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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Neophobia and parental care in collared flycatchers (Ficedula albicollis)

Svedberg, Maja January 2023 (has links)
Parental care can be important especially in passerine birds and can depend on environment, food availability and behaviour. A behaviour that can affect the food supply for the offspring is neophobia, the fear of novel objects. The more fear the bird exhibits the less it visits the nest with food. In my study I aimed to examine neophobia and how it differed based on sex and if offspring number and weight influenced the behaviour. Video recordings of collared flycatchers nest boxes were used to see how the behaviour differed by placing a novel object on the nest box. The behaviours tested were duration of perching, hovering and visit including latency and frequency of visit. The results showed that there was a significant difference between the sexes in duration, latency, and frequency of visit but also duration of perching before and after placing a novel object on the nest box. In addition, my results showed that nestling weight significantly influenced frequency of visit and nestling number influenced duration of visit. The study shows that the collared flycatchers do express neophobia differently based on the sex and the nestling’s weight and number. Future studies could investigate if neophobia is a plastic behaviour and the effects of prolonged exposure to novel objects whichcould change the offspring’s survival chances or even the nestling’s behaviour.
12

Effects of natural gas development on three grassland bird species in CFB Suffield, Alberta, Canada

Hamilton, Laura 06 1900 (has links)
I investigated the effect of energy sector development and introduced crested wheatgrass (Agropyron cristatum) on grassland birds on Canadian Forces Base Suffield. I conducted point counts and mapped breeding territories in 2007 and 2008 for Savannah sparrows (Passerculus sandwichensis), chestnut-collared longspurs (Calcarius ornatus), and Spragues pipits (Anthus spragueii). I found that Savannah sparrows favored areas with taller vegetation, human disturbances and crested wheatgrass in both years. Longspurs used shorter vegetation and in were tolerant of disturbance. Crested wheatgrass was avoided by longspurs in both years. Pipit territories contained similar vegetation to longspurs, were sensitive to disturbance, and avoided placing territories in areas containing crested wheatgrass or trails in both years. Well sites, pipelines and junctions were not avoided by the three species. My research suggests that reducing the number of trails and the spread of crested wheatgrass will increase habitat availability for sensitive species of grassland birds. / Ecology
13

The dynamics of collared peccary dispersion into available range

Supplee, Vashti Crowninshield January 1981 (has links)
No description available.
14

Effects of natural gas development on three grassland bird species in CFB Suffield, Alberta, Canada

Hamilton, Laura Unknown Date
No description available.
15

Competition, Coexistence and Character Displacement : In a Young Avian Hybrid Zone

Vallin, Niclas January 2011 (has links)
This thesis investigates the ecological and evolutionary implications of a recent secondary contact between two closely related bird species: collared (Ficedula albicollis) and pied (F. hypoleuca) flycatchers. Collared flycatchers started to colonize the Swedish island of Öland, where pied flycatchers were already present, in the late 1950s-early1960s. My major aims were to investigate which factors are acting against versus for long-term coexistence between the two species. Specifically, I investigated the relative importance of allopatric divergence, interspecific competition, hybridization and learning in promoting or inhibiting coexistence. The combined effects of interspecific competition and hybridization drives pied flycatchers towards local extinction in their preferred deciduous habitat. However, my results also show that pied flycatchers are better able to tolerate harsh environmental conditions. This trade-off between competitive ability and resilience in the face of harsh conditions facilitates a regional coexistence between the species. Coexistence is furthermore favoured by competition-mediated divergence in breeding habitat choice, timing of breeding and male breeding plumage colouration. Due to interspecific competition, male pied flycatchers are forced to breed in a more mixed forest type with a later peak in food abundance, which is accompanied by a divergence in breeding time between the two species. In areas shared with collared flycatchers, male pied flycatchers with brown plumage coloration, most divergent from that of collared flycatchers, are favoured by selection. In addition to facilitating coexistence, the observed shift in habitat occupancy increases reproductive isolation between the two species. By using cross-fostering experiments I demonstrate that natal habitat imprinting has the potential to additionally speed up habitat segregation. Finally I show that hybrid nestlings express an intermediate response to harsh environments, indicating that another aspect of ecological-based selection may be important in reproductive isolation between the species. In summary, my results show that adaptations during historic allopatry are important both in facilitating coexistence as well as in providing a foundation for further ecological divergence at secondary contact. This is of relevance today as many species are shifting their distributions in response to habitat disturbance and global warming.
16

