point scale. The variables age and height were recorded and considered as potential confounders or effect modifiers. Results were analysed using multivariable linear and logistic regression techniques, controlling for herd group as a random effect. More dominant (p = 0.001) individuals generally had a higher body condition score (p = 0.001) and this association was entirely independent of age and height. In addition, a greater proportion of dominant individuals fell into the obese category (BCS ? 7/9, p = 0.005). There were more displacement encounters and a greater level of interactivity in herds that had less variation in age and height, lending strength to the hypothesis that phenotypic variation may aid cohesion in group-living species. In addition there was a strong quadratic relationship between age and dominance rank (p < 0.001), where middle-aged individuals were most likely to be dominant. These results are the first to link behavioural predictors to body condition and obesity status in horses and should prompt the future consideration of behavioural and social factors when evaluating clinical disease risk in group-living animals. PMID:25937683

  1. Interspecific communication from people to horses (Equus ferus caballus) is influenced by different horsemanship training styles.

    Science.gov (United States)

    Dorey, Nicole R; Conover, Alicia M; Udell, Monique A R

    2014-11-01

    The ability of many domesticated animals to follow human pointing gestures to locate hidden food has led to scientific debate on the relative importance of domestication and individual experience on the origins and development of this capacity. To further explore this question, we examined the influence of different prior training histories/methods on the ability of horses (Equus ferus caballus) to follow a momentary distal point. Ten horses previously trained using one of two methods (Parelli™ natural horsemanship or traditional horse training) were tested using a standard object choice task. The results show that neither group of horses was initially able to follow the momentary distal point. However, after more experience with the point, horses previously trained using the Parelli natural horsemanship method learned to follow momentary distal points significantly faster than those previously trained with traditional methods. The poor initial performance of horses on distal pointing tasks, coupled with the finding that prior training history and experimental experience can lead to success on this task, fails to support the predictions of the domestication hypothesis and instead lends support to the two-stage hypothesis. PMID:25111631

  2. Holocene extinction dynamics of Equus hydruntinus, a late-surviving European megafaunal mammal

    Science.gov (United States)

    Crees, Jennifer J.; Turvey, Samuel T.

    2014-05-01

    The European wild ass (Equus hydruntinus) is a globally extinct Eurasian equid. This species was widespread in Europe and southwest Asia during the Late Pleistocene, but its distribution became restricted to southern Europe and adjacent geographic regions in the Holocene. Previous research on E. hydruntinus has focused predominantly on its taxonomy and Late Pleistocene distribution. However, its Holocene distribution and extinction remain poorly understood, despite the fact that the European wild ass represents one of Europe's very few globally extinct Holocene megafaunal mammal species. We summarise all available Holocene zooarchaeological spatio-temporal occurrence data for the species, and analyse patterns of its distribution and extinction using point pattern analysis (kernel density estimation and Clark Evans index) and optimal linear estimation. We demonstrate that the geographic range of E. hydruntinus became highly fragmented into discrete subpopulations during the Holocene, which were associated with separate regions of open habitat and which became progressively extinct between the Neolithic and Iron Age. These data challenge previous suggestions of the late survival of E. hydruntinus into the medieval period in Spain, and instead suggest that postglacial climate-driven vegetational changes were a primary factor responsible for extinction of the species, driving isolation of small remnant subpopulations that may have been increasingly vulnerable to human exploitation. This study contributes to a more nuanced understanding of Late Quaternary species extinctions in Eurasia, suggesting that they were temporally staggered and distinct in their respective extinction trajectories.

  3. Dietary overlap among kulan Equus hemionus, goitered gazelle Gazella subgutturosa and livestock

    Directory of Open Access Journals (Sweden)

    CHU Hong-Jun

    2008-12-01

    Full Text Available We studied overlap among diets of kulan Equus hemionus, goitered gazelle Gazella subgutturosa sairensis and three domestic livestock, using micro-histological analysis of fresh fecal samples collected in the Kalamaili Ungulate Nature Reserve, Xinjiang, China during autumn and winter 2007, and spring 2008. Kulan, goitred gazelle and domestic livestock mainly ate Stipa spp., Ceratoides lateens, Artemisia spp. and white saxaul Haloxylon persicum, although plant families and species compositions of their diets differed. Pianka Niche Overlap Index C values of kulan, goitered gazelle, and 3 domestic livestock species were all over 0.8, varying from 0.832 (between goitered gazelle and domestic horse in winter to 0.986 (between kulan and domestic sheep in autumn, and between domestic horse and domestic sheep in autumn. We interpret these high overlap values as indicating serious food competition among wild animals and seasonal pastoral livestock, especially, during winters when deep snow covered ground and forage was scarce. Wild ungulates may be die due to malnutrition during those severe winters. Thus we recommend that managers of Kalamaili Ungulate Nature Reserve should set up guidelines for restricting the number of livestock entering the nature reserve in autumn, or restricting the grazing area of livestock in winter, and protecting wild ungulates in the nature reserve [Acta Zoologica Sinica 54(6?941– 954, 2008].

  4. Molecular and serological detection of Theileria equi and Babesia caballi in donkeys (Equus asinus) in Brazil.

    Science.gov (United States)

    Machado, R Z; Toledo, C Z P; Teixeira, M C A; André, M R; Freschi, C R; Sampaio, P H

    2012-05-25

    Piroplasmosis in donkeys has been recognized as a serious problem of major economic importance, since the affected animals manifest loss of appetite and decreased working capacity. The present work is aimed at detecting infection or exposure of donkeys in São Paulo, Brazil to Theileria (T.) equi and Babesia (B.) caballi using molecular and serological approaches. EDTA-blood and serum samples were collected from 88 donkeys (Equus asinus). From 88 sampled donkeys, 65 (73.86%; 95% confidence interval, PI=63.41, 82.65) and 82 (93.2%; 95% confidence interval, PI=85.75, 97.46) animals showed IgG antibodies to T. equi (by ELISA) and B. caballi (by IFAT), respectively. Twenty-eight (31.81%; 95% confidence interval, PI=22.3, 42.61) and 18 (20.45%; 95% confidence interval, PI=12.6, 30.39) donkeys were positive to T. equi and B. caballi nested PCR assays, respectively. The results indicated that T. equi and B. caballi are prevalent among donkeys in Brazil. PMID:22186194

  5. Post-conflict friendly reunion in a permanent group of horses (Equus caballus).

    Science.gov (United States)

    Cozzi, Alessandro; Sighieri, Claudio; Gazzano, Angelo; Nicol, Christine J; Baragli, Paolo

    2010-10-01

    Gregarious animals living in permanent social groups experience intra-group competition. Conflicts over resources can escalate into costly aggression and, in some conditions, non-dispersive forms of conflict resolution may be favoured. Post-conflict friendly reunions, hence reconciliation, have been described in a variety of species. The aim of this study was to explore, for the first time, the occurrence of reconciliation in a group of domestic horses (Equus caballus) and learn more about strategies used to maintain group cohesion. The behaviour of seven horses living as permanent group in an enclosure for at least 2 years was observed by video for 108h from June to August 2007. We used a Post-Conflict/Matched Control method to assess the existence of reconciliation and third-party affiliation. Behaviours recorded Post-Conflict, or during Matched Control periods, were classified as affiliative based on previous descriptions of visual communication patterns in horses. The proportion of attracted pairs over total post-conflict situations was significantly greater than the proportion of dispersed pairs, both during dyadic interactions (pconflict affiliative interactions form important social mechanisms for managing post-conflict situations in horses. PMID:20659538

  6. Evaluación clínica e histopatológica de la pitiosis cutánea en burros (Equus asinus) / Clinical and Histopathological Evaluation of Cutaneous Pythiosis in Donkeys (Equusasinus) / Avaliação clínica e histopatológica da pitiose cutânea em burros (Equus asinus)

    Scientific Electronic Library Online (English)

    José Alberto, Cardona Álvarez; Marlene Isabel, Vargas Viloria; Sandra Carolina, Perdomo Ayola.

    2013-06-01

    Full Text Available O objetivo deste estudo foi avaliar e caracterizar os aspectos clínicos e histopatológicos da pitiose cutânea em burros (Equus asinus) no Estado de Córdoba, Colômbia. Realizou-se um estudo de tipo descritivo, não probabilístico em animais de conveniência. Foram analisados nove burros com pitiose cut [...] ânea, diagnosticados clínica e histopatologicamente. Ao descrever os casos se observou uma grave ulceração granulomatose em forma de cratera com tecido necrótico, aparência tumoral, abundante exsudação pegajosa fibrinosa sanguinolenta e saída de material caseoso de cor branca amarelada denominada kunkers. As lesões se localizaram em membros, abdômen ventral e peito dos animais. Histopatologicamente, com a coloração de hematoxilina-eosina, se observou dermatite pio granulomatosa severa, com abundante infiltrado inflamatório de tipo eosinofílico e neutrofílico; com a coloração de Grocott se evidenciaram hifas com tabiques e parcialmente ramificadas em ângulo reto, de cor marrom. O diagnóstico definitivo da doença se fundamentou nas características clínicas, o diagnóstico diferencial e nos achados histopatológicos. Foi concluinte o diagnóstico da pitiose cutânea. O presente estudo se converte no primeiro relatório desta doença em burros (Equus asinus) no Estado de Córdoba na Colômbia. Abstract in spanish El objetivo de este estudio fue evaluar y caracterizar los aspectos clínicos e histopatológicos de la pitiosis cutánea en burros (Equus asinus) en el departamento de Córdoba, Colombia. Se realizó un estudio de tipo descriptivo, no probabilístico en animales de conveniencia. Fueron analizados nueve b [...] urros con pitiosis cutánea diagnosticados clínica e histopatológicamente. Al describir los casos se observó una grave ulceración granulomatosa en forma de cráter, con tejido necrótico, apariencia tumoral, abundante exudación filante fibrino-sanguinolenta y salida de material caseificado de color blanco amarillento denominado kunkers. Las lesiones se ubicaron en miembros, abdomen ventral y pecho de los animales. Histopatológicamente, con la coloración de hematoxilina-eosina, se observó dermatitis piogranulomatosa severa, con abundante infiltrado inflamatorio de tipo eosinofílico y neutrofílico; con la coloración de Grocott se evidenciaron hifas con tabiques y parcialmente ramificadas en ángulo recto, de color café. El diagnóstico definitivo de la enfermedad se fundamentó en las características clínicas, el diagnóstico diferencial y en los hallazgos histopatológicos. Fue concluyente el diagnóstico de la pitiosis cutánea. El presente estudio se convierte en el primer reporte de esta enfermedad en burros (Equus asinus) en el departamento de Córdoba y en Colombia. Abstract in english The purpose of this study was to evaluate and characterize the clinical and histopathological aspects of cutaneous pythiosis in donkeys (Equus asinus) in the Department of Cordoba, Colombia. A descriptive, non-probability study was conducted on domesticated animals. Nine donkeys clinically and histo [...] pathologically diagnosed with cutaneous pythiosis were analyzed. After describing the cases, a serious, crater-shaped granulomatous ulcer was observed, with necrotic tissue, a tumor appearance, abundant fibrinous-bloody exudation and yellowish-white caseous material known as kunkers. The lesions were found in the members, ventral abdomen and chest of the animals. Histopathologically, with the hematoxylin-eosin staining, severe pyogranulomatous dermatitis was observed, with abundant eosinophilic and neutrophilic inflammatory infiltrate; with the Grocott staining, hyphae with septa were found, partially branching into a right angle and brown in color. The definitive diagnosis of the disease was based on the clinical features, the differential diagnosis and the histopathological findings. The diagnosis of cutaneous pythiosis was conclusive. This study becomes the first report of this disease in donkeys (Equus asinus) in the department of Córdoba and in Colombi

  7. Groundwater-flow parameter estimation and quality modeling of the Equus Beds aquifer in Kansas, U.S.A.

    Science.gov (United States)

    Sophocleous, M.A.

    1984-01-01

    The salinity problems created in the Burrton area as a result of poor oil-field brine disposal practices of the past continue to be a major concern to the area depending on the Equus Beds aquifer for water, including the City of Wichita, Kansas. In this paper, an attempt is made to predict where and how fast the brine plume will move in this area, and what the average chloride concentrations in different parts of the aquifer are. In order to make such predictions, it was necessary to get a calibrated model of the groundwater-flow velocity field. Multiple regression analysis is used for parameter estimation of the steady-state groundwater-flow equation applied in the most critical area of the Equus Beds aquifer. Results of such an analysis produced a correlation coefficient of 0.992 between calculated and observed values of hydraulic head. A chloride transport modeling effort is then carried out despite some serious data deficiencies, the significance of which are evaluated through sensitivity analysis. Thus, starting with the quasi steady-state conditions of the early 1940's, it was possible to match the present chloride distribution satisfactorily. Chloride concentration predictions made for the year 2000 indicate that the quality of the Wichita well-field waters will not generally deteriorate from their present condition by that time. ?? 1984.

  8. Taxonomía y hábito alimentario de Equus conversidens (Perissodactyla, Equidae) del Pleistoceno Tardío (Rancholabreano) de Hidalgo, centro de México / Taxonomy and dietary behavior of Equus conversidens (Perissodactyla, Equidae) from the late Pleistocene (Rancholabream) of Hidalgo, central Mexico

    Scientific Electronic Library Online (English)

    Víctor M., Bravo-Cuevas; Eduardo, Jiménez-Hidalgo; Jaime, Priego-Vargas.

    2011-04-01

    Full Text Available El estudio comparado de material craneal y dental perteneciente a équidos, recuperado de sedimentos pleistocénicos innominados de origen fluvio-lacustre ubicados en la parte suroriental de Hidalgo, permitió caracterizar y asignar la muestra disponible a Equus conversidens. Este registro aporta evide [...] ncia adicional acerca de la amplia distribución que tuvo esta especie a lo largo del territorio nacional y del subcontinente Norteamericano en conjunto durante los últimos dos millones de años. Por otra parte, la interpretación del hábito alimentario mediante la implementación del método de mesodesgaste, reveló que el patrón de desgaste observado en los elementos dentales considerados en el análisis, caracterizado por una combinación de relieve oclusal bajo y cúspides romas, es estrechamente cercano al que distingue a la especie pacedora reciente Bison bison. Los resultados obtenidos indican que la población de équidos hidalguense tuvo una dieta conformada predominantemente por recursos abrasivos con un alto contenido de sílice y/o fitolitos (pastos, polvo y/o arena). El comportamiento alimentario propuesto evidencia la presencia de zonas de vegetación abierta en lo que ahora es parte del centro de México durante la segunda mitad del Pleistoceno; aunado a esto, las formas herbívoras asociadas al registro de équidos sugieren que, además de áreas donde posiblemente predominaron los pastos y otras herbáceas, también existieron zonas más arboladas, lo cual es indicativo de un hábitat heterogéneo. Abstract in english A comparative study of equid cranial and dental material, recovered from unnamed fluvio-lacustrine deposits of late Pleistocene age that crop out in southeastern Hidalgo, allowed to assign the fossil sample to Equus conversidens. The record gives additional evidence on the widespread distribution of [...] this species throughout the North American subcontinent during the last two million years. On the other hand, we evaluated the dietary behavior of this Equus population from Hidalgo by the extended mesowear analysis method. The observed mesowear pattern is comparable to that of the recent grazer species Bison bison. These species display a particular combination of low occlusal relief and blunt cusps. This suggests that the horse population from Hidalgo was a grass feeder that incoporated abrasive food items into its diet (grass and/or extrinsic grit). The results provide evidence for the existence of local grazing habitats in central Mexico during the late Pleistocene; furthermore, the associated herbivore fauna indicates wooded areas as well, thus suggesting a heterogeneous habitat.

  9. A new record of Equus (Mammalia: Equidae) from the Late Pleistocene of central-south Chile / Un nuevo registro de Equus (Mammalia: Equidae) para el Pleistoceno Superior de Osorno, Chile

    Scientific Electronic Library Online (English)

    OMAR P, RECABARREN; MARIO, PINO; INÉS, CID.

