Life Sciences Commons^™

The Economic Role Of Range Livestock Production In Kasungu Agricultural Development Division (Kadd), Malawi, Phillip H. W. Phiri

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study was conducted to determine the effects of season and auction and produce marketing systems on prices received by farmers for livestock sales and the effect of price on cattle numbers sold in KADD. Livestock population, carrying capacity, and stocking rate were estimated. Data were analyzed using pie charts, regression methods, and analysis of variance.

There was no significant difference (P=.06) between cattle prices per kilogram during the wet season and after harvest. During the wet season, significantly more cattle were sold than after harvest (P< .001) to purchase food and farm inputs, and pay school fees and medical bills. Market price was only a secondary factor.

Carrying capacity and stocking rate were estimated at 15.00 kg …

Delineation Of Ecological Units For The Ashley National Forest, At The Landscape Level, Using Classification Tree Modeling, Teresa H. Swiatek

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study integrated remotely sensed data, geographic information system (GIS), and classification tree-based modeling to delineate ecological units for the Ashley National Forest. Data points, provided by the Ashley National Forest, with a known location and dominant vegetation type, were related to data layers that were determined to be helpful in a landtype classification. These layers included elevation, slope, aspect, potential solar irradiation, precipitation, geology, basins, Landsat thematic mapper (TM) bands 3, 4, 5, and 6, and basic land cover. These points, with their related information, were then used to train the tree-based model for landtype classification. This resulted in …

Interaction Of The Human Serine Protease Inhibitor Alpha-1-Antitrypsin With Cryptosporidium Parvum, John Russell Forney

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The human serine protease inhibitor (serpin) alpha-1-antitrypsin (AAT) was studied for potential interaction with components of the protozoan parasite Cryptosporidium parvum. A homogenate prepared from C. parvum oocysts was incubated with purified human AAT, and complexes formed between the serpin and components of the homogenate were detected using an enzyme-linked immunosorbent assay (ELISA). Serpin:parasite infections were effectively blocked by preincubating AAT with a cognate target enzyme, porcine pancreatic elastase, prior to performing the ELISA on the homogenate. Incubation of a mixture of C. parvum oocysts and sporozoites with AAT demonstrated preferential fluorescence labeling of the sporozoite surface membrane by indirect …

Wetland Delineation Of Camp Ripley In Minnesota, Richard A. Spencer

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Department of Defense (DoD) maintains approximately 25 million acres of land that is used for military training in the continental United States. Currently, federal and state laws and regulations require that the DoD land be managed so that any activity, including training, will have a minimal effect on the natural environment.

Effectiveness Of Grid Systems For Pheromone-Trapping Sparse Gypsy Moth Populations In Mountainous Terrain In The Intermountain West, Colleen Keyes

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Two field experiments determined an effective intertrap distance (ITD) for early detection and delimitation sparse gypsy moth (Lepidoptera: Lymantriidae, Lymantria dispar L.) populations in mountainous terrain. This study found that current Animal and Plant Health Inspection Service trapping guidelines are not sufficient for early detection of small gypsy moth populations in mountainous terrain. Detection trapping in mountainous terrain should have an ITD of not more than 804 m. Delimiting trapping should use a grid design with an ITD of 152 m.

A related study determined natural adult male mortality in the climate of the intermountain West, which includes Utah, Nevada, …

Bark Beetle Activity In Douglas-Fir, Pseudotsuga Menziesii Var. Glauca Mirb. (Franco), Following The 1994 Beaver Mountain Fire, Catherine A. Cunningham

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The 1994 Beaver Mountain fire ignited the canopies of subalpine fir, Abies lasiocarpa, and spread ground fire into adjacent Douglas-fir forests, Pseudotsuga menziesii var. glauca. Despite shorter flight seasons due to lower annual temperatures and persistent snow, the Douglas-fir bark beetle, Dendroctonus pseudotsugae Hopkins, attacked a range of moderately fire-injured host conifers. Logistic regression models illustrated that in 1995 associated bark beetles selected large diameter Douglas-fir with 60-80% bole char, 60-80% crown volume scorch, and 50-70% probability of mortality due to fire. In 1996 beetle preference shifted to smaller diameter trees with lighter fire injury. Tree size was …

