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Evaluation Of The Early Establishment Phase Of Agropyron Desertorum, Medicago Sativa And Atriplex Canescens In Monocultures And Mixtures, Oscar Luis Prado Escobar May 1983

Evaluation Of The Early Establishment Phase Of Agropyron Desertorum, Medicago Sativa And Atriplex Canescens In Monocultures And Mixtures, Oscar Luis Prado Escobar

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study evaluated the early establishment phase of various monocultures and mixed species plantings of Agropyron desertorum (AGDE), Medicago sativa (MESA), and Atriplex canescens (ATCA). The study was conducted under both greenhouse and field conditions. In the greenhouse, the experimental design was a split-plot, randomized-block design in time, using transplanted seedlings. The treatments were exposed to three water levels to determine species response to varying moisture availability. Plastic pots of 15.4 cm (diameter) by 17.9 cm (depth) were filled with 2,800 g of sandy-loam soil and brought to field capacity. The pots were weighted twice weekly and the water lost …


Using Videodisc Technology And The Index Of Nutritional Quality To Teach Dietary Guidance To Young Adults, Glenda Wigginton Edmunds May 1983

Using Videodisc Technology And The Index Of Nutritional Quality To Teach Dietary Guidance To Young Adults, Glenda Wigginton Edmunds

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A review of the literature indicated a need for nutrition education materials to be current with prevailing scientific knowledge, using advanced instructional technology. Individuals need help in applying nutrition principles to their dietary practices.

A nutrition education program utilizing the nutrient density concept and the dietary guidelines for use on videodisc with microcomputer interface was developed and evaluated. The evaluation of the program did not prove to be effective statistically but learners did show an interest in the program and had positive feedback in regard to the information presented and the technology used.


Efficiency Of Converting Iron Into Hemoglobin As An Assay For Evaluating Iron Bioavailability, Paul Whittaker May 1983

Efficiency Of Converting Iron Into Hemoglobin As An Assay For Evaluating Iron Bioavailability, Paul Whittaker

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effect of iron absorption on subsequent hemoglobin regeneration was investigated by repletion and subsequent analysis of an anemic weanling rat model. Primary assay procedure in these studies was the Regeneration Efficiency method.

As repletion or curative assay techniques form the central body of investigative research in iron utilization, the first subject of inquiry was the effect of repletion interval and degree of depletion upon the animals as monitored by physical indicators such as blood volume, growth and hematinic response. Percent blood volume is a particularly useful figure in the calculation of the amount of hemoglobin iron but was found …


Plant Responses To Clinostating And Mechanical Stress: Growth And Flowering Responses, Chauncy Steed Harris May 1983

Plant Responses To Clinostating And Mechanical Stress: Growth And Flowering Responses, Chauncy Steed Harris

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Plants rotated about a horizontal axis show certain growth responses. This research was designed to clarify which of the responses of clinostating are caused by gravity compensation and which are caused by mechanical stresses. Plants used were Xanthium strumarium L. (cocklebur) Chicago strain and Lycopersicon esculentum Mill. (tomato) cv. Rutgers. Six automated treatments that ran for five days were used to separate out the effects. Treatments were: 1) controls, 2) horizontal clinostat, 3) intermittent clinostat, 4) inversion (every 10 min), 5) invert and return, and 6) vertical rotation. Plant height and diameter changes were measured at ink dots with a …


Applying The Concept Of Feeding Stations To The Behavior Of Cattle Grazing Variable Amounts Of Available Forage, Enrique R. Flores May 1983

Applying The Concept Of Feeding Stations To The Behavior Of Cattle Grazing Variable Amounts Of Available Forage, Enrique R. Flores

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A quantitative description of the foraging process is necessary for effective planning and execution of intensive grazing schemes. Foraging behavior is defined as having two components: feeding and moving. At intervals the foraging animal walks a number of steps searching for food and then pauses to feed at a new position here termed a feeding station. Five behavioral variables were analyzed under this framework: 1) time spent at a feed ing station; 2) number of bites at a feeding station; 3) steps taken between stations; 4) rate of steps; and 5) foraging time. The experimental design consisted of grazing small …