    2011-12-01

    Full Text Available Se analizan e interpretan 14 fósiles correspondientes a dientes y huesos de caballo registrados en el sitio Pilauco, Osorno (40°39' S-73°07' W). El sitio se formó asociado a un pantano en un borde del antiguo río Damas; en él se ha conservado abundante material de mastofauna y flora pleistocénica. U [...] na fecha radiocarbónica de 11457 ± 140 A.P obtenida de un molar, es concordante con el modelo de edad del sitio. La identificación taxonómica permite asociar a los fósiles a la especie Equus (Amerhippus) andium, lo que confirma la presencia de la especie en el centro-sur de Chile. Por otra parte, la posición geográfica de los hallazgos y la reconstrucción del paisaje indicarían que se trata de ejemplares cuyas adaptaciones en los metapodios son concordantes para el paisaje pleistocénico de Pilauco dominado por suelos volcánicos blandos, con presencia de bosquetes dispersos en grandes extensiones de praderas de gramíneas. Abstract in english Fourteen dental and bone parts of a horse excavated from the Pilauco paleontological site, Osorno (40°39' S-73°07' W) are analysed and interpreted. This site was formed in association with a peat bog located on the banks of the old Damas River and has conserved abundant late Pleistocene mammalian fa [...] una and flora materials. A date of 11457 ± 140 14C yrs B.P. was obtained from a molar and agrees with our stratigraphic age model. We have identified the fossils as pertaining to the species Equus (Amerhippus) andium, which confirms its presence in central-south Chile. Furthermore, the recorded geographic location indicate that the metapodial adaptations of the specimens previously described agree with the reconstructed late Pleistocene landscape of Pilauco, dominated by soft volcanic soils and isolated forest patches over large extensions of grasslands.

  10. A new record of Equus (Mammalia: Equidae from the Late Pleistocene of central-south Chile Un nuevo registro de Equus (Mammalia: Equidae para el Pleistoceno Superior de Osorno, Chile

    Directory of Open Access Journals (Sweden)

    OMAR P RECABARREN

    2011-12-01

    Full Text Available Fourteen dental and bone parts of a horse excavated from the Pilauco paleontological site, Osorno (40°39' S-73°07' W are analysed and interpreted. This site was formed in association with a peat bog located on the banks of the old Damas River and has conserved abundant late Pleistocene mammalian fauna and flora materials. A date of 11457 ± 140 14C yrs B.P. was obtained from a molar and agrees with our stratigraphic age model. We have identified the fossils as pertaining to the species Equus (Amerhippus andium, which confirms its presence in central-south Chile. Furthermore, the recorded geographic location indicate that the metapodial adaptations of the specimens previously described agree with the reconstructed late Pleistocene landscape of Pilauco, dominated by soft volcanic soils and isolated forest patches over large extensions of grasslands.Se analizan e interpretan 14 fósiles correspondientes a dientes y huesos de caballo registrados en el sitio Pilauco, Osorno (40°39' S-73°07' W. El sitio se formó asociado a un pantano en un borde del antiguo río Damas; en él se ha conservado abundante material de mastofauna y flora pleistocénica. Una fecha radiocarbónica de 11457 ± 140 A.P obtenida de un molar, es concordante con el modelo de edad del sitio. La identificación taxonómica permite asociar a los fósiles a la especie Equus (Amerhippus andium, lo que confirma la presencia de la especie en el centro-sur de Chile. Por otra parte, la posición geográfica de los hallazgos y la reconstrucción del paisaje indicarían que se trata de ejemplares cuyas adaptaciones en los metapodios son concordantes para el paisaje pleistocénico de Pilauco dominado por suelos volcánicos blandos, con presencia de bosquetes dispersos en grandes extensiones de praderas de gramíneas.

  11. Painting stripes on a horse does not make it a zebra : The present and potential future of the International Court of Justice

    OpenAIRE

    Karlsson, Fredrik

    2009-01-01

      Upon a closer examination of the role and performance of the International Court of Justice, we find that it does primarily fulfil its role and obligation as far as the UN charter and the Courts stature are concerned. It is upon the application of Kjell Goldmann’s Internationalists Programme that we find ourselves wanting more from the Court. If we assume the development of international institutions, exchange, communication and the like to be desirable and necessary for the continued de...

  12. New retinoid X receptor subtypes in zebra fish (Danio rerio) differentially modulate transcription and do not bind 9-cis retinoic acid.

    OpenAIRE

    Jones, B B; Ohno, C K; Allenby, G; Boffa, M B; Levin, A A; Grippo, J. F.; Petkovich, M

    1995-01-01

    Retinoid X receptors (RXRs), along with retinoic acid (RA) receptors (RARs), mediate the effects of RA on gene expression. Three subtypes of RXRs (alpha, beta, and gamma) which bind to and are activated by the 9-cis stereoisomer of RA have been characterized. They activate gene transcription by binding to specific sites on DNA as homodimers or as heterodimers with RARs and other related nuclear receptors, including the vitamin D receptor, thyroid hormone receptors (TRs), and peroxisome prolif...

  13. Radiative properties of asymmetric and symmetric X-pinches with two and four wires recently produced on the UNR 1 MA Zebra generator

    International Nuclear Information System (INIS)

    Experimental results of studies of the 1 MA X-pinch X-ray source in a wide spectral region are overviewed. Implosion dynamics and radiative properties of various X-pinches were studied by spatially and time-resolved X-ray and optical diagnostics. In particular, dynamics of spatial and temporal developments of the structure of X-ray emitting regions (1-5 keV), temporal characteristics of X-ray pulses, X-ray radiation outputs and electron beam characteristics from symmetric and asymmetric Mo, Cu, and combined asymmetric Mo/W X-pinches with two or four wires were studied. The mechanisms of X-ray multiburst generation are discussed. The future applications of the high-current X-pinch as a 5-10 kJ sub-keV-10 keV radiation driver are considered

  14. POST-HATCH ORAL ESTROGEN EXPOSURE IMPAIRS ADULT REPRODUCTIVE PERFORMANCE OF ZEBRA FINCH IN A SEX-SPECIFIC MANNER. (R825294)

    Science.gov (United States)

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  15. Metabolic programming of zebra fish, Danio rerio, uncovered; physiological performance as explained by Dynamic Energy Budget theory and life cycle consequences of uranium induced perturbations.

    OpenAIRE

    Augustine, Starrlight

    2012-01-01

    L'objectif de ces travaux de thèse était de caractériser la toxicité de l'uranium sur le métabolisme du poisson zèbre, Danio rerio. Puisque les effets de l'uranium se traduisent par des modifications de la performance du métabolisme, la question suivante se pose: que savons-nous du métabolisme du poisson zèbre témoin? Très peu de chose. En effet, nos connaissances à ce sujet sont assez limitées en dépit d'un grand nombre de travaux sur le développement de ce poisson. C'est pour...

  16. From Aardvark to Zebra: A New Millennium Analysis of Theory Development in Public Relations Academic Journals. A Top Faculty/Student Research Paper.

    Science.gov (United States)

    Sallot, Lynne M.; Lyon, Lisa J.; Acosta-Alzuru, Carolina; Jones, Karyn Ogata

    In a replication and extension of a 1984 study by M. A. Ferguson to investigate the status of theory building by public relations scholars, 748 abstracts and/or articles published in "Public Relations Review,""Journal of Public Relations Research," and its predecessor "Public Relations Research Annual," since their inceptions through the year…

  17. Testing of five methods for the control of zebra mussels in cooling circuits of power plants located on the Moselle river

    International Nuclear Information System (INIS)

    Bioassays have been conducted on site at the Cattenom nuclear power plant located on the Moselle River (in northeast France) to control mussels in auxiliary plant circuits. During the course of a two-year program, five methods were tested: - thermal treatment (33 deg to 40 deg C), - high dosage chlorination (> 50 ppm), - low dosage chlorine dioxide, - potassium salt (KCI > 100 ppm), - one organic compound (Mexel 432). This note presents a comparison of the treatments shown to be most effective, on the basis of technical feasibility, cost and environmental acceptability. (author). 8 figs., 10 refs., 3 tabs

  18. Radio continua modulated by waves: Zebra patterns in solar and pulsar radio spectra?n in the 2001 June 15 flare.

    Czech Academy of Sciences Publication Activity Database

    Karlický, Marian

    2013-01-01

    Ro?. 552, April (2013), A90/1-A90/6. ISSN 0004-6361 R&D Projects: GA ?R GAP209/12/0103 Grant ostatní: EU(XE) PIRSES-GA-2011-295272 Institutional support: RVO:67985815 Keywords : Sun * radio radiation * pulsars Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 4.479, year: 2013

  19. Adult neuron addition to the zebra finch song motor pathway correlates with the rate and extent of recovery from botox-induced paralysis of the vocal muscles

    OpenAIRE

    Pytte, Carolyn; Yu, Yi-Lo; Wildstein, Sara; George, Shanu; Kirn, John

    2011-01-01

    In adult songbirds, neurons are continually incorporated into the telencephalic nucleus HVC, a pre-motor region necessary for the production of learned vocalizations. Previous studies have demonstrated that neuron addition to HVC is highest when song is most variable: in juveniles during song learning, in seasonally singing adults during peaks in plasticity that precede the production of new song components, or during seasonal re-establishment of a previously learned song. These findings sugg...

  20. Young and intense: FoxP2 immunoreactivity in Area X varies with age, song stereotypy, and singing in male zebra finches

    Directory of Open Access Journals (Sweden)

    ChristopherKirkThompson

    2013-02-01

    Full Text Available FOXP2 is a transcription factor functionally relevant for learned vocalizations in humans and songbirds. In songbirds, FoxP2 mRNA expression in the medium spiny neurons of the basal ganglia song nucleus Area X is developmentally regulated and varies with singing conditions in different social contexts. How individual neurons in Area X change FoxP2 expression across development and in social contexts is not known, however. Here we address this critical gap in our understanding of FoxP2 as a link between neuronal networks and behavior. We used a statistically unbiased analysis of FoxP2-immunoreactivity (IR on a neuron-by-neuron basis and found a bimodal distribution of FoxP2-IR neurons in Area X: weakly-stained and intensely-stained. The density of intensely-stained FoxP2-IR neurons was 10 times higher in juveniles than in adults, exponentially decreased with age, and was negatively correlated with adult song stability. Three-week old neurons labeled with BrdU were more than five times as likely to be intensely-stained than weakly-stained. The density of FoxP2-IR putative migratory neurons with fusiform-shaped nuclei substantially decreased as birds aged. The density of intensely-stained FoxP2-IR neurons was not affected by singing whereas the density of weakly-stained FoxP2-IR neurons was. Together, these data indicate that young Area X medium spiny neurons express FoxP2 at high levels and decrease expression as they become integrated into existing neural circuits. Once integrated, levels of FoxP2 expression correlate with singing behavior. Together, these findings raise the possibility that FoxP2 levels may orchestrate song learning and song stereotypy in adults by a common mechanism.

  1. Utilization of Polyclonal Antibodies Produced in local horses (Equus caballus) AS A resource for development OF ELISA Conjugate to Detect Hepatitis B Virus (HBV) Surface AntigenS

    OpenAIRE

    E. Yulianti; S.N. Depamede; M. Sriasih

    2012-01-01

    The aim of this study was to utilize the antibody produced using Indonesia local horses (Equus caballus) to make the conjugate of ELISA kit for detection of hepatitis B virus (HBV) surface antigen (HBsAg). The polyclonal antibodies were isolated and purified from local horses immunized repeatedly using isolated and purified HBsAg from Indonesia. The antibodies were conjugated with horseradish peroxidase by a modified method of Nakane and Kawaoi. The conjugate activities were performed using t...

  2. First evidence of Equus asinus L. in the Chalcolithic disputes the Phoenicians as the first to introduce donkeys into the Iberian Peninsula

    DEFF Research Database (Denmark)

    Cardoso, João L.; Vilstrup, Julia T

    2013-01-01

    Two equid species have been documented in the Pleistocene of the Iberian Peninsula, the horse Equus caballus, and the Eurasian hemione Equus hydruntinus. While the former survived the Holocene–Pleistocene until now, the timing for the extinction of the latter is unclear. Scarce, fragmented archaeological remains assess the presence of small equids living in the Holocene of Iberia. Those could possibly correspond to the Eurasian hemione although unambiguous morphological identification is often not possible. With the find of an equid tooth from Leceia, a Chalcolithic fortified site in Portugal, and using both morphological and mitochondrial genome analyses, we demonstrate for the first time the presence of a new equid species in Holocene Iberia, namely a donkey (Equus asinus). Radiocarbon dating of the tooth to Cal 2340–2130, and 2080–2060 BC with 95% probability, demonstrates that donkeys were present in Iberia well before the arrival of Phoenicians in the first quarter of the first millennium BC (900–750 years BC), which were considered so far as the first who introduced donkeys in the region.

  3. Baseline data-collection and quality-control protocols and procedures for the Equus beds ground-water recharge demonstration project near Wichita, Kansas, 1995-96

    Science.gov (United States)

    Ziegler, A.C.; Combs, L.J.

    1997-01-01

    The Equus Beds Ground-Water Recharge Demonstration Project is being conducted from 1995 through 1999 as part of the High Plains States Groundwater Recharge Demonstration Program to determine if recharge of the Equus beds aquifer in south-central Kansas is a viable alternative in meeting the increased demands for water in this rapidly growing part of the State. As part of the demonstration project, protocols and procedures were developed for the collection of baseline hydrologic and water-quality data from September 1995 through September 1996 and are described in this report. During this initial phase of the demonstration project, 33 data-collection sites were identified and instrumented, and an aquifer test at one site was conducted to determine transmissivity, specific yield, hydraulic conductivity, and riverbed conductance of the Equus beds aquifer in the area northwest of Wichita, Kansas. Selected water-quality samples were analyzed for as many as 340 chemical constituents to determine the baseline or ambient concentrations of inorganic and orgainc constituents.

  4. Speciation with gene flow in equids despite extensive chromosomal plasticity

    DEFF Research Database (Denmark)

    Jónsson, Hákon; Schubert, Mikkel

    2014-01-01

    Horses, asses, and zebras belong to a single genus, Equus, which emerged 4.0-4.5 Mya. Although the equine fossil record represents a textbook example of evolution, the succession of events that gave rise to the diversity of species existing today remains unclear. Here we present six genomes from each living species of asses and zebras. This completes the set of genomes available for all extant species in the genus, which was hitherto represented only by the horse and the domestic donkey. In addition, we used a museum specimen to characterize the genome of the quagga zebra, which was driven to extinction in the early 1900s. We scan the genomes for lineage-specific adaptations and identify 48 genes that have evolved under positive selection and are involved in olfaction, immune response, development, locomotion, and behavior. Our extensive genome dataset reveals a highly dynamic demographic history with synchronous expansions and collapses on different continents during the last 400 ky after major climatic events. We show that the earliest speciation occurred with gene flow in Northern America, and that the ancestor of present-day asses and zebras dispersed into the Old World 2.1-3.4 Mya. Strikingly, we also find evidence for gene flow involving three contemporary equine species despite chromosomal numbers varying from 16 pairs to 31 pairs. These findings challenge the claim that the accumulation of chromosomal rearrangements drive complete reproductive isolation, and promote equids as a fundamental model for understanding the interplay between chromosomal structure, gene flow, and, ultimately, speciation.

  5. Female major histocompatibility complex type affects male testosterone levels and sperm number in the horse (Equus caballus).

    Science.gov (United States)

    Burger, D; Dolivo, G; Marti, E; Sieme, H; Wedekind, C

    2015-05-22

    Odours of vertebrates often contain information about the major histocompatibility complex (MHC), and are used in kin recognition, mate choice or female investment in pregnancy. It is, however, still unclear whether MHC-linked signals can also affect male reproductive strategies. We used horses (Equus caballus) to study this question under experimental conditions. Twelve stallions were individually exposed either to an unfamiliar MHC-similar mare and then to an unfamiliar MHC-dissimilar mare, or vice versa. Each exposure lasted over a period of four weeks. Peripheral blood testosterone levels were determined weekly. Three ejaculates each were collected in the week after exposure to both mares (i.e. in the ninth week) to determine mean sperm number and sperm velocity. We found high testosterone levels when stallions were kept close to MHC-dissimilar mares and significantly lower ones when kept close to MHC-similar mares. Mean sperm number per ejaculate (but not sperm velocity) was positively correlated to mean testosterone levels and also affected by the order of presentation of mares: sperm numbers were higher if MHC-dissimilar mares were presented last than if MHC-similar mares were presented last. We conclude that MHC-linked signals influence testosterone secretion and semen characteristics, two indicators of male reproductive strategies. PMID:25904670

  6. Retrospective serological investigation of bovine tuberculosis in two gemsbok (Oryx gazelle gazelle) and an onager (Equus hemionus onager).

