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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.
321

Application of rumen-protected lysine to lower crude protein diets for lactating dairy cows

Pretz, Jon Patrick January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / Micheal J. Brouk / The study objective was to evaluate the application of supplemental rumen-protected lysine (RP Lys) to maintain milk production when reducing the crude protein levels in a lactating dairy cow diet. Twelve lactating multiparous Holstein cows, averaging 129 DIM, 50.2 kg milk yield, 3.6% fat and 2.9% true protein were randomly assigned to one of four 3x3 Latin squares. Each 14-d period had 11 d for adaptation followed by 3 d of data collection. Cows were offered one of three experimental treatment rations formulated with CPM Dairy (v3.0); Positive control (PC) — formulated to meet all nutrient requirements; Test diet (Test) — negative control diet formulated to meet nutrient requirements, except deficient in metabolizable protein (MP) (approximately 200 g/d) and first limiting in metabolizable Lys (approximately 10 g/d); and Test+RPL — same basal diet as negative control + RP-Lys to provide 14.5 g/d of MP-Lys. For Test+RPL, 45g of RP-Lys (AminoShure-L®; Balchem Corp., New Hampton, NY, containing 23.4g Lys) was top-dressed on the TMR once daily. The PC diet resulted in lower dry matter intake (P = 0.03) as compared to either the Test or Test+RPL diet. PC, Test, and Test+RPL cows averaged 42.6, 42.9, 43.6 kg/d of milk and 27.3, 28.4, 28.8 kg/d of DMI, respectively. Crude protein intake for the PC, Test, and Test+RPL diets was 4.83, 4.67, and 4.74 kg/d respectively. MUN decreased (P < 0.01) for cows on Test and Test+RPL diets as compared to PC diet (12.5, 12.5 and 14.9 mg/dL, respectively). Milk yield, milk components, milk component yields, FCM, ECM, SCM and production efficiencies (milk, ECM, SCM and FCM) did not differ (P > 0.05) among treatments. A post-study CPM Dairy evaluation using final chemical composition analyses of the feedstuffs and average production data from the animals predicted that diets supported more than 47 kg of milk and Lys was not limiting. Cows on the study produced slightly less milk, however DMI was 5-8% more than predicted by initial formulations. Formulation accuracy of the MP and Lys deficient diet may have been improved if data had been available from an initial adjustment period measuring DMI, body weight, milk yield and milk composition. It is also possible that the bioavailability of the RP Lys was not as great as thought during the diet formulation process. However, given the fact that the post-trial CPM analysis did not indicate a deficiency of Lys, it is not very likely that this impacted the results of this trial.
322

Detoxification and nutritional enhancement of soy meal via microbial bioprocessing

Chen, Liyan January 1900 (has links)
Doctor of Philosophy / Department of Grain Science and Industry / Praveen V. Vadlani / Soy meal (SM) is the main protein source for monogastric animals. Anti-nutritional factors in SM limited its usage for young monogastric animals. Aspergillus was investigated to degrade these factors and to enhance its nutritional value via solid state fermentation. Galacto-oligosaccharides were totally degraded from the initial 9.48 mmol/100 g, and trypsin inhibitor decreased from 10.7 TIU/mg to a non-detectable level after 36 hr fermentation. Structural polysaccharides decreased by 59% (w/w) and the degree of hydrolysis of SM protein increased from 0.9% to 7% (w/w) through the 7 d fermentation. Fermentation also modified nutritional factors. Protein content increased from 50.47% (w/w) to 58.93% (w/w) after 36 hr fermentation. Amino acid profile was significantly enhanced. Two - stage temperature-induced fermentation protocol was developed to increase the degradation rate of phytic acid by A. oryzae (ATCC 9362) and by A. ficuum (ATCC 66876). The first stage maximized phytase production with fermentation parameters obtained by central composite design. The second stage achieved maximum enzymatic degradation with parameters obtained by studying the phytase temperature characteristics. While using A. oryzae, 57% of phytic acid in SM was degraded by the two stage protocol compared to 39% degradation from single stage fermentation. For A. ficuum, the two-stage temperature fermentation protocol achieved a 98% degradation level of phytic acid degradation compared with the single stage process. Two-stage temperature-induced co-fermentation of A. oryzae and A. ficuum was investigated to simultaneously degrade phytic acid and soy protein with high efficiency. Co-fermentation of A. oryzae and A. ficuum resulted in higher phytic acid degradation than A. oryzae fermentation and superior protein hydrolysis compared to A. ficuum fermentation. Sterilization distorted the results of fermentation effect on soy allergens and soy protein degradation. Virginiamycin is a kind of bacterisin. It was added to A. oryzae solid state fermentation, to exclude the necessity of SM sterilization. Nonsterile, solid state fermentation using A. oryzae and virginiamycin showed the complete degradation of α and α’ subunits of β-conglycinin and decreased immunoreactivity of soy protein. The modified SM after microbial bioprocessing created an innovative product with enhanced characteristics with potential wider applications for feed industry.
323

