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Productivity Measures In Beef Cows And Calves Following A Single Subcutaneous Injection Of Extended-Release Eprinomectin, Claire Andresen Jan 2017

Productivity Measures In Beef Cows And Calves Following A Single Subcutaneous Injection Of Extended-Release Eprinomectin, Claire Andresen

Graduate Theses and Dissertations

The effect of a single subcutaneous injection of extended-release eprinomectin for parasite control on cow/calf performance was evaluated in a pair of studies. In the first study, a fall-calving Angus herd was utilized. Mature cows were treated with either extended-release eprinomectin (EPR) or a conventional injectable anthelmintic (CONV). Cows treated with EPR had better maintenance of BCS through calving and into breeding. Subsequent pregnancy rates were greater for EPR than CONV cows. Furthermore, calves from EPR dams were younger at weaning, but had greater weaning weights than calves from CONV dams. From the same fall-calving Angus herd, replacement heifers ...


New Models To Estimate Costs Of Us Farm Programs, Xiaohong Zhu Jan 2016

New Models To Estimate Costs Of Us Farm Programs, Xiaohong Zhu

Graduate Theses and Dissertations

In this study, I extended the stochastic model built by Babcock and Paulson (2012) to conduct a one-year cost projection for crop insurance in order to investigate its feasibility of being solely provided by private firms. Based on the 52 years’ yield data from 1961 to 2012, the risk consequences from insuring crop yield and revenue against losses are estimated to be far beyond what private insurers could bear on their own. However, reinsurance from the government provides an attractive incentive to insurance firms. Among the six insurance policies researched in this study, the minimum expected net underwriting gains to ...


Ratios And Benchmarks As Tools For Local Food Hub Decision-Making: A Comparative Case Study, Savanna May Lyons Jan 2016

Ratios And Benchmarks As Tools For Local Food Hub Decision-Making: A Comparative Case Study, Savanna May Lyons

Graduate Theses and Dissertations

Food hubs, or local food aggregation and distribution businesses, are triple-bottom-line firms that play an increasingly important role in connecting small and mid-sized farmers to wholesale and retail markets. This paper explores how food hubs can use their financial data to identify and address strengths and challenges in their operations. We propose a “dashboard” of key metrics and benchmarks for food hub managers, and apply it a comparative case study of four food hubs over three years of operations. We compare and contrast the liquidity, cash flow, efficiency, solvency and repayment capacity of the four cases, and analyze cross-cutting themes ...


Three Essays On Crop Yield, Crop Insurance And Climate Change, Lisha Li Jan 2015

Three Essays On Crop Yield, Crop Insurance And Climate Change, Lisha Li

Graduate Theses and Dissertations

The main subject of this dissertation includes the study of the impact of weather on crop yields and developing crop revenue insurance product. The dissertation limits its analysis to the state of Iowa because it's a critical corn production area in the United States. Chapter 2 introduced a dynamic linear model to measure weather-adjusted trends in Iowa corn yields. The weather factors consist of the amount of rainfall, temperature and a measurement of soil moisture. Results show a significant improved yield growth in the 1990s, controlling for the impact of weather. Results also indicate that the critical temperature varies ...


Three Studies On Applying Positive Mathematical Programming And Bayesian Analysis To Model Us Crop Supply, Michael Hudak Jan 2015

Three Studies On Applying Positive Mathematical Programming And Bayesian Analysis To Model Us Crop Supply, Michael Hudak

Graduate Theses and Dissertations

The purpose of this dissertation is to find a practical way of obtaining a reasonable crop supply model for the US using a limited dataset. This model can then be used for forecasting and impact modeling. The method that is central to this model is Positive Mathematical Programming (PMP) that allows for the calibration of a nonlinear programming model to mimic the observations. This method is improved by implementing Bayesian Analysis to allow for the model to consider a distribution for the supply elasticity.

Using this method a national model was formed using only five years of data. While there ...