Ocorrência e detecção molecular de espécies de Mycobacterium, e dos genes de virulência vapA, vapB e VapN em linhagens de Rhodococcus equi, isoladas de linfonodos de taiassuídeos de cativeiro

Morais, Amanda Bonalume Cordeiro de. January 2017 (has links)
Orientador: Márcio Garcia Ribeiro / Resumo: Foram investigadas, neste estudo, proteínas associadas à virulência (genes vapA, vapB e vapN) das espécies de Rhodococcus equi e Micobactérias isoladas de 330 linfonodos de catetos (Tayassu tajacu) e queixadas (Tayassu pecari) destinados ao consumo humano. Trinta e seis (10,9%) linhagens de R. equi foram isoladas, 3,3% (11/330) dos linfonodos de queixadas e 7,6% (25/330) dos catetos. Entre os 11 isolados de R. equi das queixadas, 90,9% (n=10/11) foram obtidos de linfonodos mesentéricos e apenas 9,1% (n=1/10) de linfonodo mediastínico. Nos 25 isolados de R. equi dos catetos, 40,0% (10/25) foram obtidos de linfonodos mesentéricos, 36,0% (9/25) de submandibulares e 24,0% (6/25) de mediastínicos. Não foram identificados genes vapA, vapB e vapN entre os isolados de R. equi. Foi isolado Mycobacterium sp. de 3,03% (10/330) do total de linfonodos. Entre os 10 isolados de micobactérias, 60% (n=6/10) dos linfonodos eram de queixadas e 40% (4/10) de catetos. Dez espécies de Mycobacterium foram detectadas por PCR-PRA, com predominância de M. avium tipo 1. O sequenciamento dos genes hsp65 e rpob revelaram micobactérias saprófitas (M. sinense, M. kumamotonense) e potencialmente patogênicas (M. colombiense, M. intracellulare) para humanos e animais. Esta é a primeira descrição de R. equi e / ou espécies de micobactérias identificadas nos linfonodos de espécimes de Tayassuideos. Apesar da ausência de genes Vap, a identificação de R. equi, bem como de micobactérias não tuberculosas e saprófit... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Virulence-associated proteins (vapA, vapB and vapN genes) of Rhodococcus equi and Mycobacterium species isolated from 330 lymph nodes of collared peccaries (Tayassu tajacu) and white-lipped peccaries (Tayassu pecari) intended for human consumption were investigated. Thirty-six (10.9%) R. equi strains were isolated, 3.3% (11/330) from white-lipped peccary and 7.6% (25/330) of collared peccary lymph nodes. Among the 11 isolates of R. equi of the white-lipped peccaries, 90.9% (n = 10/11) were obtained from mesenteric lymph nodes and only 9.1% (n = 1/10) of the mediastinal lymph node. In the 25 isolates of R. equi obtained from collared peccaries, 40.0% (10/25) were recovered from mesenteric lymph nodes, 36% (9/25) from submandibular, and 24.0% (6/25) from mediastinal ones. No vapA, vapB, and vapN genes (plasmidless type) were identified among R. equi isolates. Mycobacterium sp. was isolated in 3.03% (10/330) of all lymph nodes analyzed. Among the 10 mycobacterial isolates, 60% (n = 6/10) were from white-lipped peccary, and 40% (4/10) from collared peccary lymph nodes. Ten Mycobacterium species were detected by PCR-PRA, with predominance of M. avium type 1. Sequencing of hsp65 and rpob genes revealed mycobacteria that were saprophytic (M. sinense, M. kumamotonense) and potentially pathogenic (M. colombiense, M. intracellulare) to humans and animals. To our knowledge, this is the first description of R. equi and/or mycobacteria species identified in the lymph nodes of Tayassuid sp... (Complete abstract click electronic access below) / Doutor
17