Effects Of Physical And Emotional Stress, Catecholamines And Naloxone On Hdl And Ldl Cholesterol Levels In Rats And Man, Andrew G. Goliszek May 1983

Effects Of Physical And Emotional Stress, Catecholamines And Naloxone On Hdl And Ldl Cholesterol Levels In Rats And Man, Andrew G. Goliszek

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A series of investigations were undertaken to determine whether physical or emotional stress, catecholamines or naloxone (B-endorphon blocker) would increase serum total cholesterol and LDL and HDL levels. Physical stress given daily over a period of time caused a steady increase in serum total cholesterol and LDL without a significantly altering high density lipoproteins (HDL) or serum triglycerides. Daily injections of epinerphrine in oil caused an increase in both serum total cholesterol and LDL levels while daily injections of norepinephrine did not. Reversal of the treatments caused a reversed response in both groups of rats. Similar increases in both total …


Toxicity Of Bacillus Thuringiensis Var. Israelensis Crystals To Aedes Aegypti Larvae: Carbonate Reversal, Danny J. Schnell, Kenneth Nickerson May 1983

Toxicity Of Bacillus Thuringiensis Var. Israelensis Crystals To Aedes Aegypti Larvae: Carbonate Reversal, Danny J. Schnell, Kenneth Nickerson

Papers in Microbiology

The toxicity of purified Bacillus thuringiensis var. israelensis crystals to larvae of Aedes aegypti could be reversed 100-fold by levels of K2CO3 as low as 0.15%.


Direct Optical Scanning Gel Chromatography: Improvements To The Technique And Application To Several Diverse Biochemical Problems, John Grothusen May 1983

Direct Optical Scanning Gel Chromatography: Improvements To The Technique And Application To Several Diverse Biochemical Problems, John Grothusen

All Dissertations

No abstract provided.


Nest Success And Nesting Habits Of Eastern Kingbirds And Other Flycatchers, Michael T. Murphy May 1983

Nest Success And Nesting Habits Of Eastern Kingbirds And Other Flycatchers, Michael T. Murphy

Biology Faculty Publications and Presentations

Patterns of nest placement and its relationship to nest success in the Eastern Kingbird (Tyrannus tyrannus) were studied in populations breeding in New York and Kansas. Data were augmented with information on nest placement in other open-nesting tyrannids in order to examine the hypothesis that these flycatchers place their nests chiefly so as to conceal them from predators. Nesting success was significantly greater in New York than in Kansas but was relatively high in both populations, as is apparently true of North American breeding flycatchers in general. Geographic variation in nest placement in the Eastern Kingbird was relatively small and …


Differential Behavior Of Coyotes With Regard To Home Range Limits, Charles E. Harris May 1983

Differential Behavior Of Coyotes With Regard To Home Range Limits, Charles E. Harris

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study was conducted to examine coyote behavioral responses to novel stimuli in familiar and unfamiliar environments and the implications of this behavior with regard to specific coyote management and research techniques. A series of pen studies with captive coyotes was undertaken at the U.S. Fish and Wildlife Service's Predator Ecology and Behavior Project research site, Logan, Utah, to observe the range and type of behaviors coyotes showed towards small novel objects and standard scent stations in familiar and unfamiliar 1-ha enclosures. The initial response to these novel stimuli in familiar environments was one of neophobia and caution, whereas in …


The Effects Of So2 On N2-Fixation, Carbon Partitioning, And Yield Components In Snapbean, Phaseolus Vulgaris L., Stephen M. Griffith May 1983

The Effects Of So2 On N2-Fixation, Carbon Partitioning, And Yield Components In Snapbean, Phaseolus Vulgaris L., Stephen M. Griffith

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The primary air pollutant sulfur dioxide has been shown to affect plant biochemistry and physiology, although very little is known about its effects on N2-fixation in legumes.

This study was designed to determine if N2-fixation, carbon partitioning , and productivity are affected under short term low level, so2 exposures.