    Science.gov (United States)

    Schaftenaar, Willem; Lécu, Alex; Greenwald, Rena; Lyashchenko, Konstantin P

    2013-12-01

    In 1997 a 26-yr-old gemsbok (Oryx gazelle gazelle) died of bovine tuberculosis in a zoo. Three remaining gemsbok were administered the comparative tuberculin skin test repeatedly over a period of 5 mo. Two animals showed inconclusive results on the second test. All three gemsbok were euthanatized. Mycobacterium bovis was isolated from one of those with an inconclusive skin test result, whereas Mycobacterium fortuitum was detected in the other gemsbok. Eight years later, an onager (Equus hemionus onager) died of bovine tuberculosis. This animal had been kept in the same building as the gemsbok. Three herd mates were culled after administering the comparative tuberculin skin test. They were all nonreactors and produced no evidence of tuberculosis at postmortem examination. Retrospectively, using plasma samples collected from the gemsbok and onagers, three antibody tests, Elephant TB STAT-PAK, multiantigen print immunoassay (MAPIA), and dual-path platform (DPP) VetTB (Chembio Diagnostic Systems Inc., Medford, New York, 11763, USA), were used to assess their diagnostic value for these species. The M. bovis-infected gemsbok tested strongly positive by Elephant TB STAT-PAK at the time of euthanasia and 5 mo earlier when the skin test was negative. This animal was not antibody reactive in MAPIA and DPP VetTB. No M. bovis-specific antibody was detected in the other two gemsboks by any of the immunoassays. Among the onagers, Elephant TB STAT-PAK, MAPIA, and DPP VetTB revealed gradually increasing antibody response in the animal that died of bovine tuberculosis, but not in the three disease-free herd mates euthanatized. Seroconversion in the M. bovis-infected onager was first noticed 5 yr before death when the tuberculin skin test was negative. PMID:24450065

  7. Perceived conflicts between pastoralism and conservation of the kiang Equus kiang in the Ladakh Trans-Himalaya, India.

    Science.gov (United States)

    Bhatnagar, Yash Veer; Wangchuk, Rinchen; Prins, Herbert H T; Van Wieren, Sipke E; Mishra, Charudutt

    2006-12-01

    An emerging conflict with Trans-Himalayan pastoral communities in Ladakh's Changthang Plateau threatens the conservation prospects of the kiang (Equus kiang) in India. It is locally believed that Changthang's rangelands are overstocked with kiang, resulting in forage competition with livestock. Here, we provide a review and preliminary data on the causes of this conflict. Erosion of people's tolerance of the kiang can be attributed to factors such as the loss of traditional pastures during an Indo-Chinese war fought in 1962, immigration of refugees from Tibet, doubling of the livestock population in about 20 years, and increasing commercialization of cashmere (pashmina) production. The perception of kiang overstocking appears misplaced, because our range-wide density estimate of 0.24 kiang km(-2) (+/- 0.44, 95% CL) is comparable to kiang densities reported from Tibet. A catastrophic decline during the war and subsequent recovery of the kiang population apparently led to the overstocking perception in Ladakh. In the Hanle Valley, an important area for the kiang, its density was higher (0.56 km(-2)) although even here, we estimated the total forage consumed by kiang to be only 3-4% compared to 96-97% consumed by the large livestock population (78 km(-2)). Our analysis nevertheless suggests that at a localized scale, some herders do face serious forage competition from kiang in key areas such as moist sedge meadows, and thus management strategies also need to be devised at this scale. In-depth socioeconomic surveys are needed to understand the full extent of the conflicts, and herder-centered participatory resolution needs to be facilitated to ensure that a sustainable solution for livelihoods and kiang conservation is achieved. PMID:16955231

  8. A useful marking method for free living mammals

    Directory of Open Access Journals (Sweden)

    E. Young

    1971-05-01

    Full Text Available A paint-spraying device was employed for marking wild African mammals without capture. This relatively inexpensive marking technique, which had originally been used for the marking of American desert bighorn sheep at drinking places, was also successfully applied in the marking of impala, Aepyceros melampus, blue wildebeest, Connochaetes taurinus, Burchell's zebra, Equus burchellii antiquorum aud the African elephant, Loxodonta africana. The apparatus used differs in some respects from that originally described by Hanson (1964. It was also used for the marking of animals from a mobile unit and away from fixed drinking places. This paper is based on a part of a thesis, submitted to the University of Pretoria in partial fulfilment of the requirements for the degree of D.Sc. (Wildlife Management.

  9. Spotted hyaenas Crocuta crocuta prey on new-born elephant calves in Hwange National Park, Zimbabwe

    Directory of Open Access Journals (Sweden)

    Julia Salnicki

    2001-08-01

    Full Text Available Spotted hyaena Crocuta crocuta are known to be opportunists and to have a varied diet including mammals, reptiles and birds. Prey most often hunted are medium sized ungulates but spotted hyaenas will on occasion take larger species such as giraffe Giraffa camelopardalis and zebra Equus burchellii. They are also known to hunt whichever species are most abundant and will vary their prey seasonally. In this study spotted hyaenas were observed to take an unusual prey species in the form of elephant calves (Loxodonta africana. On a number of occasions hyaenas were observed feeding on or killing newborn and very young elephant calves. These observations were made whilst the authors were conducting research on spotted hyaena ecology in the woodlands of Hwange National Park, Zimbabwe and were made during the dry season between September and November 1999.

  10. Trypanosoma brucei Infection in asymptomatic greater Kudus (Tragelaphus strepsiceros) on a game ranch in Zambia.

    Science.gov (United States)

    Munang'andu, Hetron Mweemba; Siamudaala, Victor; Munyeme, Musso; Nambota, Andrew; Mutoloki, Stephen; Matandiko, Wigganson

    2010-03-01

    Trypomastogotes of Trypanosoma brucei were detected from 4 asymptomatic kudus (Tragelaphus strepsiceros) on a game ranch located approximately 45 km north east of Lusaka, Zambia. Blood smears examined from 14 wildlife species comprising of the impala (Aepyceros melampus), Kafue lechwe (kobus leche kafuensis), sable antelope (Hippotragus niger), tsessebe (Damaliscus lunatus), warthog (Phacochoerus aethiopicus), puku (Kobus vardoni), zebra (Equus burchelli), waterbuck (Kobus ellipsiprymnus), bushbuck (Tragelaphus scriptus), reedbuck (Redunca arundinum), wilderbeest (Connochaetes taurinus), hartebeest (Alcephelus lichtensteini), African buffalo (Syncerus caffer), and kudu (Tragelaphus strepsiceros) showed that only the kudu had T. brucei. Although game ranching has emerged to be a successful ex-situ conservation strategy aimed at saving the declining wildlife population in the National Parks, our findings suggest that it has the potential of aiding the re-distribution of animal diseases. Hence, there is a need for augmenting wildlife conservation with disease control strategies aimed at reducing the risk of disease transmission between wildlife and domestic animals. PMID:20333288

  11. Surveillance and control of anthrax and rabies in wild herbivores and carnivores in Namibia.

    Science.gov (United States)

    Berry, H H

    1993-03-01

    Anthrax has been studied intensively in Etosha National Park, Namibia since 1966; in addition, since 1975, mortality due to rabies and all other causes has been recorded, totalling 6,190 deaths. Standard diagnostic procedures demonstrated that at least 811 deaths (13%) were due to anthrax and 115 deaths (2%) were caused by rabies. Of the total number of deaths due to anthrax, 97% occurred in zebra (Equus burchelli), elephant (Loxodonta africana), wildebeest (Connochaetes taurinus) and springbok (Antidorcas marsupialis) while 96% of rabies deaths occurred in kudu (Tragelaphus strepsiceros), jackal (Canis mesomelas), bat-eared fox (Otocyon megalotis) and lion (Panthera leo). Anthrax deaths were highest in the rainy season for zebra, wildebeest and springbok, while elephant mortality peaked during dry seasons. No statistical relationship existed between seasonal rainfall and overall incidence of either anthrax or rabies. Control of anthrax is limited to prophylactic inoculation when rare or endangered species are threatened. Incineration of anthrax carcasses and chemical disinfection of drinking water are not feasible at Etosha. Rabies control consists of the destruction of rabid animals and incineration of their carcasses when possible. PMID:8518440

  12. Sarcoide equino fibroblástico periocular en un burro (Eqqus asinus) / Periocular fibroblastic sarcoid in a donkey (Equus asinus ) / Sarcóide equino fibroblástico periocular em um burro (Eqqus asinus)

    Scientific Electronic Library Online (English)

    José, Cardona Álvarez; Marlene, Vargas Viloria; Sandra, Perdomo Ayola.

    2013-01-01

    Full Text Available Este estudo pretende descrever e discutir os signos clínicos, as lesões macro e microscópicas, a epidemiologia e o método diagnostico num caso de Sarcoide Fibroblastico Periocular num jumento (Eqqus asinus), no departamento de Córdoba, no noroeste da Colômbia. Ao abordar o caso clínico, observaram-s [...] e múltiplas massas nodulares na parte superior e inferior das pálpebras e no ângulo ocular medial do lado esquerdo, com uma discreta ulceração e levantamento difuso da pele caracterizado por uma aparência tumoral, granulomatosa, de consistência firme e fibrosa. Os encontros histopatológicos demonstraram hiperplasia epidérmica, hiperqueratose, projeções epiteliais longas em direção à derme e orientação perpendicular dos fibroblastos em relação à membrana basal. O diagnostico fundamentou-se nas características clínicas, epidemiológicas e nos encontros histopatológicos. Abstract in spanish En el presente estudio se describen y discuten los signos clínicos, lesiones macro y microscópicas, epidemiología y el método diagnóstico de un caso de Sarcoide Fibroblastico Periocular en burros (Equus asinus) en el departamento de Córdoba (Colombia). El animal presentó múltiples masas nodulares en [...] la parte superior e inferior de los párpados y el ángulo ocular medial del lado izquierdo, con discreta ulceración y levantamiento difuso de la piel, caracterizadas por una apariencia tumoral, granulomatosa, de consistencia firme y fibrosa. Los hallazgos histopatológicos mostraron hiperplasia epidérmica, hiperqueratosis, largas proyecciones epiteliales en dirección a la dermis y orientación perpendicular de los fibroblastos en relación a la membrana basal. El diagnóstico se fundamentó en las características clínicas, epidemiológicas, y en los hallazgos histopatológicos. Abstract in english In the present study we describe and discuss the clinical signs, gross and microscopic lesions, epidemiology, and diagnosis of a periocular fibroblastic sarcoid case in a donkey (Equus asinus) in Cordoba province (Colombia). The animal presented multiple nodular masses in the upper and lower eyelids [...] and the medial angle of the left eye, with slight ulceration and diffuse skin lifting, characterized by tumor-like appearance, granulomatous, firm, and fibrous. Histopathological findings included epidermal hyperplasia, hyperkeratosis, long epithelial projections toward the dermis, and perpendicular orientation of fibroblasts relative to the basal membrane. The diagnosis was based on the clinical, epidemiological, and pathological findings.

  13. The Culture of Sound: A Case Study of Birdsong Competition in Chana District, Thailand

    OpenAIRE

    Aphichet Kirichot; Sopee Untaya; Supachai Singyabuth

    2014-01-01

    Southeast Asian birdsong competitions are vital to the makeup of the Southern Thai economy. This is a qualitative research that uses observation, interview and document study to examine the zebra dove culture of Chana District in Songkhla Province. The research results show that vocal zebra dove competitions stimulate and drive the economy and society of Chana District. Zebra dove breeding is a large and lucrative occupation in the area that has spawned a number of supplementary professions, ...

  14. Absence of population asymmetry in the American Quarter Horse (Equus ferus caballus) performing skilled left and right manoeuvres in reining competition.

    Science.gov (United States)

    Whishaw, Ian Q

    2015-09-01

    Use of the right hand by humans for speech-related hand gestures, writing and throwing exemplifies motoric asymmetry. There are reports of asymmetry in many other animal species, including reports of left preference in emotional responsivity, spontaneous behaviour and the trained performance of the horse, Equus ferus caballus. The present study used the novel approach of using judges' scores to examine asymmetry in an equestrian event. The study analysed the scores of five judges evaluating the reining performance of 482, three-year-old American Quarter Horses competing in a major competition. Reining requires that the horses perform the manoeuvres of spin, circle and stop directed to either the left or right and symmetrical performance is featured in the judging criteria. The scores were sensitive to performance level, sex and manoeuvre, but there was no evidence of a population asymmetry in the left vs. right direction of the manoeuvres. The results are discussed in relation to need of using a large number of subjects in measuring asymmetry, the expression of individual vs. population asymmetry as a function of morphological and behavioural measures, and the influence of behavioural training on asymmetry. PMID:25861972

  15. Võrguäri Eestis kiratseb / Indrek Kald

    Index Scriptorium Estoniae

    Kald, Indrek, 1974-

    2004-01-01

    Autor otsib põhjusi, miks tänavuse Interneti-kaupluste edetabeli koostamiseks saatis oma äritulemused vaid viis võrgukauplust. Zebra Infosüsteemide tegevjuhi Peeter Tamme arvamus e-äri kiratsemise põhjuste kohta

  16. Toxico-kinetic, chemical and radiological toxicity of uranium on zebra fish (Danio rerio); Toxicocinetique, toxicite chimique et radiologique de l'uranium chez le poisson zebre (Danio rerio)

    Energy Technology Data Exchange (ETDEWEB)

    Barillet, S

    2007-06-15

    This thesis explores the toxico-kinetic and toxicological aspects of uranium in fish. Uranium, appears to be highly bio accumulated and bio concentrated in fish. It spreads all through the whole organism. Nevertheless, its distribution is heterogeneous (gills and liver being the main sites of accumulation).From a toxicological point of view, we notice perturbations of the antioxidant system (inhibitions of hepatic Sod, Cat and G Px activities; depletion of total GSH) and of the cholinergic system (inhibition/over-activation of brain AChE). Genotoxic effects also appear in red blood cells, hepatocytes and gonad cells. The kinetics of these biochemical perturbations depend on the radiological activity of uranium, responses appearing earlier with increasing delivered activity. Histological effects (differing in types depending on delivered radiological activity) are also observed (in gills and muscles). (author)

  17. Time budget-, behavioral synchrony- and body score development of a newly released Przewalski’s horse group Equus ferus przewalskii, in the Great Gobi B Strictly Protected Area in SW Mongolia

    OpenAIRE

    Souris, Anne-Camille; Kaczensky, Petra; Julliard, Romain; Walzer, Christian

    2007-01-01

    The Przewalski’s horse (Equus ferus przewalskii) became extinct in the wild in the 1960s, but survived as a species due to captive breeding. There have been several initiatives to re-introduce the species in central Asia, but until now only two projects in Mongolia establish free-ranging populations. Data on basic ecology and behavior of the species prior to extinction is largely lacking and a good documentation of the re-introduction process is essential. Between 13 May and 2 September 200...

  18. Characterization of a Full-Length Endogenous Beta-Retrovirus, EqERV-Beta1, in the Genome of the Horse (Equus caballus

    Directory of Open Access Journals (Sweden)

    Antoinette C. van der Kuyl

    2011-06-01

    Full Text Available Information on endogenous retroviruses fixed in the horse (Equus caballus genome is scarce. The recent availability of a draft sequence of the horse genome enables the detection of such integrated viruses by similarity search. Using translated nucleotide fragments from gamma-, beta-, and delta-retroviral genera for initial searches, a full-length beta-retrovirus genome was retrieved from a horse chromosome 5 contig. The provirus, tentatively named EqERV-beta1 (for the first equine endogenous beta-retrovirus, was 10434 nucleotide (nt in length with the usual retroviral genome structure of 5’LTR-gag-pro-pol-env-3’LTR. The LTRs were 1361 nt long, and differed approximately 1% from each other, suggestive of a relatively recent integration. Coding sequences for gag, pro and pol were present in three different reading-frames, as common for beta-retroviruses, and the reading frames were completely open, except that the env gene was interrupted by a single stopcodon. No reading frame was apparent downstream of the env gene, suggesting that EqERV-beta1 does not encode a superantigen like mouse mammary tumor virus (MMTV. A second proviral genome of EqERV-beta1, with no stopcodon in env, is additionally integrated on chromosome 5 downstream of the first virus. Single EqERV-beta1 LTRs were abundantly present on all chromosomes except chromosome 24. Phylogenetically, EqERV-beta1 most closely resembles an unclassified retroviral sequence from cattle (Bos taurus, and the murine beta-retrovirus MMTV.

