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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.
441

Trend yields and the crop insurance program

Smith, Matthew K. January 1900 (has links)
Master of Agribusiness / Department of Agricultural Economics / Allen M. Featherstone / Multiple Peril Crop Insurance (MPCI) is a federally subsidized crop insurance program designed to mitigate risk for farmers across the United States. Many changes in technology and weather have increased yields in recent years. This has caused some to argue for the crop insurance program to consider yield trends when setting yields for the producer. This thesis evaluates alternative Actual Production History (APH) methods for corn to determine differences in the methods and the resulting APH. The key issue to be evaluated is that a producer’s APH may not be reflective of their “yield goal.” The thesis examined how the APH can differ under alternative methods of calculating an APH. Some methods examined are currently used by the Risk Management Agency (RMA). Other methods are hypothetical alternatives. This study examines alternative methods on a national, county, and a farm level. This thesis demonstrates that adjusting APHs for yield trends provides a higher APH than an un-trended APH. The 7 Year Olympic Trended APH provides the highest APH in most cases for all the methods examined. The RMA Un-trended APH proved to provide the least yield on average for all methods examined. This demonstrates the importance of adjusting for yield trends to factor in agricultural technology advancements over time.
442

Nutritional, sensory, and quality attributes of heritage bred chicken and commercial broiler meat

Christiansen, Alexandra R. January 1900 (has links)
Master of Science / Department of Food Science / Elizabeth A. Boyle / Animal production factors can affect nutritional composition and quality of poultry meat. Quality attributes and fatty acid composition were evaluated on breast and thigh meat with skin from free range, heritage bred chickens (>116 day of age) (HB) and commercial broilers (<50 day of age) (CM). In addition, sensory and textural attributes were evaluated on breast and thigh meat of HB, and air or water chilled CM. Moisture and fat content was similar (P>0.05) between chicken types without skin. Thigh meat had at least 2.41% more fat (P<0.05) than breast meat; however, breast meat had at least 2.33% more moisture (P<0.05) regardless of skin inclusion or chicken type. Heritage meat with or without skin had a greater amount (P<0.05) of ω3 polyunsaturated fatty acids (PUFA) than CM regardless of chilling type and HB had a lower, more desirable ω6:ω3 ratio of 12.79 when compared to air or water chilled CM at 15.20 and 14.77, respectively. Heritage breast and thigh meat with skin contained 35.60 and 35.21% PUFA which was greater than (P<0.05) CM breast and thigh meat with skin at 20.96 and 20.45%, respectively. Whole carcass weight of CM, breast weight, and bone-in thigh weight was 71.30%, 148.0%, and 52.2% heavier (P<0.05), respectively, than HB weight. However, bone-in thigh yield was 2.1% higher (P<0.05) in HB. Commercial broiler breast and thigh meat was more tender (P<0.05) with higher myofibrillar tenderness and overall tenderness values and having less connective tissue than HB breast and thigh meat. Thigh meat from HB also had the highest (P<0.05) peak force values for Warner-Bratzler (3.47 kgf) and Allo-Kramer (7.22 kgf/g sample) shear tests. Thigh meat was perceived to be more juicy (P<0.05) and have more chicken flavor intensity (P<0.05) than breast meat. Heritage meat showed advantages in fatty acid profiles while CM meat showed advantages in yields and tenderness attributes.
443

Co-digestion of agricultural and industrial wastes

Callaghan, Fergal James January 1998 (has links)
Anaerobic digestion technology has not gained widespread acceptance on UK farms due mainly to the long return on investment periods involved. It has been suggested that co-digestion of agricultural and industrial wastes may enhance the economic viability of such installations. Batch and continuous digestion of cattle slurry and organic industrial wastes was carried out in specially constructed pilot plant digesters, to determine optimum mixtures of waste and digester loading rates. A total of 10 different wastes were tested, on a batch digestion basis, for their potential to co-digest with cattle slurry. Of these, 3 were chosen for continuous pilot plant trials, due to either a need to provide a disposal route for the waste, or positive effects of the waste on methane productivity. Chicken manure was found to slightly enhance methane productivity, but ammonia inhibition of methanogenic bacteria was noted over time. The organic fraction of municipal household waste (OFMSW) significantly enhanced digester methane productivity, while fish offal (FO) slightly enhanced methane productivity when added to the digester in small quantities, but quickly caused digester failure when added in larger amounts. An economic model of a digestion facility was developed and used to show the financial benefits of co-digestion.
444