Determinação da concentração alveolar mínima (CAM) do sevofluorano em catetos (Tayassu tajacu) / Determination of the minimum alveolar concentration (MAC) of sevoflurane in collared peccaries (Tayassu tajacu)

Morais, Alessandro Magno Lustosa de 08 August 2013 (has links)
Made available in DSpace on 2016-08-15T20:31:30Z (GMT). No. of bitstreams: 1 AlessandroMLM_DISSERT.pdf: 5295776 bytes, checksum: 660aceb095a002197fe2c4cf31191b3e (MD5) Previous issue date: 2013-08-08 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Inhaled anesthesia is a widely used technique in the different domestic animal species; however it is little studied in wild animals. The aim of this study was to determine the minimum alveolar concentration (MAC) of sevoflurane (SEVO) in peccaries (Tayassu tajacu), investigate its effects on physiological (heart and respiratory rates, temperature and blood pressure) and blood gas analysis as long as the quality of anesthesia recovery time. Ten adult male peccaries weighting 22.4 ± 1.31 kg were used. MAC determination was obtained through intentional motor response evaluated after supramaximal noxious stimuli by clamping the interdigital space. A positive or negative response to the stimulus was recorded, and ET SEVO then increased (if positive response) or decreased (if negative response) by 10%. Individual MAC was the average of multiple determinations. Physiological parameters and blood gas analysis at different times (before induction of anesthesia, to a concentration of 6%, after MAC determination, at MAC, and after extubation 1.5 MAC) were analyzed by analysis of variance (One Way RM ANOVA) for repeated measures followed by Tukey, the degree of significance of 5% (p <0,05). The MAC of sevoflurane for collared peccaries was determined as 4.26 ± 0.68% with the animals fully recovered at 32,0 ± 9,70 minutes. It was concluded by this study that the MAC for SEVO is similar to recent values reported for pigs, with fully short recovery time, but higher than general values reported for other species / A anestesia inalatória é uma técnica utilizada em diferentes espécies animais domésticas, no entanto pouco estudada em algumas espécies silvestres. Este estudo teve como objetivo determinar a concentração alveolar mínima (CAM) do sevofluorano em catetos (Tayassu tajacu), investigar seus efeitos nos parâmetros fisiológicos (frequências cardíaca e respiratória, temperatura e pressão arterial) e hemogasométricos além do tempo e a qualidade da recuperação anestésica. Foram utilizados dez catetos machos, adultos, hígidos, pesando 22.4 ± 1.31 kg. A determinação da CAM foi obtida através da resposta motora intencional avaliada após estímulos nociceptivos supramáximos pelo pinçamento do espaço interdigital. De acordo com as respostas obtidas (positivas ou negativas), a concentração foi aumentada ou diminuída em 10%. A média aritmética entre as concentrações do agente inalatório (com e sem resposta) foi utilizada na determinação da concentração alveolar mínima para esta espécie. Os parâmetros fisiológicos e hemogasométricos nos diferentes momentos (antes da indução da anestesia, a uma concentração de 6%, após a determinação da CAM, após 1,5 CAM e à extubação) foram analisados por analise de variância (One way ANOVA RM) para medidas repetidas seguidas por Tukey, sendo o grau de significância de 5% (p<0,05). A CAM de sevofluorano para catetos foi determinada em 4,26 ± 0,68%, com os animais se recuperando totalmente aos 32,0 ± 9,70 minutos. Concluiu-se neste estudo que a CAM para SEVO é semelhante aos valores recentes relatados para suínos com ótima qualidade da recuperação e curto tempo, porém maiores que os valores relatados para outras espécies
18

