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Preparation Of Cultured And Isolated Cells For X-Ray Microanalysis, K. Zierold, D. Schäfer May 1988

Preparation Of Cultured And Isolated Cells For X-Ray Microanalysis, K. Zierold, D. Schäfer

Scanning Microscopy

Various electron microscopical preparation techniques are compared with regard to the preservation of the intracellular element distribution as determined by X-ray microanalysis in scanning and scanning transmission electron microscopy. By use of chemical agents for fixation and dehydration ions are redistributed and washed out. This is also true for freeze-substitution. Whole cells are prepared by cryofixation followed by freeze-drying. Interference of intracellular measurements by extracellular elements can be avoided by appropriate washing the cells before cryofixation. The washing medium has to be carefully selected in order to avoid distortions of the original intracellular element content. These problems are circumvented by …


Enamel Of Yalkaparidon Coheni: Representative Of A Distinctive Order Of Tertiary Zalambdodont Marsupials, K. S. Lester, M. Archer, C. F. Gilkeson, T. Rich May 1988

Enamel Of Yalkaparidon Coheni: Representative Of A Distinctive Order Of Tertiary Zalambdodont Marsupials, K. S. Lester, M. Archer, C. F. Gilkeson, T. Rich

Scanning Microscopy

The enamel of an incisor and a premolar of Yalkaparidon coheni was examined by scanning electron microscopy in fractured and in sectioned, polished surfaces. The enamel of both teeth demonstrated: complete, ovoid and horse-shoe shaped prisms in a Pattern 2 arrangement; a simple parallel prism course; and, enamel tubules in abundance in the premolar but restricted to the innermost enamel in the incisor. Overall, the enamel ultrastructure supports the marsupial affiliation proposed for Yalkaparidon coheni but does not unambiguously ally it with any other order of marsupials.

The observation of a significant ultrastructural difference between the anterior and posterior teeth …


Characterization Of Wolbachia Postica Which Causes Hybrid Incompatibility In Alfalfa Weevil, Sy-Jye Christine Leu May 1988

Characterization Of Wolbachia Postica Which Causes Hybrid Incompatibility In Alfalfa Weevil, Sy-Jye Christine Leu

Biology

The rickettsia Wolbachia postica is the cause of hybrid incompatibility between males of the western alfalfa weevil and females of eastern or Egyptian weevils. Studies were carried out to obtain information about the biochemical and immunological characteristics of this microorganism. Because of the similarity between rickettsia and mycoplasma under the electron microscope, hybridization of DNA from this microorganism with a mycoplasma-specific gene probe confirmed a previous observation that this microorganism is a rickettsia. A rapid and accurate diagnostic assay for the infection of alfalfa weevils by wolbachia has been accomplished by the production of a polyclonal antibody against Wolbachia postica …


Effects Of Macrocyclic Trichothecene Mycotoxins On The Murine Immune System, Brian J. Hughes May 1988

Effects Of Macrocyclic Trichothecene Mycotoxins On The Murine Immune System, Brian J. Hughes

Biology

The macrocyclic trichothecenes are a unique group of toxins which have some antileukemic properties. In the first study, verrucarin A and roridin A were examined. Both mycotoxins were administered intraperitoneally at an equitoxic dose of 0.35 mg/kg to CD-1 mice. Lymphocyte proliferation was studied on days 2, 4, and 7 after animals were dosed with verrucarin A. After day 2, no differences in 3HThymidine (3H-TdR) incorporation were observed using concanavalin A (Con A), phytohaemagglutinin (PHA), pokeweed mitogen (PWM), or lipopolysaccharide (LPS). On day 4, DNA synthesis induced by Con A, PHA, and PWM increased significantly. On day …


Elicitor Activity From The Ectomycorrhizal Fungus Rhizopogon Vinicolor, Margaret E. Coleman May 1988

Elicitor Activity From The Ectomycorrhizal Fungus Rhizopogon Vinicolor, Margaret E. Coleman

Biology

Culture filtrate and mycelial surface components of the ectomycorrhizal fungus Rhizopogon vinicolor were partially purified by ion exchange and gel filtration chromatography and characterized. These Rhizopogon vinicolor components induced accumulations of condensed phenolics in treated conifer and benn calli and bean cotyledons. The treated issues became visibly brown relative to control tissues. The accumulation of phenolics in plant tissues suggests that certain components from the fungus possessed elicitor activity. Elicitor activity on treated been cotyledons was quantified by measurement of accumulations of low molecular weight and condensed phenolics. Data quantifying elicitor activity with intact conifer seedling roots and conifer calli …


Utah State University Commencement, 1988 – Main Campus, Utah State University May 1988