Greenhouse grown snapbeans (Phaseolus vulgaris L. cv. Earliwax), 29 days from planting, were exposed to 0.0, 0.4, and 0.8 parts per million sulfur dioxide for 4 hours day-1 for 5 days in a fumigation chamber. At these concentrations there was no visible damage of …


The Photoregulation Of Phenylpropanoid Metabolism And Amino Acid Accumulation In Triticum Aestivum (Var. Fremont), Daniel J. Guerra May 1983

The Photoregulation Of Phenylpropanoid Metabolism And Amino Acid Accumulation In Triticum Aestivum (Var. Fremont), Daniel J. Guerra

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Wheat (Triticum aestivum L.) grown in controlled environments with a 24-hour photoperiod was analyzed for phenylpropanoid and amino acid metabolites. Discrete spectral environments, including a metal halide, high-pressure sodium and low-pressure sodium lamps, provided both photosynthetically active radiation and phenylpropanoid inducing fluences of light. A greenhouse spectral environment supplemented with fluorescent lamps was also used to culture wheat. All four spectral environments were used to culture wheat to maturity separately. The activities of phenylalanine and tyrosine ammonia-lyase were photoinduced in wheat tissue obtained from plants grown in the metal halide, high-pressure sodium and greenhouse spectral environments. These enzyme activities are …


Use Of Clearcut Habitats By Black Bears In The Pacific Northwest, Kim R. Barber May 1983

Use Of Clearcut Habitats By Black Bears In The Pacific Northwest, Kim R. Barber

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Patterns of vegetation use by black bears (Ursus americanus) on Long Island, Washington were documented using radio-telemetry in 1973-74 and 1980-81. Secondary succession altered the vegetative compostion of clearcut areas through this time, reducing the areas dominated by productive brush species by nearly 50%. Seasonal food habits, consisted primarily of grasses and forbs in spring (den emergence-May) and flowers and fruits of shrub species in summer (June-September) and fall (October-den entrance).

Bears selected for clearcuts (5-21 years of age) over all other vegetation types for feeding but preferred areas dominated by large trees when inactive during both the …


The Effect Of Heat Treatment On Meat Heme And Nonheme Iron Bioavailability For The Anemic Rat, Oranong Jansuittivechakul May 1983

The Effect Of Heat Treatment On Meat Heme And Nonheme Iron Bioavailability For The Anemic Rat, Oranong Jansuittivechakul

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Three separate experiments were conducted to investigate the effects of heat treatment on meat heme and nonheme iron bioavailability in anemic rats. Male weanling Sprague-Drawley rats were first made anemic, then subsequently fed with experimental diets. In the first experiment, dietary iron sources were raw or autoclaved meat mixed with ferrous sulfate to give the ratios of iron from meat and ferrous sulfate equal to 100:0, 75:25, 50:50, 25:75, and 0:100 respectively. For the second experiment, the dietary iron sources were raw or autoclaved meat mixed with bovine hemoglobin (HB) to give dietary iron ratios as described for experiment 1. …


A Study Of The Action Of Bovine Cathepsin D On Intramuscular Connective Tissue, Elimosaria Elikalia Maeda May 1983

A Study Of The Action Of Bovine Cathepsin D On Intramuscular Connective Tissue, Elimosaria Elikalia Maeda

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Cathepsin D has been postulated to play a role in the tenderization of meat with ageing. Meat toughness has been related to connective tissue content and degree of myofibrillar shortening. This investigation was undertaken to determine the activity of cathepsin D on bovine intramuscular connective tissue.

Highly purified cathepsin D preparations from bovine spleen and bovine sternomandibularis muscle were obtained by ammonium sulfate fractionation followed by affinity chromatography on pepstatin coupled to controlled pore size alkyl amine glass beads. Maximum proteolytic activity using hemoglobin as substrate was obtained at pH 3.5 and 3.8 for bovine spleen and muscle cathepsin D, …


Longitudinal Pantothenic Acid Status Of Pregnant And Lactating Women, Won Oack Song May 1983

Longitudinal Pantothenic Acid Status Of Pregnant And Lactating Women, Won Oack Song

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Pantothenic acid nutritional status was evaluated in a cohort of twenty-nine Caucasian pregnant women, aged 20-35, during their third trimester of pregnancy, at two-weeks postpartum and at three months postpartum. Seventeen non-pregnant, non-lactating women who had similar demographic backgrounds as the pregnant women were selected as a control group and followed the same experimental schedule as the pregnant women. A fasting blood sample, two days 24-h urine specimens and diet record were obtained for each of two days from each subject at each period.

