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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

Endogenous and exogenous control of ovarian dynamics in wapiti

McCorkell, Robert Bruce 24 July 2006
A series of studies were guided by the principal hypothesis that it was necessary to characterize ovarian function during the seasons of the annual reproductive cycle in wapiti and that from this knowledge novel methods of exogenous control of ovarian function would be possible. To augment existing knowledge about endogenous control of ovarian function in wapiti studies were conducted to characterize ovarian follicle dynamics during the estrous season and to characterize ovarian follicular dynamics during the periods of transition into and out of the breeding season. The third study was designed to characterize ovarian follicle development and ovulation synchrony subsequent to an estrous synchronization protocol used commercially. To evaluate novel methods of exogenous control of ovarian function studies were conducted to determine if follicular wave emergence could be electively induced using hormonal or surgical treatments to evaluate novel ovarian superstimulatory treatment protocols. <p>It was concluded from the studies of ovarian function that follicle development during the breeding season was characterized by the regular and synchronous development of follicular waves and that 2, 3, or 4 waves occurred during each interovulatory interval. Transition into the breeding season was preceded by one short interovulatory interval (9 days) characterized by one wave of follicle development and a small, short-lived and hypo-functional corpus luteum. The last estrous cycle of the breeding season was similar to estrous cycles during the rut (21 days), but and transition to anestrus was marked by a failure of the dominant follicle to ovulate after luteal regression. The treatment protocol used commercially for estrous synchronization was effective, but unnecessarily long. It was concluded from the studies on exogenous control of ovarian function that follicular wave emergence could be electively induced using steroid hormones or follicle ablation and may be useful for estrus synchronization and superstimulatory protocols. The tested superstimulatory treatments were effective and had the advantage of reducing the treatment period by 6 days and the number of times the animals are handled by one third over a more conventional method. However, oocyte and embryo quality were not evaluated. <p>As a result of the studies conducted and one previous study during the anouvlatory season follicle and luteal dynamics are now known in wapiti for all seasons of the year and this knowledge will provide a template upon which other species of deer can be compared. The final two studies support the principal hypothesis. The novel methods of exogenous ovarian control tested increase the potential for success when applying reproductive technologies and the successful application of these methods in wapiti should lead to their successful use in other species of deer.
2

Cloning and expression of the elk (<i>Cervus elaphus</i>) pituitary glycoprotein hormones

Okrainetz, Rena June 17 December 2004
The North American elk or wapiti is an indigenous species to Canada. Understanding of the reproductive physiology of elk is limited, as little research has been conducted in this field as compared to domestic farmed species. In order to make available the tools to study reproductive physiology of the elk this thesis describes the cloning and expression of elk pituitary glycoprotein hormone cDNAs. The common gonadotropin a-subunit, and FSH, LH and TSH b-subunit elk cDNAs were amplified by reverse transcription and polymerase chain reaction (RT-PCR). There was a high degree of nucleotide similarity between the elk a and b subunits when compared with reported sequences from other species. The cDNAs for the pituitary glycoprotein hormone genes were used as probes to investigate seasonal expression in the female elk pituitary gland. Steady state levels of the common a-subunit mRNA was observed regardless of the reproductive season, but a significant increase in expression occurred during the breeding season. The FSH and LH b-subunit genes were expressed at low levels in pituitary glands of animals during presumed anestrous and pregnancy, but levels considerably increased during estrus. In contrast, levels of TSH b-subunit mRNA were similar regardless of the reproductive status. The FSH cDNAs were also transfected into a Chinese hamster ovary (CHO) mammalian expression system, aimed at the production of recombinant elk FSH. Transfected CHO cell lines were screened for expression of a- and FSH b-subunit mRNA by Northern blot. Activity of FSH was equivalent to ~100 mIU/ml of recombinant human FSH (Gonal-FTM), identified by FSH receptor signaling in an in vitro cell based assay. In conclusion, this work represents an advance towards understanding the molecular basis of seasonal reproduction in elk. This information and the availability of elk recombinant FSH will be useful for the application of advanced reproductive technologies required for the rapid expansion of healthy, disease resistant, and genetically superior animals, which are important for domestic production and wildlife management.
3

Cloning and expression of the elk (<i>Cervus elaphus</i>) pituitary glycoprotein hormones