Utah State University Commencement, 1988 – Main Campus, Utah State University

Commencement Programs

Ninety-Fifth Annual Commencement of Utah State University


The Distribution Of Utah Grasshopper Species (Order: Orthoptera) In Relation To The Distributions Of Community Types And Abiotic Factors, Catherine A. B. Gilbert May 1988

The Distribution Of Utah Grasshopper Species (Order: Orthoptera) In Relation To The Distributions Of Community Types And Abiotic Factors, Catherine A. B. Gilbert

Biology

The practice of describing and mapping communities as community types assumes that all the organisms of a community have similar distributions. This assumption is counter to the hypothesis that organisms are distributed by their individualistic environmental tolerances and requirement (Gleason, 1926, 1939). Three major North American systems used to describe community-types are the biome (Clements and Shelford, 1939), the biotic area (Dice, 1943) and the life zone (sensu Holdridge, 1949). While these systems differ in the bases for community classification, they all use the distributions of 'key' species to predict the distributions of the remaining species in a community. …


Control And Evaluation Of Big Game Browsing Damage To Commercial Fruit Orchards, William E. Stone May 1988

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 May 1988

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 …


The Feasibility Of River Otter Reintroduction In Northern Utah, Joel P. Bich May 1988

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 …


The Role Of Homeostatic Imbalance In The Reported Immunomodulation Of T-2 Toxin, Michael Jay Taylor May 1988

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 …


The Bioavailability Of Iron From Meat, Spinach, Soy Protein Isolate, Meat:Spinach And Meat:Spi Mixtures Fed To Anemic And Healthy Rats, Dejia Zhang May 1988

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 …


Maternal Iron Parameters And Diet: Influence On Infant Iron Parameters And Development, Janet Bradshaw Anderson May 1988

Maternal Iron Parameters And Diet: Influence On Infant Iron Parameters And Development, Janet Bradshaw Anderson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to determine and evaluate the dietary intake of pregnant women living in this geographical area, evaluate how their diets related to their iron status, how their nutrient intakes compared with other studies, and how their iron status and diet affected infant iron status and development, as assessed by the Bayley Scale of Infant Development.

The study involved 32 pregnant women who were between 8 to 14 weeks gestation and 20 to 35 years of age. They were followed through pregnancy and their infants were followed until three months of age.

Three-day dietary records, a …


The Highest Local Density Of Reinforcement Controls Overall Post-Reinforcement Pause Duration On Ratio Schedules, Elliott J. Bonem May 1988

The Highest Local Density Of Reinforcement Controls Overall Post-Reinforcement Pause Duration On Ratio Schedules, Elliott J. Bonem

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A series of experiments were conducted with pigeons to investigate the variables responsible for differential postreinforcement pause (PRP) durations found on ratio schedules. In Experiment I, behavior on fixed-ratio (FR) and variable-ratio (VR) schedules were compared to behavior evoked by two interpolated schedules. The addition of a single FR 1 component to the FR 50 baseline schedule reduced the overall PRP to a duration comparable to that found on the VR 50 schedule. The addition of both an FR 1 and an FR 215 component to an FR 50 baseline reduced PRP and IRT durations below those on a VR …


The Effects Of Reinforcement Magnitude And Temporal Contingencies On Pre-Ratio Pause Duration, Marilyn K. Bonem May 1988

The Effects Of Reinforcement Magnitude And Temporal Contingencies On Pre-Ratio Pause Duration, Marilyn K. Bonem

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The present study was conducted to determine whether conjugate magnitude and temporal contingencies were effective in increasing the pre-ratio pause (PRP) duration and to determine the controlling variables that govern such contingencies. It has been reported in the literature that magnitude of reinforcement, if presented contingently, is effective in controlling performance and that inserting intervals of blackout (BO), during which responding does not lead to reinforcement, virtually always leads to control of responding, even though it has not been presented contingently. The conjugate schedules experimentally arranged reinforcement such that the longer the PRP, the longer was the duration of access …


The Correlation Between Life Satisfaction And Farm Involvement Among Utah Dairy Farm Men And Women, Phillip S. Browning May 1988

The Correlation Between Life Satisfaction And Farm Involvement Among Utah Dairy Farm Men And Women, Phillip S. Browning

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study is to look at the relationship between life satisfaction and farm involvement among dairy farm men and women in Utah. Farm involvement is defined as farm tasks, decision making, and participation in farm organizations. A sample of 116 couples were drawn from five counties in Utah. The husbands and wives were each interviewed separately. The sample is representative of the dairy farms in these five counties. However, the results of this study cannot be generalized to other types of farms in Utah or dairy farms from other locations.