Online cash grain exchange: examining factors impacting the level of webbased trades and potential future adoption of mobile technology

Heikes, Kevin January 1900 (has links)
Master of Agribusiness / Department of Agricultural Economics / Jason Bergtold / In the grain industry, producers have sold grain for a long time over the telephone. This thesis suggests significant changes in grain marketing strategies and why other methods of selling grain may help both producers and grain merchandisers be more effective with cash grain transactions. Specifically, the use of web-based applications that allow growers to make, manage and monitor grain offers and use mobile technology for grain marketing solutions. This thesis evaluates two key technology options for agricultural producers. First, the research evaluates factors that impact traded bushels on Farms Technology’s private internet technology trading platform, the Dynamic Pricing Platform (DPP). The second element of the research defines a model which examines likelihood of growers adopting mobile trading technology to increase grain marketing opportunities. A thorough understanding of these two marketing platforms will allow Farms Technology to increase the number of growers opting to use technology to execute cash grain sales, which is financially beneficial to the company. Results indicate that a number of online variables significantly impact online grain trade, in addition to factors that specifically influence the potential adoption of mobile technology by agricultural producers. Results help quantify many insights which Farms Technology has developed in relation to online grade trading and uncovered future possibilities in the online grade trading industry. Statically significant factors that impact grain traded on the DPP include: acres (farm size), on-farm storage, percent of grain sold over the phone, offered bushels, and whether or not farmers received text messages. With respect to mobile application adoption, results identified factors that significantly and positively impact the likelihood of mobile adoption, including: farmers with no cell phone, farmers that are currently receiving text messages, farmers owning a smart phone, and customer service rating for Farms Technology by the farmer. Variables that significantly and negatively impacted mobile adoption included: farmers currently selling on the DPP and farmers who believe the online DPP application is too difficult to use.
445

