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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.
1

Cytological studies of Dileptus anser

Hayes, Merlin Lewis, January 1935 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1935. / Typescript. Includes abstract and vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves i-ii).
2

Phylogeography and conservation genetics of the lesser white-fronted goose (<em>Anser erythropus</em>)

Ruokonen, M. (Minna) 28 March 2001 (has links)
Abstract Analyses of mitochondrial control region sequences were used to infer phylogeny of Anser species, phylogeography of the lesser white-fronted goose, and genetic background of a captive stock. The genetic distances among the Anser species ranged from 0.9 to 5.5% in the complete control region sequences and supported the view of close relatedness of these species. Among the four most closely related species, the bean, pink-footed, white-fronted and lesser white-fronted goose, the branching order is uncertain. The short internal branches and low support for the branching order suggest that the species have diverged recently within short time-intervals. The mtDNA tree obtained is incongruent with the traditional view of the species relationships, but the reasons for this remain to be clarified. Two diverged mitochondrial lineages were found in the lesser white-fronted goose and a refugial origin was proposed. Basal haplotypes are geographically widespread and indicate a recent common ancestry for populations. The derived haplotypes are confined to singular breeding populations and suggest restrictions to the present female gene flow. A shift in the frequency of the mtDNA lineages approximately coincides with a migratory divide in the Taimyr Peninsula. Low mtDNA diversity and significant difference in the haplotype frequencies observed in Fennoscandian subpopulation suggested that it should be considered as a management unit. The fossil record was examined to gain additional information about the colonisation history of the species, but was found to be of limited use. The captive lesser white-fronted goose stock used for reintroduction/restocking was shown to be incompatible with the Fennoscandian wild population. Some captive individuals carried the mtDNA of the white-fronted goose suggesting a hybrid origin. Hybridisation has probably occurred during captive propagation, but to clarify further the extent of introgression, nuclear markers should be applied. The structure and evolution of the control region were studied by comparing complete avian sequences. Saturation was found to occur at pairwise divergences of 10% as shown for third codon positions of the mitochondrial genes previously. In pairwise comparisons of the control region and cytochrome b sequences, the rate of divergence varied among the lineages. Two conserved sequence blocks showed considerable sequence conservation when compared to mammalian sequences.
3

The domestication history of the European goose:a genomic perspective

Heikkinen, M. (Marja) 09 June 2017 (has links)
Abstract Animal domestication is a complex evolutionary process. Multiple forces influence the genetic variation of the species under domestication and leave their mark on the genome of the species. The European domestic goose is an economically and culturally important species, but knowledge about the domestication history of the species has been lacking. My doctoral thesis has focused on elucidating the genetic background of goose domestication using mitochondrial control region sequences and nuclear single nucleotide polymorphisms (SNPs). By comparing the patterns of genetic diversity observed in the greylag goose (Anser anser) and its descendant European domestic geese, I was able to conclude that genetic diversity has decreased in domestic geese following the domestication albeit being still relatively high. In addition, admixture of populations increased the genetic diversity in both greylag geese and domestic geese. The results also confirmed that greylag geese and domestic geese hybridise in certain locations. What is more, many breeds of European domestic geese shared a substantial amount of ancestry with Chinese domestic geese, domesticated from the swan goose (Anser cygnoid). While the timing and location of goose domestication remains unresolved, the results do not disagree with the suggested origin of domestication in the Eastern Mediterranean. More sampling in this region would be needed to further investigate the matter. Lastly, multiple regions in the goose genome have been targeted by selection which is likely to have contributed to phenotypic divergence of greylag and domestic geese, but the functional basis of these differences needs further investigation. / Tiivistelmä Eläinlajin kesyttäminen on monimutkainen evolutiivinen prosessi. Useat geneettiset tekijät vaikuttavat kesytettävän lajin perinnöllisen monimuotoisuuden määrään ja jättävät lajin perimään jälkensä. Eurooppalainen kesyhanhi on kulttuurillisesti ja taloudellisesti merkittävä laji, mutta tieto sen kesytyshistoriasta on puutteellista. Väitöskirjassani olen keskittynyt tutkimaan hanhen kesytyksen perinnöllistä taustaa käyttäen apuna mitokondrio-DNA:n kontrollialueen sekvenssejä ja yhden emäksen polymorfismeja. Kun vertailin perinnöllisen monimuotoisuuden jakautumista merihanhissa (Anser anser) ja eurooppalaisissa kesyhanhissa, pystyin toteamaan, että perinnöllinen monimuotoisuus on kesytyksen seurauksena vähentynyt kesyhanhissa, mutta se on edelleen suhteellisen korkeaa. Lisäksi risteytyminen muiden populaatioiden kanssa lisäsi perinnöllistä monimuotoisuutta sekä meri- että kesyhanhissa. Tulokset myös vahvistivat, että meri- ja kesyhanhet risteytyvät paikoitellen keskenään. Tämän lisäksi moniin eurooppalaisiin kesyhanhirotuihin on kohdistunut geenivirtaa kiinalaisesta kesyhanhesta, joka on kesytetty joutsenhanhesta (Anser cygnoid). Saadut tulokset vastaavat aiempia näkemyksiä, joiden mukaan hanhi kesytettiin Välimeren idänpuoleisilla alueilla, kanssa, mutta kesytyksen ajankohdan ja paikan tarkempi selvittäminen vaatii vielä lisätutkimuksia ja lisää näytteitä tältä alueelta. Lopuksi voidaan todeta, että useat alueet hanhen perimässä osoittivat merkkejä valinnasta, joka on todennäköisesti vaikuttanut meri- ja kesyhanhien välisiin fenotyyppisiin eroihin, mutta erojen funktionaalinen tausta vaatii lisätutkimuksia.
4

