Digital Commons Network^™

Big Game Depredation To Crops And Orchards In Seven Counties Of Northern And Central Utah: A Case Study, Kerry C. Mcbride

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Depredation to crops and orchards is a problem for agricultural producers in many states where big game are in close proximity to land used for ag-production. Heavy snowfall has created a serious big game depredation in Utah in recent years. Heavy snowfall covers big game feed during winter months, which creates a serious demand on cultivated land to maintain the big game herds at current levels. Many operators believe that current big game herd sizes are too large available feed, and should be reduced to prevent damage to agricultural production. Many big game managers believe otherwise.

This study looked at …

The Feasibility Of River Otter Reintroduction In Northern Utah, Joel P. Bich

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this thesis is to document river otter (Lutra canadensis) distribution and reintroduction potential in northern Utah. Distribution was studied using data from 3 sources: 1) otter sighting records from Utah Division of Wildlife Resources; 2) surveys of Utah furbearer trappers and natural resources personnel; and 3) searches of streams for otter sign. Potential for river otter habitat/reintroduction was evaluated by assessing food, cover, and reintroduction attributes. Streams were ranked using an evaluation system based on data from the otter literature.

Forty-six positive otter sightings were made in Utah by trappers, natural resources personnel, and the …

Factors Affecting Recovery From Defoliation During Drought In Two Aridland Tussock Grasses, Carlos Alberto Busso

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The importance of several factors in limiting recovery from defoliation was investigated in field-grown plants of Agropyron desertorum and Agropyron spicatum exposed to drought , natural or irrigated conditions. Leaf extension rate, components of leaf area production, number of metabolically active axillary buds and carbohydrate availability were examined on the same plants immediately after defoliation and/or in the following spring from 1984 until 1986.

The diurnal course of leaf growth did not relate to turgor pressure in the expanded portion of leaf laminae. Rather growth was apparently associated with air temperature. Leaf extension rate was lower under drought than under …

Acquisition Of Forgaging Skills By Lambs Eating Grass Or Shrub, Enrique R. Flores

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I studied the acquisition of foraging skills by lambs eating shrub or grass in three experiments. The general approach was to isolate those skills involved in prehending forage from those related to the acceptance of novel foods. Treatment lambs received 15 times more exposure to grass or shrub than did control lambs. Lambs were tested in 2.5 x 2.5 meter monocultures of shrub or grass 5 min/d, on two separate occasions. Height, bulk density and spatial arrangement of plant material were controlled during testing.

In Experiment 1, I studied the acquisition of foraging skills by lambs on monocultures of shrubs. …

Bioavailable Phosphorus In The Bear River System, Utah, Kenneth Warren Barker

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The bioavailable fraction of phosphorus (BAP) in the lower Bear River system waters was investigated. BAP plays a critical role as the limiting nutrient for algal production and eutrophication in proposed reservoirs in the Bear River system. The Bear River system has a hardness ranging between 180-240 mg/L as CaCO₃ which significantly affects BAP.

BAP estimation was done by a modified Selenastrum capricornutum Printz Algal Assay Bottle Test. The algal bioassay is considered the best estimator of BAP because no chemical tests or indicator parameters are available. Autoclaving and UV radiation were found to be unacceptable means for sterilization …

Patterns Of Singing By House Wrens With Respect To The Breeding Cycle, Michael H. Tove

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I recorded the songs and studied the reproductive behavior of a population of marked House Wrens (Troglodytes aedon) to identify patterns of singing and correlate them with behavioral contexts and stages of the breeding cycle. I found that House Wren singing could be organized into three hierarchical regimes: routine patterns of daily singing, context-specific patterns of singing and long-term fluctuations in singing rate throughout the breeding cycle. During routine daily singing, predictable structural changes occurred. Songs were clustered in discrete groups called bouts. The songs within a bout were more similar in structure than songs from different bouts. …

Durational Control Of Defensive Burying In Rats: An Investigation Of A Species-Specific Defense Reaction, Stephen Gregory Goldberg

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Six experiments were run to determine whether the duration of conditioned defensive burying (COB) in rats is a function of its consequences.