Evolutionary Genetics Of Canyon Treefrogs (Hyla Arenicolor), Roy A. Murray

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Population genetics is the study of the mechanisms that cause genetic change in populations over time. Genetic changes may lead to both adaptive evolution and speciation. While the former process is fairly well understood, many questions remain unanswered with regard to the process of speciation. How important is population isolation in the process of speciation? How long must populations be isolated before speciation is complete? Are the genetic changes that take place during speciation caused mainly by natural selection or does genetic drift play a substantial role? Can genetic drift alone lead to reproductive isolation? These types of questions have …

Ecological Amplitude And Invasion Of Diffuse Knapweed At Yakima Training Center, Washington, Donna Denise Wilcox

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Diffuse knapweed (Centaurea diffusa) is an introduced annual or short-lived perennial from Eurasia that has become a threat to native rangelands in the Pacific Northwest. Military training activities on the Yakima Training Center (YTC) increase the likelihood that knapweed will expand its range at YTC. This study, conducted in a major watershed at YTC, focused on: 1) how a variety of environmental variables influences knapweed distribution, 2) the use of Landsat Thematic Mapper (TM) imagery to map existing knapweed populations, and 3) the use of a logistic regression model and geographical information systems (GIS) to create a potential …

Second Growth Forest As Potential Marten Habitat In Western Newfoundland: An Examination Of Forest Habitat Structure And Microtine Abundance, Brian R. Sturtevant

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The American marten (Martes americana) is associated with large tracts of relatively undisturbed, mature coniferous forests. I examined coarse woody debris (CWD) structure and small mammal abundance with respect to forest age and stem structure within second-growth forests, in comparison with old-growth stands in western Newfoundland. Results suggest that a critical change in marten habitat quality may occur at stand senescence, due to decreased tree competition, more complex subcanopy structure, and increased meadow vole (Microtus pennsylvanicus) abundance.

Analysis of stem structure within a chronosequence of 19 second-growth stands indicated high intertree competition, with dense canopy closure …

A Survey Of Employees Of The United States Department Of Agriculture's Animal Damage Control Program, Susan A. Schroeder

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study examined the attitudes of employees of the United States Department of Agriculture's Animal Damage Control (ADC) Program. This research examined ADC employees' attitudes about wildlife, the ADC program and ADC employment, wildlife damage management methods, euthanasia and the killing process, and the role of various public and private groups on ADC policy. This study also applied the theory of organizational capture to the ADC program to test its utility in explaining the attitudes and behaviors of employees. Results were based on a survey of ADC employees conducted in January 1995.

Survey responses were analyzed to explore associations between …

Quantification Of Landscape Structure Within The Land Condition-Trend Analysis Monitoring Program At Camp Williams, Utah, Lorraine Munguia

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Land Condition-Trend Analysis (LCTA) program was developed by the U.S. Army to assist in the sustainable management of natural resources on U.S. Army lands. The LCTA program applies a standardized procedure in order to select long-term monitoring sites. The LCTA monitoring program was applied to Camp Williams, a National Army Guard training site located in central Utah. Due to the criteria set by the LCTA monitoring program, 61 percent of Camp Williams was explicitly excluded from the LCTA monitoring protocol because it appeared to be more heterogeneous, which would make it difficult to locate monitoring sites in the field. …

Physical Factors Influencing Survival To Emergence And Time Of Emergence Of Shoreslope-Spawned Kokanee Salmon In Flaming Gorge Reservoir, Utah-Wyoming, Randall J. Jeric

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I used incubation baskets containing viable eggs and spawning substrate to estimate the survival to emergence and time of emergence of kokanee salmon Oncorhynchus nerka at depths to 20 m in Flaming Gorge Reservoir, Utah-Wyoming. Traps on the incubation baskets captured fry emerging from a known quantity of eggs. Water drawn into a syringe from an intragravel pipe buried near each incubation basket was used to determine intragravel dissolved oxygen concentrations throughout the intragravel period. Water from control baskets without eggs did not have significantly greater dissolved oxygen concentrations than adjacent water. A jar associated with each incubation basket collected …

Acceptability And Proximate Composition Of Meat-Vegetable Sticks Versus All-Meat Sticks Adjusted To Ph 4.6 Or 5.2 With Citric Or Lactic Acids, Ronnald Dean Quinton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A new innovative product, stewsticks, made with beef, pork, spices, and dehydrated vegetables, was developed as a nutritious snack. Lactic or citric acid was added at pH 5.2 or 4.6 to both meatsticks and stewsticks. Meatsticks and stewsticks were prepared by mixing ingredients until a cohesive mass was obtained. This mixture was then extruded into sticks that were cooked to about 50% of original weight. Sticks were then cut to desired length, packaged, and stored. Then meatsticks (beef, pork, and spices) were compared to stewsticks for appearance, texture, flavor, and overall acceptability.

