Digital Commons Network^™

Is Rainbow Trout Condition Influenced By Invertebrate-Drift Density?, Randall B. Filbert

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Users of the Instream Flow Incremental Methodology CTFIM) commonly assume that there is a positive linear relationship between available habitat (WUA) and stream fish biomass. However, several studies have shown a lack cf correlation between WUA and biomass. Such poor relationships may occur if other factors limit fish abundance. Food availability is a potentially important factor limiting abundance of stream fishes and can affect blomass by influencing fish condition (individual weight). I collected rainbow trout (Oncorhynchus mykiss) exposed to different levels of invertebrate-drift density to determine if condition was greater where food was more abundant. I also examined …

Changes In The Vulvular And Vestibular Tissue Of The Bovine During The Estrous Cycle As Determined By The Use Of Near Infrared Interactance, Robert Alan Kunzler

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Near infrared reflectance spectroscopy is routinely used for the analysis of quality components of feedstuffs. Near infrared spectrophotometers, coupled with a fiber optic probe, could enable direct measurements of the live animal. This study was conducted to characterize changes in the vulva and vestibule during the bovine estrous cycle using near infrared (NI) spectroscopy. Sixteen cycling Holstein cows were observed for estrus twice daily from 40 days postpartum for three estrous cycles or until conception was verified. In addition, weekly rectal palpations, cowside milk progesterone tests, and tailhead chalk were used to aid in estrous detection. Near infrared spectra of …

Enzyme-Hydrolyzed Retentate For The Development Of A Whipped Topping Mix, Shirley Ann Bond

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Ultrafiltered skim milk concentrated to 20-22% solids was hydrolyzed with a mixture of proteases from Aspergillus oryzae and an acid protease from Aspergillus niger. The enzyme preparation from A. oryzae did not produce bitterness, so the effects of its hydrolyzing action on the whipping properties of the retentate in liquid and powdered forms were examined. Its effect on the amount of soluble nitrogen in the powder was also determined. After inoculation of 250 ml retentate with .05% w/v enzyme, the samples were held in a 45°C water bath. The samples thickened with increasing hydrolysis until syneresis occurred. They also …

Meat Effects On Nonheme Iron Absorption, Yunji Kim

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Studies were undertaken to investigate if gastric acidity and iron chelation to a meat component enhance nonheme iron absorption. Cereal meals, with and without added proteins, were gavaged into iron-deficient rats. The role of iron chelation was investigated by adding sodium phytate, an iron chelator implicated with decreased iron absorption, to the meals. The role of gastric acidity was investigated by treating the rats with cimetidine, which inhibits gastric acid production. In rats with normal acid production, beef, pork and chicken enhanced iron absorption when phytate had been added to the meals, suggesting a role for chelation in meat enhancement …

An Automated Reflectance Color Meter Instrument For Microbiological And Enzymic Assays, Tsz-Ching Yuan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The development of an automated instrument employing reflectance colorimetry was described. Several models were designed, assembled, and programmed to perform microbial and enzymic tests automatically. Samples were prepared manually or automatically by a Zymate™ II robot. These samples were incubated during the tests to maintain an optimum temperature for reactions and microbial growth. During incubation, color changes of appropriate indicator dyes in the sample/reagent mixtures were measured intermittently, recorded, and compared to previously defined end points. The computer-controlled instrument received data that related time of color changes with the initial numbers of microorganisms or the enzyme activity of the samples. …

The Effects Of Policy Development And Organizational Structure On The Performance Of Range Livestock Development Projects In Africa, Gregory Karl Perrier

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Range professionals are frequently involved in the arrangement of range development projects, both domestically and internationally. The success record of such projects has been uneven, particularly for projects in developing nations. The objective of this study was to provide range specialists a better understanding of potential management obstacles and barriers to success. This is accomplished through an examination of the management of three AID-funded pastoral development projects in Africa: the Tanzanian Masai Livestock and Range Management Project, the Somali Central Rangelands Development Project, and the Lesotho Lard Conservation and Range Development Project.

The study examined the effects of two important …

Evaluation Of Antiviral Compounds Against Avian Influenza, Evan W. Call

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Tests in vitro for antiviral activity against avian influenza viruses, A/Turkey/Sanpete/85 (H6N8) and A/Turkey/Sanpete/86 (H10N9), isolated in Sanpete County, Utah, utilized known antiviral agents, amantadine⋅HCl (adamantanamine hydrochloride) and ribavirin (1-β-D ribofuranosyl-1,2,4-triazole-3-carboxamide). The testing involved evaluation of seven drug concentrations. Maximum tolerated dose, minimum inhibitory concentration and therapeutic indexes were determined for each drug used. Both drugs demonstrated reasonable antiviral activity. Then they were tested against the H10N9 strain in 10-day-old Broad White turkey poults. Large- and small-particle aerosol delivery systems were the delivery methods utilized. Various parameters, including water and feed consumption, health score (based on visible signs), recoverable lung …