The impact and control of malignant catarrhal fever in Tanzania

Lankester, Felix John January 2016 (has links)
Malignant Catarrhal Fever (MCF), an often-lethal infectious disease, presents as a variable complex of lesions in susceptible ungulate species. The disease is caused by a -herpesvirus following transmission from an inapparent carrier host. Two major epidemiological forms exist: wildebeest-associated MCF (WA-MCF), in which the virus is transmitted to susceptible species by wildebeest calves less than approximately four months of age, and sheepassociated MCF (SA-MCF) in which the virus is spread by sheep (primarily adolescents). Due to the lack of an in-vitro propagation system for the causative agent of the more economically significant SA-MCF, and with the expectation that cross-protective immunity may be provided, vaccine development has focused on the more easily propagated alcelaphine herpesvirus-1 (AlHV-1) that causes WA-MCF. In 2008 a direct viral challenge trial showed that a novel vaccine, employing an attenuated AlHV-1 (atAlHV-1) `C5000 virus strain, protected British Friesian-Holstein (FH) cattle against an intranasal challenge with virulent AlHV-1 `C5000 virus. For cattle keeping people living near wildebeest calving areas in sub-Saharan Africa an effective vaccine would have value as it would release them from the costly annual disease avoidance strategy of having to move their herds away from the oncoming wildebeest. On the other hand, an effective vaccine will release herd owners from the need to avoid MCF, allowing them to graze their cattle alongside wildebeest on the highly nutritious pastures of the calving areas. As such conservationists have raised concerns that the development of a vaccine might lead to detrimental grazing competition. The principle objective of this study was to test the novel vaccine on Tanzanian shorthorn zebu cross cattle (SZC).We did this firstly using a natural challenge field trial (Chapter Two) which demonstrated that immunisation with the atAlHV-1 vaccine was well tolerated and induced an oro-nasopharyngeal AlHV-1-specific and -neutralising antibody response. This resulted in an immunity in SZC cattle that was partially protective and reduced naturally transmitted infection by 56%. We also demonstrated that non-fatal infections occurred with a much higher frequency than previously thought. Because the calculated efficacy of the vaccine was less than that seen in British FH cattle we wanted to determine whether host factors, particular to SZC cattle, had impacted the outcomes of the field trial. To do this we repeated the 2008 direct viral challenge trial using SZC cattle (Chapter Four). During this trial we also investigated whether the recombinant bacterial flagellin monomer (FliC), when used as an adjuvant, might improve the vaccine’s efficacy. The findings from this trial indicated that direct challenge with pathogenic AlHV-1 is effective at inducing MCF in SZC cattle and that FliC is not an appropriate adjuvant for this vaccine. Furthermore, with less control group cattle dying of MCF than expected we speculate that SZC cattle may have a degree of resistance to MCF that affords them protection from infection and developing fatal disease. In Chapter Three we investigated aspects of the epidemiology of MCF, specifically whether wildebeest placenta, long implicated by Maasai cattle owners as a source of MCF, might play a role in viral transmission. Additionally, through comparative sequence analysis, at two specific genes (A9.5 and ORF50) of wild-type and atAlHV-1, we investigated whether the `C5000 strain, the source of which was taken from Africa more than 40 years ago, was appropriate for vaccine development. The detection of AlHV-1 virus in approximately 50% of placentae indicated that infection can occur in-utero and that this tissue might play a role in disease transmission. And, despite describing three new alleles of the A9.5 gene (supporting previous evidence that this gene is polymorphic and encodes a secretory protein with interleukin-4 as the major homologue), the observation that the most frequently detected haplotypes, in both wild-type and attenuated AlHV-1, were identical suggests that AlHV-1 has a slow molecular clock and that the attenuated strain was appropriate for vaccine development. In Chapter Five we present the first quantitative assessment of the annual MCF avoidance costs that Maasai pastoralists incur. In particular we estimated that as a result of MCF avoidance 64% of the total daily milk yield during the MCF season was not available to be used by the 81% of the family unit remaining at the permanent boma. This represents an upper-bound loss of approximately 8% of a household0s annual income. Despite these considerable losses we concluded that, given an incidence of fatal MCF in cattle living in wildebeest calving areas of 5% to 10%, if herd owners were to stop trying to avoid MCF by allowing their cattle to graze alongside wildebeest, any gains made through increased availability of milk, improved body condition and reduced energy demands would be offset by an increase in MCF-incidence. With the development of an effective vaccine, however, this alternative strategy might become optimal. The overall conclusion we draw therefore is that, despite the substantial costs incurred each year avoiding MCF, the partial protection afforded by the novel vaccine strategy is not sufficient to warrant a wholesale change in disease avoidance strategy. Nonetheless, even the partial protection provided by this vaccine could be of value to protect animals that cannot be moved, for example where some of the herd remain at the boma to provide milk or where land-use changes make traditional disease avoidance difficult. Furthermore, the vaccine may offer a feasible solution to some of the current land-use challenges and conflicts, providing a degree of protection to valuable livestock where avoidance strategies are not possible, but with less risk of precipitating the potentially damaging environmental consequences, such as overgrazing of highly nutritious seasonal pastures, that might result if herd owners decide they no longer need to avoid wildebeest.
446

Ideology, culture change, and management patterns in the Israeli Kibbutz

Bar-Yoseph, Benjamin A. January 1997 (has links)
This thesis addresses the problem of the cultural change in the Israeli Kibbutz, its relevance to the Kibbutz ideology and its implication on Management patterns in the Kibbutz. The thesis is based on four hypotheses. Two of the hypotheses address the cultural changes and two address the changes in management patterns. The cultural change is hypothesised by assuming a change in life style and a change in the attitude to work as a value. The change in management patterns is hypothesised by assuming a change, at a policy level, of resource allocation and a change in the decision making process. The research includes several stages: • A literature research which established the historic cultural and ideological roots of the Kibbutz movement. • A collection of general statistics of the Kibbutz movement. • Five case studies - An in depth analysis of five individual Kibbutzim. A model of the Kibbutz values and principles is developed and used in analysing the changes in values and principles in the Kibbutz. The outcome of the research reveals that the Kibbutz is changing from an ideology based commune, which prefers values over matter and is ready to sacrifice individual freedom for the ideals, to a more bureaucratic organisation alming for profits that prefers individual freedom on equality and communality. The Kibbutz movement is turning from an agrarian closed system to a technically advanced community with open economy and culture. The research outcomes enhance Bertalaruy's claim that a culture within a culture has to change in order to survive. It also demonstrates that a cultural change is an incremental change. What seems to be a radical change is an aggregate result of several incremental changes. It is suggested that a radical change can not be implemented successfully in an organisation unless broken to incremental changes.
447