The stewsticks had excellent shelf life due to …

Survival Of Microorganisms On Meat Surfaces Treated With Ultra-High Temperatures, Bret Max Mattinson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Sterile ceramic plates and the surface of beef steaks were inoculated with the pathogenic microorganisms Listeria monocytogenes, Campylobacter jejuni, Escherichia coli and Salmonella typhimurium. Samples were also inoculated with nonpathogenic microorganisms Clostridium sporogenes ATCC 7955, Pseudomonas aeruginosa, and Bacillus stearothermophilus. Concentrations of organisms in the pure culture used to inoculate the samples were selected within the range of 10⁶ to 10⁸ colony forming units/ml (CFU/ml). Samples were treated with ultra-high temperature (UHT), and· the surviving organisms were recovered and counted. Meat samples were exposed to 1100°C for 22 seconds.

Beef steaks inoculated with pathogenic microorganisms had …

Manufacture, Shelf Stability, And Acceptability Of Aseptically Packaged, Unripened Soft Cheese Produced By Post-Ultra-High Temperature Acidulant Injection Of Ultrafiltered Milk Concentrate, Elena S. Moiseeva

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study investigated the manufacturing procedures and texture attributes of direct acid set of an unripened, shelf-stable cheese variety produced by the combined technologies of ultrafiltration and ultra-high temperature processing. Product evaluation included physical and chemical properties such as gel strength, syneresis, pH, moisture, protein, and fat. Whole milk was concentrated by ultrafiltration to 30, 35, and 40% total solids. Milk retentate was ultra-high temperature-processed by preheating to 65 or 77°C, sterilized at 141°C for 4 s by direct steam injection, flash cooled to approximately 62 or 72°C, homogenized in two stages at either 13.8/2.1 or 27.6/4.1 MPa, cooled to …

Fats And Iron In The Rat Colon: Effects On Lipid Peroxidation, Ji Jenny Chin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Preliminary studies were undertaken to investigate whether or not added iron (0, 35, 880 ppm of iron as ferrous fumarate) and fat type (corn oil, beef tallow, or menhaden oil) influenced the oxidation of the rat diet during storage. Iron level affected thiobarbituric acid (TBA) values only in the menhaden oil diets. Storage for 4 d did not affect TBA values of the diets. Neither food intake nor body weight of the rats was affected by the different diets, suggesting all diets were equally acceptable to rats.

The effects of iron supplementation and fat type on in vivo lipid peroxidation …

Microbiological And Sensory Effects Of Milk Processed For Extended Shelf Life And The Development Of Rapid Methods To Quantitate Spores And Lipase Activity, Michael R. Blake

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The initial aim of this work was to evaluate processing conditions for extended shelf life (ESL) milk to have a shelf life at refrigeration temperature of 60 d. Milk was processed on a pilot-scale ultra-high-temperature processing plant and evaluated for microbial and sensory quality over 60 d at 7°C storage. Results of this study showed that lower process temperatures were preferable to minimize cooked flavors and that the minimum safe processing temperature was 134°C for 4 s as determined by the destruction of bacterial spores in the processed milk.

Consumer preference panel results indicated that consumers preferred milk processed at …

Competitive Interactions Between A Native And Exotic Trout Species In High Mountain Streams, Heather M. Thomas

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Populations of the introduced book trout, Salvelinus fontinalis, have recently become more widespread and abundant in western North American streams, possible at the expense of native Colorado River cutthroat trout, Oncorhynchus clarki pleuriticus. We examined the intensity and potential mechanism of competition between these species.