Factors Affecting Seeds In A Sagebrush-Steppe Ecosystem And Implications For The Dispersion Of An Annual Plant Species, Cheatgrass (Bromus Tectorum L.), Michael Ira Kelrick

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I investigated how shrub-induced spatial heterogeneity influenced and was manifested by a representative ground-story plant species at a sagebrush-steppe site in southwestern Wyoming. The dispersion of cheatgrass (Bromus tectorum) reflected differences between undershrub (higher plant densities) and interspace (between shrubs, supporting lower densities) microenvironments, hence the population ecology of this annual species served as a biological probe of shrub-associated patch structure in this community. Since cheatgrass is an annual, factors affecting the seed portion of its life cycle were of special interest. First, attributes of the above- and below-ground seed pool were characterized. The environment-wide seed depositional pattern …

Reproductive Strategies Of Northern Goshawks And Cooper's Hawks In North-Central New Mexico, Patricia L. Kennedy

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I assumed that the reproductive strategies of the two Accipiter species investigated in this study, the northern Goshawk (A. gentilis) and the Cooper's hawk (A. cooperii), would be similar to the strategies of other monogamous raptors with sex role partitioning. Any differences in the species' reproductive strategies, particularly hunting strategies, were expected to be a function of their size differences. Contrary to predictions, results indicated that, in north-central New Mexico during brood rearing, both species had similar hunting strategies and utilized similar prey species. These results also indicated that the reproductive strategies of the Cooper's hawk …

Potassium And Sodium Interrelations In Alfalfa Phenotypes Grown On Calcareous Soil, Suresh S. Dhumal

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Three greenhouse experiments were conducted with three phenotypes of alfalfa (Medicago sativa L.) obtained from a potassium (K)-deficient field and with their diallel crosses grown on low K soil. The first experiment was conducted to study the partitioning and broad-sense heritability of K and sodium (Na) between leaves and stems of the three phenotypes which were deficient in K and exhibited normal (N), marginal chlorotic (M), and white spot chlorotic (W) leaflets. The second experiment was conducted to study the partitioning of K and Na in leaves, stems, and roots as influenced by 32 alfalfa crosses obtained from diallel …

Rapid Determination Of Milk Components And Detection Of Adulteration Using Fourier Transform Infrared Technology, Ivan Von Mendenhall

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Absorption bands responding to changes in fat, protein, and lactose concentrations in milk were determined. The effects of milk fat variation and lipolysis on the infrared spectrum were studied.

Absorbances from 1283 to 1100 cm^-1 correlated with fat, protein, and lactose concentration and showed a low response to milk fat variation and lipolysis. A Fourier transform infrared spectrometer equipped with an attenuated total internal reflectance cell was calibrated using these absorption band s, partial least squares statistics, and milk samples from herds in Minnesota. When the fat, protein, and lactose concentrations in these samples were predicted, the standard deviations …

Hazard Perception And Preparation By Cross-Country Skiers In Utah, Kevin J. Kobe

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis examined how cross-country skiers perceive and prepare for winter hazards. A self-completion questionnaire was administered to cross-country skiers in northern Utah. The questions on the questionnaire were designed to explore the relationships that affect how skiers perceive and prepare for winter hazards. Additionally, the situation where skiers put themselves at risk due to lack of information as opposed to skiers placing themselves at risk through the desire to confront nature's dangers was explored. Variables that were contained in these relationships were correlated and the degree of correlation was measured.

Those that sought information on the day surveyed were …

Photosynthetic Capacity, Leaf Size And Plant Height In Wheat (Triticum Aestivum L.), Deborah L. Bishop

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Plant breeders often examine leaf size, plant height and photosynthetic capacity in an effort to increase wheat yield. This study was concerned with the relationship between these parameters in dwarf and semidwarf wheat cultivars (Triticum aestivum L.) with a wide range in flag leaf size. Photosynthetic capacity was measured at anthesis using photosynthesis versus intercellular CO2 response curves to determine maximum photosynthetic rate and ribulose-1,5- bisphosphate carboxylase efficiency. Leaf area, chlorophyll concentration, stomatal density, interveinal distance and dry mass partitioning were also examined. Smaller flag leaves had greater carboxylation efficiency and closer vein spacing. Dwarf wheat had higher chlorophyll …

Determining The Validity Of Methods Used In Meat Iron Analysis, Padmashri Ummadi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The validity of the Homsey method for heme iron, modified Schricker and sodium pyrophosphate extraction methods for nonheme iron and atomic absorption spectrophotometry (AAS) and ferrozine methods for total iron were determined using spikes of hemoglobin, ground beef baked to different degrees of doneness, proportional beef liver:catfish mixtures and National Institute of Science and Technology reference materials.