  19. INLUÊNCIA DO TEMPO DE DESCANSO “ANTE MORTEM” E DIETA DE MELAÇO SOBRE OS NÍVEIS DE GLICOGÊNIO MUSCULAR NA CARNE DE EQÜINOS (Equus caballus INFLUENCE OF “ANTE MORTEM” RESTING TIME AND MOLASSES DIET UPON MUSCULAR GLYCOGEN LEVELS IN EQUINES MEAT (Equus caballus

    Directory of Open Access Journals (Sweden)

    César Augusto Garcia

    2007-09-01

    Full Text Available

    Foram coletadas 48 amostras de músculos tríceps braquial e bíceps femural de vinte e quatro eqüinos machos, sem raça definida, adultos e com pesos aproximadamente iguais. Antes do abate, os animais foram divididos em seis lotes que tiveram descanso ante mortem de zero, seis, quatorze, dezoito e vinte e quatro horas respectivamente. O lote de animais que descansou por dezoito horas foi subdividido em dois sublotes, sendo que um deles recebeu dieta de solução aquosa a 5% de melaço. Todos os outros animais só receberam água e ficaram em jejum. Não se observou influência sobre o pH. O glicogênio foi dosado pelos métodos de Pfluger e Nelson. O lote que apresentou menores índices de glicogênio foi o que descansou por zero hora, enquanto que o lote que apresentou maiores índices de glicogênio foi o que descansou por vinte e quatro horas.

    Influence of “ante mortem” resting time and molasses diet upon muscular glycogen levels in equines meat (Equus caballus were studied. Forty-eight samples of triceps brachial and biceps femoral muscles of twenty-four adults and hybrids equines with approximately the same weights were analyzed. The animals were divided before death, in six groups with “ante mortem” resting time of zero, six, fourteen, eighteen and twenty-four hours, respectively. The animal groups with eighteen hours of rest were divided in two sub-groups and one received water solution with 5% of molasses. Alteration in pH levels were not observed. The glycogen was measured by Pfluger and Nelson’s methods. The group with smaller glycogen level was the group with zero hour of “ante mortem” rest, while the group with higher glycogen levels was the group with twenty-four hours of rest.

  20. INFLUÊNCIA DO TEMPO DE DESCANÇO "ANTE-MORTEM" E DIETA DE MELAÇO NOS ÍNDICES DE pH DA CARNE DE EQÜINOS (Equus caballus INFLUENCE OF “ANTE-MORTEM” RESTING TIME AND MOLASSES DIET UPON pH LEVELS OF EQUINES MEAT (Equus caballus

    Directory of Open Access Journals (Sweden)

    César Augusto Garcia

    2007-09-01

    Full Text Available

    Foram mensuradas as concentrações de pH de 24 eqüinos adultos, machos e de pesos aproximadamente iguais. Dividiu-se os animais em 5 lotes com 4 animais cada um, com exceção do lote no 4 que foi subdividido em sublote 4A e sublote 4B com 4 animais cada um deles. Todos os animais receberam jejum e dieta hídrica, com exceção do lote no 4B que recebeu solução aquosa a 5% de melaço, para observar se influiria nas concentrações de pH. Cada lote foi submetido a um tempo de descanso ante-mortem diferente, sendo zero hora de descanso para o lote no 1, seis horas de descanso para o lote no 2, quatorze, dezoito e vinte e quatro horas de descanso ante mortem para os lotes No 3, 4A, 4B e 5, respectivamente. Os menores valores de pH foram observados no lote que descansou por 24 horas. Não foram observadas diferenças nos valores de pH entre o lote de animais que recebeu dieta de melaço e o que não recebeu estando ambos com o mesmo tempo de descanso.

    Influence of “ante-mortem” resting time and molasses diet upon pH levels of equines meat (Equus caballus were studied. It was measured the pH of triceps brachial and biceps femoral muscles in twenty four adults and hybrids equines with approximately  the same weights. The animals were divided, before death, in six groups with ";ante-mortem"; resting time of zero, six, fourteen, eighteen and twenty-four hours, respectively. The animals groups with eighteen hours of rest were divided in two sub-groups and one received water solution with 5% of molasses. The pH was measured using pH meter micronal with zero, six, twelve, eighteen, twenty-four and thirty hours after death. The group with smaller pH levels was the group with twenty-four hours of “ante-mortem” resting. Differences in pH levels were not observed between the group fed with water solution with 5% of molasses and the group not fed, but with the same time of rest.

  1. Evaluation of Themeda triandra as an indicator for monitoring the effects of grazing and fire in the Bontebok National Park

    Scientific Electronic Library Online (English)

    Peter, Novellie; Tineke, Kraaij.

    Full Text Available Up until 2004, the burning regime applied in the Bontebok National Park was aimed at maintaining grazing conditions suitable for bontebok (Damaliscus pygargus pygargus). It was, however, not suitable for maintaining plant species diversity, an increasingly urgent conservation priority for the park. [...] Accordingly, the burning regime was changed in 2004 to increase the interval between fires. A possible unintended outcome of the new burning regime is the spread of grazing lawns which is likely to be deleterious for maintaining the diversity of rare plants. Red grass, Themeda triandra, a species often locally abundant in areas preferred by bontebok, is potentially a good indicator of the anticipated change because, although it persists with moderate grazing, it is sensitive to localised intense grazing and will decrease on grazing lawns. To gauge the potential of this indicator, the canopy spread cover, degree of defoliation and inflorescence production of T. triandra was determined at 13 permanently marked sites in November 2005. The results are compared with a survey conducted 20 years previously (October-November 1984 and October-November 1985) using similar methodology. The results suggest that T. triandra remained abundant over the previous 20 years' application of the prior burning regime. In 1984-1985, defoliation of T. triandra was high within 1 year after a fire but declined quickly thereafter. In 2005, the tendency for the defoliation level to decline with increasing time after a fire was still apparent, but it was much less marked than in the previous survey period. A likely cause of this was the fact that Cape mountain zebra (Equus zebra zebra) and red hartebeest (Alcelaphus buselaphus caama) were present in 2005 but absent in 1984-1985 and these taller-grass grazers would have contributed to the use of the older veld. Provided it is interpreted together with other monitoring programmes, the use of T. triandra cover and defoliation intensity appears promising as an efficient indicator of some of the potentially deleterious outcomes of the interactions between herbivory and the new burning regime. CONSERVATION IMPLICATIONS: The conservation objectives of maintaining (1) large mammal herbivory as an ecological process and (2) plant species diversity may be difficult to reconcile with each other in the highly fragmented renosterveld and lowland fynbos ecosystems. This paper explores a rapid approach to monitoring impacts of bontebok and other grazing ungulates.

  2. The Role of Science in Managed Aquifer Recharge--the Equus Beds aquifer near Wichita, Kansas Andrew Ziegler, Director Brian Kelly, Office Chief Michael Jacobs, Manager of Water Planning and Production Debra Ary, Engineer, Water Systems Planning (Invited)

    Science.gov (United States)

    Ziegler, A. C.; Jacobs, M.; Ary, D.; Kelly, B.

    2013-12-01

    Data collection and interpretation using statistical, geochemical, and numerical simulation tools are essential parts of a long-term cooperative study between the city of Wichita, U.S. Geological Survey, and others to describe water quantity and quality conditions in a 165 square-mile part of the Equus Beds aquifer and Arkansas and Little Arkansas Rivers. The Equus Beds aquifer, eastern part of the High Plains Aquifer in south-central Kansas, is a vital water resource for agriculture and city of Wichita. Withdrawals for public supply began in the 1940s and agricultural irrigation began in the 1950-60s. These withdrawals led to water-level declines of up to 40 feet (historic low in 1993), a storage loss of 250,000 acre feet compared to predevelopment, and may enhance movement of chloride contamination from a past oilfield disposal area near Burrton and from natural chloride along the Arkansas River. Monitoring data and modeling show chloride near Burrton moved about 3 miles in 45 years, is about 1 mile away from the nearest public supply wells, and will continue to move for decades to centuries making the water unusable for irrigation or water supply without treatment. These concerns led to development of Wichita's 1993 integrated local water-supply plan that increased use of Cheney Reservoir and implemented aquifer storage and recovery (ASR) within the aquifer using high flows from the Little Arkansas River. ASR benefits include replacing depleted storage and slowing chloride movement. Decreased withdrawals, increased precipitation, and artificial recharge increased water levels and added 100,000 acre feet of storage through 2010, but drought since 2011 has increased withdrawals. A calibrated model will be used to simulate transport of chloride under several withdrawal scenarios using MODFLOW coupled with SEAWAT. Since 1995, water-quality data collection for more than 400 organic and inorganic compounds in surface water, treated source water for artificial recharge, and groundwater identified indicator bacteria, atrazine, chloride, sodium, nitrate, arsenic, iron, and manganese as constituents of concern exceeding water-quality criteria in baseline samples. Techniques were developed to estimate Little Arkansas River water quality in real-time for treatment. Geochemical modeling using PHREEQC and PHAST shows that groundwater quality is not changed if groundwater and recharge water are of similar redox potential. If different, calcite or metal hydroxides may precipitate and decrease water infiltration. A network of 38 locations with shallow and deep wells characterizes the recharge quantities and qualities for the city of Wichita to withdraw when needed from storage. Through 2013, the Demonstration project and Phase 1 and 2 facilities (capacity 40 MGD) have artificially recharged about 2 billion gallons. Total construction costs are about $300,000,000. Data-collection, interpretative geochemical and numerical simulations and water-quality transport modeling tools developed in the past 70 years are a scientific foundation to effectively and objectively manage this aquifer system.

  3. 9 CFR 88.1 - Definitions.

    Science.gov (United States)

    2010-01-01

    ...of these, propelled or drawn by mechanical power. Equine. Any member of the Equidae family, which includes horses, asses, mules, ponies, and zebras. Euthanasia. The humane destruction of an animal by the use of an...

  4. Nõela all : Igakuine vinüülitutvustus / Ninja

    Index Scriptorium Estoniae

    Ninja

    1999-01-01

    Heliplaatide The Ram Trilogy "Chapter Three EP", JMJ & Richie "Zebra 3/Temporal Mechanics", USG feat. Monica Elam "Life Is 4 Living", Shy FX "bambaata ", Bloefield "Nexus", Leon Thomas "The Antology" tutvustus

  5. Ask a Scientist

    Science.gov (United States)

    Howard Hughes Medical Institute

    Have a question about biology? This site hosted by the Howard Hughes Medical Institute, fields about 3,500 questions each year on such perplexing topics as the molecular bases for zebras' stripes and why flu season occurs during winter.

  6. 9 CFR 98.30 - Definitions.

    Science.gov (United States)

    2010-01-01

    ...CERTAIN ANIMAL EMBRYOS AND ANIMAL SEMEN Certain Animal Semen § 98.30 Definitions. ...goats, other ruminants, swine, horses, asses, zebras, and poultry...interchange or movement of animals. Horses. Horses, asses, mules,...

  7. 50 CFR 15.33 - Species included in the approved list.

    Science.gov (United States)

    2010-10-01

    ...Poephila acuticauda Long-tailed grassfinch. Poephila bichenovii Double-barred finch. Poephila cincta Parson finch. Poephila guttata Zebra finch. Poephila personata Masked finch. Serinus canaria Common Canary. 1...

  8. 75 FR 17758 - Approved Recovery Plan for the Scaleshell Mussel

    Science.gov (United States)

    2010-04-07

    ...unknown, particularly of the juvenile stage. Water quality degradation, sedimentation, channel destabilization, and habitat destruction...scaleshell throughout its range. The spread of the nonnative zebra mussel (Dreissena polymorpha) may threaten scaleshell...

  9. 9 CFR 130.1 - Definitions.

    Science.gov (United States)

    2010-01-01

    ...Center for Import-Export, 4700 River Road, Unit 38, Riverdale, Maryland...educational purposes. Equine. Any horse, ass, mule, or zebra. Export...permit or authorization. Miniature horse. Any horse which at maturity measures 34...

  10. The Secret Lives of Wild Animals

    Science.gov (United States)

    Scientists are collecting new information about the secret lives of wild animals using modern technologies like global tracking systems and ultra-miniaturized sensors. Learn about research into some rarely seen behaviors of deer, ocelots, agouti, zebras, dragonflies, and seals.

  11. A comparison of data management systems used in high energy physics

    International Nuclear Information System (INIS)

    Data-management systems for defining data and manipulating them with FORTRAN programs have become increasingly important. We compare three systems that were developed within the high-energy physics community: BOS, JAZELLE and ZEBRA. (orig.)

  12. Influence of social upbringing on the activity pattern of captive lion Panthera leo cubs: Benefits of behavior enrichment

    Directory of Open Access Journals (Sweden)

    Sibonokuhle NCUBE, Hilton Garikai Taambuka NDAGURWA

    2010-08-01

    Full Text Available The influence of social upbringing on the activity pattern of lion Panthera leo cubs was investigated at three sites. In this study, stimulus objects such as sticks, grass, fresh dung (elephant Loxondota africana, zebra Equus quagga, impala Aepyceros melampus, duiker Sylvicapra grimmia, kudu Tragelaphus strepsiceros, giraffe Giraffa camelopardalis and wildebeest Connochaetes taurinus and cardboard boxes, were utilized in an enrichment program aimed at encouraging active behaviors of captive lion cubs at Antelope Park and Masuwe. Lion cubs at Chipangali were not behaviorally enriched. Activity patterns were recorded for 10 days at each site. We recorded moving, resting, playing, grooming, visual exploration and display of hunting instincts. We found that behavioral enrichment enhanced the active behaviors of captive lion cubs. Orphan-raised cubs spent more time moving, playing and displaying hunting instincts than mother-raised cubs, but the time spent grooming was similar across areas and suggests that grooming is not influenced by enrichment. Mother-raised cubs spent more time engaged in visual exploration than orphan-raised cubs and this could be a behavior acquired from mothers or a result of confidence to explore because of their presence. Activity patterns were different among time treatments across our three study sites. Based on these findings, we suggest that lion cubs raised in captivity could benefit from behavioral enrichment to encourage active behaviors essential for eventual reintroduction into the wild [Current Zoology 56 (4: 389–394, 2010].

  13. Toevoegings tot die blomplantlys van die Bergkwagga Nasionale Park

    Directory of Open Access Journals (Sweden)

    B.L. Penzhorn

    1977-08-01

    Full Text Available

    Additions to the check list of flowering plants of the Mountain Zebra National Park. Thirteen additional flowering plant species are reported from the Mountain Zebra National Park, increasing the total reported to 371 species.

  14. DNA Barcoding and Microsatellites Help Species Delimitation and Hybrid Identification in Endangered Galaxiid Fishes

    OpenAIRE

    Vanhaecke, Delphine; Garcia De Leaniz, Carlos; Gajardo, Gonzalo; Young, Kyle; Sanzana, Jose; Orellana, Gabriel; Fowler, Daniel; Howes, Paul; Monzon-Arguello, Catalina; Consuegra, Sofia

    2012-01-01

    The conservation of data deficient species is often hampered by inaccurate species delimitation. The galaxiid fishes Aplochiton zebra and Aplochiton taeniatus are endemic to Patagonia (and for A. zebra the Falkland Islands), where they are threatened by invasive salmonids. Conservation of Aplochiton is complicated because species identification is hampered by the presence of resident as well as migratory ecotypes that may confound morphological discrimination. We used DNA barcoding (COI, cyto...

  15. Elevated aromatase activity in forebrain synaptic terminals during song

    OpenAIRE

    Remage-healey, Luke; Oyama, Randi K.; Schlinger, Barney A.

    2009-01-01

    The enzyme aromatase (which converts androgens into oestrogens) is expressed throughout the brain in zebra finches. Aromatase is enzymatically active in both cell bodies and synaptic terminals of neurones of the songbird brain, particularly within forebrain motor and auditory networks. Aromatisation within synaptic terminals could thus provide localised and acute modulatory oestrogens within the forebrain during singing and/or audition. In male zebra finches, we tested the hypothesis that for...

  16. Economic Cost of Pedestrian Injuries in Stockholm City

    Directory of Open Access Journals (Sweden)

    Sandra Pahrne

    2014-11-01

    Full Text Available Objective: To conduct a cost analysis of pedestrian injuries at zebra crossings (marked lines only in Stockholm city during 2008, and propose an intervention for reducing these incidents. Cost savings for the intervention are calculated and presented. Method: A Cost of Illness (COI method was used to calculate the cost for pedestrian injuries at zebra crossings. Cost of Illness included direct and indirect costs and excluded intangible costs due to lack of data. Data and statistics from STRADA, PAR and calculations from MSB were used to perform the COI. Results: During 2008, 73 pedestrians were injured at zebra crossings in Stockholm city, amounting an estimated social cost of 10.8 million Swedish Krona (SEK (severe injuries 9.2 million SEK, minor injuries 1.6 million SEK. The costs for reducing pedestrian injuries and related social burden via the proposed intervention (zebra crossings constructed alongside asphalt speed bumps with adjacent lights on both sides of the crossing were estimated to be 250,000 SEK at roads without intersections, and 1.6 million SEK at roads with an intersection. Conclusion: Pedestrian injuries place a large financial burden on society each year. It is recommended to add speed bumps and adjacent lights to zebra crossings where most pedestrian injuries occur. The intervention would reduce pedestrian injuries and also decrease the cost for the society due to these injuries. Cost savings for the intervention depend on the kind of injury avoided and what kind of road the intervention is built on.