Feeding experiments in laboratory stream channels showed that cutthroat trout feeding efficiency decreases in the presence of a brook trout. Decreased feeding efficiency appeared to be due to interference, as cutthroat trout were inactive in the presence of the brook trout. Evidence for interference competition in the feeding experiments was also given by the …

The Effects Of Osmotic Potential On Ammonification, Immobilization, Nitrous Oxide Production, And Nitrification Rates In Penoyer Soil, Andrew P. Low

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

An isotopic dilution method was used to test the effects of osmotic potential, (𝛹_s), upon nitrification, ammonification, N-immobilization, and nitrous oxide production rates in soil at solute concentrations encountered in Penoyer soil. A nitrification potential assay was also performed to approximate maximum nitrification rates.

Nitrification potential rates in soil slurries exponentially declined in response to decreased osmotic potential. However, nitrification was independent of salt concentration at the ambient NH₄⁺ concentrations of the soil. The differential response was attributed to the variable NH_4⁺ substrate quantities. The effects of osmotic potential were secondary to NH_{4 …}

Alteration In Basic Macrophage And Lymphocyte Cytokines From Benzene And Phenol In The Drinking Water Of Male Institute Of Cancer Research Mice, Jay C. Albretsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Groundwater contamination is a concern due to the large number of people that can become exposed to the contaminant. The chemicals benzene and phenol are known groundwater contaminants. The main health problem caused by benzene or phenol is bone marrow toxicity. Benzene and phenol are also immunotoxins reported to cause decreased thymic weights, altered lymphocyte mitogenic responses, and lower antibody production.

Cytokines are key signaling molecules produced by the cells of the immune system to activate other cells in the immune system, produce antibodies, and recruit other cells to sites of inflammation. The purpose of this study was to determine …

Development Of An Ovine Genome Map With Emphasis On In Situ Hybridization, Melanie R. Heaton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Livestock genome maps are used to identify economic trait loci and loci proximal to genes affecting economically important traits. This research contributes to the development of the ovine genome map by establishing techniques to physically map large DNA inserts to ovine chromosomes using fluorescent in situ hybridization. Fluorescent in situ hybridization techniques were established using yeast artificial chromosomes as DNA probes. Probes were as large as 1,000,000 kilobases and hybridized to fixed ovine metaphase chromosomes from a callipyge ewe. Three yeast artificial chromosome probes contained a genetic marker for the ovine callipyge gene. Probes were assigned to ovine chromosome pair …

An Integration Of Tillage And Herbicides To Control Jointed Goatgrass (Aegilops Cylindrica Host.) In Winter Wheat, Troy M. Price

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

An integrated management approach for jointed goatgrass control was investigated at two farms in northern Utah using three tillage regimes and tree herbicides. The tillage regimes included no tillage, conservation tillage, and conventional tillage. Each regime was composed of different tillage practices common in the Intermountain West. A preemergence herbicide, clomazone, and two postergance herbicides, 2, 4-D and glyphosate, were investigated. Greenhouse studies were also conducted to investigate clomazone efficacy and depth of planting of winter wheat and jointed goatgrass.

Differential sensitivity to clomazone between jointed goatgrass and winter wheat did not occur in the greenhouse for the rates tested. …

Association Of The Major Histocompatibility Complex With Autism, Wayne W. Daniels

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The pathogenesis of autism has proven difficult to characterize. However, in many recent studies, it is suggested that the onset of this disorder is the result of multiple etiological factors, which include genetic, immunologic, and viral elements.

Possible immunological influences found in subpopulations of patients with autism include decreased lymphocyte responsiveness, reduced natural killer cell activity, abnormal response to rubella vaccine, abnormal immune response to brain tissue, and decreased plasma levels of the fourth component of complement(C4). These aberrations and others imply a possible autoimmune mechanism in some cases for the development of autism.

C4 deficiencies have been found in …

Phylogenetic Studies Of The United States Bluetongue Viruses And Characterization Of The Viral Vp4 Protein, I-Jen Huang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Bluetongue virus (BTV) is transmitted by arthropod vectors and causes bluetongue disease with serious economic loss in many regions of the world. The replication mechanism of bluetongue virus is still not clear. To have a better understanding regarding the viral replication, the function of each individual protein has to be identified. This study used molecular biology techniques to investigate the function of the inner core protein VP4.