The mean spike recoveries of 0.01g and 0.02g Hb in raw beef and raw chicken samples were 96.7% of the heme iron for the Homsey method, 97.9% of the total iron for the ferrozine method, and 85.7% of the total iron for the …

Biological Detoxification Of Mercury Contaminated Soil, Shiying Zhang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study examined biological mercury removal from soil using mercury-resistant bacteria in soil microcosms. Mercuric chloride was used to artificially contaminate Kidman soil to mercury concentrations of 5 ppm and 10 ppm. Soil moisture content was maintained at three levels, 20%, 30% and 50%. Mercury resistant-bacteria were added to soil samples and the mercury removal rate was compared to control samples without added bacteria. Mercury removal rate was initially enhanced by the addition of bacteria. After 30 days, no difference was observed between samples and controls with initial mercury concentration of 5 ppm when soil moisture content was 20%. At …

Factors Affecting Moisture Distribution In 290-Kilogram Stirred-Curd Cheddar Cheese Blocks, Robert S. Reinbold

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this dissertation was to study factors affecting moisture distribution in 290-kilogram stirred-curd Cheddar cheese blocks cooled in stainless steel hoops. Uneven moisture distribution within blocks may create cheese with variable texture and flavor, which can be extremely costly to the producer. The effects of temperature, pH, and vacuum treatment on moisture distribution were investigated. Temperature, pH, moisture, and pressure profiles were presented. Also, comparisons were made between temperature profiles of 290- kilogram stirred-curd Cheddar cheese blocks cooled in stainless steel and in plywood hoops, as well as between temperature profiles of 66-kilogram Swiss cheese blocks cooled in …

Survival Of Lactobacillus Acidophilus And Bifidobacteria Bifidum In Ice Cream For Use As A Probiotic Food, Sharareh Hekmat

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Ice cream mix (12% fat, 11% milk solids nonfat, 12.5% sugar, and 4.5% corn syrup solids) was fermented with Lactobacillus acidophilus and Bifidobacterium bifidum. Half of the mix was heat treated at 82°C for 30 minutes and cooled to 40-41°C. The other half was warmed to 40-41°C and inoculated with the starter cultures. Both were made into ice cream and stored at -29°C. Survival of L. acidophilus and B. bifidum and of ẞ-galactosidase activity were monitored during 17 weeks of frozen storage. Reinforced clostridial medium was used to enumerate culture bacteria. Colony counts, after fermentation, for both L. acidophilus …

Effects Of Heat Treatment Of Ultrafiltered Milk On Its Rennet Coagulation Time And On Whey Protein Denaturation, Bashir H. Yousif

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this research was to determine the effects of heating (including heating to ultra-high temperatures) homogenized ultrafiltered whole and skim milks on whey protein denaturation and milk's subsequent rennet coagulation properties: coagulation time, curd firmness, and microstructure.

Whole and skim milk samples were ultrafiltered using a spiral wound ultrafiltration membrane system. Samples were preheated to 72°C for 58 s, held for 8 s then heated to 72, 89, 106, 123, or 140°C for more than 97 sand held for 4 s. The milk was then cooled to 60°C and homogenized, further cooled to 30°C, packaged into 120 ml …

Identification Of Potential Adhesins Shared Among Isolates Of Actinobacillus Species And Actinobacillus-Like Bacteria Cultured From Ram Lambs With Clinical Epididymitis, Yu-Wen Liu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Ram lamb epididymitis, a serious reproductive disease of sheep, is caused principally by bacteria belonging to the genera Haemophilus and Actinobacillus. Six bacteria were studied: the American Type Culture Collection (ATCC) of Actinobacillus seminis (ATCC 15768), ATCC of Actinobacillus actinomycetemcomitans (ATCC 29522), field isolates of A seminis (86722 and 4101) and field isolates of Actin obacillus- like bacteria (Y136 and D107). The objectives of this study were to quantitate the adhesion of these 6 bacteria to bovine kidney epithelial cells (BKECs) and ram epididymal epithelial cells (REECs), evaluate the effect of rabbit polyclonal antibody prepared against ATCC 15768 …

Economic Strategies For White-Tailed Deer And Livestock Production On Central And South Texas Ranches, Will E. Cohen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Recently, hunting and associated recreation have become an important business for Texas landowners. Most ranchers want to realize maximum net return from their investments. This study's objectives were to develop white-tailed deer (Odocoileus virginianus) and livestock enterprise budgets and to determine optimal economic combinations and levels of deer and livestock enterprises to maximize net returns. Questionnaires were mailed to landowners in the Edwards Plateau and South Texas Plains who purchased shooting preserve licenses in 1985. Five hundred and twenty-four ranchers responded (23.4%). Respondents were segregated by enterprises (deer, cattle, sheep, and Angora and Spanish goats) and a 5% …