  17. Congelamiento de semen de burro (Equus asinus) / Freezing of donkey semen (Equus asinus)

    Scientific Electronic Library Online (English)

    Igor Frederico, Canisso; Fernando Andrade, Souza; Jeanny Marlén, Ortigoza Escobar; Giovanni Ribeiro de, Carvalho; Mina C., Davies Morel; Erotides, Capistrano da Silva; José, Domingos Guimarães; Anali, Linhares Lima.

    2008-07-01

    Full Text Available Por muitas décadas, o desenvolvimento e utilização da inseminação artificial nos eqüídeos, principalmente com sêmen congelado, esteve restrito devido a imposições por muitas associações de criadores que não permitiam a utilização da técnica. Recentemente, as legislações das associações de criadores [...] de eqüídeos em diversos países do mundo se tornaram mais flexíveis, permitindo o registro de produtos oriundos de sêmen congelado. No Brasil, frente a essa nova mudança, a principal associação criadores de jumentos (Associação Brasileira de Criadores de Jumento Pêga), revisou seus conceitos e passou a permitir a utilização desta biotecnologia. Atualmente em muitos países, o maior interesse no reprodutor jumento é para a produção de muares, pois esses animais são produtos bastante desejáveis no meio rural, devido reunirem as melhores características destas duas espécies. O primeiro trabalho envolvendo o congelamento de sêmen de jumentos utilizaram diluidor a base de gema de ovo, glicerol e ampolas de vidro como sistema de envase baseados na metodologia de congelamento de touros. Contudo, apesar da longa data de início dos estudos, poucas pesquisas têm sido direcionadas à espécie, em especial a biotecnologias do sêmen. Nesta revisão de literatura discute se as principais técnicas de congelamento de sêmen de eqüídeos bem como descrição detalhada dos estudos envolvendo o congelamento de sêmen da espécie asinina. Abstract in spanish Por muchas décadas, el desarrollo y utilización de la inseminación artificial en los équidos, especialmente con semen congelado, estuvo restringido, principalmente, por imposiciones de las asociaciones de criadores. Recientemente, las legislaciones de criadores de équidos en varios países se han tor [...] nado más flexibles, permitiendo el registro de productos oriundos de semen congelado. En el Brasil, frente a ese nuevo cambio, la principal asociación de criadores de burros (Associação Brasileira de Criadores de Jumento Pêga) revisó sus conceptos y comenzó a permitir la utilización de esta biotecnología. Asimismo, en muchos países, el mayor interés en el asno o burro como semental está relacionado a la producción de mulares, pues estos animales son deseables en el medio rural, debido a que reúnen las mejores características del burro y del caballo. Los primeros trabajos en congelamiento de semen de asnos utilizaron dilutores a base de yema de huevo y glicerol, y ampolletas de vidrio como sistema de envase, basados en la metodología de congelamiento de toros. Sin embargo, pese al tiempo transcurrido, pocas investigaciones han sido dirigidas a esta especie, en especial a biotecnologías del semen. En esta revisión de literatura se discuten las principales técnicas de congelamiento de semen de équidos y se describen estudios referentes al congelamiento de semen de la especie asnal. Abstract in english For decades, the development and use of the artificial insemination in the equine, especially with frozen semen, was restricted due to impositions of equine breeders associations that opposed the use of the technique. Recently, these legislations have become more flexible in several countries, allow [...] ing the registration of products originating from frozen semen. In Brazil, based on these changes, the main donkey breed association (Brazilian Breeders Association of the Pêga Donkeys) revised their concepts and started to allow the use of this biotechnology. The current interest in many countries for the donkey sire is the production of mules, because their acceptability as these animals inherits suitable characteristics of both donkeys and horses. The first reports on donkey frozen semen used extenders based on egg yolk and glycerol, packed in glass ampoules, and followed the existing methodology for freezing bull semen. However, despite of the elapsed time, few research works have been carried out on this species, especially on semen. This literature review discussed the main techniques of freezi

  18. Hunting by male lions: ecological influences and socioecological implications.

    Science.gov (United States)

    Funston; Mills; Biggs; Richardson

    1998-12-01

    In the Kruger National Park, male lions, Panthera leo, acquire most of their food by hunting rather than scavenging. This study, the most intensive to date of male lion ecology, showed that in savanna woodlands, with high buffalo, Syncerus caffer, densities, male lions were frequent and successful hunters. The main prey species of all male group types, but particularly nonterritorial males, was buffalo. By contrast, females preyed more frequently on the most abundant medium-sized ungulates, such as wildebeest, Connochaetes taurinus, and zebra, Equus burchelli. Thus intraspecific prey selection separation was based primarily on intersexual and, to a lesser extent, social differences. Furthermore, both nonterritorial males and pride females located their favoured prey, buffalo and medium-sized ungulates, respectively, more often than other prey. We investigated the influence of several ecological variables on the socioecology of male lions, particularly as we had determined that territorial males spent little time with their pride females and tended to hunt by themselves in their respective male coalitions. Further analysis showed that in a range of ecosystems in southern and eastern Africa the proportion of time territorial males spent with, and thus scavenged from, their pride females was strongly influenced by vegetation structure, and therefore probably by the assemblage of available ungulates. In open systems, territorial males were, therefore, likely to be encountered with pride females, whereas in more wooded areas they were likely to be encountered away from their pride females. We suggest that this is because vegetation structure influences food/prey availability and hunting success and influences territory maintenance and/or cub defence. (c) 1998 The Association for the Study of Animal Behaviour. PMID:9933529

  19. FRECUENCIA DE Babesia spp. EN CABALLOS DE MONTERÍA, CÓRDOBA (COLOMBIA) / FREQUENCY OF Babesia spp. IN HORSES OF MONTERIA, CORDOBA (COLOMBIA)

    Scientific Electronic Library Online (English)

    Alfonso, Calderón; José, Cardona; Óscar, Vergara.

    2013-12-30

    Full Text Available La Babesiosis equina o piroplasmosis equina, enfermedad que se transmite a los caballos por las garrapatas, es la principal restricción internacional para la movilización de los equinos. Es producida por los protozoos Theileria equi y Babesia caballi. Además de los caballos, afecta a mulas, asnos y [...] cebras. Por medio de muestreo por conveniencia, se implementó un estudio transversal, donde se seleccionaron seis pesebreras en Montería (Córdoba), en las que se recolectaron 126 muestras de sangre de equinos (Equus ferus caballus), en que se determinó el hematocrito y se colorearon, mediante tinción de Wright, para determinar la frecuencia de Babesiosis. El 18,25% de las muestras fueron positivas a Babesia spp. Se analizaron diferentes variables, como sistema de alimentación, edad, sexo, color y raza, para ser relacionadas con la frecuencia de Babesia spp. en equinos. La media general del hematocrito (Hto) fue 34,2% ± 6,2, con un intervalo de confianza (95%) de 33,1 a 35,2%. Para los equinos negativos, el promedio del Hto fue del 34,5% ± 5,2 y, de los positivos, del 32,9 ± 9,4%; no se encontraron diferencias significativas entre estos promedios. Se determinó que en los diferentes sistemas de manejo de los equinos en la ciudad de Montería, se presentaron casos de babesiosis equina y se hace necesario implementar un programa integral de control de vectores. Abstract in english Equine babesiosis or equine piroplasmosis, disease transmitted to horses by ticks, is the main restriction of international horse mobilization. It is produced by the protozoa Babesia caballi or Theileria equi, which besides horses, affect mules, donkeys and zebras. Through a convenience sample, a cr [...] oss sectional study was implemented and six stables in Monteria (Cordoba) were selected, taking 126 blood samples of horses (Equus ferus caballus), in which by hematocrit and staining by Wright's stain the frequency of babesiosis was determined. A 18.25% of the samples were positive for Babesia spp. Different variables such as feeding system, age, sex, color and race were analyzed and related to the frequency of positive Babesia spp. in horses. The general average of hematocrit was 34.2 ± 6.2% with a confidence interval (95%) of 33.1 at 35.2%. For seronegatives horses the average of the hematocrit was 34.5 ± 5.2% and for seropositive horses 32.9 ± 9.4%; no significant difference was found between these averages. In was determined that in the different horse management systems in Monteria cases of equine babesiosis are present and the need of a comprehensive vector control program has to be implemented.

  20. Cytogenetic divergence between two sympatric species of Characidium (Teleostei, Characiformes, Crenuchidae) from the Machado River, Minas Gerais, Brazil

    Scientific Electronic Library Online (English)

    Alexandre Rodrigues da, Silva; Edson Luis, Maistro.

    Full Text Available Cytogenetic studies were performed on two sympatric species of Characidium, C. gomesi and C. cf. zebra, from the Grande River basin, Minas Gerais State, Brazil. Although both species had a chromosome number of 50 with a karyotype exclusively consisting of meta- and submetacentric chromosomes, inters [...] pecific diversity was detected concerning the size of the two first chromosome pairs of the karyotypes. Active nucleolus organizer regions (NORs) were located at the terminal position on the long arm of the 17th pair of C. gomesi and at subterminal position on the long arm of the 23rd pair of C. cf. zebra. For both species the fluorochrome CMA3 stained only the NOR-bearing pair of chromosomes. The heterochromatin pattern also showed some differentiation between these species restricted to the centromeric or pericentromeric region of C. cf. zebra and practically absent in C. gomesi. These data are discussed concerning chromosome diversification in this fish group.

  1. The Culture of Sound: A Case Study of Birdsong Competition in Chana District, Thailand

    Directory of Open Access Journals (Sweden)

    Aphichet Kirichot

    2014-09-01

    Full Text Available Southeast Asian birdsong competitions are vital to the makeup of the Southern Thai economy. This is a qualitative research that uses observation, interview and document study to examine the zebra dove culture of Chana District in Songkhla Province. The research results show that vocal zebra dove competitions stimulate and drive the economy and society of Chana District. Zebra dove breeding is a large and lucrative occupation in the area that has spawned a number of supplementary professions, including birdcage production. The success of local breeding has given Chana an international reputation and has been used as a stimulus for political demonstrations. The original spirit of the songbird culture remains as part of a highly developed financial system.

  2. Epstein-Barr virus BZLF1 trans activator induces the promoter of a cellular cognate gene, c-fos.

    OpenAIRE

    Flemington, E.; Speck, S. H.

    1990-01-01

    The Epstein-Barr virus BZLF1 gene product ZEBRA is a DNA-binding protein that is partially homologous to c-Fos, binds specifically to AP-1 sites, and can induce the lytic cycle in latently infected B lymphocytes. Induction of the viral lytic cycle can also be achieved by treatment with the phorbol ester 12-O-tetrade-canoylphorbol-13-acetate, a reagent which activates gene expression in part through AP-1 (Jun/Fos). In this article the interrelationship between ZEBRA and AP-1 is extended by the...

  3. Metaphyseal bands in osteogenesis imperfecta

    Directory of Open Access Journals (Sweden)

    Suresh S

    2010-01-01

    Full Text Available An increasing number of patients with osteogenesis imperfecta are undergoing pamidronate therapy to prevent the incidence of fragility fractures. The authors herein report a child aged 3 years who received five cycles of pamidronate, resulting in metaphyseal bands, known as "zebra lines."

  4. Metaphyseal bands in osteogenesis imperfecta

    OpenAIRE

    Suresh S; Thomas John

    2010-01-01

    An increasing number of patients with osteogenesis imperfecta are undergoing pamidronate therapy to prevent the incidence of fragility fractures. The authors herein report a child aged 3 years who received five cycles of pamidronate, resulting in metaphyseal bands, known as "zebra lines."

  5. Development and application of a NaNiCl{sub 2}-battery for industrial trucks regarding the requirements cycle life, safety and reliability. Final report; Entwicklung und Erprobung einer NaNiCl{sub 2}-Batterie fuer Flurfoerderzeuge unter besonderer Beruecksichtigung der Aspekte Lebensdauer, Sicherheit und Zuverlaessigkeit. Schlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Boehm, H.; Beyermann, G.; Bulling, M.

    1996-07-01

    Two NaNiCl{sub 2}-battery types including the battery controller and peripheral equipment have been developed for the application in fork lift trucks and driverless transportation. The batteries have been tested and evaluated on bench testing as well as in fork lift trucks and driverless trucks in practical application. The field tests have been performed by the subcontractors Still, Mercedes-Benz and Indumat. All test results have shown that the NaNiCl{sub 2}-battery (ZEBRA-battery) is well suited for the application in industrial traction. A series development together with a cost reduction programme have to be performed ahead of the introduction of the ZEBRA-battery into the market for industrial traction batteries. (orig.) [Deutsch] Im Rahmen des Vorhabens wurden zwei NaNiCl{sub 2}-Batterietypen, eine fuer die Anwendung in Gabelstaplern, die andere fuer den Einsatz in fahrerlosen Transportsystemen (FTS), einschliesslich des Batteriesteuergeraetes und der Batterieperipherie entwickelt. Die Batterien wurden auf Teststaenden im Labor sowie in Gabelstaplern und FTS unter Praxisbedingungen erprobt. Der praktische Einsatz erfolgte bei den Unterauftragnehmern Still, Mercedes-Benz und Indumat. Die Ergebnisse haben gezeigt, dass die NaNiCl{sub 2}-Batterie (ZEBRA-Batterie) fuer die Anwendung in Gabelstaplern und FTS geeignet ist. Insbesondere wurde nachgewiesen, dass die NaNiCl{sub 2}-Batterie im Gegensatz zu anderen Batteriesystemen einen Zweischichtbetrieb von Gabelstaplern ohne Batteriewechsel ermoeglicht. Vor Einfuehrung der ZEBRA-Batterie in den Flurfoerdermarkt muss die Serienentwicklung bei gleichzeitiger Senkung der Herstellkosten durchgefuehrt werden. (orig.)

  6. Sperm length variation as a predictor of extrapair paternity in passerine birds.

    Czech Academy of Sciences Publication Activity Database

    Lifjeld, J. T.; Laskemoen, T.; Kleven, O.; Albrecht, Tomáš; Robertson, R. J.

    2010-01-01

    Ro?. 5, ?. 10 (2010), e13456. ISSN 1932-6203 R&D Projects: GA MŠk LC06073 Institutional research plan: CEZ:AV0Z60930519 Keywords : postcopulatory sexual selection * pair paternity * intraspecific variation * molecular phylogeny * mating systems * zebra finch Subject RIV: EG - Zoology Impact factor: 4.411, year: 2010

  7. Evidence of the adaptive evolution of immune genes in chicken

    Directory of Open Access Journals (Sweden)

    Cormican Paul

    2009-12-01

    Full Text Available Abstract The basis for understanding the characteristics of gene functional categories in chicken has been enhanced by the ongoing sequencing of the zebra finch genome, the second bird species to be extensively sequenced. This sequence provides an avian context for examining how variation in chicken has evolved since its divergence from its common ancestor with zebra finch as well as well as a calibrating point for studying intraspecific diversity within chicken. Immune genes have been subject to many selective processes during their evolutionary history: this gene class was investigated here in a set of orthologous chicken and zebra finch genes with functions assigned from the human ortholog. Tests demonstrated that nonsynonymous sites at immune genes were highly conserved both in chicken and on the avian lineage. McDonald-Kreitman tests provided evidence of adaptive evolution and a higher rate of selection on fixation of nonsynonymous substitutions at immune genes compared to that at non-immune genes. Further analyses showed that GC content was much higher in chicken than in zebra finch genes, and was significantly elevated in both species' immune genes. Pathogen challenges are likely to have driven the selective forces that have shaped variation at chicken immune genes, and continue to restrict diversity in this functional class.

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

    Directory of Open Access Journals (Sweden)

    JamesL.Goodson

    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.

  9. Research and development at Winfrith - 25 years on

    International Nuclear Information System (INIS)

    A short account is given of the work of the UKAEA Winfrith Establishment. The following are included: reactors (ZEBRA, DRAGON and SGHWR); radioactive waste management; criticality and radiation shielding (DIMPLE and NESTOR reactors); reactor safety (including PWR studies); instrumentation and control; commercial programmes; site services. (U.K.)