The M1 genes of United States bluetongue virus serotypes-2, -10, -11, -13, and -17 were cloned and sequenced. The length of each of the five M1 genes is 1981 nucleotides. The coding region …

The Effect Of Salinity Level Upon The Yield, Root Growth, And Water Extraction Of Contrasting Rooting Subpopulations Of Alfalfa (Medicago Sativa) Under Conditions Of Zero Leaching, Laura A. Vincent

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A major problem in irrigated agriculture in the Western U.S. is the gradual accumulation of salinity in the plant root zone. These nonuniformly saline soils contain increasing amounts of salinity with depth, and salt accumulation is accelerated in situations where leaching is minimized. Root growth and thus plant yield is limited in these soils due to decreased water uptake. We studied the root growth of two subpopulations of alfalfa differing in their ability to produce fibrous roots to determine if altering root morphology would increase plant yield and water extraction, in an irrigated saline soil.

Soil profiles for a control …

Habitat Selection And Movement Of A Stream-Resident Salmonid In A Regulated River And Tests Of Four Bioenergetic Optimization Models, Mark D. Bowen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A bioenergetics model was constructed for stream-resident drift-feeding salmonids. Model predictions of surplus power (energy available per unit time for growth and reproduction) were not statistically distinguishable from observations of surplus power in three laboratory studies. Of 40 experimental trials in these three studies, the model correctly predicted surplus power in 39 cases (p < 0.05).

I collected observations of rainbow trout (Oncorhynchus mykiss) focal velocity and physical habitat availability in the Green River of northeastern Utah, USA (1988-1990). In the winter of 1988, Flaming Gorge Dam generated hydropower and delivered an lJDStable discharge regime with a higher mean discharge …

Mule Deer Highway Mortality In Northeastern Utah: An Analysis Of Population-Level Impacts And A New Mitigative System, Mark E. Lehnert

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Rerouting highways to accommodate construction of the Jordanelle Reservoir in northeastern Utah caused a dramatic increase in vehicle collisions with mule deer (Odocoileus hemionus). I evaluated the effectiveness of a new system of highway crosswalk structures installed to reduce deer losses and preserve seasonal migrations. In addition, I constructed computer simulation models to investigate how highway mortality has impacted the Jordanelle deer population.

The crosswalk system restricted deer crossings to specific, well-marked areas along highways where motorists could anticipate them. Subsequent to installation, mortality declined 42.3% and 36.8% along a four-lane and two-lane highway, respectively. I was unable …

An Ecological History Of Tintic Valley, Juab County, Utah, Jeffrey A. Creque

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This work was a case study of historical ecological change in Tintic Valley, Juab County, Utah, an area historically impacted by mining and ranching activities common to much of the American West. The temporal framework for the study was approximately 120 years, the period of direct Euroamerican influence. In recognition of the ecological implications of cultural change, however, the impacts of prehistoric and protohistoric human activity on study area landscape patterns and processes were also explicitly addressed.

The study included a narrative description of historic land uses and ecological change in Tintic Valley, and examined the changes in landscape patterns …

Livestock As Seed Disseminators For Reseeding Degraded Rangelands: The Role Of Dung In Gap Formation And Plant Establishment, Brian S. Auman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Livestock (cattle and sheep) were examined as seed disseminators for reseeding degraded Intermountain rangelands. "Hycrest" crested wheatgrass [Agropyron desertorum (Fisch. ex Link) Schult. X A. cristatum (L.) Gaert.] seed was fed to yearling Holstein steers and Suffolk ewes. Dung was collected from each animal type and deposited on plots of high and low densities of an annual [cheatgrass (Bromus tectorum L.)] and perennial [squirreltail (Sitanion hystrix Nutt.)] grass species. The experiment evaluated the ability of the dung to suppress the resident vegetation, and the recruitment and establishment of Hycrest seedlings emerging from the dung.

Sheep dung had …

Growth Responses Of Great Basin Plant Species To Variation In Nitrogen Availability, Carol J. Bilbrough

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

For this dissertation, I examined the ability of field-grown plants to capture N presented in enriched patches or in whole-plant pulses. I assessed root proliferation in N-enriched patches when Agropyron desertorum plants had been previously fertilized or shaded. All plants responded with increased root growth rates in N-enriched patches. However, root proliferation by shaded plants was 50% less than unshaded plants. Unexpectedly, plants with higher N status had greater root growth rates in enriched patches than plants that had not received N supplement. I concluded that plants already under competitive pressure above ground for light and below ground for nutrients …