Three Essays On Modeling Biofuel Feedstock Supply, Wei Zhou Jan 2015

Three Essays On Modeling Biofuel Feedstock Supply, Wei Zhou

Graduate Theses and Dissertations

The general theme of this dissertation is modeling biofuel feedstock supply. All three essays focuses on different topics relating to the theme. The first essay considers supply of corn stover for a commercial production of a cellulosic ethanol plant. The economic trade-offs in determining the plant size under uncertain future corn stover yields and cellulosic ethanol prices are analyzed. We also estimate the impacts on optimal plant sizes under two payment schemes for corn stover procurement: plant pays for transportation cost and farmers pay for the transportation cost. My second essay analyzes the impact of ethanol mandates on corn prices ...


Evaluating Impact Of Diet, Housing And Season Systems On Feedlot Cattle Finishing Programs, Josephat Gichobi Njoka Jan 2014

Evaluating Impact Of Diet, Housing And Season Systems On Feedlot Cattle Finishing Programs, Josephat Gichobi Njoka

Graduate Theses and Dissertations

ABSTRACT

A four-year study was conducted using 1,987 yearling steers of predominantly mixed British breeds with an average starting weight of approximately 700 lb. The overall objectives of this study was to evaluate feedlot performance, carcass characteristics and expected economic projections for placing steers on feed quarterly per year for a period of 4 yr in different housing-diet systems. A pen with an average of 20 steers was the experimental unit, which was replicated once at the start of every trial period. Treatments were 2-levels of diet, 3-levels of housing, and season with 4-levels per year. The two diets ...


Alternative Approaches For Sharing Machinery, Labor, And Other Resources Among Small- And Medium-Sized Agricultural Producers, Greg Colson Jan 2008

Alternative Approaches For Sharing Machinery, Labor, And Other Resources Among Small- And Medium-Sized Agricultural Producers, Greg Colson

Retrospective Theses and Dissertations

As the U.S. agriculture industry continues to become increasingly concentrated, the viability of small- and medium-sized farms faced with diminishing profit margins per unit of output hinges in part on their ability to expand operations. In this study, the solution to this problem of taking advantage of economies of scale through farm-level resource sharing arrangements is considered. Through a two phase data collection procedure, Midwestern farmer groups engaged in resource sharing arrangements were identified and investigated through a case study approach. Evidence from the case studies suggest that sharing of equipment and labor can yield not only financial benefits ...


Essays On Fall Fertilizer Application, Mira Nurmakhanova Jan 2008

Essays On Fall Fertilizer Application, Mira Nurmakhanova

Retrospective Theses and Dissertations

Increased use of nitrogen fertilizer in agricultural production has contributed to increased food production but also contributed to elevated concentration levels of nitrates in groundwater and surface water. High concentration levels of nitrates in drinking water supplied from groundwater and surface water have become a public concern because of their risks to human health.;One way to reduce nitrogen losses is to develop and apply technologies that enable farmers to more accurately match the amount and timing of fertilizer application to crop growth needs. It is best to apply nitrogen as close as possible to when crop needs it most ...


Three Essays On Risk And Uncertainty In Agriculture, Nicholas David Paulson Jan 2007

Three Essays On Risk And Uncertainty In Agriculture, Nicholas David Paulson

Retrospective Theses and Dissertations

The general theme of this dissertation is risk and uncertainty in agriculture, with each chapter addressing a specific topic related to agricultural risk and uncertainty. Chapter 2 examines the effects of production uncertainty on the types of contract structures used in specialty grain markets. A theoretical model of a contractual relationship between a monopsonistic processor and risk-neutral producers is presented. Two common contract structures, and their resulting effects on the sharing of production risk between buyer and seller, are compared. The spatial structure of yields and farm-level yield volatility are shown to have significant impacts on the processor's preferred ...


