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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
141

Utilization of wet brewers grains as a replacement for corn silage in lactating dairy cow diets

Mahnken, Christa Lynn January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / Micheal J. Brouk / An evaluation of short-term replacement of corn silage (CS) and soybean meal with a blend of wet brewers grains (BG) and cracked corn on milk production and DMI was completed utilizing 8 primiparous (192 DIM) and 4 multiparous (191 DIM) mid-lactation Holstein cows. Milk production, composition, DMI, production efficiency, fatty acid composition and diet digestibility were evaluated. Cows were allotted to a 4 x 4 Latin Square with 3 replications blocked by parity, DIM and energy corrected milk (ECM). Crude protein and starch levels were balanced between diets by varying the levels of cracked corn and soybean meal in four diets; 0 BG (0% wet BG and 24% CS of diet DM), 12 BG (12% wet BG and 12% CS), 18 BG (18% wet BG and 6% CS), and 24 BG (24% wet BG and 0% CS). Fifteen day periods were used, d11-15 designated for collection. Orts were collected daily and TMRs were fed at 5 to 10% of previous day’s intake. Cows were milked 3x/day and individual milk weights recorded at every milking. Milk samples, body weights and BCS were taken -2 and -1d pre-trial to obtain baseline data and d14 and 15 of each period. During collection, samples of TMR and orts were taken d1, 3 and 5. Fecal grab samples were taken d12-15 at 8 hr intervals and advanced 2 hrs every 24 hr period to account for diurnal variation. Dry matter intake was similar (P=0.33) among treatments (20.3, 20.8, 20.9 and 21.2 kg/cow) for 0 BG, 12 BG, 18 BG AND 24 BG respectively, however CP intake of 24 BG tended to be greater (P=0.05) than 0 BG. NDF intake was lower for 0 BG compared to all other treatments and 24 BG was higher than 12 BG (P=0.0007). Dietary fat intake was different (P<0.001) across all treatments, increasing with greater BG inclusion. Inclusion of BG had no effect (P=0.37) on milk production (30.5, 31.5, 31.6 and 32.1 kg/cow), fat percent or amount, protein percent, SNF, lactose or SCC, but protein yield (P=0.04) was lower and MUN (P=0.05)tended to be lower with 0 BG compared to 18 BG and 24 BG. Efficiency of milk production did not differ (P=0.93) among treatments. Milk fatty acid profiles were different among treatments, with general increases of individual fatty acids as BG inclusion increased. No differences were found in DM, CP or ADF digestibility across treatments. Results suggest wet BG fed simultaneously with grass hay can be utilized as a short-term replacement for CS in mid-lactation dairy cow diets.
142

Use of corn- and sorghum-based distillers dried grains with solubles in diets for nursery and finishing pigs

