Theses and Dissertations at Montana State University (MSU)
Permanent URI for this collectionhttps://scholarworks.montana.edu/handle/1/733
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Item Population structure, gene flow, and genetic diversity of Rocky Mountain bighorn sheep informed by genomic analysis(Montana State University - Bozeman, College of Agriculture, 2020) Flesch, Elizabeth Pearl; Chairperson, Graduate Committee: Jennifer Thomson; Jay J. Rotella, Jennifer M. Thomson, Tabitha A. Graves and Robert A. Garrott were co-authors of the article, 'Evaluating sample size to estimate genetic management metrics in the genomics era' in the journal 'Molecular ecology resources ' which is contained within this dissertation.; Tabitha A. Graves, Jennifer M. Thomson, Kelly M. Proffitt, P.J. White, Thomas R. Stephenson and Robert A. Garrott were co-authors of the article, 'Evaluating wildlife translocations using genomics: a bighorn sheep case study' in the journal 'Ecology and evolution' which is contained within this dissertation.; Tabitha A. Graves, Jennifer M. Thomson, Kelly M. Proffitt and Robert A. Garrott were co-authors of the article, 'Genetic diversity of bighorn sheep population is associated with dispersal, augmentation, and bottlenecks' submitted to the journal 'Biological conservation' which is contained within this dissertation.This dissertation evaluated the genomics of bighorn sheep (Ovis canadensis) herds across the Rocky Mountain West to determine optimal sample size for estimating kinship within and between populations (Chapter Two), to detect gene flow due to natural dispersal and translocations (Chapter Three), and to evaluate the correlation between genetic diversity and influences on population size (Chapter Four). To date, wildlife managers have moved many bighorn sheep across the Rocky Mountain West in an effort to provide new genetic diversity to isolated herds. However, little is known about the genetics of these herds and the real impacts of translocations. To learn how populations have been impacted by these management actions, we genotyped 511 bighorn sheep from multiple populations using a new cutting-edge genomic research technique, the Illumina Ovine High Density array, which contained about 24,000 to 30,000 single nucleotide polymorphisms informative for Rocky Mountain bighorn sheep. First, we determined that a sample size of 20 to 25 bighorn sheep was adequate for assessment of intra- and interpopulation kinship. In addition, we concluded that a universal sample size rule for all wild populations or genetic marker types may not be able to sufficiently address the complexities that impact genomic kinship estimates. Secondly, we synthesized genomic evidence across multiple analyses to evaluate 24 different translocation events; we detected eight successful reintroductions and five successful augmentations. One native population founded most of the examined reintroduced herds, suggesting that environmental conditions did not need to match for populations to persist following reintroduction. Finally, we determined that influences on population size over time were correlated with genetic diversity. Gene flow variables, including unassisted connectivity and animals contributed in augmentations, were more important predictors than historic minimum population size and origin (i.e. native vs. reintroduced). This hypothesis-based research approach will give wildlife managers additional biological insight to help inform various management options for bighorn sheep restoration and conservation.Item A metabolomics approach for the study of long-term progesterone in domestic sheep and physiological processes in domestic and bighorn sheep(Montana State University - Bozeman, College of Agriculture, 2017) Herrygers, Melissa Rashelle; Chairperson, Graduate Committee: James G. Berardinelli; J. M. Thomson, K. A. Perz, K. B. Herrygers and J. G. Berardinelli were co-authors of the article, 'Effect of long-term progesterone on feed efficiency, body compostition, non-esterified fatty acids, and metabolic hormones in mature Rambouillet ewes' submitted to the journal 'Journal of animal science' which is contained within this thesis.; J. M. Thomson, K. A. Perz, K. B. Herrygers, V. Copie, B. Tripet, and J. G. Berardinelli were co-authors of the article, 'Using nuclear magnetic resonance spectroscopy (NMR) metabolic profiling to study the effect of long-term progesterone on metabolic profiles in Rambouillet ewes' submitted to the journal 'Journal of metabolomics' which is contained within this thesis.; J. White, C. Butler, R.A. Garrott, V. Copie, B. Tripet, and J. G. Berardinelli were co-authors of the article, 'Potential identification