A Simulation Model Evaluating Costs Of Bovine Viral Diarrhea Virus (Bvdv) For A Typical U.S. Cow-Calf Producer And Benefits Of Multiple Test And Cull Strategies, Kelsey James Wittenberger Jan 2007

A Simulation Model Evaluating Costs Of Bovine Viral Diarrhea Virus (Bvdv) For A Typical U.S. Cow-Calf Producer And Benefits Of Multiple Test And Cull Strategies, Kelsey James Wittenberger

Retrospective Theses and Dissertations

Increasingly, veterinarian organizations in the United States recommend the control and eradication of Bovine Viral Diarrhea Virus (BVDV). Cow-calf producers comprise 35% of U.S. cattle; however, research on the effects of BVDV in these herds is limited. To gain a better understanding of the pathology of BVDV in cow-calf producers, a stochastic simulation model was developed in C++ to measure epidemiological and financial outcomes. Additional simulations were run to evaluate changes in producer profit for several test and cull strategies. Introducing a PI animal decreased profit by an average of {dollar}13,971 over 10 years. When a second ...


Three Essays On Contract Farming In China, Jianhua Zhu Jan 2007

Three Essays On Contract Farming In China, Jianhua Zhu

Retrospective Theses and Dissertations

Contract farming in China has grown rapidly over the past 10 years. The first part of this dissertation examines the evolution of contract farming, and explores the incentives to engage in contract farming, preferred contract provisions, and contract performance from the perspective of both Chinese farmers and contracting firms. Firm and household perceptions of contracting are assessed using data obtained from village and firm level surveys. Farmers identify price stability and market access as the key advantages to contracts, while firms consider improved product quality as the primary incentive to use contracts.;In Part II, the survey data are used ...


Incentives And Contract Design: A Case Study Of Farmland Lease Contracts In Us Agriculture , Keita Fukunaga Jan 2006

Incentives And Contract Design: A Case Study Of Farmland Lease Contracts In Us Agriculture , Keita Fukunaga

Retrospective Theses and Dissertations

In this dissertation, I have studied farmland lease contracts in U.S. agriculture. Using the data from the 1999 Agricultural Economics and Land Ownership Survey, I investigated the empirical determinants of contract design from the perspective of the principal-agent framework, which emphasizes the role of incentives. In the empirical analyses, I found evidence that incentives indeed play an important role in contract design. In chapter 2, I investigated the role of risk, transaction costs, and endogenous matching between the landlord and tenant in contract choice. I found that both risk and transaction costs affect contract choice. Furthermore, I found evidence ...


Three Essays On Food Quality And Transaction Costs , Chengyan Yue Jan 2006

Three Essays On Food Quality And Transaction Costs , Chengyan Yue

Retrospective Theses and Dissertations

Product quality and product differentiation have become increasingly important to producers and policymakers for explaining consumer choice over food products. Consumers are often willing to pay large price premiums for products with preferred attributes. Heterogeneity in quality increases the diversity of goods for consumers and can improve welfare. However, variation in quality also leads to higher transaction costs for consumers, producers and policymakers because quality attributes are hard to identify precisely and vary when the state of the world changes. The first essay addresses the issue of food-quality attributes driven by protectionist policy that inhibits exchange between two countries. Technical ...


Micro-Level Econometric And Water-Quality Modeling: Simulation Of Nutrient Management Policy Effects , Christopher Sean Burkart Jan 2006

Micro-Level Econometric And Water-Quality Modeling: Simulation Of Nutrient Management Policy Effects , Christopher Sean Burkart

Retrospective Theses and Dissertations

Large surface areas of lakes and streams are impaired by nutrient contributions from agricultural nonpoint sources. This research develops a fully integrated economic and water quality model of an actual watershed to assess alternative nutrient abatement polities in terms of their economic efficiency and water quality effects. The policies examined include fertilizer taxes, application rate caps, uniform reductions, and a cap-and-trade fertilizer application right trading scheme. A micro-econometric field scale model of nutrient application is estimated using USDA Agricultural Resource Management Survey (ARMS) data combined with prices and spatially detailed soil data. Estimation results are interfaced with the Soil and ...