The Greenland White-fronted goose Anser albifrons flavirostris : the annual cycle of a migratory herbivore on the European continental fringe /

Fox, Anthony David. January 2003 (has links)
Thesis (DSc.)--National Environmental Research Institute, Denmark. / Includes bibliographical referen.
5

Estudo de parâmetros clínicos, imunitários e do proteinograma sérico da vacinação contra a doença de Newcastle em gansos-da-China (Anser cygnoides): pesquisa do estado portador do vírus e sua importância epidemiológica

Campioni, Josie Maria [UNESP] 05 June 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-06-05Bitstream added on 2014-06-13T19:57:06Z : No. of bitstreams: 1 campioni_jm_me_jabo.pdf: 299949 bytes, checksum: f61e757f800c01b36b0ae99a0fbe3f0f (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Parâmetros clínicos, imunitários, proteinograma sérico e epidemiológicos da vacinação em gansos-da-China foram avaliados por três experimentos. Amostras vacinais Ulster 2C, B1 e La Sota do VDN foram utilizadas. A importância epidemiológica e pesquisa do estado de portador do VDN também foram avaliadas. No experimento 1, foram utilizados 120 gansos-da-China de um dia a 60 dias de idade, distribuídos em 4 tratamentos com 30 animais, submetidos a diferentes esquemas imunoprofiláticos. Os resultados dos títulos de anticorpos (HI) mostraram que os programas imunoprofiláticos ensaiados foram igualmente eficientes no estímulo da resposta imune humoral. Após o desafio frente a uma estirpe patogênica do VDN, aos 60 dias de vida das aves, em todos os grupos, realizou-se a extração de RNA viral através da reação de cadeia de polimerase pós Transcrição Reversa (RT-PCR). No experimento 2, foram utilizadas aves SPF conviventes com gansos-da-China inoculados com uma estirpe patogênica do VDN, decorridos seis, 10 e 20 dias da infecção experimental, após a infecção com o VDN, nas duas espécies, empregou-se a técnica do RT-PCR. Observou-se a transmissão de vírus patogênico (VDN) dos gansos-da- China para as aves SPF conviventes decorridos até 14 dias da infecção experimental com este patógeno, o que vem realçar a importância do ganso-da-China como fonte potencial de infecção de VDN para aves domésticas No experimento 3, foram determinadas as concentrações séricas das proteínas totais, albumina e globulinas das aves vacinadas e não vacinadas contra a doença de Newcastle. Notou-se que aos 42 dias de idade, de forma geral, os gansos vacinados com as estirpes Ulster 2C, B1 e Lasota apresentaram diferença de forma significativa em relação ao grupo controle para as concentrações séricas de albumina, especialmente o grupo vacinado com a estirpe LaSota. / The clinical, epidemiological, immunological parameters and the serum proteinogram of vaccination in Chinese geese were investigated using 3 experiments. Ulster 2C, B1 and LaSota vaccines strains of the NDV were used. In experiment 1, 120 one-day-old Chinese geese were used, and divided into 4 different groups with 30 birds per group. They were submitted to different vaccination programs. The immunological responses in these birds were measured by HI test. These birds were also challenged with a pathogenic VDN strain at 60 days of age. After challenge, in all the groups, tracheal and cloacal swabs were collected for RT-PCR. Independent of the group, clinical signs of reaction to the vaccine were not observed. The antibody titers (HI) results showed that the immune vaccine programs adopted were equally efficient in stimulating protective levels of humoral immune responses. Challenged Chinese geese were refractory to the NDV clinical disease. However, a NDV carrier state was shown in this species until 20 days after experimental infection. The vaccinated groups of Chinese geese did not present any genetic material of virus in the RT-PCR. Therefore, these results show the relevance of vaccination in suppressing a NDV carrier state in the Chinese geese. In experiment 2, SPF chickens housed with Chinese geese which were previously inoculated with a pathogenic NDV strain, developed severe and characteristic NDV lesions and died, after five and 14 days. In experiment 3, the serum proteinogram showed significantly differences for albumin concentrations between the vaccinated and the control group at 42 days of age, especially the birds vaccinated with LaSota strain.
6