Okrainetz, Rena June 17 December 2004 (has links)
The North American elk or wapiti is an indigenous species to Canada. Understanding of the reproductive physiology of elk is limited, as little research has been conducted in this field as compared to domestic farmed species. In order to make available the tools to study reproductive physiology of the elk this thesis describes the cloning and expression of elk pituitary glycoprotein hormone cDNAs. The common gonadotropin a-subunit, and FSH, LH and TSH b-subunit elk cDNAs were amplified by reverse transcription and polymerase chain reaction (RT-PCR). There was a high degree of nucleotide similarity between the elk a and b subunits when compared with reported sequences from other species. The cDNAs for the pituitary glycoprotein hormone genes were used as probes to investigate seasonal expression in the female elk pituitary gland. Steady state levels of the common a-subunit mRNA was observed regardless of the reproductive season, but a significant increase in expression occurred during the breeding season. The FSH and LH b-subunit genes were expressed at low levels in pituitary glands of animals during presumed anestrous and pregnancy, but levels considerably increased during estrus. In contrast, levels of TSH b-subunit mRNA were similar regardless of the reproductive status. The FSH cDNAs were also transfected into a Chinese hamster ovary (CHO) mammalian expression system, aimed at the production of recombinant elk FSH. Transfected CHO cell lines were screened for expression of a- and FSH b-subunit mRNA by Northern blot. Activity of FSH was equivalent to ~100 mIU/ml of recombinant human FSH (Gonal-FTM), identified by FSH receptor signaling in an in vitro cell based assay. In conclusion, this work represents an advance towards understanding the molecular basis of seasonal reproduction in elk. This information and the availability of elk recombinant FSH will be useful for the application of advanced reproductive technologies required for the rapid expansion of healthy, disease resistant, and genetically superior animals, which are important for domestic production and wildlife management.
4

Endogenous and exogenous control of ovarian dynamics in wapiti

McCorkell, Robert Bruce 24 July 2006 (has links)
A series of studies were guided by the principal hypothesis that it was necessary to characterize ovarian function during the seasons of the annual reproductive cycle in wapiti and that from this knowledge novel methods of exogenous control of ovarian function would be possible. To augment existing knowledge about endogenous control of ovarian function in wapiti studies were conducted to characterize ovarian follicle dynamics during the estrous season and to characterize ovarian follicular dynamics during the periods of transition into and out of the breeding season. The third study was designed to characterize ovarian follicle development and ovulation synchrony subsequent to an estrous synchronization protocol used commercially. To evaluate novel methods of exogenous control of ovarian function studies were conducted to determine if follicular wave emergence could be electively induced using hormonal or surgical treatments to evaluate novel ovarian superstimulatory treatment protocols. <p>It was concluded from the studies of ovarian function that follicle development during the breeding season was characterized by the regular and synchronous development of follicular waves and that 2, 3, or 4 waves occurred during each interovulatory interval. Transition into the breeding season was preceded by one short interovulatory interval (9 days) characterized by one wave of follicle development and a small, short-lived and hypo-functional corpus luteum. The last estrous cycle of the breeding season was similar to estrous cycles during the rut (21 days), but and transition to anestrus was marked by a failure of the dominant follicle to ovulate after luteal regression. The treatment protocol used commercially for estrous synchronization was effective, but unnecessarily long. It was concluded from the studies on exogenous control of ovarian function that follicular wave emergence could be electively induced using steroid hormones or follicle ablation and may be useful for estrus synchronization and superstimulatory protocols. The tested superstimulatory treatments were effective and had the advantage of reducing the treatment period by 6 days and the number of times the animals are handled by one third over a more conventional method. However, oocyte and embryo quality were not evaluated. <p>As a result of the studies conducted and one previous study during the anouvlatory season follicle and luteal dynamics are now known in wapiti for all seasons of the year and this knowledge will provide a template upon which other species of deer can be compared. The final two studies support the principal hypothesis. The novel methods of exogenous ovarian control tested increase the potential for success when applying reproductive technologies and the successful application of these methods in wapiti should lead to their successful use in other species of deer.
5

Genetic Assessment of Native and Non-Native White-Tailed Deer (Odocoileus Virginianus) in the Southcentral U.S.

Youngmann, Jordan L 14 December 2018 (has links)
Population genetics of white-tailed deer (Odocoileus virginianus) have been influenced through human actions including the translocation of deer from across the United States in the 1900s and, recently, the creation of the captive-cervid industry, which uses animal husbandry to manipulate genetic variation. To assess the effects of these actions, I studied the genetic variation of free-range and captive populations of deer across the southcentral U.S. using a 14 microsatellite panel. In free-range populations I found genetic structure that divided deer west to east along the Mississippi River. Additionally, I found that captive populations were genetically distinct from geographically proximate free-range populations. However, after 2 generations of hybridization, this distinction disappeared. Finally, using both Bayesian clustering and multivariate approaches, I was able to identify a non-native individual from local free-range populations in southern Mississippi. Using these methods, wildlife managers can further investigate cases of hybridization between non-native deer and free-range populations.
6

Evaluating potential growth strategies using bone histology in Pleistocene-Holocene <i>Odocoileus virginianus</i> (Mammalia) from Florida.