An Analysis Of The Iowan Angler's Fishing License Renewal Decision, Ryan R. French Jan 2006

An Analysis Of The Iowan Angler's Fishing License Renewal Decision, Ryan R. French

Retrospective Theses and Dissertations

The number of annual fishing licenses sold in Iowa has been in decline for two decades and has limited the amount of funds available to the Iowa Department of Natural Resources for fisheries management. The Iowa DNR is focused on reversing this trend through targeted marketing and efficient management of fishing resources. An analysis of Iowa anglers is performed with these goals in mind using past surveys and current customer data. The product of this analysis is a model which predicts whether a past customer will renew their license in the upcoming year. A logit model is developed using license ...


Essays On International Trade, Endogenous Quality And Invasive Species Risk , Anh Thuy Tu Jan 2005

Essays On International Trade, Endogenous Quality And Invasive Species Risk , Anh Thuy Tu

Retrospective Theses and Dissertations

This dissertation studies the relation between international trade and two issues that have become the active fields of economic research: the firms' quality decisions and the invasive species risk.;On the quality choice, the dissertation focuses on the impact of Voluntary Import Expansions (VIEs) on firms' quality decisions. I model a vertically differentiated international duopoly, with one firm in each country. A domestic and an exporting firm choose the quality of their goods and then compete in the domestic market. Both quantity and price conjectures are considered. The paper investigates the case where the government of the exporting country imposes ...


Investment In The Stock Market And Value-Added Agricultural Businesses As Portfolio Investment Alternatives To Farm Expansion, Joshua David Roe Jan 2005

Investment In The Stock Market And Value-Added Agricultural Businesses As Portfolio Investment Alternatives To Farm Expansion, Joshua David Roe

Retrospective Theses and Dissertations

In the past decade, farmers have increasingly invested in value-added agriculture. Analysis of these investments compared to farm expansion by farmers was conducted from a portfolio optimization standpoint. Farms with similar investment patterns were identified by cluster analysis. When individual farm characteristics were analyzed to determine how these attributes affected investment choices, clear influences were found. In general, value-added agricultural investments were found to be an efficient investment alternative to farm expansion. Because of their larger risk, stock market investments play a smaller role in an optimized producer portfolio.


Three Essays On Rural Economic Growth , Georgeanne Michael Artz Jan 2005

Three Essays On Rural Economic Growth , Georgeanne Michael Artz

Retrospective Theses and Dissertations

This dissertation is a collection of three papers, each analyzing a particular issue related to economic growth in rural America. The first paper explores the problem of defining rural and the implications for measuring rural growth. It discusses the sample selection problem inherent in using classification methods based on population that change over time. Fast growing rural areas grow out of their rural status, so using the most recent definition of rural in an analysis of growth excludes the most successful places. The findings demonstrate that average economic performance of the areas remaining rural significantly understates the true performance of ...


Three Essays On The Economics Of Innovation , Harun Bulut Jan 2005

Three Essays On The Economics Of Innovation , Harun Bulut

Retrospective Theses and Dissertations

We have identified three specific problems in the economics of innovation and addressed each of them in separate essays in this thesis.;Essay 1 revisits the problem of inefficient diversification efforts of firms in a R&D race setting (Dasgupta and Maskin, 1987)1 by taking into account the fact that firms have the option of trade secrecy in addition to patents in protecting their inventions. This essay is theoretical in nature as we use a game-theoretic modeling of firms' project and IP choices in a R&D race. We find that the availability of multiple IPR protection instruments can move the paths chosen by firms engaged in a R&D race towards the social optimum.;Essay 2 refers to the adoption and diffusion stages of the innovation process as we look at the economic effects of the introduction of Genetically Modified (GM) food in the European Union (EU) agricultural and food system. We develop a partial equilibrium modeling of European agro food sector and calibrate the model's parameters by using the EU data in year 2000. We find ...