of metabolic biomarkers using nuclear magnetic resonance spectroscopy (NMR) metabolic profiling for nutrition status, season, and location of bighorn sheep (Ovis canadensis) in Montana and Wyoming' submitted to the journal 'Journal of metabolomics' which is contained within this thesis.Metabolomics allows for a snapshot of global metabolisms by studying metabolic intermediates and products of cellular metabolism. Experiments 1 and 2's objectives were to evaluate the effects of long-term P4 treatment, independent of the influence of the placenta and fetus, on changes in feed efficiency, BW, body composition, NEFA, metabolic hormones, and metabolites identified through nuclear magnetic resonance (NMR) metabolic profiling in mature Rambouillet ewes. Thirty, multiparous, 5- and 6-yr-old Rambouillet ewes were stratified by age and metabolic BW and assigned randomly to receive long-term P4 administration using controlled intravaginal releasing devices (CIDR) or no P4 (CIDRX; CIDR backbone only). Sera samples and body weights were collected every 14-d, along with CIDR/CIDRX replacement. Sera samples were assayed for metabolic hormones, NEFA, and metabolites. There were no differences in BW, RFI, STDMI, body composition, or temporal patterns of T3, T4, NEFA, or metabolites between CIDR- and CIDRX-treated ewes. Insulin concentrations were greater in CIDR-treated ewes than in CIDRX-treated ewes. Long-term P4 did not affect metabolism or body composition, independent from the presence of a fetus or placenta. Progesterone may increase tissue sensitivity to INS. In Experiment 3, the primary aim was to determine if NMR metabolic profiling has the potential to serve as a management tool for evaluating herds of bighorn (Ovis canadensis) sheep. Bighorn sheep herds were sampled between December of 2014 to March of 2015 in Montana and Wyoming. The sampling included 240 bighorn sheep ewes from 13 herds from geographically distinct locations at different times of the year. Metabolites identified by NMR in bighorn sheep serum were analyzed by pathway enrichment analyses, PLS-DAs, and biomarker analyses to determine if bighorn sheep herds can be distinguished by pregnancy status, geographic location, or time of year. NMR metabolic profiling could not distinguish between pregnant and non-pregnant bighorn sheep. Metabolic profiling did differentiate bighorn sheep herds and identified a subset of potential biomarkers that discriminated distinct geographic locations and time of year. Thus, NMR metabolic profiling has the potential to develop a suite of metabolites that wildlife managers can use to assess bighorn sheep nutrition and overall health.Item Seasonal locations of bighorn sheep, mountain goats, and elk on the Haystack Domestic Sheep Allotment, Montana(Montana State University - Bozeman, College of Agriculture, 1993) Byelich, Boyd RaldonItem Habitat comparisons of historically stable and less stable Bighorn sheep populations(Montana State University - Bozeman, College of Agriculture, 2008) Beyer, Ashley Chantel; Chairperson, Graduate Committee: Jeffrey C. Mosley.Limited research has examined how habitat differences between stable and less stable bighorn populations may influence their success. Understanding these habitat differences may help explain how habitat contributes to bighorn sheep population stability. The objective of the study was to identify potential limiting habitat factors for the Tendoy Mountains bighorn sheep (Ovis canadensis) population in western Montana. Habitat variables that were evaluated are unlikely to be influenced by fine-scale weather or disturbance patterns. Land cover, slope, aspect, elevation, landscape ruggedness, solar radiation index (SRI), and distance to escape terrain were measured using GIS. Shrub canopy cover, graminoid and forb frequency, and horizontal visibility were measured in the field. Logistic regression was used to identify habitat differences between the stable and less stable sheep populations in summer and winter. Odds ratios from the logistic regressions were used to identify potential limiting habitat variables for the less stable population. Results from this study indicate that landscape ruggedness (P <0.01) and aspect (P <0.01) in summer ranges, and landscape ruggedness (P =0.01), aspect (P <0.01), and SRI (P <0.01) in winter ranges were the habitat characteristics most likely influencing population stability. Landscape ruggedness and SRI are relatively new habitat metrics that require more research to determine threshold values for bighorn sheep habitat. Results from this study provide initial insights into potential threshold values for landscape ruggedness and SRI for Rocky Mountain bighorns.