The mean dietary pantothenic acid intakes of the women during pregnancy (5.30±1.74 mg/day) and during lactation …


Enzymic Milk Coagulation: Casein Micelle Aggregation And Curd Formation, Donald J. Mcmahon May 1983

Enzymic Milk Coagulation: Casein Micelle Aggregation And Curd Formation, Donald J. Mcmahon

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Enzymic milk coagulation was monitored by measuring changes in curd firmness and apparent absorbance of undiluted milk. Detection of coagulation, visually or rheologically, occurred after the milk changes from a system of aggregating particles to an extended space network. This change was observed as a shoulder in apparent absorbance plots and coagulation time was defined as the critical point in the aggregation process analogously to non-linear condensation polymerization reactions. It corresponds to the inflexion point during the period when apparent absorbance was rapidly increasing and can be calculated by fitting curd firmness data to an exponential equation.

Addition of calcium …


A Method For Separating Casein Micelles From Whey Proteins For Determining Casein In Milk, Robert N. Carpenter May 1983

A Method For Separating Casein Micelles From Whey Proteins For Determining Casein In Milk, Robert N. Carpenter

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to determine if size exclusion chromatography could be used to separate casein micelles from whey proteins for a rapid, direct test to measure percent casein in milk. A size exclusion chromatography column was developed for the separation having dimensions 100 by .4 cm. Packing material selected was glycophase coated porous glass supports. A Beckman DU-8B spectrophotometer monitored the casein and whey protein peaks as they eluted and a Tektronix 4052 computer accepted data points every 4 sec, storing these on tape. Absorbances and areas of each peak were used in the evaluation of samples. …


Rhizosphere N2 Fixation In A Forest Ecosystem In Situ Assays And Evaluation Of The Acetylene Reduction Technique, Inger Börjesson May 1983

Rhizosphere N2 Fixation In A Forest Ecosystem In Situ Assays And Evaluation Of The Acetylene Reduction Technique, Inger Börjesson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In situ assays of N2 fixation activity, using the acetylene reduction technique, were performed in four successional stages of a Northern Wasatch Mountain subalpine forest ecosystem, elevation 2,800 m. Emphasis was made on rhizosphere fixation in association with Antennaria microphylla and Achillea millefolium. The vegetation period was approximately 100 days.

Assays were performed in Saran bags. A defined amount of propane was injected at initiation of the assay and acetylene was generated from CaC2. Samples were analyzed for ethylene and propane. Data were evaluated assuming that the ethylene production was directly proportional to the increase in …


Natural Killer Activity In Gardner's Syndrome, Ann Marie Stembridge May 1983

Natural Killer Activity In Gardner's Syndrome, Ann Marie Stembridge

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Gardner's syndrome is an autosomal dominant disease presenting multiple colonic polyps with a predisposition for malignant change. In addition to colonic polyp formation by early adolescence, extracolonic lesions appear often prior to polyp formation. One theoretical mechanism for the origin of polyps and malignancies in Gardner's syndrome is a genetic defect in the natural killer cell activity of patients with this disease. Natural killer cells are a subpopulation of lymphocytes that spontaneously lyse tumor cells and virally transformed cells. A study was undertaken to determine the natural killer activity of patients with Gardner's syndrome.

A technique termed chromium release was …


Mule Deer Reproduction And Survival In The Lasal Mountains, Utah, Randall B. Smith May 1983

Mule Deer Reproduction And Survival In The Lasal Mountains, Utah, Randall B. Smith

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Mule deer (Odocoileus hemionus) reproduction and survival on the LaSal Mountains, Utah were studied from 1978-81. Reproductive rates were high, suggesting that summer and fall forage quality was adequate and was not responsible for low recruitment observed in recent years. The combined fetal rate, determined from laparotomies and carcasses, was 1.72 for all females older than 1 year (N = 114). Fetal rates were 1.15 for yearlings (N = 20), 1.80 for prime females (2-7 years, N = 78), and 1.75 for old females (8+ years, N = 16). No evidence of breeding was found among fawns (N …