Feoli, Carolina January 1900 (has links)
Doctor of Philosophy / Department of Animal Sciences and Industry / Joe D. Hancock / Twelve experiments were completed to evaluate corn- and sorghum-distillers dried grains with solubles (DDGS) in diets for nursery and finishing pigs. In Exp. 1, corn-DDGS had 223 kcal/kg greater DE than sorghum-DDGS (P<0.02). In Exp. 2, pigs fed a corn-soy control diet had greater ADG, nutrient digestibility, HCW, and dressing percentage (P<0.02) and lower iodine value (IV) of jowl fat (P<0.001) than pigs fed diets with 40% DDGS. High-energy DDGS supported lower ADG, ADFI, and digestibility of DM (P<0.06) than moderate-energy DDGS, and sorghum-DDGS resulted in lower IV than corn-DDGS (P<0.001). In Exp. 3 and 4, addition of sodium bicarbonate to adjust dietary pH and electrolyte balance did not improve growth performance in nursery or finishing pigs (P>0.16) and adding molasses to improve palatability decreased (P<0.05) G:F for finishing gilts. In Exp. 5 and 6, enzyme additions improved nutrient digestibility in nursery (P<0.04) and finishing (P<0.01) pigs fed diets with high inclusion of DDGS. In Exp. 7, expander processing improved (P<0.02) ADG, G:F, and digestibility of DM, N, GE, and cellulose compared with standard steam conditioning of diets for nursery pigs, with the greatest response in G:F for pigs fed sorghum-DDGS (DDGS source × conditioning; P<0.02). In Exp. 8 and 9, expander conditioning improved G:F and dressing percentage (P<0.007) and digestibility of DM, N, and GE compared with standard conditioning (P<0.02), with the greatest response in digestibility of DM for the DDGS diets (diet × conditioning, P<0.01). In Exp. 10, 11, and 12, increasing tallow from 0 to 5% in diets with 40% DDGS improved (P<0.05) G:F. Dressing percentage was improved with addition of tallow and palm oil (P<0.08), but IV become worse (linear, P<0.06) as tallow was increased in the diet. Adding coconut oil improved growth performance and carcass firmness in pigs fed diets with 40% DDGS (P<0.01). In conclusion, growth performance and nutrient digestibility decreased with addition of DDGS to diets for nursery and finishing pigs. However, adding enzymes partially restored nutrient digestibility; expander conditioning improved G:F, dressing percentage, and nutrient digestibility; and adding coconut oil to diets with 40% DDGS improved G:F and carcass firmness.
143

Utilization of dry distillers grains and charcoal as nitrogen fertilizer in corn

Shroyer, Kyle J. January 1900 (has links)
Master of Science / Department of Agronomy / Scott A. Staggenborg / With the increase in bio-energy production there is also an increase in by-products. Without proper disposal, these by-products might cause future economic and/or ecological problems. Land application has potential as a disposal and/or nutrient cycling method if these by-products have nutritive value for agricultural crops. The purpose of the study was to compare the use of two by-products of bio-energy production, dry distillers grains (ethanol) and charcoal(pyrolysis), as fertilizer with urea in corn (Zea mays L.). The experiment consisted of four location-years in Kansas. Treatments were dry distiller’s grains (DDG) no-till and tilled for four location-years and char no-till and tilled for three location-years. No-till urea was used as a baseline for comparison at all location-years. The Nitrogen rates ranged from 45 to 180 kg N ha-1. All source material was spring applied before tillage and planting. The corn yields for DDGs and urea were the almost the same across tillage treatments and locations. For DDG no-till, DDG tilled, and urea, the rates at which to achieve the same yields were 97, 111, 78 kg N ha-1, respectively. Corn yields for char at all rates and tillage treatments were the same as no fertilizer. The char, because of immobilization or lack of decomposition, did not contribute to the nitrogen needs of the corn. Neither material showed any inhibitory or otherwise negative effects on the corn in terms of grain yield compared with the control. But both DDGs and char had to have large amounts of material applied to achieve the same amount of nitrogen as urea. Land application of DDGs and char has potential merit for disposal/nitrogen cycling with DDGs being preferred for its nitrogen contribution.
144