Four experiments developed the methodology. Experiment 1 replicated the standard one-trial experiment, where rats are shocked once by a prod. All three rats exhibited CDB. Experiment 2 used a lever-press-for-water contingency to force recontact with the lever, following shock deliveries in Sessions 6 and 14. All three rats buried the lever in both sessions. Experiment 3 replicated Experiment 2, employing albino and hooded rats. All six buried the lever. The albinos exhibited longer burying durations. Experiment 4 used …

Structure-Activity Relationships Of Retinoids In Developmental Toxicology, W. Brian Howard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The teratogenic potency of retinoid analogs was determined in Syrian hamsters and compared to the teratogenic potency of all-trans-retinoic acid (all-trans-RA, ED₅₀ = 10.5 mg/kg). A total of 15 analogs having variations in the cyclohexene ring were evaluated following various amounts of single oral doses on day 8 of gestation. Retinoids containing a five- or six-membered ring were as teratogenic as all-trans-RA, provided they had sufficient lipophilic substituents on the ring. The same pattern emerged for retinoids that had six-membered aromatic ring substitution for the natural cyclohexene ring of vitamin A. Incorporation of a supplementary …

The Role Of Homeostatic Imbalance In The Reported Immunomodulation Of T-2 Toxin, Michael Jay Taylor

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

T-2 toxin (T-2), produced by the genus Fusarium, is a cytotoxic trichothecene mycotoxin, a feed contaminant, and has been shown to be immunomodulatory. It is suspected that T-2-associated immunomodulation is mediated partly through the hypothalamic-pituitary-adrenal axis. The presence of endotoxin, a bacterial product capable of activating the hypothalamic-pituitary-adrenal axis as well as the levels of several hormones, also associated with activation of the hypothalamic-pituitary-adrenal axis, were determined in both vehicle- and toxin-treated animals. Endotoxemia was evident twenty-four hours after a single oral exposure to T-2. Blood levels of adrenocorticotropic hormone and corticosterone, parameters of the stress response, also increased …

Interactions Of Vanadium Compounds With Reducing Equivalents: Evidence Of Free Radical Involvement And Possible Mechanisms Of Toxicity, Randal J. Keller

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Vanadium compounds have been reported to cause numerous toxicological effects including NAD(P)H oxidation and lipid peroxidation. The purpose of this thesis is to determine the active form of vanadium in causing these effects, and to determine any possible free radical involvement in these processes. Vanadium-stimulated oxidation of NADH was studied spectrophotometrically and by electron spin resonance spectroscopy. In 25 mM sodium phosphate buffer at pH 7. 4, vanadyl, (V(IV)), is slightly more effective in stimulating NADH oxidation than was vanadate (V(V)). Addition of a superoxide generating system, xanthine/xanthine oxidase, results in a marked increase in NADH oxidation by vanadyl, and …

Luteinizing Hormone An Progesterone Response To Gnrh Administration At Insemination In Repeat-Breeder Holstein Cows, Robert Joseph Callan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Several studies suggest that the administration of GnRH near the time of insemination improves pregnancy rates in cattle. It has also been reported that there is greater improvement in repeat-breeder animals than at first service. The mechanism for this observation has not been established. Twenty-eight lactating Holstein cows that returned to estrus after one or more inseminations from the USU Caine Dairy were used in the study. Animals were randomly divided into two treatment groups, intramuscular administration of 100 ug GnRH or saline control at the time of insemination. Blood samples were collected at 1, 1.5, 2, 2.5, 3 and …

The Immunological And Neurochemical Toxicity Of Benzene And Its Interaction With Toluene In Mice, Gin-Chang Hsieh

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Benzene and toluene are known groundwater contaminants . Male CD-I mice were continuously exposed to 0, 31, 166, and 790 mg/ L benzene and 0, 17, 80, and 405 mg/L toluene, respectively, in drinking water for four weeks. Benzene caused a reduction of leukocytes, lymphocytes and erythrocytes, and resulted in a macrocytic anemia. Lymphocyte response to both B- and T-cell mitogens, mixed lymphocyte response to alloantigens, and the ability of cytotoxic lymphocytes to lyse tumor cells were enhanced at the lowest dose of benzene and depressed in the higher dosage animals. Benzene at doses of 166 and 790 mg/L decreased …

Characterization Of Chemical And Radiation-Induced Dna Damage In The Mdbk Cell Culture System, Jeffrey R. Hincks

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A mechanism common to many carcinogens and mutagens is the interaction with cellular DNA. Alkaline elution is a sensitive and commonly used technique to detect cellular DNA damage in the form of DNA single-strand breaks (SSB), DNA-protein cross-links (DPC), and DNA interstrand cross-links (ISC). In the present study, gravity-flow alkaline elution was developed and validated to rapidly detect DNA damage in the MDBK cell culture system by genotoxic agents.