Development And Pathogenicity Of The False Root-Knot Nematode Nacobbus Aberrans And Its Relationship With Heterodera Schachtii And Meloidogyne Hapla On Sugarbeet, Renato Nunzio Inserra May 1983

Development And Pathogenicity Of The False Root-Knot Nematode Nacobbus Aberrans And Its Relationship With Heterodera Schachtii And Meloidogyne Hapla On Sugarbeet, Renato Nunzio Inserra

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Duration of embryogenic development of a Nebraska population of Nacobbus aberrans at 15 and 25 C were 51 and 9-10 days respectively. The first juvenile (J1) molted in the egg and the nematode emerged as J2. Kochia and sugarbeet root leachates did not significantly affect the percent of cumulative egg hatch. Temperature significantly affected juvenile emergence (P= 0.05), as less than 1, 5, and 20% of the eggs hatched at 5, 10 and 15 C, respectively. More than 70% of the eggs hatched at 20 and 25 C. At 25 C, postembryogenic development from egg to egg was …


Alteration In Serum Enzyme Levels, Activity Of Hepatic Monooxygenases, And Hepatocyte Morphology Due To Liver Enzyme Inducers In Microtus Montanus, Jeffrey Robert Hincks May 1983

Alteration In Serum Enzyme Levels, Activity Of Hepatic Monooxygenases, And Hepatocyte Morphology Due To Liver Enzyme Inducers In Microtus Montanus, Jeffrey Robert Hincks

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Microtus sp. have been used in microcosm simulations of polluted environments. In this study, female Microtus montanus (mountain vole), 8 - 12 weeks of age, were pretreated with phenobarbital (PB), ß-naphthoflavone (BNF), or Aroclor 1254 (PCB) for 3 consecutive days. Doses ranged from 5 to 80 mg/kg for each pretreatment, while control animals received saline or corn oil only. The voles were sacrificed 1 day after the last dose of PB and 2 days after BNF and PCB. Hepatic microsomal enzyme activity of aniline hydroxylase (AH), p-nitroanisole-O-demethylase (PNA) and cytochrome C reductase (CCR) were measured in relation …


Effect Of Hindlimb Immobilization On The Fatigability Of Skeletal Muscle, Frank Arthur Witzmann, D. H. Kim, Robert H. Fitts May 1983

Effect Of Hindlimb Immobilization On The Fatigability Of Skeletal Muscle, Frank Arthur Witzmann, D. H. Kim, Robert H. Fitts

Biological Sciences Faculty Research and Publications

The soleus (SOL) and extensor digitorum longus (EDL) muscles of the rat were studied in situ (33.5ºC) after 6 wk of disuse atrophy produced by hindlimb immobilization (IM). IM resulted in depressed peak twitch (Pt) and tetanic (P0) tension as well as a decreased rate of tension development (+dP/dt) and decline (-dP/dt) in the slow-twitch SOL. The fast-twitch EDL was affected to a lesser extent, because only Po (g·cm-2) and Po,-dP/dt (g·cm-2·ms-1) were depressed after IM. Twitch duration, as measured by contraction …


Hemoglobins Of The Cutthroat Trout Salmo Clarki, Jonathan N. Southard May 1983

Hemoglobins Of The Cutthroat Trout Salmo Clarki, Jonathan N. Southard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nine hemoglobins have been isolated from the blood of cutthroat trout. All nine hemoglobins bind oxygen cooperatively and appear to be tetramers with molecular weights of -64,000. The oxygen equilibria and subunit structures of the purified hemoglobins were studied. In addition, the red blood cells of cutthroat trout were examined for the presence of ATP and GTP, which are known to be physiological modulators of hemoglobins in fishes.