Influence of dietary dried distillers grains and glycerol on bacon quality

Goehring, Brandon Lee January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / Terry A. Houser / The objectives of this study were to determine the impact of 0 and 20% dried distillers grains with soluble (DDGS) and increasing levels of glycerol (0, 2.5 and 5%) in grow-finishing rations on bacon quality and to determine the relationship between belly firmness and slicing yield for commercially produced bacon. A total of 84 barrows (PIC, initially 31.03 kg) were fed corn-soybean meal-based diets organized in a 2 x 3 factorial with primary effects of DDGS (0 or 20%) and glycerol (0, 2.5, or 5%) as fed. Belly length was measured from flank end to blade end. Belly thickness was measured at eight locations evenly spaced around the perimeter of the belly. Belly firmness was measured by centering bellies perpendicularly (skin side up and skin side down) over a stainless steel smokestick and measuring the flex between the edges on the ventral and dorsal edges of the belly. Bellies were injected at 12% of the skinned belly weight resulting in a final concentration of 1.74% salt, 0.5% sugar, 0.3% sodium phosphate, 120 ppm sodium nitrite, and 500 ppm sodium erythorbate in the bellies. Bellies were cooked to an internal temperature of 53oC, chilled, pressed and sliced for evaluation. Belly slice yield was calculated by determining the yield of #1 type bacon slices. Proximate analysis and fatty acid analysis were evaluated by taking every 10th bacon slice beginning from the caudal end to make a composite sample for each belly. Iodine value was calculated using the resulting fatty acid content results. Twenty bacon slices were removed from the belly one-third the length of the belly from the cranial end for sensory analysis and cooking yields. Sensory characteristics were evaluated on an 8-point scale for brittleness, bacon flavor intensity, saltiness and off-flavor. There were no significant DDGS x glycerol interactions on any parameters measured (P > 0.08). Inclusion of 20% DDGS in pig diets decreased belly firmness (P < 0.04) as measured by the belly flop fat side down method. Twenty percent DDGS decreased the percentage of myristic acid, palmitic acid, palmitoleic acid, stearic acid, oleic acid, vaccenic acid, total saturated fatty acids, and total monounsaturated fatty acids (P < 0.01). In contrast, 20% DDGS increased the percentage of linoleic acid, α-linolenic acid, eicosadienoic acid, total polyunsaturated fatty acids and decreased unsaturated: saturated fatty acid ratios, polyunsaturated: saturated fatty acid ratios, and iodine values (P < 0.01). Statistical correlation analysis of belly processing characteristics showed that by increasing belly weight there will be an increase in smokehouse yields (R = 0.81), increasing smokehouse yields will increase slice yield (R = 0.71), increasing belly thickness results in firmer bellies (R = 0.94) and increasing belly firmness will increase slice yields (R = 0.60). Fatty acid content did not correlate with any belly processing characteristic (R < 0.50). Iodine values were highly correlated with Total MUFA (R = 0.83) Total PUFA (R = 0.79), Total TFA (R = 0.75), and UFA: SFA ratio, and PUFA: SFA ratios (R = 0.83). The inclusion of 0, 2.5 and 5% glycerol in swine diets did not affect any measured parameters in this study. In conclusion, feeding DDGS at a level of 20% decreased belly firmness and changed the fatty acid profile; however, it did not affect belly processing or sensory characteristics. Glycerol fed at 2.5 or 5.0% did not affect belly quality, fatty acid profile, or sensory characteristics of bacon.
145

The effect of distiller's grains on the prevalence and concentration of Escherichia coli O157 in cattle

Jacob, Megan E. January 1900 (has links)
Doctor of Philosophy / Department of Diagnostic Medicine/Pathobiology / Tiruvoor G. Nagaraja / Escherichia coli O157 is a major foodborne pathogen that causes enteritis in humans ranging in severity from mild to bloody diarrhea to hemolytic uremic syndrome and even death. Cattle are asymptomatic carriers and fecal shedding of the organism is the major source of contamination of food and water for human infections. Distiller’s grains (DG) are ethanol fermentation co-products that are valuable feed ingredients for use in cattle diets. Previous research suggests an association between feeding DG and an increased fecal shedding of Escherichia coli O157:H7. The objectives of the research were to evaluate fecal E. coli O157:H7 prevalence and concentration in cattle fed diets with and without DG, determine if the association was dependent on inclusion level or form (wet or dried), evaluate the association in populations of cattle at harvest, and evaluate a potential intervention strategy. Our results indicated that cattle fed DG had a higher prevalence and shed a higher concentration of E. coli O157 than cattle fed diets without DG. The relationship was not dependent on the DG form, however, it was affected by the inclusion level of DG in the diet. Cattle that were fed 40% DG had a higher E. coli O157:H7 prevalence than cattle fed control or 20% DG diets and cattle fed 20% DG had a prevalence that was not statistically different from control cattle. The same response was observed in a subpopulation of cattle, termed super-shedders, which shed E. coli O157:H7 at higher concentrations than the general population. At harvest, we did not find differences in E. coli O157:H7 or super-shedder prevalence between cattle fed diets with or without DG, however, study design limitations affected the power of the study. Finally, previous work had shown that cattle fed dry-rolled grains had a decreased prevalence of E. coli O157:H7 when compared to cattle fed steam-flaked grains. We evaluated the effect of feeding DG and dry-rolled corn (DRC), alone or in combination, and observed no difference in E. coli O157 prevalence between cattle fed either DG or DRC diets. In conclusion, DG supplementation increased the prevalence and concentration of E. coli O157:H7 in cattle.
146