Integrated weed management in Kansas winter wheat

Refsell, Dawn E. January 1900 (has links)
Doctor of Philosophy / Department of Agronomy / J. Anita Dille / Integrated weed management (IWM) is an ecological approach to weed control that reduces dependence on herbicides through understanding of weed biology and involves using multiple weed control measures including cultural, chemical, mechanical and biological methods. The critical period of weed control is the duration of the crop life cycle in which it must be kept weed-free to prevent yield loss from weed interference. Eight experiments were conducted throughout Kansas between October 2010 and June 2012 to identify this period in winter wheat grown under dryland and irrigated conditions. Impact of henbit and downy brome density on winter wheat yields were evaluated on four farmer’s fields with natural populations and on a research station with overseeded populations. Henbit density up to 156 plants m-2 did not affect winter wheat yield, while downy brome at a density of 40 plants m-2 reduced yield by 33 and 13% in 2011 and 2012, respectively. In the presence of downy brome, winter wheat should be kept weed-free approximately 30 to 45 days after planting to prevent yield loss; otherwise, weeds need to be removed immediately following release from winter dormancy to prevent yield loss due to existing weed populations. Flumioxazin and pyroxasulfone are herbicides registered for use in winter wheat, soybean and corn for control of broadleaf and grass weeds. Flumioxazin and pyroxasulfone were evaluated for plant response to localized herbicide exposure to roots, shoots, or both roots and shoots utilizing a novel technique. Two weed species, ivyleaf morningglory and shattercane, as well as two crops, wheat and soybean, were evaluated for injury after localized exposures. The location and expression of symptoms from the flumioxazin and pyroxasulfone herbicides were determined to be the shoot of seedling plants. The utilization of preemergence herbicides in winter wheat is not a common practice, although application may protect winter wheat from early season yield losses as determined by the critical weed-free period. Kansas wheat growers should evaluate the presence and density of weed species to determine which weed management strategy is most advantageous to preserving winter wheat yield.
324

Investigations on power consumption, pelleting temperature, pellet quality, and sugar yield in pelleting of cellulosic biomass

Zhang, Qi January 1900 (has links)
Doctor of Philosophy / Department of Industrial and Manufacturing Systems Engineering / Zhijian Pei / Donghai Wang / The U.S. economy has been depending on petroleum-based liquid transportation fuels (such as gasoline, diesel, and jet fuels). Currently, about 50% of petroleum used in the U.S. is imported. Petroleum is a finite and non-renewable energy source and its use emits greenhouse gases. Therefore, it is extremely important to develop domestic sustainable alternatives for petroleum-based liquid transportation fuels. Ethanol produced from cellulosic biomass can be such an alternative. However, several technical barriers have hindered large-scale, cost-effective manufacturing of cellulosic ethanol. One such barrier is related to the low density of cellulosic feedstocks, causing high cost in their transportation and storage. Another barrier is low efficiency in conversion of cellulose to fermentable sugar (pretreatment and enzymatic hydrolysis are two major conversion processes), causing high cost in pretreatment and enzymatic hydrolysis of cellulosic biomass. Ultrasonic vibration-assisted (UV-A) pelleting increases both density and sugar yield of cellulosic feedstocks. Incorporating UV-A pelleting into cellulosic ethanol manufacturing may help realize cost-effective manufacturing of cellulosic ethanol. This PhD dissertation consists of 13 chapters. An introduction is given in Chapter 1. Chapter 2 presents a literature review on related topics. Experimental studies regarding effects of input parameters (such as particle size, pressure, and ultrasonic power) on output parameters (density, durability, stability, and sugar yield) are presented in Chapters 3–4. In Chapters 5–6, comparisons are made between UV-A pelleting and ring-die pelleting (a traditional pelleting method) in terms of pellet properties (density and durability), power consumption, and sugar yield under different conditions. Next, effects of input parameters (such as biomass type, particle size, moisture content, pelleting pressure, and ultrasonic power) on power consumption are studied in Chapters 7–9. Chapter 10 presents an investigation on biomass temperature in UV-A pelleting. Chapter 11 presents an investigation on effects of UV-A pelleting on sugar yield and chemical composition of cellulosic biomass. Chapter 12 presents an investigation on influence of UV-A pelleting on biomass characteristics (such as crystallinity index, thermal properties, and morphological structure). Finally, conclusions are presented in Chapter 13.
325