The system was first validated by detecting a dose dependent induction of DNA SSB in cells exposed to 25-1500 rad of X-ray. The assay reliably detected the DNA damage of seven …

Synthetic Studies Toward Key Portions Of The Didemnins, Ok-Soon Kim

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Three different synthetic approaches toward N-[(2SR, 4S) - 4-hydroxy-2,5-dimethyl-3-oxohexanoyl]-Lleucine methyl esters were carried out by use of i) aldol condensation and amination ii) Claisen condensation and soft acid coupling reaction iii) methylation of Hia-Leu derivative in relatively high yields. (4S)-3-[(2SR, 4S)-2,5-Dimethyl-1,3-dioxo-4-(methoxyethoxy-methyloxy)hexyl]-4-(1-methyletheyl-2-oxazolidinone was prepared by the reaction of aldol condensation of lithium enolate of Evans' chiral auxilary in 80:20 diastereomeric ratio. A new method for the synthesis of (4S)-4-(t-butoxycarbonyl)amino-5-methyl-3-oxoheptanoic acid ethyl ester (Statone) was developed by the reaction of Boc-leucine with Meldrum's acid, followed by transesterification and decarboxylation in modest yield. Other a-amino acids also were applied to this methodology in …

Alfalfa Weevil, Hypera Postica (Gyllenhal), (Coleoptera: Curculionidae) Response To Environmental Factors In Alfalfa Fields In Northern Utah, Larry Edward Jech

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Economic damage to forage alfalfa by the alfalfa weevil occurs frequently enough in northern Utah to warrant applications of an insecticide in some years but not all. Currently a five to ten day period is available to recognize injurious populations then make applications.

Sticky boards, pitfall traps, Berlese funnels sweep samples, stem bouquets, climatic variation and marking techniques were evaluated for alfalfa weevil population predictions. The prevailing climate was the most important factor controlling early adult activities. Early adult feeding and sexual development was the key to forecasting later larval populations. Regional surveys were not adequate for local control recommendations. …

Characterization Of Esterases And Glutathione S-Transferases In A Solitary Bee, Megachile Rotundata (Fab.): Variability, Developmental Multiplicity, Substrate Specificity, And Inhibition, Donald R. Frohlich

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The esterases and glutathione S-transferases of a solitary bee, Megachile rotundata (Fab.) (Hymenoptera: Megachilidae), the alfalfa leafcutting bee, were characterized by electrophoresis, substrate specificity, and inhibition studies. Comparisons were made between ages, sexes, and life stages for several classes of substrates and their isomers: aromatic, aliphatic, and thio-esters. Two esterases were found to be allozymes and variable between individuals and sexes. Adults typically possess an esterase that hydrolyzes fluorescent substrates, an organophosphate insensitive esterase, and a series of type 'B' esterases that are very sensitive to organophosphate inhibition. Electrophoretic patterns are different between adults and immatures and are probably …

Control And Evaluation Of Big Game Browsing Damage To Commercial Fruit Orchards, William E. Stone

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Diversionary feeding, artificial feeding designed to divert animals away from areas where they might cause property damage, was tested for efficacy in reducing fruit orchard browsing by big game animals during two consecutive winters in Utah. Strategically placed attractive feedstuffs lured deer to feed stations and reduced fruit-bud browsing (1st year, P < 0.07; 2nd year, P < 0.01). Blossom and apple numbers were greater (P < 0.05) on trees in the feed (treatment) orchard than in the no feed (control) orchard in each year. However, higher (P < 0.05) apple production on trees where browsing was excluded in the treatment orchards compared to the control orchards indicated that intercept feeding did not increase crop production. Tree periodicity and other factors affecting apple production masked the effect of diversionary feeding on crop yield.

Two independent browsing damage assessment methods, a paired-tree technique and a harvest-inflation technique, predicted that the ratio of apples lost per browsed bud was 0.158 and 0.082, respectively. However, the values of the ratio varied widely with each method of estimation. Browsing damage differed ( …

The Effects Of Forest Harvesting On Small Mammals In Western Newfoundland And Its Significance To Marten, Brian Tucker

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The depauperate fauna of Newfoundland provides a limited prey base for marten. Only two small mammal prey species, Microtus pennsylvanicus and Sorex cinereus, were found in any abundance in the old-growth forests of the study area. Of these two, Microtus displayed population fluctuations typical of most microtines. Analysis of marten scats indicated that Microtus is a very important prey item to the marten with other food. items being of lesser importance particularly when Microtus are abundant.