A Statistical Regression Model To Determine Financial Cash Flow For Wind Energy Based On Tax Structure, Matthew Dae Joong Ritsema Jan 2004

A Statistical Regression Model To Determine Financial Cash Flow For Wind Energy Based On Tax Structure, Matthew Dae Joong Ritsema

Retrospective Theses and Dissertations

A financial cash flow for wind turbines is based on an energy entity's tax structure. Using statistical regression of various wind turbines and wind maps, a theoretical model for energy output was calculated. The turbines were separated by the rated size of the turbine. With the theoretical model, financial output was generated for four different types of tax structures. A total of eight test cases were simulated. Special consideration was given to the impact of Production Tax Credits (PTC) and Renewable Energy Production Incentives (REPI). The object is to determine what type of business and tax structure would have ...


The Food Chain Of Sheep And Policy Implications On The Sheep Sector In Syria In Highlight Of International Arrangements, Samir Grad Jan 2004

The Food Chain Of Sheep And Policy Implications On The Sheep Sector In Syria In Highlight Of International Arrangements, Samir Grad

Retrospective Theses and Dissertations

The sheep sector in Syria is considered as one of the most important sectors in animal production because it is the first source of meat, the second source of milk, and an export-oriented sector. Therefore, the need has emerged to study its supply chain in order to identify its weaknesses and bottlenecks and make suggestions for improvement. Accordingly, the theoretical background of food marketing is briefly presented including the functions and tools used by analyzing the marketing process. Hereby, the focus is on the approaches used by analyzing the food chains from various perspectives. In this context, the major actors ...


The Impact Of Improved Nutrition On Labor Productivity And Gdp Growth Rate In Low- And Middle-Income Countries, Majd Abdulla Jan 2004

The Impact Of Improved Nutrition On Labor Productivity And Gdp Growth Rate In Low- And Middle-Income Countries, Majd Abdulla

Retrospective Theses and Dissertations

This study examined the effects of nutrition on the growth rate of country economies over time. Previous studies on this topic have resulted in debates among researchers over how significant nutritional effects are on individual country economies. For this study, data were collected for four decades (1960s, 1970, 1980s, and 1990s) for 43 low- and middle-income countries. The data were analyzed to determine the effect of nutrition, represented by dietary energy supply (DES), on the growth rate of gross domestic product (GDP) per worker and on labor productivity. The research utilized ordinary least squares, instrumental variables, and random effects regressions ...


Insuring Uncertainty In Value-Added Agriculture: Ethanol, Nicholas David Paulson Jan 2004

Insuring Uncertainty In Value-Added Agriculture: Ethanol, Nicholas David Paulson

Retrospective Theses and Dissertations

A wide variety of insurance products are currently available for agricultural producers to insure against yield or price risks in the markets for the raw commodities they produce. Value-added enterprises, such as ethanol production, have become increasingly popular among farmers over the last decade; however, insurance against declines in the value-added portion of their crops is not yet available. This paper outlines the development of an insurance product aimed at corn producers who are members of an ethanol production cooperative. The product mimics the gross margin level of a typical ethanol production facility, and has the potential to provide producers ...


The Economic Potential Of Switchgrass As A Viable Biofuel Alternative, Jennifer E. Reutzel Jan 2004

The Economic Potential Of Switchgrass As A Viable Biofuel Alternative, Jennifer E. Reutzel

Retrospective Theses and Dissertations

To be commercially viable as a bioenergy feedstock, switchgrass must be cost-competitive. Switchgrass production and delivery costs are calculated for the Chariton Valley Switchgrass Biomass Project located in the Chariton Valley, Iowa. Sensitivity analyses are performed to determine which variables have the greatest impact on cost. Switchgrass production costs would require higher than expected market prices, and therefore various incentive payment options are considered. The incentive payments attempt to encapsulate the positive environmental attributes from the production of switchgrass as well as using switchgrass as a clean energy coal substitute. A modified CRP payment, carbon payment, and green tag payment ...