Phenotypic and genetic relationships among temperament, immune, and carcass traits in beef cattle

Bates, Kerri E. January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / Jennifer Minick-Bormann / Cattle temperament has historically influenced selection decisions due to ease of handling. However, temperament may also influence economically relevant traits. The purpose of this study was to investigate relationships between temperament, Bovine Respiratory Disease (BRD) incidence, and resulting carcass merit in feedlot steers. Across a two year period, 2,870 crossbred steers were shipped from a single ranch source to a feedlot. At the time of feedlot placement, as well as at the time of reimplantation, temperament was measured via chute score (CS) and exit velocity (EV). Blood samples were taken upon arrival to the feedlot to determine circulating concentrations of interleukin 8 (IL-8) and cortisol, both of which are involved in immune function. Performance traits, including weight and gains, were measured at feedlot placement (d 0), reimplantation (d 73-100), and again 59 to 70 days later. Recorded carcass data included HCW (HCW), USDA yield grade (YG), marbling score (MS), ribeye area, and lung scores. Phenotypic statistical analysis was performed with SAS statistical software (SAS Inst., Inc., Cary, NC) and genetic parameters were estimated using ASREML (Ver. 3.0, VSN International, Ltd., Hemel Hempstead, UK). The pedigree file included records of 7,177 animals with up to 7 generation of pedigree. Contemporary group (CG, n=11) included initial ranch unit, date of arrival to the feedlot, feedlot pen, and processing dates. Fixed effects included in the model were pre-feedlot entry BRD treatment and CG. Cattle with higher CS at placement subsequently had more BRD incidence (P < 0.01). There was a positive phenotypic correlation between placement CS and blood cortisol concentrations (r = 0.07; P< 0.01), and cattle with higher cortisol concentration contracted BRD more often than their calmer peers (P < 0.05). Circulating IL-8 concentration had no influence on feedlot health. At the time of reimplantation, cattle that had been treated for BRD in the feedlot had lower chute scores (P < 0.001). Heritability estimates for CS at placement, EV at placement, CS at reimplantation, and EV at reimplantation were 0.23, 0.17, 0.19, and 0.27, respectively. BRD incidence had a negative genetic correlation with all measures of temperament recorded at the second processing period.
326

Analysis of a cooperative dairy producer risk management program

Heiman, Travis January 1900 (has links)
Master of Agribusiness / Department of Agricultural Economics / Kevin Dhuyvetter / Dairy Farmers of America (DFA) is national milk marketing cooperative. DFA’s primary focus is to market the milk of the cooperative’s 17,000 members. In addition, DFA offers its membership a number of farm services. The sole purpose of these services is to make it easier for DFA members to operate their businesses. One of the services offered provides members access to forward contracting alternatives for pricing their milk. The objective of this research is to utilize demographic and other information related to the characteristics of individual dairy producers and determine how these characteristics impact the use (or lack thereof) of risk management marketing tools. More specifically, the focus of this research is to identify what types of dairy producers are most likely to use the DFA’s forward contracting program. The logit model estimated indicated that regional and demographic differences impact the use of DFA’s forward contracting program. Members in the Mountain Area are most likely to use the program followed by members in the Central Area. Demographic differences that significantly impacted the use of forward contracting include age (older producers use forward contracts less than younger operators) and the size of operation, as measured by milk produced per year (larger operators were more likely to use forward contracting services). While the estimated logit model did identify several factors related to the use of forward contracting services, relationships are not particularly strong and the percent of producers using the services is relatively low. Thus, the model is limited in its ability for identifying key factors and thus it will be difficult for DFA to base a targeted marketing effort at certain producers. DFA would need additional information about their members to successfully target for this farm service.
327