Trapping in various habitats indicated that Sorex densities were three to five times higher in logged areas compared to uncut areas. Unfortunately, the …

A New Approach To Forest Site Quality Modeling, David L. Verbyla

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Multiple regression and discriminant analysis procedures are commonly used to develop forest site quality models. 'When they contain many independent variables relative to sample size, these models may be subject to predicton bias. Fit statistics such as R² in regression and classification tables in discriminant analysis show the apparent model accuracy but this may be a biased estimate of the model's actual accuracy. Sample splitting methods such as cross-validation and the bootstrap can be used to get an unbiased actual accuracy estimate.

A discriminant procedure called classification tree analysis uses cross-validation to build the classifier with the greatest estimated …

Nutrient And Water Interrelationships Between Crested Wheatgrass And Two Shrub Species, Paul B. Baker

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

When crested wheatgrass (Agropyron desertorum) grows in mixture with sagebrush (Artemisia tridentata), its production declines. Its production increases when grown in mixture with fourwing saltbush (Atriplex canescens), according to previous reports. This study investigated soil water extraction and potassium (K) nutrition of the two shrubs to identify possible causes of the differential responses of crested wheatgrass.

Crested wheatgrass had reduced, rather than increased, nitrogen (N) and K yield in mixture with fourwing saltbush. No differences in N and phosphorous (P) concentrations were observed between sagebrush and fourwing saltbush, but fourwing saltbush had a much …

A Model Of Energy Expenditure In White-Tailed Jackrabbits (Lepus Townsendii) Based On Integrated Studies Of Energetics And Field Ecology, Gordon L. Rogowitz

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Field and laboratory studies were conducted to develop a model of energy expenditure in a population of white-tailed jackrabbits (Lepus townsendii). Field work in southwestern Wyoming during 1985-87 showed that the breeding season commenced at snowmelt and ceased during late- July drought. Adult females reproduced relatively synchronously and produced a mean of three litters annually. Greatest fetal production occurred in the second litter period. Collections indicated a 1:1 sex ratio, few jackrabbits >2 years-old, and a density of 7 animals / km² in the population. Postnatal growth was sigmoidal, culminating in heavier adult females than males. Using …

Nesting And Habitat Parameters For Selected Raptors In The Desert Of Northwestern Utah, David L. Peterson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study examined the effects of habitat parameters, disturbances and predation on the reproductive success of golden eagles (Aguila chrysaetos), ferruginous hawks (Buteo regalis), red-tailed hawks (Buteo jamaicensis) and prairie falcons (Falco mexicanus) in the desert area southwest of the Great Salt Lake in northwestern Utah.

The prairie falcon was the only species examined that had a normal reproductive output during the study years of 1984-1986. The prairie falcon was better able to utilize the avian prey species which were very difficult for the larger and slower raptor species to capture. During …

Effect Of Fertilization On Woody Plant Chemistry: The Role In Diet Selection By Goats, Amanuel Gobena

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Lack of forage quantity and quality limit livestock production during the dry season in northeast Brazil. Coppice produced following cutting of tree species in this area has the potential to increase forage quantity and quality during the dry season, because trees that coppice retain green foliage throughout most of the dry season. However, the palatability of coppice is often low.

From a theoretical standpoint, woody plants with inherently slow growth rate should be less palatable to herbivores than plants with inherently fast growth rates, because plants that grow slowly allocate more carbon to compounds such as tannins and resins that …

Inter-Seasonal Range Relationships Of Spanish Goats And Mule Deer In A Utah Oakbrush Community, Robert Alexander Riggs

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Three experiments were conducted to assess the potential for using Spanish goats to manage Gambel oakbrush winter range, dominated by Gambel oak (Quercus gambelii), for mule deer (Odocoileus hemionus). Summer-time food selection of goats, effects on plant community composition, and consequent effects on mule deer nutrition and foraging behavior were examined.