Land Preservation Decisions: Theoretical And Empirical Analysis , Shikha Marwah Jan 2004

Land Preservation Decisions: Theoretical And Empirical Analysis , Shikha Marwah

Retrospective Theses and Dissertations

There is a great concern that human actions are leading to increased rates of extinction of species. Ecologists have pointed out that the most important threat to wildlife comes from habitat alteration. The rapidly increasing human population and the resulting pressing demand for food and living space are pushing highly diverse natural areas into agriculture and other alternative uses. Recognizing this, the Federal agencies and private organizations, such as the Nature Conservancy, are becoming increasingly engaged in programs for conservation of species, where habitat restoration is an important component. However, this conservation is costly and there is uncertainty in the ...


Supply Chain Management Of Differentiated Agricultural Products Under Imperfect Information , Miguel Alberto Carriquiry Jan 2004

Supply Chain Management Of Differentiated Agricultural Products Under Imperfect Information , Miguel Alberto Carriquiry

Retrospective Theses and Dissertations

Participants in a supply chain of agricultural value added products face two significant challenges. First, many of the costly distinctive traits being desired by consumers are difficult (if not impossible) to observe even after consumption. In order for markets for these classes of goods to develop, firms touting the quality of the product need to be trusted. Hence, maintaining an excellent reputation is essential for firms to keep their customers' good will. Secondly, production is conducted in an environment of yield uncertainty, making it impossible for producers and processors to predict with certainty either the quantity or the quality of ...


Panel Econometric Evidence Of Chinese Agricultural Household Behavior In The Later 1990s: Production Efficiency, Size Effects And Human Mobility , Zhuo Chen Jan 2004

Panel Econometric Evidence Of Chinese Agricultural Household Behavior In The Later 1990s: Production Efficiency, Size Effects And Human Mobility , Zhuo Chen

Retrospective Theses and Dissertations

The dissertation consists of three essays that analyze production efficiency, size effects and human mobility using a panel of 591 Chinese agricultural households in the later 1990s.;The first essay estimates technical efficiency through the framework of a translog stochastic production frontier with a behavioral inefficiency component. The results reveal a decreasing trend of output elasticities with respect to labor and fertilizer. The marginal effects of inefficiency terms show significant output gains by eliminating land fragmentation, improving access to education in rural area, and promoting specialization and mechanization.;The second essay examines land heterogeneities and the empirical inverse relationship in ...


Investment Analysis Of Deferring A Farmer Owned Ethanol Plant: Using Real Options, Ramanathan Shunmugavelu Jan 2003

Investment Analysis Of Deferring A Farmer Owned Ethanol Plant: Using Real Options, Ramanathan Shunmugavelu

Retrospective Theses and Dissertations

A farmers owned value-added (FOVA) business is often subject to changes in the political situations. So an investment analysis tool that incorporates uncertainty, such as real options is more appropriate. Application of real options is limited in FOVA businesses. In this thesis, the concept of real options is applied under the framework of a farmer owned ethanol plant. The impact of changes in the policy or political situations on ethanol industry is well known. Farmer investors that are currently interested in investing in an ethanol plant should decide whether it is worthwhile to invest now or wait for a year ...


A Stochastic Model Of Maize Gene Dispersal, David G. Ripplinger Jan 2003

A Stochastic Model Of Maize Gene Dispersal, David G. Ripplinger

Retrospective Theses and Dissertations

The spatial distribution of maize genes is predicted using a two dimensional Lagrangian stochastic (LS) model that meets sub-inertial and well-mixed conditions. Using wind data from central Iowa, a Weibull distribution is fit. From this distribution, a series of Monte Carlo simulations are run using the LS model in three forms. The final two forms of the model are based on USDA regulations for the production of pharmaceutical producing corn, demonstrating the model's suitability for analyzing the risk of transgene dispersal in maize. Special considerations are given to the large size of maize pollen, the likelihood of pollen seepage ...