Competitive factors affecting the expansion of Greenfield elevator sites

Wisner, Michael January 1900 (has links)
Master of Agribusiness / Department of Agricultural Economics / Michael A. Boland / The purpose of this thesis is to identify Greenfield grain facility sites within 100 miles of Holdrege, Nebraska and to evaluate the feasibility of these sites. CHS Agri Service Center currently has facilities that are within 50 miles of Holdrege, Nebraska. However there are no Greenfield sites in this area that would be feasible due to a large number of competitors already operating in this area. This problem was broken down into two components. The first is site selection and the second is a financial model using net present value to determine if the sites selected would be profitable to the standards that CHS, Inc. requires (12% or better return on assets). In order to determine where Greenfield sites might be located supply and demand factors were evaluated to determine surplus and deficit grain areas. The areas where there were large surpluses of grain have the greatest potential for a Greenfield facility to succeed. Then a feasibility analysis of the chosen sites is conducted using net present value and internal rate of return analysis to determine if there is enough grain volume to operate the grain facility above the 12% return on assets criterion. After a detailed review of the supply and demand factors of grain in the region, two locations were determined to be good candidates for further study. Based on recent projects completed at CHS, Inc. two model facilities were created as tools to determine if a certain facility type is more profitable than another. The cost structures for these two model facilities are based on costs that are currently incurred at CHS Agri Service Center locations. It was found that neither facility at either location was profitable enough to meet the minimum performance criteria required by CHS, Inc. As a result of these findings it may be possible to move ahead with a Greenfield facility at one of these sites if a higher volume can be obtained. A merger with another grain company in the immediate area of the proposed facility may be the best way to increase volume.
328

Modified soy protein based adhesives and their physicochemical properties

Qi, Guangyan January 1900 (has links)
Doctor of Philosophy / Department of Grain Science and Industry / Xiuzhi Susan Sun / Soy protein is one of the most promising bio-degradable adhesives, with great potential as alternatives synthetic petroleum based adhesives for wood composite industries. However, its intrinsic drawbacks such as low water resistance, high viscosity, and short shelf life still limit its broad application. In this research, soy protein was further modified and characterized to improve adhesion properties, flow-ability, water resistance, and long shelf life, which could facilitate the industrialization of soy protein based adhesives. In this study, we exploited the in situ sodium bisulfite (NaHSO3) modification on soy protein in soy flour-water extracts, and then the modified soy protein was obtained through acid precipitation. First, different concentrations of NaHSO3 were used to modify soy flour slurry, then glycinin-rich and β-conglycinin-rich fractions were precipitated at pH 5.4 (SP 5.4) and pH 4.5 (SP 4.5), respectively. Unmodified sample SP 5.4 and SP 4.5 showed clay-like properties and viscoelastic properties, respectively; whereas with addition of NaHSO3 in range of 2-8 g/L, both SP 5.4 and SP 4.5 had the viscous cohesive phase with good handability and flow-ability. The overall adhesion performance of SP 4.5 was better than SP 5.4; the wet strength of these two fractions was in the range of 2.5-3.2 MPa compared to 1.6 MPa of control soy protein isolate. Then soy protein with various β-conglycinin/glycinin (7S/11S) ratios were extracted from soy flour slurry and characterized for adhesion properties based on the different solubility of 7S and 11S globulins. Seven glycinin-rich soy protein fractions and six β- conglycinin-rich soy protein fractions were obtained. According to the morphology, viscosity, and particle size results, we proposed that proper protein-protein interaction, hydration capacity (glycinin-rich fractions), and certain 7S/11S ratios (β-conglycinin-rich fractions) in modified soy protein are crucial to continuous protein phase formation. The viscous cohesive samples were stable for up to several months without phase separation at room temperature, with the wet adhesion strength of 2.0-2.8 MPa. The soy protein modified with NaHSO3 showed good compatibility with commercial glues applied on plywood and paper labeling fields. The modified soy protein made some functional groups, carboxylic (-COOH), hydroxyl (-OH) and amino groups (-NH2) available, which cross-linked with hydroxymethyl groups (-CH2-OH) from urea formaldehyde (UF) wood glue. The modified soy protein (MSP) with pH 4.8 also acted as an acidic catalyst for the self-polymerization of UF based resin. The wet adhesion strength of MSP/UF blends (40/60) was 6.4 MPa with 100% wood cohesive failure, as compared to 4.66 MPa of UF. As to the paper labeling application, peel strength of MSP on glass substrate increased rapidly, with curing time much shorter than commercial polyvinyl acetate based adhesives (PVAc). And the MSP/ PVAc blends showed shorter curing time, higher water resistance and lower viscosity than pure PVAc. Chemical modification could also enhance the adhesion strength of MSP. 2-octen-1- ylsuccinic anhydride (OSA) was proved to be grafted on soy protein through reaction between amine, hydroxyl groups of protein and anhydride groups. The oily nature and hydrophobic long alkyl chains of OSA mainly contributed to the significant water resistance improvement of MSP.
329

