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Cloning and expression of the elk (<i>Cervus elaphus</i>) pituitary glycoprotein hormonesOkrainetz, 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.
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Elk/cattle interactions : an annotated bibliography for the Internet /Garcia, Roberto M. January 2002 (has links)
Thesis (M.S.)--University of Idaho, 2002. / Includes bibliographical references. The annotated bibliography portion is also available via the World Wide Web.
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Structural study of the southwest part of Elk Basin Anticline, Bighorn Basin, WyomingHuson, Sarah Ann January 2002 (has links)
A subsurface and surface structural study was completed in the southwest part of the Elk Basin Anticline, Wyoming. The goals of this study were to better improve preexisting geologic surface maps of the area and to better understand subsurface structural relationships. A normal fault with a splay to the north was recorded through sections 25, 26. and 35 of T58N, RI00W. Using well logs to create across section, this fault was traced in the subsurface. Strike and dip measurements in undisturbed areas of the anticline averaged 332° (azimuth) or N28W (quadrant). In an area of anomalous strike (section 26 of T58N, R1 00W), strike readings averaged 303° (azimuth) or N57W (quadrant). This region has been interpreted as an area rotated counter clockwise due to drag on a subsurface tear fault located at the northern end of the anticline. The current study is significant since it lends support to a little studied Laramide structural feature. / Department of Geology
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Gradients of predation risk affect distribution and migration of a large herbivoreGrigg, Jamin Lyle. January 2007 (has links) (PDF)
Thesis (M.S.)--Montana State University--Bozeman, 2007. / Typescript. Chairperson, Graduate Committee: Robert A. Garrott. Includes bibliographical references (leaves 57-63).
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Prey use by male and female cougars in an elk and mule deer communityWhite, Kevin Robert. January 2009 (has links) (PDF)
Thesis (M.S. in natural resource sciences)--Washington State University, May 2009. / Title from PDF title page (viewed on May 21, 2009). "Department of Natural Resource Sciences." Includes bibliographical references (p. 19-24).
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Validation of diagnostic assays and development of molecular epidemiological tools for brucellosisFluegel, Amanda M. January 2008 (has links)
Thesis (M.S.)--University of Wyoming, 2008. / Title from PDF title page (viewed on August 4, 2009). Includes bibliographical references.
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Some epizootiological studies of bluetongue in wild ruminantsMurray, James Oliver, January 1970 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1970. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
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Evaluation of the soil land inference model in Big Elk Creek Watershed, Chester County, PennsylvaniaVaraghur, Ranjani. Day, Rick L., January 2008 (has links)
Thesis (M.S.)--Pennsylvania State University, 2008. / Mode of access: World Wide Web. Thesis advisor: Rick Lane Day.
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Analysis of mountain lion predation upon mule deer and elk in the Idaho Primitive areaHornocker, Maurice Gail January 1967 (has links)
This study was designed (1) to investigate the dynamics of a mountain lion population, and (2) to assess the impact of a population of lions on populations of big-game animals. The research was carried on in the Idaho Primitive area; intensive work was limited to the winter and early spring seasons.
Lion population numbers were stable during the three-year study period, and available evidence indicates the present population
level existed for some time prior to the start of the study-Intraspecific relationships, manifested through territoriality, acted to limit lion numbers and maintain population stability. Dispersal and mortality, particularly of young individuals, appeared to be important limiting mechanisms.
The population was centered around a nucleus of mature individuals well-established on territories, but segments of the population were dynamic, exhibiting an inflow and outflow of individuals from season to season. These transients were composed predominantly of young animals.
Strife appeared to be kept to a minimum by a "mutual avoidance" behavorial mechanism. Specific hunting territories were shared but appeared never to be used by more than one lion or family of lions at a time. Individuals, regardless of sex, appeared to respect the presence of another in a specific area. The "mutual avoidance" hypothesis is advanced as an important factor in the maintenance of lion populations. This mechanism provides for the distribution of lions in both space and time without costly-fighting. It also appears to insure greater success in securing large prey animals.
Population size of prey species -- mule deer, elk, and bighorn
sheep -- was established by making ground and aerial counts each year. Bighorn sheep numbers remained constant during the three-year period, but populations of deer and elk, the principal prey species, increased. The range was considered overstocked by deer and elk.
Forty-four elk and 39 deer were recorded as definitely killed by lions during the three-year period. Only two kills of bighorn sheep were found; lion predation on this species appeared insignificant.
Seventy-five percent of the elk killed by lions were 1% years old or less and 9% years or older; 57 percent of the deer kills were in these age classes. More "young" than "old" animals were killed. Lions were non-selective in their killing, except for "negative selectivity" in the case of mature bull elk. Factors acting separately or collectively to increase prey vulnerability included prey density, behavior, age, health, inter - and perhaps intraspecific strife, and the lion's predatory characteristics.
It was concluded that elk and deer populations were limited by the winter food supply and that predation by lions was inconsequential
in determining ultimate numbers of elk and deer. Lion predation, however, is a powerful force acting to dampen and protract severe prey oscillations and to distribute ungulates on restricted, critical range. From the theoretical standpoint, it also appears to be a strong evolutionary force, acting to remove less fit individuals from the population. The effects and influence of such predation are considered of great significance in the maintenance of ecologic stability in wilderness environments. / Science, Faculty of / Zoology, Department of / Graduate
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A Management Study of the Cache Elk HerdHancock, Norman V. 01 May 1955 (has links)
American elk, by virtue of their distribution, were the most cosmopolitan members of the cervid family at the time of white settlement of North America. At this early date elk were present in every major region of what is now continental United States, as well as in northern Mexico. they likewise were abundant in upper and lower Canada, though records do Lot corroborate their presence too far north on the Atlantic coast. Although generally existent throughout the western states, elk were sparsely distributed in Nevada, southern Utah, and most of Arizona and New Mexico. Paucity of elk was also noted in eastern portions of Washington and Oregon.
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