The correlation between life satisfaction and farm …


The Immunological And Neurochemical Toxicity Of Benzene And Its Interaction With Toluene In Mice, Gin-Chang Hsieh May 1988

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 …


Big Game Depredation To Crops And Orchards In Seven Counties Of Northern And Central Utah: A Case Study, Kerry C. Mcbride May 1988

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 …


Interactions Of Vanadium Compounds With Reducing Equivalents: Evidence Of Free Radical Involvement And Possible Mechanisms Of Toxicity, Randal J. Keller May 1988

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 …


Studies On Encephalomyocarditis Virus-Induced Diabetes In Mice, John Henry Huffman May 1988

Studies On Encephalomyocarditis Virus-Induced Diabetes In Mice, John Henry Huffman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The D-variant of encephalomyocarditis (EMC-D) virus was given to SJL/J mice by the artificial, intraperitoneal (ip) route of infection, or by the natural routes of infection per os (po) or intranasal (i.n.), in comparable concentrations. The po route of infection was found to be ineffective. Mice given virus by either the ip or i.n. routes of infection became diabetic. Mice were more resistant to the infectious and diabetogenic properties of the virus when given by the i.n. than when given by the ip route. Glycosuria in mice given virus i.n. usually lagged one day behind that in mice given virus …


Luteinizing Hormone An Progesterone Response To Gnrh Administration At Insemination In Repeat-Breeder Holstein Cows, Robert Joseph Callan May 1988

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 …


Intracellular Water Distribution And Aging As Examined By X-Ray Microanalysis, Thomas Von Zglinicki May 1988

Intracellular Water Distribution And Aging As Examined By X-Ray Microanalysis, Thomas Von Zglinicki

Scanning Microscopy

The results reviewed here demonstrate that 1. the distribution of dry mass as observed in frozen-dried cryosections might be used as an unbiased measure of intracellular dry mass resp. water distributions in the tissue in vivo and 2. the well-known loss of water from cells during aging is solely due to a water loss from mitochondria without changes in the water content of all other components of the cell in the case of rat liver and heart muscle.

The reason for the water loss might be increased counter ion binding by membrane-bound enzymes due to decreased fluidity of the inner …


Characterization Of Chemical And Radiation-Induced Dna Damage In The Mdbk Cell Culture System, Jeffrey R. Hincks May 1988

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 …


Characterization Of Esterases And Glutathione S-Transferases In A Solitary Bee, Megachile Rotundata (Fab.): Variability, Developmental Multiplicity, Substrate Specificity, And Inhibition, Donald R. Frohlich May 1988

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 …


Occurrence Of Vesicular-Arbuscular Mycorrhizae In Degraded Rangelands And Physiological Responses Of Six Agropyron Cultivars To Infection, Di Jian Jun May 1988

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 …


Fire Frequency And The Vegetal Mosaic Of The Utah State University Experimental Forest, Linda L. Wadleigh-Anhold May 1988

Fire Frequency And The Vegetal Mosaic Of The Utah State University Experimental Forest, Linda L. Wadleigh-Anhold

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A fire history study conducted for the Utah State University (USU) Experimental Forest using three distinct periods of fire frequency, historic (1700-1855), settlement (1856-1909), and suppression (1910-present), showed a decreased mean fire interval (MFI) during the settlement period and a greatly increased MFI during the suppression era. The difference was attributed to the influx of ignition sources during the settlement of the nearby Cache Valley, located 40 kilometers to the west. The interaction of settlers with the resource during logging and livestock grazing activities encouraged the high MFI and created the vegetal mosaic now observed on the study area.

The …


An Experimental Analysis Of The Two-String Problem, Mary Ann Henneman May 1988

An Experimental Analysis Of The Two-String Problem, Mary Ann Henneman

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

The two-string problem (Maier, 1931) was used in an analysis of the contribution of experience in problem solving. In the two string problem subjects are shown two strings hanging from the ceiling and are instructed to tie the strings together. The strings are placed apart so that subjects are unable to grasp both strings simultaneously. The solution involves the use of items which are available in the vicinity of the strings. For example, a hammer can be used as a weight to make one string swing. The research comprised three separate experiments. The objective was to investigate environmental contributions, as …


Woman's Exponent: Cradle Of Literary Culture Among Early Mormon Women, Alfene Page May 1988

Woman's Exponent: Cradle Of Literary Culture Among Early Mormon Women, Alfene Page

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this paper was to define and discuss the early Mormon women's newspaper, Woman's Exponent, and its editors in developing a literary culture among Mormon women. Woman's Exponent served as the primary source of research to show through its literature that the women of Utah were encouraged to express themselves freely, and present their way of life to a world that held a grossly distorted view of them. The Exponent provided the forum for skilled writers to polish their craft, and new writers to develop their talents. The literary influence of the Exponent encouraged the women writers …


Gambel Oak For Spanish Goats: A Digestion-Balance Evaluation Of Nutrient Availability, Brian L. Dick May 1988

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 …


Acquisition Of Forgaging Skills By Lambs Eating Grass Or Shrub, Enrique R. Flores May 1988

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. …