Habitat selection and movements of Taiga Bean Geese Anser fabalis fabalis during spring and early summer

Vahlström, Isak January 2017 (has links)
Habitats vary in terms of food and predation risk between each other and over time. The aim of this study was to describe the daily cycle of habitat selection and movements of Taiga Bean Geese Anser fabalis fabalis during spring and early summer. For that I used data from 11 Taiga Bean Geese marked with GPS-transmitters in Vilhelmina county, Sweden. I coded every position to a habitat and calculated length of movements between the positions. In most cases the geese spent the night at wetlands and agricultural fields, probably feeding, and the day close to lakes and streams, probably resting. The geese moved between those habitats in the morning and in the evening. These movements between habitats are more likely due to change in predation pressure than resource depletion of the first habitat.
7

Aspects non-canalisés de la dynamique de population de la grande oie des neiges : probabilités de reproduction et de survie juvénile / Non-canalized aspects of population dynamics of greater snow goose : juvenile survival and reproduction probabilities

Souchay, Guillaume 13 March 2013 (has links)
Chez les espèces longévives, une relation inverse entre la variabilité des paramètres démographiques et leur élasticité (i.e. la contribution relative du paramètre au taux de croissance de la population) semble exister. La théorie de la canalisation environnementale permet d'expliquer une telle relation. Les paramètres ayant la plus haute élasticité auraient évolué de façon à être moins variable face aux variations environnementales afin d'optimiser la fitness individuelle et ainsi maximiser la croissance de la population. Afin de tester l'existence d'une telle hypothèse chez une espèce, il est nécessaire d'estimer les paramètres démographiques ainsi que leur contribution relative au taux de croissance. À l'aide des modèles les plus récents de capture-marquage-recapture, nous avons donc estimé les paramètres de survie juvénile et de reproduction chez la grande oie des neiges pour les comparer au taux de survie adulte, paramètre le plus élastique.Notre étude a montré que les paramètres de survie juvéniles et de probabilité de nicher étaient très variables, tel qu'attendu. Le taux de survie juvénile dépend des conditions environnementales, avec notamment un fort effet du parasitisme. En vermifugeant des individus, nous avons trouvé un effet négatif des parasites intestinaux sur la survie des oies juvéniles femelles mais pas sur celle des mâles, ce qui s'explique probablement par une différence d'investissement dans le système immunitaire en fonction du sexe chez les individus en croissance. La probabilité de nicher est également dépendante des conditions environnementales mais notre étude a également révélé l'existence de coûts associés à la reproduction. En effet, la probabilité de nicher l'année suivante était fortement réduite suite à une reproduction avec succès comparé aux individus qui avaient eu un échec. Par contre, parmi les individus qui nichent, ceux qui avaient du succès l'année précédente avaient plus de chance d'avoir à nouveau du succès l'année suivante que ceux qui avaient eu un échec, ce qui suggère une hétérogénéité dans la qualité des individus. En parallèle de ces estimations, nous avons montré que le taux de survie adulte était constant au cours du temps et indépendante du statut reproducteur l'année précédente. Finalement, nous avons également trouvé que la survie adulte ne différait pas entre 2 colonies situés à 800 km de distance dans l'Arctique canadien, ce qui suggère une absence de variabilité spatiale pour ce paramètre démographique. Notre étude a donc démontré la faible variabilité temporelle et spatiale du paramètre démographique le plus important pour le taux de croissance de la population, contrairement aux autres paramètres qui montrent une forte variabilité chez la grande oie des neiges. Notre étude permet donc d'appuyer la théorie de la canalisation environnementale des paramètres démographiques chez les espèces longévives. / In long-lived species, an inverse relationship apparently occurs between variability of demographic parameters and their elasticity (i.e. the relative contribution of a given parameter to the population growth rate). The environmental canalization theory has been proposed to explain such a relationship. Demographic parameters with the highest elasticity should have evolved in a way reducing their variability in presence of environmental variations in order to optimize individual fitness and hence to maximize the population growth rate.To test this hypothesis in a given species, demographic parameters and their elasticity need to be accurately estimated. Using advanced capture-mark-recapture models, we estimated juvenile survival and breeding probabilities in the greater snow goose and we compared their variability to adult survival, the parameter with the highest elasticity.Our study showed that both juvenile survival rate and breeding propensity were highly variable, as expected. The juvenile survival probability varied upon environmental conditions, with a strong impact of parasitism. An anthelmintic drug treatment applied to juveniles revealed a negative effect of intestinal parasites on survival of juvenile females but not males, which could be explained by a sex-differential investment in the immune system in growing individuals. We found that the breeding propensity also varied with environmental conditions but we also found some evidence for costs of reproduction. Breeding propensity in the following year was greatly reduced after a successful reproduction compared to birds that had a failed attempt. However, among birds that bred, those that had a success the year before were more likely to be successful again the following year than those that had failed, which suggests heterogeneity in individual quality. In those studies, we showed that adult survival was constant over time and independent of the breeding status the year before. Finally, we also found that adult survival did not differ between 2 breeding colonies distant of 800 km in the Canadian Arctic, which suggests an absence of spatial variability for this demographic parameter.We thus demonstrated a low temporal and spatial variability in the most important demographic parameter for population growth, which contrasts with the high variability of other parameters in the greater snow goose. Our study supports the environmental canalization theory as applied to demographic parameters in long-lived species.
8

Estudo de parâmetros clínicos, imunitários e do proteinograma sérico da vacinação contra a doença de Newcastle em gansos-da-China (Anser cygnoides) : pesquisa do estado portador do vírus e sua importância epidemiológica /