Ocorrência e detecção molecular de espécies de Mycobacterium, e dos genes de virulência vapA, vapB e VapN em linhagens de Rhodococcus equi, isoladas de linfonodos de taiassuídeos de cativeiro / Occurrence and molecular detection of Mycobacterium species, and the virulence-associated proteins (vapA, vapB and vapN genes) in strains of Rhodococcus equi, isolated from the lymph nodes of captive Tayassuidae species

Morais, Amanda Bonalume Cordeiro de [UNESP] 14 July 2017 (has links)
Submitted by AMANDA BONALUME CORDEIRO DE MORAIS null (amandabonalume@gmail.com) on 2017-08-26T23:21:44Z No. of bitstreams: 1 Tese de Doutorado - Amanda Bonalume Cordeiro de Morais.pdf: 1450434 bytes, checksum: f33cf08ef7c061d673fbb609f96c4bb3 (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-08-29T14:13:48Z (GMT) No. of bitstreams: 1 morais_abc_dr_bot.pdf: 1450434 bytes, checksum: f33cf08ef7c061d673fbb609f96c4bb3 (MD5) / Made available in DSpace on 2017-08-29T14:13:48Z (GMT). No. of bitstreams: 1 morais_abc_dr_bot.pdf: 1450434 bytes, checksum: f33cf08ef7c061d673fbb609f96c4bb3 (MD5) Previous issue date: 2017-07-14 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Foram investigadas, neste estudo, proteínas associadas à virulência (genes vapA, vapB e vapN) das espécies de Rhodococcus equi e Micobactérias isoladas de 330 linfonodos de catetos (Tayassu tajacu) e queixadas (Tayassu pecari) destinados ao consumo humano. Trinta e seis (10,9%) linhagens de R. equi foram isoladas, 3,3% (11/330) dos linfonodos de queixadas e 7,6% (25/330) dos catetos. Entre os 11 isolados de R. equi das queixadas, 90,9% (n=10/11) foram obtidos de linfonodos mesentéricos e apenas 9,1% (n=1/10) de linfonodo mediastínico. Nos 25 isolados de R. equi dos catetos, 40,0% (10/25) foram obtidos de linfonodos mesentéricos, 36,0% (9/25) de submandibulares e 24,0% (6/25) de mediastínicos. Não foram identificados genes vapA, vapB e vapN entre os isolados de R. equi. Foi isolado Mycobacterium sp. de 3,03% (10/330) do total de linfonodos. Entre os 10 isolados de micobactérias, 60% (n=6/10) dos linfonodos eram de queixadas e 40% (4/10) de catetos. Dez espécies de Mycobacterium foram detectadas por PCR-PRA, com predominância de M. avium tipo 1. O sequenciamento dos genes hsp65 e rpob revelaram micobactérias saprófitas (M. sinense, M. kumamotonense) e potencialmente patogênicas (M. colombiense, M. intracellulare) para humanos e animais. Esta é a primeira descrição de R. equi e / ou espécies de micobactérias identificadas nos linfonodos de espécimes de Tayassuideos. Apesar da ausência de genes Vap, a identificação de R. equi, bem como de micobactérias não tuberculosas e saprófitas, destacam o risco de transmissão desses patógenos das espécies de Tayassuideos para humanos por meio de carne ou produtos à base de carne contaminados com conteúdo de linfonodos, uma vez que R. equi sem plasmídeo de virulência e as espécies de micbactérias descritas aqui já foram relatadas como causas de infecções pulmonares e extrapulmonares em seres humanos imunocompetentes e imunocomprometidos. / Virulence-associated proteins (vapA, vapB and vapN genes) of Rhodococcus equi and Mycobacterium species isolated from 330 lymph nodes of collared peccaries (Tayassu tajacu) and white-lipped peccaries (Tayassu pecari) intended for human consumption were investigated. Thirty-six (10.9%) R. equi strains were isolated, 3.3% (11/330) from white-lipped peccary and 7.6% (25/330) of collared peccary lymph nodes. Among the 11 isolates of R. equi of the white-lipped peccaries, 90.9% (n = 10/11) were obtained from mesenteric lymph nodes and only 9.1% (n = 1/10) of the mediastinal lymph node. In the 25 isolates of R. equi obtained from collared peccaries, 40.0% (10/25) were recovered from mesenteric lymph nodes, 36% (9/25) from submandibular, and 24.0% (6/25) from mediastinal ones. No vapA, vapB, and vapN genes (plasmidless type) were identified among R. equi isolates. Mycobacterium sp. was isolated in 3.03% (10/330) of all lymph nodes analyzed. Among the 10 mycobacterial isolates, 60% (n = 6/10) were from white-lipped peccary, and 40% (4/10) from collared peccary lymph nodes. Ten Mycobacterium species were detected by PCR-PRA, with predominance of M. avium type 1. Sequencing of hsp65 and rpob genes revealed mycobacteria that were saprophytic (M. sinense, M. kumamotonense) and potentially pathogenic (M. colombiense, M. intracellulare) to humans and animals. To our knowledge, this is the first description of R. equi and/or mycobacteria species identified in the lymph nodes of Tayassuid specimens. Despite the absence of Vap genes, the identification of R. equi, as well as nontuberculous and saprophytic mycobacteria highlight the risk of transmission of these pathogens from Tayassuidae species to humans by means of meat or meat products contaminated with lymph node contents, since R. equi plasmidless type and mycobacterial species described here have been reported as causes of pulmonary and extrapulmonary infections both in immunocompetent and immunocompromised humans.
19