Gerwitz, Andrew 08 August 2016 (has links)
No description available.
7

Caractérisation techno-économique d'industries en bois de cervidés du Badegoulien et du Magdalénien : le cas du Rond-du-Barry (Haute-Loire) et de Rochereil (Dordogne) / Non communiqué

Rémy, Delphine 02 December 2013 (has links)
L’analyse technologique des industries osseuses paléolithiques est une discipline encorerelativement jeune. Nous avons appliqué cette méthode d’analyse à deux assemblages : celuide la grotte du Rond-du-Barry (Haute-Loire) qui a livré une longue séquence allant duBadegoulien ancien au Magdalénien supérieur ; et celui de la grotte de Rochereil (Dordogne)qui a livré un ensemble attribué au Magdalénien supérieur.Dans une perspective synchronique, l’analyse technologique a permis de défi nir les modalitésd’exploitation des bois de cervidés dans ces gisements pour chaque période envisagée duBadegoulien ancien jusqu’au Magdalénien supérieur, pour les replacer dans le contexte généralde ces groupes chrono-culturels tels qu’ils sont connus à l’heure actuelle.Dans une perspective diachronique, nous analysons dans leur aspect technologique leschangements qui sont intervenus dans le travail des bois de cervidés entre le Badegoulien etle Magdalénien, changements qui se caractérisent avant tout par l’abandon du débitage parpercussion directe et le retour au débitage par double rainurage. Enfi n nous discutons du rôleet du statut qu’ont pu détenir ces deux gisements dans leur contexte local et régional. / Technological analysis of paleolithic bone industries is a still relatively young discipline. Weapplied this method to the material from two sites: the Rond-du-Barry (Haute-Loire) whichdelivered a long sequence from ancient Badegoulian to upper Magdalenian ; and Rochereil(Dordogne) which delivered an assemblage attributed to upper Magdalenian.In a synchronic perspective, the technological analysis allowed to defi ne the modalitiesof exploitation of antler in these sites for every period, from ancient Badegoulien to upperMagdalenian, and then to replace them in the general context of these chrono-cultural groupssuch as they are known at the moment.In a diachronic perspective, we analyze, in their technological aspect, the changes thatoccurred in antlerworking between the Badegoulian and the Magdalenian, which are aboveall characterized by the abandonment of the debitage by direct percussion and the groove andsplinter technique. Finally we discuss the role and the status of these two sites in their localand regional context.
8

Écologie alimentaire et paléoenvironnements des cervidés européens du Pléistocène inférieur : le message des textures de micro-usure dentaire / Feeding ecology and paleoenvironments of ancient cervids from the early Pleistocene of Europe : the message of the dental microwear textures

Berlioz, Emilie 05 December 2017 (has links)
Le refroidissement global et les oscillations entre cycles glaciaires et interglaciaires du Pléistocène inférieur ont pour conséquence une alternance entre milieux steppiques et forestiers, favorisant par là-même renouvellements et dispersions fauniques dont celui du genre Homo.Dans les interprétations paléoenvironnementales basées sur les assemblages fauniques, les cervidés, parmi les plus abondants mammifères, sont classiquement considérés comme forestiers, mais ce paradigme ne reflète pas la complexité de la diversité écologique réelle des cervidés.L'analyse texturale de 921 spécimens représentant les 5 cervidés actuels à l'écologie référencée a permis d'établir une robuste base de données et d'attester du lien significatif entre micro-usure dentaire et ressources végétales. L'analyse de 547 cervidés fossiles issus de 15 localités européennes souligne leur grande diversité écologique. Eucladoceros ctenoides et Metacervoceros rhenanus présentent une alimentation plastique. Leur analyse permet l'identification de réponses alimentaires adaptatives aux modifications environnementales liées aux oscillations climatiques. Ces deux cervidés, eurytopiques, constituent des indicateurs écologiques incontournables. La composante forestière supportée par la présence des cervidés est ici remise en cause ; les cervidés étant plus diversifiés écologiquement. L'analyse de la texture de la micro-usure dentaire des cervidés présents dans des sites européens, où la présence du genre Homo a été avancée, vise à identifier le type potentiel d'habitat favorable à sa dispersion en Eurasie. / The early Pleistocene is a period of global cooling and climatic oscillations punctuated by glacial and interglacial cycles. This period of climatic instability leads to an alternation of steppe and forest habitats resulting in faunal renewals and dispersals, including Homo dispersal.In paleoenvironmental reconstructions based on faunal assemblages, deer, which are among the most abundant mammals, are traditionally considered forest dwellers. However, this paradigm is far from reflecting the real complexity of deer ecological diversity.Via the textural analysis of 921 representatives of the 5 extant European deer with known ecology, a solid reference database has been setup. It attests of the significative link existing between dental micro-wear and vegetal resources. The analysis of 547 fossils from 15 European localities underlines the ecological diversity among fossil deer. Eucladoceros ctenoides and Metacervoceros rhenanus are plastic in their diet. The analysis of such deer allows the identification of dietary adaptive answers to environmental modifications resulting from climatic oscillations. Being eurytopic, they constitute essential proxies for paleoenvironmental reconstructions. The results challenge the link existing between the occurrence of deer and the presence of forest habitats, as deer are ecologically more diversified.The textural analysis of deer from European human bearing localities aims at characterizing potential habitats favorable toward Homo dispersion in Eurasia.

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