Fertilizing Small Grains in Arizona

Ottman, Michael, Thompson, Tom 03 1900 (has links)
6 pp. / Guidelines for nitrogen fertilization of small grains are presented using crop need, calendar dates, or tissue testing. Relationship between grain protein and nitrogen fertilization is presented. Phosphorus, potassium, and other nutrients are also discussed.
147

Grikių grūdų rūšiavimo oro sraute tyrimai / Research of buckwheat grain sorting in the air flow

Jonušis, Darius 02 June 2011 (has links)
Darbo apimtis 45 puslapiai, tame tarpe 31 paveikslas. Literatūros sąraše 51 šaltinis. Darbo pradžia 2009 09 01, pabaiga 2011 05 10. Tikslas. Ištirti grikių grūdų sklaidą nuožulniajame oro sraute. Literatūros apžvalgoje atlikta sėklų rūšiavimo būdų mokslinių tyrimų apžvalga. Atlikta grūdų valomųjų analizė bei teorinių tyrimų apžvalga. Laboratoriniais tyrimais nustatytos grikių grūdų aerodinaminės savybės ir drėgnis. Eksperimentiniais tyrimais nustatyta grikių grūdų sklaida nuožulniajame oro sraute, keičiant oro srauto greitį, kampą bei grikių grūdų srautą. Tyrimų rezultatais pagrįsta, kad grikių grūdus rūšiuojant nuožulniajame oro sraute, rekomenduojamas oro srauto greitis 10 m/s, oro srauto kampas 3 laipsniai ir grikių grūdų srautas 0,9 kg(m/s). Nustatant grikių grūdų rūšiavimo parametrus būtina atsižvelgti į dėžutėse subirusių 1000 grūdų masę. Tinkamai parinkus nuožulniojo oro srauto parametrus grikių grūdus galima rūšiuoti oro srautu. / This work consists of 45 pages, including 31 figures. There are 51 entries in the references. This work was started on the 1 st of September 2009 and it was finished on the 10th of May 2011. The object of the work. To investigate the dissemination of buckwheat grain at the bevelled air flow. The analysis studies of seed sorting techniques is made in the literature review. The research work review of grain cleaner and theoretical studies is also done. The critical speed and humidity of buckwheat grain is established by laboratory studies. Experimental studies have shown the buckwheat grain dissemination at the bevelled air flow, by changing the supply of buckwheat flow, air flow speed and angle. It was determined, that recommended buckwheat sorting at the bevelled air flow is the most effective at 10 m/s air flow rate of 0,9 kg(m/s) shall be filed in buckwheat grain flow and air flow 3 angle. In determining the screening parameters of buckwheat sorting, must be taken into account 1000 grain weight. Properly selected the parameters of beveled air flow, buckwheat can be sorting by the air flow.
148