Evaluation of soybean inoculant products and techniques to address soybean nodulation problems in Kansas

Larson, Kim January 1900 (has links)
Master of Science / Department of Agronomy / Kraig Roozeboom / Nitrogen fixation by Bradyrhizobium japonicum in soybean [Glycine max] is highly beneficial in soybean crop production. Nodulation issues have been encountered on fields new to growing soybeans in recent years in Kansas. The purpose of this research was to evaluate soybean nodulation performance under various situations and seed handling practices in order to educate producers on how to achieve reliable nodulation consistency in the field. The objectives of the study were to: 1) compare inoculant products using single and double rates and in combination with one another on fields with varying soybean history; 2) determine if there was a negative interaction between inoculant products and common seed treatments; and 3) discover the influence of inoculated seed storage conditions before planting on the rhizobia’s ability to successfully nodulate soybean roots. Field experiments were conducted on diverse Kansas sites in 2011 and 2012. Inoculant treatment and seed treatment interaction trials had ten and seven experimental sites respectively. Inoculated seed storage conditions were evaluated in a greenhouse experiment during the spring of 2013. All studies used a randomized complete block design with four replications. The Novozymes inoculant products generally provided superior nodulation performance over other company products in the study where soybean had not been in recent rotation with an average increase of 167% in nodule number verses the control. The combination of dry and liquid inoculant products provided a significant increase in root nodule number at five of the environments out of recent rotation with a 76% increase over single inoculant rates. Although there were early season nodulation differences between treatments in new soybean ground, these did not carry through to seed yield differences in the majority of research sites. Hot and dry summer conditions reduced yields, making detection of treatment differences difficult. There were no negative effects on nodulation performance with any of the seed treatments. Although soybean seed yield was 634 kg ha[superscript]-[superscript]1 greater for the Novozyme combination treatment compared to the check at one location in 2011, the control yielded as well or better than all other treatment/inoculant combinations, implying that yield differences were likely not related to inoculant treatments. At other sites, yield was not influenced by seed treatment and inoculant combinations. Results indicate that seed treatment formulations did not significantly impact bacterial inoculant product performance, soybean nodulation, or yield. Storage conditions had no effect on nodulation performance in the greenhouse study, likely due to survival of Bradyrhizobium japonicum in the heat-treated growth medium.
330

Identification and stability of acylated anthocyanins in purplefleshed sweetpotato p40

Xu, Jianteng January 1900 (has links)
Master of Science / Department of Food Science / Weiqun Wang / We previously selected a purple-fleshed sweetpotato p40 clone that has been shown to protect against colorectal cancer in a murine model. This study is to identify anthocyanins by using HPLC/MS-MS and assess the stability during various coking conditions. P40 possesses a high content of anthocyanins up to 13 mg/g dry matter. Total 12 acylated anthocyanins with caffeic, ferulic, and p-hydrobenzoic acid have been identified on either cyanidin or peonidin bases. The top three major anthocyanins are cyanidin 3-caffeoyl-p-hydroxybenzoyl sophoroside-5-glucoside, peonidin 3-caffeoyl sophoroside-5-glucoside, and cyanidin 3-(6'' -caffeoyl-6''-feruloylsophoroside)-5-glucoside, which account for an half of the total anthocyanin contents. Seven non-, mono-, or di-acylated cyanidin species and five mono- or di-acylated peonidin species contribute for 69% and 31% of total anthocyanins, respectively. Over 80% of total anthocyanins measured by acid hydrolysis were cyanidin derivatives. Therefore, as a cyanidin-predominated variety, p40 is unique when compared with other reported purple-fleshed sweetpotatoes that usually contain more peonidin than cyanidin. While baking does not impact overall contents of anthocyanins, steaming, high pressure cooking, microwaving, and frying significantly reduce 20% of total anthocyanin contents. Mono-acylated anthocyanins show a higher resistance against heat than di- and non-acylated. Among of which, cyaniding 3-p-hydroxybenzoylsophoroside-5-glucoside exhibits the best thermal stability. Better understanding of dietary anthocyanins and their stabilities may lead to the development of a functional anthocyanin-enriched sweetpotato product for health benefits.

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