Amelioration Effects Of Calcium Amendments On The Growth Of Phaseolus Vulgaris L. Under Sodium Stress, Salam Mahmoud Awada

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Two greenhouse experiments were conducted to determine the amelioration effect of Ca salts (CaS04 and CaC12) on the growth of snapbeans (Phaseolus vulgaris L.) under sodium stress and to determine the effect of ion speciation on the uptake of Ca, Na, S04, and Cl by snapbeans.

In Experiment 1, the seeds were grown in styrofoam pots, with a growing medium of sand and vermiculite at a volume ratio of 3:1. The treatment solutions were 0 (Hoagland's solution), 20, 40, 60, and 80 mmol_c/L NaCl or Na₂S0₄.

Statistical analysis (ANOVA) showed that NaCl treatments …

Hydrogen Uptake Genes And Nitrogen Fixation Efficiency Of Rhizobium Species In Symbiosis With Alfalfa, Chickpea And Pigeonpea, G. Mustafa Sajid

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The plasmids pDN211 and pDNll, isolated from the gene bank of the Rhizobium japonicum strain I-110, have been reported to complement two different Nif⁺ Hup^· (nitrogen fixation positive and hydrogen uptake negative) mutants. A 5.9-kb Hindiii DNA fragment of the cosmid pHU52, isolated from the gene bank of R. japonicum strain 122DES, has been reported to code for the two polypeptide subunits of uptake hydrogenase. To determine homology between the structural genes of uptake hydrogenase of the two strains, a Southern blot of the Hindiii restriction fragments of the plasmids pDN211 and pDN11 was hybridized to the 5.9-kb …

The Effects Of Calcium On The Response Of Snapbean To Sodium-Induced Stress, Masud Ahmad Khan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Soil salinity is a major concern to agriculture in arid and semiarid regions, where evapotranspiration causes salts originating from irrigation water (or sometimes naturally from the soil) to become concentrated in the rooting zone. In some areas, with good management, it has been economically feasible to ameliorate a sodic soil with Ca. The objective of this study was to investigate the effects of Ca amelioration of salinity (sodicity) on biomass, number of nodules, number of pods, weight of pods, ion uptake, and photosynthesis of Phaseolus vulgaris L.

Plants were grown in one liter styrofoam pots under greenhouse conditions. In the …

Development And Evaluation Of An Expert System For Use As An Aid In Culling Dairy Cattle, Max L. Checketts

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

An expert system for identifying cows to be culled, MAXCULL, was programmed to run on an IBM or compatible personal computer. It was designed to be used with Dairy Herd Improvement (DHI) records as an aid in decision making. MAXCULL used fifty-two health, seventeen reproduction, and thirty-nine production rules in the analysis.

MAXCULL was initially developed using two expert system tools. VP-Expert and Super Expert both had inductive abilities and were reasonably priced. VP-Expert was selected to continue the development of the MAXCULL system. The program used a rule-based method of storing knowledge, which was obtained from literature reviewed in …

Winter Habitat Selection Of Cutthroat Trout (Oncorhynchus Clarki) In A Large Regulated River, Ronald A. Englund

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Microhabitat use by cutthroat trout and macrohabitat use by both cutthroat and rainbow trout were studied i n the Green River below Flaming Gorge Dam during the winters of 1988 and 1989. Microhabitat parameters used by cutthroat trout, such as focal velocity, depth, and fish elevation, differed significantly in eddies, runs, and riffles. Mean focal velocities in runs were 0.79 body lengths/seconds (bl/s), in riffles 0.66 bl/s, and in eddies 0.24 bl/s. Cutthroat trout size also varied significantly with macrohabitat; larger fish were found in riffles.

Macrohabitat use by cutthroat trout and rainbow trout differed significantly among species, macrohabitat types, …

Mathematical Programming Applications In Agroforestry Planning, Laurence H. Reeves

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Agroforestry as a sustainable production system has been recognized as a land use system with the potential to slow encroachment of agriculture onto forested lands in developing countries. However, the acceptance of nontraditional agroforestry systems has been hampered in some areas due to the risk-averse nature of rural agriculturalists. By explicitly recognizing risk in agroforestry planning, a wider acceptance of agroforestry is possible. This thesis consists of a collection of three papers that explore the potential of modern stock portfolio theory to reduce financial risk in agroforestry planning.

The first paper presents a theoretical framework that incorporates modern stock portfolio …