  10. Type II and IV radio bursts in the active period October-November 2003

    CERN Document Server

    Petoussis, V; Kontogeorgos, A; Moussas, X; Preka-Papadema, P; Hillaris, A; Caroubalos, C; Alissandrakis, C E; Bougeret, J -L; Dumas, G; 10.1063/1.2347978

    2010-01-01

    In this report we present the Type II and IV radio bursts observed and analyzed by the radio spectrograph ARTEMIS IV1, in the 650-20MHz frequency range, during the active period October-November 2003. These bursts exhibit very rich fine structures such fibers, pulsations and zebra patterns which is associated with certain characteristics of the associated solar flares and CMEs.

  11. Identification and definitions of Electrical Penetration Graph (EPG) waveforms for the potato psyllid, Bactericera cockerelli, on susceptible potato.

    Science.gov (United States)

    The potato psyllid, Bactericera cockerelli, is the vector of Ca. Liberibacter psyllaurous/solanacearum, a bacterium associated with a lethal potato disease with tuber-striping symptoms, termed Zebra Chip (ZC). Presently, there are no effective management tactics for ZC, although research to aid de...

  12. Communicating Science Concepts through Art: 21st-Century Skills in Practice

    Science.gov (United States)

    Buczynski, Sandy; Ireland, Kathleen; Reed, Sherri; Lacanienta, Evelyn

    2012-01-01

    There is a dynamic synergy between the visual arts and the natural sciences. For example, science relies heavily on individuals with visual-art skills to render detailed illustrations, depicting everything from atoms to zebras. Likewise, artists apply analytic, linear, and logical thinking to compose and scale their work of art. These parallel…

  13. 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

    Ro?. 119, ?. 10 (2013), s. 907-917. ISSN 0179-1613 R&D Projects: GA ?R(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

  14. Human Impact

    Science.gov (United States)

    Collection of nine classroom activities that focus on human impact on the environment. Topics include: oil spills; oil consumption; oil tanker size; greenhouse effect; salt water incursion; ozone hole and its affect on the food web; and zebra mussels. Each activity provides list of materials needed, background information, and procedure.

  15. Rapid molecular detection of invasive species in ballast and harbor water by integrating environmental DNA and light transmission spectroscopy.

    Science.gov (United States)

    Egan, Scott P; Grey, Erin; Olds, Brett; Feder, Jeffery L; Ruggiero, Steven T; Tanner, Carol E; Lodge, David M

    2015-04-01

    Invasive species introduced via the ballast water of commercial ships cause enormous environmental and economic damage worldwide. Accurate monitoring for these often microscopic and morphologically indistinguishable species is challenging but critical for mitigating damages. We apply eDNA sampling, which involves the filtering and subsequent DNA extraction of microscopic bits of tissue suspended in water, to ballast and harbor water sampled during a commercial ship's 1400 km voyage through the North American Great Lakes. Using a lab-based gel electrophoresis assay and a rapid, field-ready light transmission spectroscopy (LTS) assay, we test for the presence of two invasive species: quagga (Dreissena bugensis) and zebra (D. polymorpha) mussels. Furthermore, we spiked a set of uninfested ballast and harbor samples with zebra mussel tissue to further test each assay's detection capabilities. In unmanipulated samples, zebra mussel was not detected, while quagga mussel was detected in all samples at a rate of 85% for the gel assay and 100% for the LTS assay. In the spiked experimental samples, both assays detected zebra mussel in 94% of spiked samples and 0% of negative controls. Overall, these results demonstrate that eDNA sampling is effective for monitoring ballast-mediated invasions and that LTS has the potential for rapid, field-based detection. PMID:25686279

  16. Dicty_cDB: SFK231 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available SF (Link to library) SFK231 (Link to dictyBase) - - - Contig-U14968-1 SFK231F (Link to Original ... 7759 )alcohol dehydrogenase (EC 1.1.1.1) 3 - zebra fish ... 268 1e-70 AF399909_1( AF399909 |pid:none) Danio re ...

  17. Dicty_cDB: SHB103 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available SH (Link to library) SHB103 (Link to dictyBase) - - - Contig-U13024-1 - (Link to Original site) ... 33 7.4 JC7572( JC7572 )somite Maf1 protein - zebra fish ... 33 7.4 protein update 2009. 1.15 PSORT psg: 0.78 g ...

  18. Dicty_cDB: SFK179 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available SF (Link to library) SFK179 (Link to dictyBase) - - - Contig-U14968-1 SFK179F (Link to Original ... 7759 )alcohol dehydrogenase (EC 1.1.1.1) 3 - zebra fish ... 293 4e-78 AF399909_1( AF399909 |pid:none) Danio re ...

  19. Performance Evaluation and Software Design for EVA Robotic Assistant Stereo Vision Heads

    Science.gov (United States)

    DiPaolo, Daniel

    2003-01-01

    The purpose of this project was to aid the EVA Robotic Assistant project by evaluating and designing the necessary interfaces for two stereo vision heads - the TracLabs Biclops pan-tilt-verge head, and the Helpmate Zebra pan-tilt-verge head. The first half of the project consisted of designing the necessary software interface so that the other modules of the EVA Robotic Assistant had proper access to all of the functionalities offered by each of the stereovision heads. This half took most of the project time, due to a lack of ready-made CORBA drivers for either of the heads. Once this was overcome, the evaluation stage of the project began. The second half of the project was to take these interfaces and to evaluate each of the stereo vision heads in terms of usefulness to the project. In the key project areas such as stability and reliability, the Zebra pan-tilt-verge head came out on top. However, the Biclops did have many more advantages over the Zebra, such as: lower power consumption, faster communications, and a simpler, cleaner API. Overall, the Biclops pan-tilt-verge head outperformed the Zebra pan-tilt-verge head.

  20. Dynamics of Flare Processes and Variety of the Fine Structure of Solar Radio Emission over a Wide Frequency Range of 30 - 7000 MHz

    Science.gov (United States)

    Chernov, Gennady; Fomichev, Valery; Tan, Baolin; Yan, Yihua; Tan, Chengming; Fu, Qijun

    2015-01-01

    Radiobursts exhibiting fine structure observed over two years during the rising phase of Cycle 24 by the Chinese Solar Broadband Radio Spectrometer (SBRS/Huairou) in the range 1 - 7.6 GHz and the spectrograph IZMIRAN in the meter range (25 - 270 MHz) are analyzed. In five events the zebra structure, various fiber bursts, and fast pulsations were observed. These observations have great importance for testing different theoretical models of fine structure formation, as, for example, only for explaining the zebra structure more than ten mechanisms have been proposed. The events on 15 and 24 February 2011 are of the greatest interest. In the course of the flare on 15 February (which occurred close to the center of disk) the zebra structure was observed during three sequential flare brightenings. The polarization changed sign in the third. This behavior of polarization combined with images of the corresponding flare brightenings, obtained in extreme ultraviolet radiation by the Solar Dynamics Observatory (SDO/AIA, 171 Å), provides important clues. The polarization of radio emission in all three cases is related to the ordinary wave mode of radio emission. The zebra structure was present at frequencies 190 - 220 MHz in the Culgoora spectrum. The event on 24 February 2011 is remarkable, as the zebra structure at frequencies of 2.6 - 3.8 GHz was not polarized and it appeared during the magnetic reconnection observed by SDO/AIA 171 Å in this limb flare. In the event on 9 August 2011, for the first time, a superfine millisecond structure was registered simultaneously in the fast pulsations and the stripes of the zebra structure. In the event on 1 August 2010 after the zebra structure two families of fibers bursts with opposite frequency drifts were observed. On 19 April 2012 the fibers against the background of type III bursts were observed by IZMIRAN and Nançay spectrographs. In the band of 42 - 52 MHz a group of nine slowly drifting narrow-band (

  1. Quality assurance of proton beams using a multilayer ionization chamber system

    International Nuclear Information System (INIS)

    Purpose: The measurement of percentage depth-dose (PDD) distributions for the quality assurance of clinical proton beams is most commonly performed with a computerized water tank dosimetry system with ionization chamber, commonly referred to as water tank. Although the accuracy and reproducibility of this method is well established, it can be time-consuming if a large number of measurements are required. In this work the authors evaluate the linearity, reproducibility, sensitivity to field size, accuracy, and time-savings of another system: the Zebra, a multilayer ionization chamber system.Methods: The Zebra, consisting of 180 parallel-plate ionization chambers with 2 mm resolution, was used to measure depth-dose distributions. The measurements were performed for scattered and scanned proton pencil beams of multiple energies delivered by the Hitachi PROBEAT synchrotron-based delivery system. For scattered beams, the Zebra-measured depth-dose distributions were compared with those measured with the water tank. The principal descriptors extracted for comparisons were: range, the depth of the distal 90% dose; spread-out Bragg peak (SOBP) length, the region between the proximal 95% and distal 90% dose; and distal-dose fall off (DDF), the region between the distal 80% and 20% dose. For scanned beams, the Zebra-measured ranges were compared with those acquired using a Bragg peak chamber during commissioning.Results: The Zebra demonstrated better than 1% reproducibility and monitor unit linearity. The response of the Zebra was found to be sensitive to radiation field sizes greater than 12.5 × 12.5 cm; hence, the measurements used to determine accuracy were performed using a field size of 10 × 10 cm. For the scattered proton beams, PDD distributions showed 1.5% agreement within the SOBP, and 3.8% outside. Range values agreed within ?0.1 ± 0.4 mm, with a maximum deviation of 1.2 mm. SOBP length values agreed within 0 ± 2 mm, with a maximum deviation of 6 mm. DDF values agreed within 0.3 ± 0.1 mm, with a maximum deviation of 0.6 mm. For the scanned proton pencil beams, Zebra and Bragg peak chamber range values demonstrated agreement of 0.0 ± 0.3 mm with a maximum deviation of 1.3 mm. The setup and measurement time for all Zebra measurements was 3 and 20 times less, respectively, compared to the water tank measurements.Conclusions: Our investigation shows that the Zebra can be useful not only for fast but also for accurate measurements of the depth-dose distributions of both scattered and scanned proton beams. The analysis of a large set of measurements shows that the commonly assessed beam quality parameters obtained with the Zebra are within the acceptable variations specified by the manufacturer for our delivery system

  2. Quality assurance of proton beams using a multilayer ionization chamber system

    Energy Technology Data Exchange (ETDEWEB)

    Dhanesar, Sandeep; Sahoo, Narayan; Kerr, Matthew; Taylor, M. Brad; Summers, Paige; Zhu, X. Ronald; Poenisch, Falk; Gillin, Michael [Department of Radiation Physics and Proton Therapy Center, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Unit 94, Houston, Texas 77030 (United States); Department of Radiation Physics and Proton Therapy Center, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Unit 94, Houston, Texas 77030 and The University of Texas at Houston Graduate School of Biomedical Sciences, 6767 Bertner Avenue, S3.8344, Houston, Texas 77030 (United States); Department of Radiation Physics and Proton Therapy Center, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Unit 94, Houston, Texas 77030 (United States); Department of Radiation Physics and Proton Therapy Center, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard, Unit 94, Houston, Texas 77030 and The University of Texas at Houston Graduate School of Biomedical Sciences, 6767 Bertner Avenue, S3.8344, Houston, Texas 77030 (United States)

    2013-09-15

    Purpose: The measurement of percentage depth-dose (PDD) distributions for the quality assurance of clinical proton beams is most commonly performed with a computerized water tank dosimetry system with ionization chamber, commonly referred to as water tank. Although the accuracy and reproducibility of this method is well established, it can be time-consuming if a large number of measurements are required. In this work the authors evaluate the linearity, reproducibility, sensitivity to field size, accuracy, and time-savings of another system: the Zebra, a multilayer ionization chamber system.Methods: The Zebra, consisting of 180 parallel-plate ionization chambers with 2 mm resolution, was used to measure depth-dose distributions. The measurements were performed for scattered and scanned proton pencil beams of multiple energies delivered by the Hitachi PROBEAT synchrotron-based delivery system. For scattered beams, the Zebra-measured depth-dose distributions were compared with those measured with the water tank. The principal descriptors extracted for comparisons were: range, the depth of the distal 90% dose; spread-out Bragg peak (SOBP) length, the region between the proximal 95% and distal 90% dose; and distal-dose fall off (DDF), the region between the distal 80% and 20% dose. For scanned beams, the Zebra-measured ranges were compared with those acquired using a Bragg peak chamber during commissioning.Results: The Zebra demonstrated better than 1% reproducibility and monitor unit linearity. The response of the Zebra was found to be sensitive to radiation field sizes greater than 12.5 × 12.5 cm; hence, the measurements used to determine accuracy were performed using a field size of 10 × 10 cm. For the scattered proton beams, PDD distributions showed 1.5% agreement within the SOBP, and 3.8% outside. Range values agreed within ?0.1 ± 0.4 mm, with a maximum deviation of 1.2 mm. SOBP length values agreed within 0 ± 2 mm, with a maximum deviation of 6 mm. DDF values agreed within 0.3 ± 0.1 mm, with a maximum deviation of 0.6 mm. For the scanned proton pencil beams, Zebra and Bragg peak chamber range values demonstrated agreement of 0.0 ± 0.3 mm with a maximum deviation of 1.3 mm. The setup and measurement time for all Zebra measurements was 3 and 20 times less, respectively, compared to the water tank measurements.Conclusions: Our investigation shows that the Zebra can be useful not only for fast but also for accurate measurements of the depth-dose distributions of both scattered and scanned proton beams. The analysis of a large set of measurements shows that the commonly assessed beam quality parameters obtained with the Zebra are within the acceptable variations specified by the manufacturer for our delivery system.

  3. A genetic demographic analysis of Lake Malawi rock-dwelling cichlids using spatio-temporal sampling.

    Science.gov (United States)

    Husemann, Martin; Nguyen, Rachel; Ding, Baoqing; Danley, Patrick D

    2015-06-01

    We estimated the effective population sizes (Ne ) and tested for short-term temporal demographic stability of populations of two Lake Malawi cichlids: Maylandia benetos, a micro-endemic, and Maylandia zebra, a widespread species found across the lake. We sampled a total of 351 individuals, genotyped them at 13 microsatellite loci and sequenced their mitochondrial D-loop to estimate genetic diversity, population structure, demographic history and effective population sizes. At the microsatellite loci, genetic diversity was high in all populations. Yet, genetic diversity was relatively low for the sequence data. Microsatellites yielded mean Ne estimates of 481 individuals (±99 SD) for M. benetos and between 597 (±106.3 SD) and 1524 (±483.9 SD) individuals for local populations of M. zebra. The microsatellite data indicated no deviations from mutation-drift equilibrium. Maylandia zebra was further found to be in migration-drift equilibrium. Temporal fluctuations in allele frequencies were limited across the sampling period for both species. Bayesian Skyline analyses suggested a recent expansion of M. zebra populations in line with lake-level fluctuations, whereas the demographic history of M. benetos could only be estimated for the very recent past. Divergence time estimates placed the origin of M. benetos within the last 100 ka after the refilling of the lake and suggested that it split off the sympatric M. zebra population. Overall, our data indicate that micro-endemics and populations in less favourable habitats have smaller Ne , indicating that drift may play an important role driving their divergence. Yet, despite small population sizes, high genetic variation can be maintained. PMID:25891855

  4. Changes in lipid content and fatty acid composition along the reproductive cycle of the freshwater mussel Dreissena polymorpha: Its modulation by clofibrate exposure

    International Nuclear Information System (INIS)

    Total lipids and fatty acid profiles were determined along the reproductive cycle of the zebra mussel (Dreissena polymorpha). A total of 33 fatty acids with carbon atoms from 14 to 22 were identified: palmitic acid (16:0) was the most abundant fatty acid (13–24%) followed by docosahexaenoic acid (DHA; 22:6n?3), eicosapentaenoic acid (EPA; 20:5n?3) and palmitoleic acid (16:1n?7). Some individual fatty acids (16:0, 16:2n?4, 18:1n?7, 18:2n?6, 18:3n?4, 18:4n?3, 20:4n?3, 20:5n?3) were strongly related to reproductive events, while others having structural-type functions (18:0 and 22:6n?3) were rather stable during the study period. Multivariate analysis of the whole data set using the multivariate curve resolution alternating least squares method confirmed the strong relationship of fatty acid profiles with the reproductive cycle of zebra mussel. Additionally, the effects of the pharmaceutical clofibrate on lipid composition and fatty acid profiles were assessed following 7-day exposure of zebra mussels to a wide range of concentrations (20 ng/L to 2 mg/L). A significant reduction in total triglycerides (38%–48%) together with an increase in the amount of fatty acids per gram wet weight (1.5- to 2.2-fold) was observed in the exposed mussels. This work highlights the ability of clofibrate to induce changes on the lipidome of zebra mussels at concentrations as low as 200 ng/L. -- Highlights: ? Clofibrate exposure leads to a reduction of total triglycerides in zebra mussel. ? The amount of fatty acids per gram wet weight increased in exposed mussels. ? The effects were evidenced at concentrations of clofibrate as low as 200 ng/L. ? Fatty acid profiles were closely related to reproductive events.