An investigation into ecological farming systems on the Canadian Prairies

Dick, Calvin 13 September 2016 (has links)
There are currently numerous alternative food production models that may have potential to contribute substantially to improved environmental sustainability. However, such alternatives are not well studied, particularly within the context of the Canadian Prairies. To increase knowledge in this area, this thesis performed a preliminary agronomic trial for food grain production in intermediate wheatgrass (Thinopyrum intermedium), investigating the effects of legume intercropping and residue management. Mean grain yields were 520 and 447 kg/ha in 2014 and 2015, respectively, and a significant yield increase was observed following grazing with sheep. A series of farm case studies were also conducted in order to characterize ecological farming approaches on the Canadian prairies. The most consistent strategy among the farms was to increase diversity in multiple facets for both environmental and economic benefit, including more crop and livestock species, system and landscape components, and marketing strategies. / October 2016
149

Taille des grains et localisation de la déformation dans la lithosphère / Grain Size and localization of deformation in the lithosphere

Rozel, Antoine 25 June 2010 (has links)
Cette thèse a pour but d’étudier l’impact de la taille des grains sur la rhéologie du manteau terrestre. Nous avons proposé un nouveau modèle d’évolution de la taille des grains et montré que les états d’équilibre qu’il prévoit sont en adéquation avec les données expérimentales obtenues sur des échantillons d’olivine. Ce modèle est illustré par des simulations numériques d’une zone de cisaillement et de convection du manteau. Nous avons montré que notre formalisme favorise la localisation la déformation et modifie le régime de convection des planètes. Notre modèle propose que l’évolution d’une distribution de tailles de grains soit entièrement contrainte par l’énergie des joints de grains. Cette énergie diminue lors de la croissance normale et augmente lors de la recristallisation dynamique. Notre modèle stipule que l’énergie nécessaire à la nucléation des nouveaux grains est soustraite à l’énergie dissipée dans le matériau par les dislocations. Même lorsque les grains de taille moyenne sont en régime diffusif, les grains les plus gros se déforment en régime dislocatif, peuvent continuer à subir de la recristallisation et ainsi peuvent concourir à la réduction de la taille moyenne. Lorsque les effets de la croissance et de la nucléation se compensent, nous pouvons comparer l’état d’équilibre obtenu avec les données expérimentales. Nous montrons que le partitionnement de l’énergie fournie dépend principalement de la température. Ce modèle est ensuite testé dans une simulation numérique de zone de cisaillement. Dans ce système, selon la température, la contrainte déviatorique et la taille des grains, la déformation peut s’effectuer en régime de diffusion ou en régime de dislocation. Contrairement à nos attentes, notre modèle montre que la déformation se localise moins efficacement lorsque le cœur de la zone de cisaillement passe en régime de diffusion. La taille des grains semble favoriser l’apparition des zones de cisaillement en y baissant la viscosité mais ne semble pas localiser intrinsèquement la déformation. Finalement, nous avons testé notre équation de l’évolution de la taille des grains à l’aide de simulations numériques de convection du manteau. La température étant élevée dans le manteau, nous avons considéré que les grains étaient tous dans l’état d’équilibre prévu par notre modèle. Nous avons observé que la taille des grains peut suffire à modifier le régime de convection des planètes en créant une couche très non-Newtonienne dans leur lithosphère. Cette thèse a montré que la taille des grains influence fortement la dynamique des planètes en localisant la déformation à leur surface. Le nouveau modèle qu’elle propose apporte une vue nouvelle sur la création et l’entretien du régime de tectonique des plaques. / In this thesis, I studied the impact of grain size on the rheology of the mantle of the Earth. We propose a new model of grain size evolution and show that the equilibrium states it predicts are in good agreement with the experimental data obtained on olivine samples. This model is illustrated by numerical simulations of mantle convection and shear zones. I show that our formalism has a non-negligible effect on the localization of deformation in shear zones and strongly modifies the convection regimes of planets. In our formalism, we propose that the energy of a grain size distribution is fully constrained by the energy of the grain boundaries. This energy diminishes during grain growth and increases during dynamic recrystallization. Our model stipulates that the amount of energy required to nucleate new grains, which is a dislocation-assisted process, is substracted to the energy dissipated in the material. We also show that even when the mean grain size is located in the diffusion regime, the biggest grains of the distribution can remain in the dislocation regime and continue to nucleate smaller grains. Thus, the mean grain size can decrease, even in the diffusion regime. When the growth and recrystallization processes are equivalent, the grain size distribution reaches an equilibrium state which can be compared with experimental data (various published olivine piezometers). The experimental calibration of our model shows that the partitioning of energy is principally temperature-dependent. I test this new model in a fully viscous numerical simulation of shear zone with a non-Newtonian- grain size-dependent viscosity. In this system, depending on the temperature, grain size or thermal state, the deformation can locally operate in diffusion or dislocation regime. Paradoxally, my model shows that the deformation is more localized when the shear zone is in the dislocation regime, where the viscosity does not depend on grain size. We observe that the grain size parameter tends to favor the apparition of shear zones because it minors the stress field but is insufficient to localize deformation in the case of a constant plate velocity. A grain size-activated localization of deformation seems to require a time-dependent stimulation which is typically obtained in visco-elasto-plastic configurations. Finally, I have tested our grain size evolution model, in its static form, in a set of numerical simulations of mantle convection. Our model shows that the grain size reaches its equilibrium very quickly in sub-lithospheric conditions. Thus, I have considered that the grain size distribution is always in the equilibrium state predicted but our model. I show that the consideration of the grain size parameter can fully modify the convection regimes of telluric planets. When surface stresses are high enough to reach the diffusion regime, the stagnant lid usually obtained with very temperature-dependent viscosities is broken by a very non-Newtonian and grain size-dependent top layer. This thesis shows that grain size strongly influences the dynamics of planets in localizing the deformation in their surfaces. The model we propose brings a new view of the creation of plate tectonics at the surface of the Earth.
150