An apparent preference for juvenile oak browse, and low use of oak twigs was observed. Selection for juvenile browse may have been facilitated by the retarded phenology of oak as compared to that of associated flora. This differential was maintained by repeated browsing. Animal performance, …

Occurrence Of Vesicular-Arbuscular Mycorrhizae In Degraded Rangelands And Physiological Responses Of Six Agropyron Cultivars To Infection, Di Jian Jun

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Physiological and morphological responses of six Agropyron cultivars to vesicular arbuscular mycorrhizal (VAM) inoculation were measured in the greenhouse. These included diploid, tetraploid, and hexaploid cultivars. Plants had up to 94% infection after three months. The two diploid cultivars (A. cristatum (Fairway) and A. puberulum) had the fastest rate of infection. With VAM infection the two diploid cultivars were significantly reduced in rood biomass and had lower water use efficiency than without infection. Phosphorus concentration of mycorrhizal plants was significantly higher in shoots of four or the six cultivars. Carbon dioxide gas exchange rate, transpiration rate, stomatal resistance …

The Bioavailability Of Iron From Meat, Spinach, Soy Protein Isolate, Meat:Spinach And Meat:Spi Mixtures Fed To Anemic And Healthy Rats, Dejia Zhang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Two Experiments were conducted to investigate the effect of iron status and iron source on iron bioavailability using the rat model. Beef was proportionally mixed with spinach (Experiment I) or soy protein isolate (Experiment II) to test if meat enhances the absorption of iron from spinach or SPI. Five diets with the iron from meat:spinach (or SPI) ratios of 100:0, 75:25, 50:50, 25:75 and 0:100 were prepared and fed to rats. FeS04 was used as a reference. Two trials of rats were used in Experiment I. In trial I, half of the rats were made severely iron deficient (Hb 6.3 …

Family Background And Personal Characteristics As Correlates Of Sexual Intercourse Experience Among Adolescent Females, C. Raymond Bingham

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A sub-sample of 814 nonvirgin, adolescent females was drawn from the 1979 U.S. National Survey of Young Women in order to study the correlates of age at first sexual intercourse. This sample was analyzed using a conceptual model developed from past research, as well as some intuitively interesting associations meriting investigation.

Multiple regression procedures were used in analysis of variables by block. In the block analysis several variables were found to predict age at first sexual intercourse. These variables included all the control variables (respondent's age, race, religion, and age at menarche), household income, ideal age for first marriage, ideal …

Gambel Oak For Spanish Goats: A Digestion-Balance Evaluation Of Nutrient Availability, Brian L. Dick

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Fresh-harvested Gambel oak (Quercus gambelii) browse was mixed with chopped alfalfa hay to formulate six diets, varying in oak content at two phenological stages. Diets included juvenile oak (65,80,95%), mature oak (40,80%), and an alfalfa control. Diets were evaluated for goats using a series of total-collection digestion balance trials. Dry matter intake was highest for animals on mature oak diets, and lowest on diets containing a high percentage of juvenile oak, possibly due to differences in diet dry matter content. Apparent digestibility of dry matter and cell wall components was lowest for mature oak diets, and highest for …

Problems Of Data Collection For Economic Research In Small Farmer Agriculture: Some Experience In Somalia, Aden Abdullahi Aw-Hassan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purposes of this thesis are twofold. The first is to show problems encountered in collecting and analyzing data on small-holder agriculture. The second is to describe the role of data in supporting research and rationalization of alternatives for sustaining agricultural strategies in development.

Data collected from six villages of the Lower Shebelle Region of Somalia are taken as a case study to show the difficulties encountered in procurement and analysis of that data. The thesis discusses data collection methods that ensure gathering adequate data that can be used to undertake production economics and farm management research. The thesis also …

Nitrogen And Energy Budgets Of Production Ewes On Summer Range In Southwestern Utah, John W. Halpop

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nitrogen (N) and energy budgets for free-roaming ewes were quantified on mountain summer range in southwestern Utah in 1986 and 1987. Diet quality (%N), in vitro organic matter digestibility (IVOMD), and energy were estimated with the use of five esophageally fistulated ewes. Excretion rates of N and energy to feces and urine were measured by total collection from five nonfistualted ewes.

Total intake N(gN/(MBW*d^-1) tracked intraseasonal changes of dietary N percent but was apparently buffered by fluctuations in dry matter intake. In each year, total urine N was closely related to dietary N concentration, r²=0.97 (1986) …