  5. Socially dependent auditory laterality in domestic horses (Equus caballus).

    Science.gov (United States)

    Basile, Muriel; Boivin, Sarah; Boutin, Anaïs; Blois-Heulin, Catherine; Hausberger, Martine; Lemasson, Alban

    2009-07-01

    Laterality is now known to be an ubiquitous phenomenon among the vertebrates. Particularly, laterality of auditory processing has been demonstrated in a variety of species, especially songbirds and primates. Such a hemispheric specialization has been shown to depend on factors such as sound structure, species specificity and types of stimuli. Much less is known on the possible influence of social familiarity although a few studies suggest such an influence. Here we tested the influence of the degree of familiarity on the laterality of the auditory response in the domestic horse. This species is known for its social system and shows visible reactions to sounds, with one or two ears moving towards a sound source. By comparing such responses to the playback of different conspecific whinnies (group member, neighbor and stranger), we could demonstrate a clear left hemisphere (LH) preference for familiar neighbor calls while no preference was found for group member and stranger calls. Yet, we found an opposite pattern of ear side preference for neighbor versus stranger calls. These results are, to our knowledge, the first to demonstrate auditory laterality in an ungulate species. They open further lines of thought on the influence of the social "value" of calls and the listener's arousal on auditory processing and laterality. PMID:19283416

  6. Arthroscopy of septic carpitis in donkeys (Equus asinus

    Directory of Open Access Journals (Sweden)

    A.H. Elkasapy

    2014-11-01

    Full Text Available Experimental septic arthritis was induced in the radiocarpal joint of 18 donkeys by intra-articular injection of Staphylococcus aureus (3-4X106 CFU. The inoculated animals were divided into three groups (6 donkeys in each group. The arthroscopic examination was carried out before induction of septic carpitis and 3 days (group I, 14 days (group II, and 28 days (group III after induction of infection. The arthroscopic examination of group I revealed hyperemia of synovial membrane and hypertrophied villi. In group II, severe hyperemia of synovial membrane, hypertrophied villi, pannus in the joint cavity and beginning of articular cartilage erosion were found. In group III, severe hyperemia of synovial membrane, hypertrophied villi and more prominent articular cartilage erosion were present.

  7. BIOMETRIA PODAL DE EQUÍDEOS (Equus sp LINNAEUS, 1758 DE TRAÇÃO

    Directory of Open Access Journals (Sweden)

    Marcelo Domingues de Faria

    2014-06-01

    Full Text Available Horses have been widely used as a means of traction since ancient times, without regard to the damage hoofs are subjected, mainly through attrition, and by the impact forces acting at the time of traction. For the measurement of the hoofs we used a millimetric caliper, and to determine the angle of the parietal face with the ground, a 180o protractor. The following parameters were measured: length, width, height of the dorsal surface of the parietal face, width of the horn torus, height of the medial and lateral horn torus, the length and width of the corneal nail caps. We used 181 animals, employed in traction activity in the city of Petrolina (PE, Brazil. There were 56 horses, 97 donkeys and 28 mules, among males and females with different body weights and different ages. The results were tabulated and they can be used to determine the anatomical pattern of these animals in that region. It was possible to verify the practices to which the animals are subjected, like trimming, shoeing and excess load, which can result in poor load distribution on the limbs and nail capsule, generating locomotor disorders. We observed the medial-lateral imbalance of nail capsule, since the medial corneal torus was greater than the lateral one, triggering changes in poise and damaging dynamic and orthostatic positions, which could be solved by trimming and shoeing practices, reducing diseases of the locomotor apparatus.

  8. A Morphometric Study on the Skull of Donkey (Equus asinus) / Estudio Morfométrico del Cráneo del Burro (Equus asinus)

    Scientific Electronic Library Online (English)

    Lei, Zhu; XiaoDong, Shi; JunJie, Wang; JianGang, Chen.

    1306-13-01

    Full Text Available Se realizó un estudio sobre una serie de 16 cráneos pertenecientes a burros domésticos adultos, de sexo masculino. Se hicieron mediciones craneométricas en 40 partes diferentes de las muestras. Todas las características investigadas se expresaron como media ± desviación estándar, calculándose índice [...] s y proporciones cefálicas. Se compararon las mediciones craneométricas e índices cefálicos con los de caballos y ponis de la zona. La longitud del cráneo obtenida fue de 443,07±53,57 mm, con una anchura máxima del hueso cigomático de 169,09±17,64 mm. El tamaño del cráneo del burro se ubicó entre el de los caballos y los ponis locales. Se obtuvo un índice de cráneo de 38,23±0,85, un índice craneal de 45,01±2,83 y un índice facial de 67,80±3,79. Los índices craneal y de cráneo encontrados fueron cercanos a los valores correspondientes a los caballos y ponis locales. Los resultados de este estudio revelaron que el burro tenía una nariz más larga que el caballo y el poni. Además, la diferencia en longitud del cráneo en las tres especies representa la diferencia de longitud facial. Abstract in english The present study was carried out on a number of 16 skulls of adult male domestic donkeys. Craniometric measurements for 40 different parts of the skulls were made. All investigated features were expressed as Mean±SD. Cephalic indices and ratios were calculated by using the investigated features. Th [...] e craniometric measurements and cephalic indices had been compared with those of local horses and ponies. A skull length of 443.07±53.57 mm and a maximum zygomatic width of 169.09±17.64 mm were obtained. The size of donkey skull was between those of local horses and ponies. A skull index of 38.23±0.85, a cranial index of 45.01±2.83 and a facial index of 67.80±3.79 were obtained. Cranial index and skull index were found to be close in value to that of local horses and ponies. The results of this study revealed that donkey had a longer nose than local horse and pony, and the difference of skull length in the three species accounted for the facial length difference.

  9. Biometria podal de equídeos (Equus sp Linnaeus, 1758) de tração / Podal biometric of traction equidae (Equus sp Linnaeus, 1758)

    Scientific Electronic Library Online (English)

    Marcelo Domingues de, Faria; Maria Alice Maranhão, Santos; Laura Flávia Teixeira, Martins; Adriana, Gradela; Joaquim, Pereira Neto; Claudio Gomes Costa, Bandeira.

    2014-06-01

    Full Text Available Os equídeos têm sido largamente utilizados como meio de tração desde épocas remotas, sem que se atente às intempéries às quais as cápsulas ungueais são submetidas, principalmente pelo atrito, pelo impacto e pelas forças atuantes no momento da tração. Para a mensuração das cápsulas ungueais foi utili [...] zado paquímetro de aproximação milimetral e, para determinar a angulação da face parietal com o solo, transferidor de 180º. Os parâmetros das cápsulas ungueais mensurados foram: o comprimento, a largura, a altura da superfície dorsal da face parietal, a largura dos tórus córneos, a altura dos tórus córneos mediais e laterais, o comprimento e a largura da cunha córnea. Para confecção do presente trabalho foram utilizados 181 animais empregados em atividade de tração no Município de Petrolina (PE), sendo 56 equinos, 97 asininos e 28 muares, dentre machos e fêmeas, com diferentes massas corporais e diferentes idades. Os resultados foram tabulados e poderão servir de subsídio para determinação do padrão anatômico destes animais na referida região. Foi possível verificar as práticas às quais os animais são submetidos, como casqueamento, ferrageamento e excesso de carga, o que pode acarretar má distribuição da carga nos membros e na própria cápsula ungueal, gerando patologias do aparelho locomotor. Frequentemente, observava-se o desequilíbrio médio-lateral das úngulas, uma vez que o tórus córneo medial era maior que o lateral, desencadeando alterações no aprumo e prejudicando as posições ortostática e ortodinâmica, as quais poderiam ser resolvidos com práticas de casqueamento e ferrageamento, reduzindo as afecções do aparelho locomotor. Abstract in english Horses have been widely used as a means of traction since ancient times, without regard to the damage hoofs are subjected, mainly through attrition, and by the impact forces acting at the time of traction. For the measurement of the hoofs we used a millimetric caliper, and to determine the angle of [...] the parietal face with the ground, a 180º protractor. The following parameters were measured: length, width, height of the dorsal surface of the parietal face, width of the horn torus, height of the medial and lateral horn torus, the length and width of the corneal nail caps. We used 181 animals, employed in traction activity in the city of Petrolina (PE), Brazil. There were 56 horses, 97 donkeys and 28 mules, among males and females with different body weights and different ages. The results were tabulated and they can be used to determine the anatomical pattern of these animals in that region. It was possible to verify the practices to which the animals are subjected, like trimming, shoeing and excess load, which can result in poor load distribution on the limbs and nail capsule, generating locomotor disorders. We observed the medial-lateral imbalance of nail capsule, since the medial corneal torus was greater than the lateral one, triggering changes in poise and damaging dynamic and orthostatic positions, which could be solved by trimming and shoeing practices, reducing diseases of the locomotor apparatus.

  10. Mercury uptake and accumulation by four species of aquatic plants

    International Nuclear Information System (INIS)

    The effectiveness of four aquatic plants including water hyacinth (Eichornia crassipes), water lettuce (Pistia stratiotes), zebra rush (Scirpus tabernaemontani) and taro (Colocasia esculenta) were evaluated for their capabilities in removing mercury from water. The plants were exposed to concentrations of 0 mg/L, 0.5 mg/L or 2 mg/L of mercury for 30 days. Assays were conducted using both Microtox[reg] (water) and cold vapor Atomic Absorption Spectroscopy (AAS) (roots and water). The Microtox[reg] results indicated that the mercury induced acute toxicity had been removed from the water. AAS confirmed an increase of mercury within the plant root tissue and a corresponding decrease of mercury in the water. All species of plants appeared to reduce mercury concentrations in the water via root uptake and accumulation. Water lettuce and water hyacinth appeared to be the most effective, followed by taro and zebra rush, respectively. - Four species of aquatic plants reduced mercury in water

  11. Mercury uptake and accumulation by four species of aquatic plants

    Energy Technology Data Exchange (ETDEWEB)

    Skinner, Kathleen [Department of Biology, Russell Sage College, 45 Ferry Street, Troy, NY 12180 (United States)]. E-mail: skinnk@sage.edu; Wright, Nicole [NEIWPCC-NYSDEC, 625 Broadway, 4th Floor, Albany, NY 12233-3502 (United States)]. E-mail: ndwright@gw.dec.state.ny.us; Porter-Goff, Emily [Department of Biology, Russell Sage College, 45 Ferry Street, Troy, NY 12180 (United States)

    2007-01-15

    The effectiveness of four aquatic plants including water hyacinth (Eichornia crassipes), water lettuce (Pistia stratiotes), zebra rush (Scirpus tabernaemontani) and taro (Colocasia esculenta) were evaluated for their capabilities in removing mercury from water. The plants were exposed to concentrations of 0 mg/L, 0.5 mg/L or 2 mg/L of mercury for 30 days. Assays were conducted using both Microtox[reg] (water) and cold vapor Atomic Absorption Spectroscopy (AAS) (roots and water). The Microtox[reg] results indicated that the mercury induced acute toxicity had been removed from the water. AAS confirmed an increase of mercury within the plant root tissue and a corresponding decrease of mercury in the water. All species of plants appeared to reduce mercury concentrations in the water via root uptake and accumulation. Water lettuce and water hyacinth appeared to be the most effective, followed by taro and zebra rush, respectively. - Four species of aquatic plants reduced mercury in water.

  12. 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. PMID:25512846

  13. Spike timing and the coding of naturalistic sounds in a central auditory area of songbirds

    CERN Document Server

    Wright, B D; Bialek, W; Doupe, A J; Wright, Brian D.; Sen, Kamal; Bialek, William; Doupe, Allison J.

    2002-01-01

    In nature, animals encounter high dimensional sensory stimuli that have complex statistical and dynamical structure. Attempts to study the neural coding of these natural signals face challenges both in the selection of the signal ensemble and in the analysis of the resulting neural responses. For zebra finches, naturalistic stimuli can be defined as sounds that they encounter in a colony of conspecific birds. We assembled an ensemble of these sounds by recording groups of 10-40 zebra finches, and then analyzed the response of single neurons in the songbird central auditory area (field L) to continuous playback of long segments from this ensemble. Following methods developed in the fly visual system, we measured the information that spike trains provide about the acoustic stimulus without any assumptions about which features of the stimulus are relevant. Preliminary results indicate that large amounts of information are carried by spike timing, with roughly half of the information accessible only at time resol...

  14. A position sensitive detector using a NaI(Tl)/photomultiplier tube combination for the energy range 200 keV to 10 MeV

    International Nuclear Information System (INIS)

    The performance of the position sensitive detector for the ZEBRA low energy gamma-ray imaging telescope is described. The detector consists of 9 position sensitive NaI(Tl) elements each 5.8x5.0x56.0 cm viewed at either end of the long axis by 2 in. photomultiplier tubes. The total active area is 2470 cm2 with an average positional resolution of 2.1 cm and energy resolution of 15% FWHM at 661.6 keV. The method of flight calibration is described together with the provision within the on-board electronics to correct for sources of error in the calculation of event energy loss and position. The results presented are obtained from the calibration phase of the ZEBRA telescope project. (orig.)

  15. Comparison of measured neutron reaction rates in fast reactor steels with calculated values using FD5 data

    International Nuclear Information System (INIS)

    Measurements were made in three Zebra assemblies of the gamma activity of typical fast power reactor steel components. As a result of corrosion, these become important contributors to the activity of the primary coolant circuit during shut-down. Reaction rates were determined by dissolving irradiated samples and presenting them to a calibrated Ge-Li spectrometer and were expressed relative to Pu239 fission rates in positions near the samples. Calculated values for the reaction-rate ratios were obtained using fluxes from standard Zebra calculations together with the activation cross-sections recommended for power reactor use. Measured and calculated reaction-rate ratios are compared for all the activities, and bias factors with uncertainties of less than 10% produced for the more important contributions to the steel activation. Calculated spectra in the 37-group FD5 structure are presented to allow any new activation cross-section data to be tested against the measured reaction rates. (U.K.)

  16. Toxicogenomic analysis of environmental impact in aquatic systems

    OpenAIRE

    Navarro Cuenca, Anna

    2012-01-01

    Field biomonitoring based on molecular biomarkers detects early warning signals of stress suffered by organisms exposed to contamination. The lower part of the Ebro River basin has a long pollution history related to the presence of a chlor-alkali plant adjacent to Flix. In addition, the Ebro River has been affected by the invasion of alien species that damage its natural ecosystem. In this thesis, Cyprinus carpio (common carp) an Dreissena polymorpha (zebra mussel) were used as a model speci...

  17. Myosin VIIA Defects, which Underlie the Usher 1B Syndrome in Humans, Lead to Deafness in Drosophila

    OpenAIRE

    Todi, Sokol V.; Franke, Josef D.; Kiehart, Daniel P.; Eberl, Daniel F.

    2005-01-01

    In vertebrates, auditory and vestibular transduction occurs on apical projections (stereocilia) of specialized cells (hair cells). Mutations in myosin VIIA (myo-VIIA), an unconventional myosin, lead to deafness and balance anomalies in humans, mice, and zebra-fish; individuals are deaf, and stereocilia are disorganized [1–3]. The exact mechanism through which myo-VIIA mutations result in these inner-ear anomalies is unknown. Proposed inner-ear functions for myoVIIA include anchoring transdu...

  18. Shark Cart

    Science.gov (United States)

    Aquarium of the Pacific

    2009-01-01

    In this activity, learners touch and observe skulls of sharks and rays to learn about their diversity (over 400 species of sharks alone!). Background information is provided about the types and functions of shark teeth. Additional information is provided about specific types of sharks: Great White, Bull Shark, Mako Shark, Zebra Shark, and Rays. The goal of the activity is to make sharks better understood and appreciated.