Excavation of Barrow III, Irton Moor, North Yorkshire.

Simpson, D.D.A., Gibson, Alex M., Malazarte-Smith, G., Keepax, C., Limbrey, S. 05 August 2015 (has links)
Yes / Irton Moor was excavated by Derek Simpson in 1973 but remained unpublished at the time of his death in 2006. Material from the excavation including a skeletal report and some publication drawings were located in DDAS’s archives and brought back to Bradford for archiving. Sufficient work had been done by DDAS to bring the report to publication though clearly the archive had suffered over the years. Irton Moor represents a small structured round cairn of the Early Bronze Age producing evidence for long-term occupation of the site from the Early Neolithic though this occupation does not appear to have been continuous. The cairn was used for Food Vessel and Collared Urn-associated cremations.
20

Determinants of genomic diversity in the collared flycatcher (Ficedula albicollis)

Dutoit, Ludovic January 2017 (has links)
Individuals vary from each other in their genetic content. Genetic diversity is at the core of the evolutionary theory. Rooted in a solid theoretical framework developed as early as the 1930s, current empirical observations of genomic diversity became possible due to technological advances. These measurements, originally based on a few gene sequences from several individuals, are becoming possible at the genome scale for entire populations. We can now explore how evolutionary forces shape diversity levels along different parts of the genome. In this thesis, I focus on the variation in levels of diversity within genomes using avian systems and in particular that of the collared flycatcher (Ficedula albicollis). First, I describe the variation in genetic diversity along the genome of the collared flycatcher and compare it to the amount of variation in diversity across individuals within the population. I provide guidelines on how a small number of makers can capture the extent of variability in a population. Second, I investigate the stability of the local levels of diversity in the genome across evolutionary time scales by comparing collared flycatcher to the hooded crow (Corvus (corone) corone). Third, I study how selection can maintain variation through pervasive evolutionary conflict between sexes. Lastly, I explore how shifts in genome-wide variant frequencies across few generations can be utilised to estimate the effective size of population.

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