Income and bean consumption patterns in Zambia

Pele, Winnie Kasoma January 1900 (has links)
Master of Agribusiness / Department of Agricultural Economics / Vincent Amanor-Boadu / The literature shows that increases in incomes lead to changes in the allocation of income or expenditure shares to different food products. The purpose of this thesis is to identify the effect of income on expenditure share allocations among different food groups. The study was particularly interested in beans and how changes in incomes affect the share of bean expenditures. We used data from the 2010 Zambia Living Conditions Monitoring Survey (LCMS). The LCMS covers the whole country and provides segmentation of the respondents, across the region and rural versus urban. It also provides detailed information on the income and expenditure distributions of respondent households. This allowed for the achievement of the overall objective of this thesis: understanding how beans and other food products responded to income changes as well as other demographic and socio-economic variables. The food share is the proportion of total household income that was allocated to food. The results show that food averages about 40% of income but varied significantly across the four income groups. It was 92% for those earning less than ZMW300 per month and 37% for those earning between ZMW300 and ZMW750 per month. It was down to 22.6% for those earning between ZMW750 and ZMW2.1 million per month had a food share of total income of only 10.8%, similar to the average U.S. consumer. These averages were found to be statistically different across the income groups. We found that Zambians allocated about 40% of their food expenditure to cereals compared to 5% to pulses and 3.5% to beans. They allocated a higher proportion of their food expenditure to fruits and vegetables than to beans and/or to pulses. This shows that legumes are very low on the food hierarchy in Zambia. However, across income categories, it was found that consumers in the second income group (ZMW300 and ZMW750 per month) allocated the most of their food expenditure to beans, about 3.9%, while those in the highest income group (ZMW750 and ZMW2.1 million per month ) allocated the least, about 3%. The biggest influencing demographic factor for pulses and beans’ shares of food expenditure was locale, with urban consumers having about 1.1 and 0.8 percentage points higher share of food expenditures allocated to beans than rural consumers. The respective t-values were 15.58 and 16.96. All the demographic and socio-economic variables were statistically significant at or below the 5% level. There was no difference between the allocation of people in the highest income group and those in the lowest income group. The results suggest that if the long-term objective is to reap the nutritional benefits of beans, there may be value in focusing on two principal policy variables: education and income enhancement. However, because education is correlated with income, the benefits of undertaking this policy initiative would more than benefit the bean consumption. It should unleash across the economy a more productive workforce that understands the health benefits of its food choices.
448

Value optimization of sow byproducts through new business development

Oium-Zube, Teresa January 1900 (has links)
Master of Agribusiness / Department of Agricultural Economics / Ted Schroeder / Johnsonville Sausage’s core business is to produce premium fresh and ready to eat (RTE) sausage. To accomplish this on the fresh side of the business, the organization procures and slaughters all of their own animals. The type of animal that Johnsonville Sausage procures is called a “fancy sow”. This type of sow averages 500 pounds and has had three or more litters of piglets. Johnsonville Sausage is the largest procurer of this type of sow accounting for 23% of the overall market. The largest contributor to the finished product cost is the meat. Over the last two years, the organization’s business has been faced with a number of challenges related to mass liquidations within the hog industry as well as increased sow prices due to lower supplies. Specifically, these issues have impacted the expected profitability as an organization and lead Johnsonville Sausage to question whether the supply projections within the industry will meet future growth needs. Because of these factors, Johnsonville Sausage is looking at how they can create more value for the sow that is slaughtered in order to utilize the whole animal to its highest potential, increase overall profitability to the organization and increase available sow supply within the industry. Within the business today, 55% of a sow that is harvested goes towards making the meat formulations (batter) utilized in fresh sausage production. The other 45% of the sow can be broken down into three key areas: sales credits, drop credits and rendering. Items within these three areas are classified as by-products and are sold to industries such as human consumption, pet food, pharmaceutical, medical, academia, commercial fishing and rendering to name a few. The issue that Johnsonville Sausage faces is how to define new channels, create new products, and increase customer base and volume for those parts of the sow that are not utilized in fresh sausage production thus driving increased value for these by-product items. In conjunction with this, how do they create more profitability for those items that are consistently harvested and sold today? The focus of this research was to create a project portfolio for the by-product business within Johnsonville Sausage. The goal of the portfolio was to identify industries and projects that would drive the greatest profit maximization for the by-product business and in return achieve the greatest return per sow. To accomplish this, optimization models and net present value (NPV) analyses were utilized. Utilizing the tools, I found that within Johnsonville Sausage’s existing by-product business, they have the opportunity to increase profitability by 54% from what was achieved in 2010. In conjunction with this, a NPV analysis on a further processed pork loin was conducted. Results of this analysis proved that creating this type of concept for Johnsonville Sausage was a more value added solution financially as compared to the traditional manner in which pork loins are sold today.
449