  19. Regime shift from phytoplankton to macrophyte dominance in a large river: Top-down versus bottom-up effects

    International Nuclear Information System (INIS)

    The lower Ebro River (Catalonia, Spain) has recently undergone a regime shift from a phytoplankton-dominated to a macrophyte-dominated system. This shift is well known in shallow lakes but apparently it has never been documented in rivers. Two initial hypotheses to explain the collapse of the phytoplankton were considered: a) the diminution of nutrients (bottom-up); b) the filtering effect due to the colonization of the zebra mussel (top-down). Data on water quality, hydrology and biological communities (phytoplankton, macrophytes and zebra mussel) was obtained both from existing data sets and new surveys. Results clearly indicate that the decrease in phosphorus is the main cause of a dramatic decrease in chlorophyll and large increase in water transparency, triggering the subsequent colonization of macrophytes in the river bed. A Generalized Linear Model analysis showed that the decrease in dissolved phosphorus had a relative importance 14 times higher than the increase in zebra mussel density to explain the variation of total chlorophyll. We suggest that the described changes in the lower Ebro River can be considered a novel ecosystem shift. This shift is triggering remarkable changes in the biological communities beyond the decrease of phytoplankton and the proliferation of macrophytes, such as massive colonization of Simulidae (black fly) and other changes in the benthic invertebrate communities that are currently investigated. - Highlights: ? We show a regime sated. - Highlights: ? We show a regime shift in a large river from phytoplankton to macrophyte dominance. ? Two main hypotheses are considered: nutrient decrease and zebra mussel grazing. ? Phosphorus depletion is found to be the main cause of the phytoplankton decline. ? We conclude that oligotrophication triggered the colonization of macrophytes. ? This new regime shift in a river is similar to that described in shallow lakes.

  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

    Sedlá?ek, O.; Mikeš, M.; Albrecht, Tomáš; Reif, J.; Ho?ák, D.

    2014-01-01

    Ro?. 7, ?. 4 (2014), s. 720-732. ISSN 1940-0829 R&D Projects: GA ?R(CZ) GAP505/11/1617 Institutional support: RVO:68081766 Keywords : Artificial nests * Zebra finch eggs * Montane forest * Endemic species * Cameroon Mountains Subject RIV: EG - Zoology Impact factor: 1.329, year: 2013 http://tropicalconservationscience.mongabay.com/content/v7/TCS-2014-Vol7(4)_720-732_%20Ondrej.pdf

  1. Living with Wildlife: Coexistence of Wildlife and Livestock in an East African Savanna System

    OpenAIRE

    Voeten, M. M.

    1999-01-01

    This thesis has as its main theme the coexistence of wildlife and livestock in East African savannas. First however, the group size of native herbivore species was related to their body mass, feeding style, habitat choice and density. Body mass explained most variation in group size because of its relation to food requirements and how different sized animals experience the distribution of food. Differential use of (food)resources by Zebu-cattle, wildebeest and zebra was then investigated. The...

  2. Mechanism for Specificity by HMG-1 in Enhanceosome Assembly

    OpenAIRE

    Ellwood, Katharine B.; Yen, Yi-meng; Johnson, Reid C.; Carey, Michael

    2000-01-01

    Assembly of enhanceosomes requires architectural proteins to facilitate the DNA conformational changes accompanying cooperative binding of activators to a regulatory sequence. The architectural protein HMG-1 has been proposed to bind DNA in a sequence-independent manner, yet, paradoxically, it facilitates specific DNA binding reactions in vitro. To investigate the mechanism of specificity we explored the effect of HMG-1 on binding of the Epstein-Barr virus activator ZEBRA to a natural respons...

  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

    OpenAIRE

    Halley, Yvette A.; Dowd, Scot E.; Decker, Jared E.; Seabury, Paul M.; Bhattarai, Eric; Johnson, Charles D.; Rollins, Dale; Tizard, Ian R.; Brightsmith, Donald J.; Peterson, Markus J.; Taylor, Jeremy F.; Seabury, Christopher M.

    2014-01-01

    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...

  4. Reflections on the relationships between communities and conservation areas of South Africa: the case of five South African national parks

    OpenAIRE

    Knight, M. H.; Kerley, G. I. H.; Simelane, T. S.

    2006-01-01

    An evaluation of the relationships between communities around Addo Elephant National Park, Mountain Zebra National Park, Karoo National Park, Golden Gate Highlands National Park and Vaalbos National Park shows that these communities have limited ecological knowledge and understanding of resources occurring within the parks. People within these communities rate relationships with their neighbouring parks as relatively poor. Despite this, these communities are keen to support conservation and ...

  5. Nestling activity levels during begging behaviour predicts activity level and body mass in adulthood

    OpenAIRE

    Mccowan, Luke S. C.; Griffith, Simon C.

    2014-01-01

    Across a range of species including humans, personality traits, or differences in behaviour between individuals that are consistent over time, have been demonstrated. However, few studies have measured whether these consistent differences are evident in very young animals, and whether they persist over an individual’s entire lifespan. Here we investigated the begging behaviour of very young cross-fostered zebra finch nestlings and the relationship between that and adult activity levels. We ...

  6. Latherin: A Surfactant Protein of Horse Sweat and Saliva

    OpenAIRE

    Mcdonald, R. E.; Fleming, R. I.; Beeley, J. G.; Bovell, D. L.; Lu, J. R.; Zhao, X.; Cooper, A.; Kennedy, M. W.

    2009-01-01

    Horses are unusual in producing protein-rich sweat for thermoregulation, a major component of which is latherin, a highly surface-active, non-glycosylated protein. The amino acid sequence of latherin, determined from cDNA analysis, is highly conserved across four geographically dispersed equid species (horse, zebra, onager, ass), and is similar to a family of proteins only found previously in the oral cavity and associated tissues of mammals. Latherin produces a significant reduction in water...

  7. Large herbivore population performance and climate in a South African semi-arid savanna

    OpenAIRE

    Seydack, Armin H.; Grant, Cornelia C.; Smit, Izak P.; Vermeulen, Wessel J.; Johan Baard; Nick Zambatis

    2012-01-01

    Long-term population performance trends of eight large herbivore species belonging to groups of disparate foraging styles were studied in the semi-arid savanna of the Kruger National Park, South Africa. Over the past century the number of bulk feeders (buffalo, waterbuck, blue wildebeest and plains zebra) had increased towards comparatively high population densities, whereas population numbers of selectively feeding antelope species (sable antelope, roan antelope, tsessebe and eland) declined...

  8. HVC Neural Sleep Activity Increases With Development and Parallels Nightly Changes in Song Behavior

    OpenAIRE

    Crandall, Shane R.; Adam, Murtaza; Kinnischtzke, Amanda K.; Nick, Teresa A.

    2007-01-01

    Sleep abnormalities are coexpressed with human communication disorders. Recent data from the birdsong system, the best model for human speech, indicate that sleep has a critical role in vocal learning. To understand the neural mechanisms that underlie behavioral changes during sleep, we recorded sleep activity in the song control area HVC longitudinally during song development in zebra finches. We focused on the sensorimotor phase of song learning, when the finch shapes his song behavior towa...

  9. Small guide establishing eco-toxicity of soil and water (In Romanian)

    OpenAIRE

    Crina Laura Mosneang; Cristina, Romeo Teodor

    2014-01-01

    Soil and water ecotoxicity is one of the major concerns with important implications for human and animal life's quality. Consequently, there were appeared many methods to determine the level of environmental pollution, which in the last decade have seen a tremendous development, with the implementation of European and national legislations. The present review is intended to familiarize readers with some indicators of water pollution and soil testing; testing that zebra fish and earthworm ...

  10. Reconstruction of vocal interactions in a group of small songbirds.

    Science.gov (United States)

    Anisimov, Victor N; Herbst, Joshua A; Abramchuk, Andrei N; Latanov, Alexander V; Hahnloser, Richard H R; Vyssotski, Alexei L

    2014-11-01

    The main obstacle for investigating vocal interactions in vertebrates is the difficulty of discriminating individual vocalizations of rapidly moving, sometimes simultaneously vocalizing individuals. We developed a method of recording and analyzing individual vocalizations in free-ranging animals using ultraminiature back-attached sound and acceleration recorders. Our method allows the separation of zebra finch vocalizations irrespective of background noise and the number of vocalizing animals nearby. PMID:25262206

  11. 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-1?-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-1?-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.

  12. In the eye of the beholder: visual mate choice lateralization in a polymorphic songbird

    OpenAIRE

    Templeton, Jennifer J.; Mountjoy, D. James; Pryke, Sarah R.; Griffith, Simon C.

    2012-01-01

    Birds choose mates on the basis of colour, song and body size, but little is known about the mechanisms underlying these mating decisions. Reports that zebra finches prefer to view mates with the right eye during courtship, and that immediate early gene expression associated with courtship behaviour is lateralized in their left hemisphere suggest that visual mate choice itself may be lateralized. To test this hypothesis, we used the Gouldian finch, a polymorphic species in which individuals e...

  13. Replaceable neurons and neurodegenerative disease share depressed UCHL1 levels

    OpenAIRE

    Lombardino, Anthony J.; Li, Xiao-ching; Hertel, Moritz; Nottebohm, Fernando

    2005-01-01

    Might there be systematic differences in gene expression between neurons that undergo spontaneous replacement in the adult brain and those that do not? We first explored this possibility in the high vocal center (HVC) of male zebra finches by using a combination of neuronal tracers, laser capture microdissection, and RNA profiling. HVC has two kinds of projection neurons, one of which continues to be produced and replaced in adulthood. HVC neurons of the replaceable kind showed a consistent a...

  14. Isolation, Primary Structure Characterization and Identification of the Glycosylation Pattern of Recombinant Goldfish Neurolin, a Neuronal Cell Adhesion Protein

    OpenAIRE

    Denzinger, Thomas; Diekmann, Heike; Bruns, Kai; Laessing, Ute; Stu?rmer, Claudia; Przybylski, Michael

    1999-01-01

    Neurolin is a growth-associated cell surface glycoprotein from goldfish and zebra fish which has been shown to be involved in axonal path-finding in the goldfish retina and suggested to function as a receptor for axon guidance molecules. Being a member of the immunoglobulin superfamily of cell adhesion proteins, neurolin consists of five N-terminal extracellular immunoglobulin (Ig)-like domains, a transmembrane and a short cytoplasmatic domain. Repeated injections of polyclonal Fab fragments ...

  15. Deafening drives cell type-specific changes to dendritic spines in a sensorimotor nucleus important to learned vocalizations

    OpenAIRE

    Tschida, Katherine A.; Mooney, Richard

    2012-01-01

    Hearing loss prevents vocal learning and causes learned vocalizations to deteriorate, but how vocalization-related auditory feedback acts on neural circuits that control vocalization remains poorly understood. We deafened adult zebra finches, which rely on auditory feedback to maintain their learned songs, to test the hypothesis that deafening modifies synapses on neurons in a sensorimotor nucleus important to song production. Longitudinal in vivo imaging revealed that deafening selectively d...

  16. Sleep and sensorimotor integration during early vocal learning in a songbird

    OpenAIRE

    Shank, Sylvan S.; Margoliash, Daniel

    2008-01-01

    Behavioural studies widely implicate sleep in memory consolidation in the learning of a broad range of behaviours1-4. During sleep, brain regions are reactivated5,6, and specific patterns of neural activity are replayed7-10, consistent with patterns observed in prior waking behaviour. Birdsong learning is a paradigmatic model system for skill learning11-14. Song development in juvenile zebra finches is characterised by sleep-dependent circadian fluctuations in singing behaviour, with immediat...

  17. Aberrant Splicing of an Alternative Exon in the Drosophila Troponin-T Gene Affects Flight Muscle Development

    OpenAIRE

    Nongthomba, Upendra; Ansari, Maqsood; Thimmaiya, Divesh; Stark, Meg; Sparrow, John

    2007-01-01

    During myofibrillogenesis, many muscle structural proteins assemble to form the highly ordered contractile sarcomere. Mutations in these proteins can lead to dysfunctional muscle and various myopathies. We have analyzed the Drosophila melanogaster troponin T (TnT) up1 mutant that specifically affects the indirect flight muscles (IFM) to explore troponin function during myofibrillogenesis. The up1 muscles lack normal sarcomeres and contain “zebra bodies,” a phenotypic feature of human nema...

  18. Autecology of Limnomysis benedeni Czerniavsky, 1882 (Crustacea: Mysida) in Lake Constance, Southwestern Germany

    OpenAIRE

    Gergs, Rene?; Hanselmann, Almut J.; Eisele, Isabelle; Rothhaupt, Karl-otto

    2008-01-01

    The Ponto-Caspian mysid Limnomysis benedeni was first recorded in Lake Constance in summer 2006, and a stable population developed at the site of discovery. Although this mysid is common in the Rhine and Danube rivers, little is known about its ecology and impact in systems of invasion. We investigated the autecology of L. benedeni in habitat-choice and food experiments. In the habitat-choice experiments, highly structured habitats, i.e., stones covered with zebra mussels (Dreissena polymorph...

  19. Regime shift from phytoplankton to macrophyte dominance in a large river: Top-down versus bottom-up effects

    Energy Technology Data Exchange (ETDEWEB)

    Ibanez, Carles, E-mail: carles.ibanez@irta.cat [IRTA Aquatic Ecosystems, Carretera Poble Nou, Km 5.5, 43540 St. Carles de la Rapita, Catalonia (Spain); Alcaraz, Carles; Caiola, Nuno; Rovira, Albert; Trobajo, Rosa [IRTA Aquatic Ecosystems, Carretera Poble Nou, Km 5.5, 43540 St. Carles de la Rapita, Catalonia (Spain); Alonso, Miguel [United Research Services S.L., Urgell 143, 08036 Barcelona, Catalonia (Spain); Duran, Concha [Confederacion Hidrografica del Ebro, Sagasta 24-26, 50071 Zaragoza, Aragon (Spain); Jimenez, Pere J. [Grup Natura Freixe, Major 56, 43750 Flix, Catalonia (Spain); Munne, Antoni [Agencia Catalana de l' Aigua, Provenca 204-208, 08036 Barcelona, Catalonia (Spain); Prat, Narcis [Departament d' Ecologia, Universitat de Barcelona, Diagonal 645, 08028 Barcelona Catalonia (Spain)

    2012-02-01

    The lower Ebro River (Catalonia, Spain) has recently undergone a regime shift from a phytoplankton-dominated to a macrophyte-dominated system. This shift is well known in shallow lakes but apparently it has never been documented in rivers. Two initial hypotheses to explain the collapse of the phytoplankton were considered: a) the diminution of nutrients (bottom-up); b) the filtering effect due to the colonization of the zebra mussel (top-down). Data on water quality, hydrology and biological communities (phytoplankton, macrophytes and zebra mussel) was obtained both from existing data sets and new surveys. Results clearly indicate that the decrease in phosphorus is the main cause of a dramatic decrease in chlorophyll and large increase in water transparency, triggering the subsequent colonization of macrophytes in the river bed. A Generalized Linear Model analysis showed that the decrease in dissolved phosphorus had a relative importance 14 times higher than the increase in zebra mussel density to explain the variation of total chlorophyll. We suggest that the described changes in the lower Ebro River can be considered a novel ecosystem shift. This shift is triggering remarkable changes in the biological communities beyond the decrease of phytoplankton and the proliferation of macrophytes, such as massive colonization of Simulidae (black fly) and other changes in the benthic invertebrate communities that are currently investigated. - Highlights: Black-Right-Pointing-Pointer We show a regime shift in a large river from phytoplankton to macrophyte dominance. Black-Right-Pointing-Pointer Two main hypotheses are considered: nutrient decrease and zebra mussel grazing. Black-Right-Pointing-Pointer Phosphorus depletion is found to be the main cause of the phytoplankton decline. Black-Right-Pointing-Pointer We conclude that oligotrophication triggered the colonization of macrophytes. Black-Right-Pointing-Pointer This new regime shift in a river is similar to that described in shallow lakes.

  20. The role of Mesogenin1 in the dynamics of movement and differentiation of mesoderm progenitor cells

    OpenAIRE

    Figueira, Ana Margarida Da Silva

    2013-01-01

    A gastrulação é um processo morfogenético onde migrações e rearranjos celulares estabelecem os três folhetos germinativos: endoderme, mesoderme e ectoderme [1-3]. Apesar dos padrões de gastrulação variarem no reino animal, existem quatro tipos de movimentos celulares evolutivamente conservados: epibolia, involução, convergência e extensão. No peixe-zebra, a epibolia termina quando o vitelo fica completamente coberto pela blastoderme. A involução começa aos 50% de epibolia e, ...