Campioni, Josie Maria. January 2009 (has links)
Orientador: Antonio Carlos Paulillo / Banca: Ângela Cleusa de Fátima Banzatto de Carvalho / Banca: Márcia Nishizawa / Resumo: Parâmetros clínicos, imunitários, proteinograma sérico e epidemiológicos da vacinação em gansos-da-China foram avaliados por três experimentos. Amostras vacinais Ulster 2C, B1 e La Sota do VDN foram utilizadas. A importância epidemiológica e pesquisa do estado de portador do VDN também foram avaliadas. No experimento 1, foram utilizados 120 gansos-da-China de um dia a 60 dias de idade, distribuídos em 4 tratamentos com 30 animais, submetidos a diferentes esquemas imunoprofiláticos. Os resultados dos títulos de anticorpos (HI) mostraram que os programas imunoprofiláticos ensaiados foram igualmente eficientes no estímulo da resposta imune humoral. Após o desafio frente a uma estirpe patogênica do VDN, aos 60 dias de vida das aves, em todos os grupos, realizou-se a extração de RNA viral através da reação de cadeia de polimerase pós Transcrição Reversa (RT-PCR). No experimento 2, foram utilizadas aves SPF conviventes com gansos-da-China inoculados com uma estirpe patogênica do VDN, decorridos seis, 10 e 20 dias da infecção experimental, após a infecção com o VDN, nas duas espécies, empregou-se a técnica do RT-PCR. Observou-se a transmissão de vírus patogênico (VDN) dos gansos-da- China para as aves SPF conviventes decorridos até 14 dias da infecção experimental com este patógeno, o que vem realçar a importância do ganso-da-China como fonte potencial de infecção de VDN para aves domésticas No experimento 3, foram determinadas as concentrações séricas das proteínas totais, albumina e globulinas das aves vacinadas e não vacinadas contra a doença de Newcastle. Notou-se que aos 42 dias de idade, de forma geral, os gansos vacinados com as estirpes Ulster 2C, B1 e Lasota apresentaram diferença de forma significativa em relação ao grupo controle para as concentrações séricas de albumina, especialmente o grupo vacinado com a estirpe LaSota. / Abstract: The clinical, epidemiological, immunological parameters and the serum proteinogram of vaccination in Chinese geese were investigated using 3 experiments. Ulster 2C, B1 and LaSota vaccines strains of the NDV were used. In experiment 1, 120 one-day-old Chinese geese were used, and divided into 4 different groups with 30 birds per group. They were submitted to different vaccination programs. The immunological responses in these birds were measured by HI test. These birds were also challenged with a pathogenic VDN strain at 60 days of age. After challenge, in all the groups, tracheal and cloacal swabs were collected for RT-PCR. Independent of the group, clinical signs of reaction to the vaccine were not observed. The antibody titers (HI) results showed that the immune vaccine programs adopted were equally efficient in stimulating protective levels of humoral