Chemical mitigation of microbial pathogens in animal feed and ingredients

Cochrane, Roger Andrew January 1900 (has links)
Master of Science / Grain Science and Industry / Cassandra K. Jones / Feed mill biosecurity is a growing concern for the feed industries, especially since the entry of Porcine Epidemic Diarrhea Virus (PEDV) to the United States. Porcine Epidemic Diarrhea Virus (PEDV) is primarily transmitted by fecal-oral contamination. However, research has confirmed swine feed and ingredients as potential vectors of transmission, so strategies are needed to mitigate PEDV in feed. The objective of the first experiment was to evaluate the effectiveness of various chemical additives to prevent or mitigate PEDV in swine feed and ingredients that had been contaminated post-processing. Time, formaldehyde, medium chain fatty acids, essential oils, and organic acids all enhance the degradation of PEDV RNA in swine feed and ingredients, but their effectiveness varies within matrix. Notably, the medium chain fatty acids were equally as successful at mitigating PEDV as a commercially-available formaldehyde product. Salmonella is also another potential feed safety hazard in animal feed ingredients. Thermal mitigation of Salmonella in ingredients and feed manufacturing is effective, but it does not eliminate the potential for cross contamination. Therefore, the objective of the second experiment was to evaluate the effectiveness of chemicals to mitigate Salmonella cross-contamination in rendered proteins over time. Both chemical treatment and time reduced Salmonella concentrations, but their effectiveness was again matrix dependent. Chemical treatment with medium chain fatty acids or a commercial formaldehyde product was most effective at mitigating Salmonella in rendered protein meals. The final experiment was conducted to evaluate the effectiveness of a dry granular acid, sodium bisulfate (SBS; Jones-Hamilton, Co., Waldridge, OH), to mitigate contamination of Salmonella in poultry feed. A surrogate organism, Enterococcus faecium, was utilized for this research in order to evaluate the effectiveness of SBS. Thermal processing, SBS concentration, and time all impacted biological pathogen levels in poultry diets, and including a dry granular acid may be an effective method to reduce pathogen risk. However, the most significant reduction of Enterococcus faecium was due to thermal mitigation. Notably, pelleting reduced Enterococcus faecium by 2-3 logs on day 0. In summary, both thermal processing and chemical inclusion can be used to reduce the risk of microbial pathogens in feed.
450

Consumer acceptance of omega-3 enhanced beef in surveys and retail trials

Curran, Kassie January 1900 (has links)
Master of Science / Agricultural Economics / John A. Fox / This study examines consumer acceptance of omega-3 enhanced beef using data from a choice experiment and a retail trial. The retail trial was conducted in collaboration with La Vaca Meat Company, Littleton, CO which offered omega-3 enhanced beef products for sale both online and in-store. Prices were adjusted periodically, and online customers were surveyed to gather information about their purchase decisions. The choice experiment was included in an online survey conducted with a nationally representative sample of consumers. One version of the survey focused on ground beef and another focused on steak. Within each version separate treatments examined the impact of providing information about how levels of the most beneficial omega-3s could be enhanced in beef. The choice experiment evaluated how variation in meat attributes such as omega-3 content, safety, and tenderness influenced purchase decisions. Data from the choice experiment were analyzed using multinomial logit models. Results indicate that overall acceptance and willingness to pay for omega-3 enhanced beef was below that of grass-fed beef. Additional information about omega-3s increased willingness-to-pay for enhanced omega ground beef, but had no impact on willingness-to-pay for enhanced omega steak. The analysis showed significant heterogeneity in preferences, and, in particular, females had significantly higher willingness-to-pay for grass-fed ground beef than males. Average willingness-to-pay for grass-fed steak was estimated at $3.69/lb above conventionally raised product, compared to an estimated premium of $1.86/lb for enhanced omega steak. For ground beef the average premium for grass-fed product was estimated to be $1.27/lb compared to $0.79/lb for the enhanced omega product.

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