The effects of nutrition and reproductive strategies on performance of beef cattle grazing native shortgrass range in western Kansas

Bennett, Bradley Wayne January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / John Jaeger / Cattle grazing dormant native range (< 7% crude protein; CP) require supplementation of additional protein to sustain body weight (BW) and body condition score (BCS). Daily delivery of these supplements is an economic burden to cattle producers faced with challenging economic circumstances. Supplementing cows infrequently (as little as once/week) has produced equivalent BW and BCS changes compared to daily delivery. Dried distiller’s grains with solubles (DDGS) provides more ruminally-undegradable protein (RUP; 50-60%) compared to traditional oilseed-meal supplements (i.e. soybean meal) that are >50% ruminally-degradable protein (RDP). Therefore, our objective was to evaluate the effects of supplementation frequency on performance, reproductive success, eating behavior, and subsequent calf performance of spring-calving cows supplemented with DDGS. No differences in ending BW (P = 0.69) and BCS (P = 0.49), or changes in BW and BCS over the supplementation period (P = 0.82 and 0.70, respectively) were observed among cows supplemented every d, every 3 d, or every 6 d. Calf BW at birth, weaning weight (WW), and average daily gain (ADG) were similar among treatments (P = 0.19, 0.12, and 0.10, respectively). First-service conception rate (FSCR) and final pregnancy rate (PR) were also not affected by supplementation frequency (P = 0.62 and 0.76, respectively). The development of replacement heifers is a large expense for cow-calf producers. Improved breeding and heifer development strategies aimed at ensuring the success of replacement females have been developed but reproductive failure still remains a problem. The stress associated with breeding and handling procedures may decrease reproductive success. Therefore, the objective was to determine if intramuscular administration of flunixin meglumine (1.1 mg/kg BW) 14 days post-breeding would improve FSCR and PR in non-transported replacement heifers. Under the conditions of our study, flunixin meglumine did not improve (P = 0.87) first service conception rate above that of control heifers (41.2% and 42.3%, respectively). Final pregnancy rate also was not different between treatments and averaged 81.8% (P = 0.40).

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