immune responses. Challenged Chinese geese were refractory to the NDV clinical disease. However, a NDV carrier state was shown in this species until 20 days after experimental infection. The vaccinated groups of Chinese geese did not present any genetic material of virus in the RT-PCR. Therefore, these results show the relevance of vaccination in suppressing a NDV carrier state in the Chinese geese. In experiment 2, SPF chickens housed with Chinese geese which were previously inoculated with a pathogenic NDV strain, developed severe and characteristic NDV lesions and died, after five and 14 days. In experiment 3, the serum proteinogram showed significantly differences for albumin concentrations between the vaccinated and the control group at 42 days of age, especially the birds vaccinated with LaSota strain. / Mestre
9

Muster der Raumnutzung markierter Blessgänse (Anser albifrons albifrons) in West- und Mitteleuropa unter Berücksichtung sozialer Aspekte

Kruckenberg, Helmut 24 April 2003 (has links)
Die Europäische Blessgans ist die häufigste arktische Gänseart, die in Westeuropa überwintert. Seit 1998 wurden in einem internationalen Farbmarkierungsprojekt 3740 Blessgänse mit individuell codierten Halsmanschetten beringt, die sich im Feld mit Ferngläsern oder Fernrohren ablesen lassen. Insgesamt wurtden 25.000 Beobachtungen registriert. Die vorliegende Arbeit präsentiert als erste Auswertung dieses Langzeitprojektes 17 Kapiteln, die unterschiedliche Aspekte des winterlichen Gänsezuges beleuchten. Auf drei geografischen Ebenen wird das Zuggeschehen untersucht: zunächst auf der kontinentalen Ebene (Zug von den Brut- in die Wintergebiete), dem überregionalen Niveau (Vernetzung europäischer Rastgebiete) und dem regionalen Niveau (Auswertungen der Rastbestände und Zugbewegungen in Ostfriesland, dem Niederrheingebiet und dem Lauwersmeer) z.T. mit Nutzung der Rasterkartierung und der Telemetriemethode. Zwei Kapitel behandeln soziale Hintergründe des winterlichen Rastgeschehens bei Wildgänsen. Die Dauer des Familienzusammenhaltes stellt einen wesentlichen Punkt für die Frage des Erlernens von Ortstraditionen dar. Der biologische Wert von Ortstreue konnte anhand des Rastverhaltens markierter Gänse am Dollart untersucht werden. Wildgänse nutzen ihre Winterquartiere mit sehr individueller Tradition und nach einer individuellen Art und Weise. Sie besitzen eine "innere Karte" mit ihnen vertrauten Rastgebieten, die sich in einer festen Abfolge oder nach einer bestimmten Strategie nutzen. Die ersten Ergebnisse des Farbmarkierungsprojektes geben Hinweise auf die Entstehung und Funktionsweise dieser "inneren Karte" als Grundlage für die individuelle Rasttradition und ihre soziale Begründung (Fitness-Optimierung). Diese Dissertation vereint Manuskripte und Veröffentlichungen und diskutiert sie vor diesem Hintergrund.

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