Five hemoglobins with isoelectric points from 9.1 to 7.0 are classified as cathodal hemoglobins. These five hemoglobins have identical oxygen binding properties by the criteria tested. All have oxygen equilibria which are …


Subunit Interactions In The Inducible Arginine Decarboxylase From Escherichia Coli B, Catalina N. Depusoy May 1983

Subunit Interactions In The Inducible Arginine Decarboxylase From Escherichia Coli B, Catalina N. Depusoy

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The nature of the subunit interactions in the inducible arginine decarboxylase from Escherichia coli B is of considerable interest because of the observed differences in the catalytic activities of the dimer and the decamer; the decamer is active and the dimer is inactive. To study these interactions, inactive dimers were prepared by sodium borohydride reduction of the E-amino--pyridoxal-P Schiff base. Hybrid decamers were then prepared from varying molar ratios of native and reduced dimers. The hybrid decamers were indistinguishable from native decamers as observed in the analytical ultracentrifuge and on acrylamide gel electrophoresis. Kinetic studies indicated that true hybrids were …


Brown Trout Perception Of Ultraviolet Radiation And Possible Influence On Distribution, Terrence H. Lee May 1983

Brown Trout Perception Of Ultraviolet Radiation And Possible Influence On Distribution, Terrence H. Lee

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Brown trout (Salmo trutta), demonstrated an avoidance response to a range of intensities of artificial ultraviolet radiation in a laboratory setting. UV field measurements were made under a variety of riparian canopies in a mountain river system. UV values at various depth regimes were compared with laboratory response values. Results suggested that ultraviolet light could be a factor in the absence of brown trout in particular habitat types at various times during the daylight hours. Visible light intensity response values were also obtained under the same experimental and field conditions. These data suggested that visible light also could …


The Interaction Of Ultraviolet-B Radiation Stress And Plant Competition In Agricultural Plant Populations, Warren Glenn Gold May 1983

The Interaction Of Ultraviolet-B Radiation Stress And Plant Competition In Agricultural Plant Populations, Warren Glenn Gold

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effect of ultraviolet-B radiation enhancement upon the competitive interactions of two species pairs was studied in the field. Wheat (Triticum aestivum L. 'Bannock') was paired with wild oat (Avena fatua L.) and jointed goatgrass (Aegilops cylindrica Host) to represent competition between species pairs in agricultural situations. Specially modulated ultraviolet lamp systems provided either low ultraviolet-B enhancement (simulation of a 16 % ozone layer reduction based upon the generalized plant action spectrum), high ultraviolet-B enhancement (40 % ozone reduction) or control (ambient solar ultraviolet-B) irradiance.

Ultraviolet-B radiation enhancement significantly altered the competitive interactions of the species pairs. …


Establishment Of Tall Wheatgrass [Agropyron Elongatum (Host) Beav. 'Jose'] And Basin Wildrye (Elymus Cinereus Scribn. & Merr. 'Magnar') In Relation To Soil Water And Salinity, Bruce A. Roundy May 1983

Establishment Of Tall Wheatgrass [Agropyron Elongatum (Host) Beav. 'Jose'] And Basin Wildrye (Elymus Cinereus Scribn. & Merr. 'Magnar') In Relation To Soil Water And Salinity, Bruce A. Roundy

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The potential of basin wildrye (Elymus cinereus Scribn. & Merr. 'Magnar') and tall wheatgrass [Agropyron elongatum (Host) Beav. 'Jose '] to establish on saline, arid rangelands in the Great Basin in relation to soil water and salinity was compared in field and laboratory experiments. Tall wheatgrass had higher emergence and establishment on a nonsaline and a saline soil (electrical conductivity of the saturation extract of 7 dS·m-1) over a range of spring precipitation as simulated by sprinkler irrigation. Basin wildrye will require supplemental irrigation to establish on soils of similar salinity. In the absence of precipitation, …


Sheep Diets And Feeding Behavior In Single And Common Use Grazing Trials On Southwestern Utah Summer Range, George B. Ruyle May 1983

Sheep Diets And Feeding Behavior In Single And Common Use Grazing Trials On Southwestern Utah Summer Range, George B. Ruyle

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A series of grazing trials were conducted on high elevation summer range near Cedar City, Utah. Cattle and sheep were stocked alone and in common in .4 hectare (ha) paddocks. Stocking rates were .76 ha/AUM in 1981 and .60 ha/AUM in 1982. Vegetation measurements were taken before and after grazing treatments to quantify vegetation disappearance. Diet samples were collected from esophageally fistulated sheep in the paddocks before grazing treatments were applied. After a predetermined level of forage utilization was achieved, the paddocks were re-sampled by the esophageally fistulated sheep to examine diets consumed from the forage-reduced vegetation. Behavioral observations were …