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Full-Text Articles in Life Sciences

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 ...


Factors Affecting Timing And Intensity Of Calving Season Of Beef Cow-Calf Producers In The Midwest, Lee L. Schulz, Claire E. Andresen, Patrick J. Gunn Jan 2016

Factors Affecting Timing And Intensity Of Calving Season Of Beef Cow-Calf Producers In The Midwest, Lee L. Schulz, Claire E. Andresen, Patrick J. Gunn

Animal Industry Report

Despite demonstrated market incentives to adopt controlled calving seasons, many producers still have herds that calve somewhat broadly throughout the year. Primarydata, collected through a coordinated survey effort withUSDA’s National Agricultural Statistics Service, were usedto quantify factors that affect producers’ decisions regardingtiming and intensity of calving season. Ninety-seven, 50, 33,and 26% of farms calve in the spring (Mar, Apr, May),summer (Jun, Jul, Aug), fall (Sep, Oct, Nov), and winter(Dec, Jan, Feb), respectively. Twenty-two percent observeda calving season exclusively in the spring. Sixty-six percentof respondents indicated calving season was dictated byweather, 34% because of labor availability, and ...


Beef Species Symposium: Economic Considerations Related To U.S. Beef Herd Expansion, Glynn T. Tonsor, Lee L. Schulz Sep 2015

Beef Species Symposium: Economic Considerations Related To U.S. Beef Herd Expansion, Glynn T. Tonsor, Lee L. Schulz

Economics Publications

Significant attention perpetually surrounds possible changes in breeding herd inventories in the U.S. beef cattle industry. This article outlines economic considerations of U.S. herd expansion. Factors restricting expansion include land availability, increasing production efficiency, operator demographics, capital requirements, and commodity price volatility. Several offsetting factors support herd expansion including unprecedented cow–calf returns, ongoing global beef demand growth, and timing within the current cattle cycle. In addition to these industry-wide factors, several important variations in individual ranch considerations are outlined. The authors’ expectations on future herd dynamics are provided, highlighting broader implications for individual operations, industry leaders, and ...


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 ...


Energy Use In Pig Production: An Examination Of Current Iowa Systems, Peter J. Lammers, M. Douglas Kenealy, James B. Kliebenstein, Jay D. Harmon, Matthew J. Helmers, Mark S. Honeyman Mar 2012

Energy Use In Pig Production: An Examination Of Current Iowa Systems, Peter J. Lammers, M. Douglas Kenealy, James B. Kliebenstein, Jay D. Harmon, Matthew J. Helmers, Mark S. Honeyman

Agricultural and Biosystems Engineering Publications

This paper compares energy use for different pig production systems in Iowa, a leader in US swine production. Pig production systems include not only the growth and performance of the pigs, but also the supporting infrastructure of pig production. This supporting infrastructure includes swine housing, facility management, feedstuff provision, swine diets, and manure management. Six different facility type × diet formulation × cropping sequence scenarios were modeled and compared. The baseline system examined produces 15,600 pigs annually using confinement facilities and a corn-soybean cropping sequence. Diet formulations for the baseline system were corn-soybean meal diets that included the synthetic AA L-lysine ...


Effects Of A Premolt Calcium And Low-Energy Molt Program On Laying Hen Performance, Egg Quality, And Economics, Emily R. Dickey, Anna Johnson, Kenneth J. Stalder, Kristjan Bregendahl Feb 2012

Effects Of A Premolt Calcium And Low-Energy Molt Program On Laying Hen Performance, Egg Quality, And Economics, Emily R. Dickey, Anna Johnson, Kenneth J. Stalder, Kristjan Bregendahl

Animal Science Publications

The objectives of this study were to evaluate and compare the effects of production, physiology, egg quality, and economics of laying hens housed in a cage system when offered a calcium premolt treatment and low-energy molt diets versus a traditional feed withdrawal (FW) treatment during and after molt. In total, 981 Hy-Line W-36 laying hens (85 wk of age) housed 3 per cage were used. Six treatments were compared in a 2 × 3 factorial design with 2 calcium premolt treatments (fine and coarse) and 3 molt diets (FW, soybean hulls, and wheat middlings). The coarse Ca was a 50:50 ...


Nonsolar Energy Use And One-Hundred-Year Global Warming Potential Of Iowa Swine Feedstuffs And Feeding Strategies, Peter J. Lammers, M. Douglas Kenealy, James B. Kliebenstein, Jay D. Harmon, Matthew J. Helmers, Mark S. Honeyman Mar 2010

Nonsolar Energy Use And One-Hundred-Year Global Warming Potential Of Iowa Swine Feedstuffs And Feeding Strategies, Peter J. Lammers, M. Douglas Kenealy, James B. Kliebenstein, Jay D. Harmon, Matthew J. Helmers, Mark S. Honeyman

Agricultural and Biosystems Engineering Publications

Demand for nonsolar energy and concern about the implications of fossil fuel combustion have encouraged examination of energy use associated with agriculture. The United States is a global leader in pig production, and the United States swine industry is centered in Iowa. Feed is the largest individual input in pig production, but the energy consumption of the Iowa swine feed production chain has yet to be critically examined. This analysis examines nonsolar energy use and resulting 100-yr global warming potential (GWP) associated with the swine feed production chain, beginning with cultivation of crops and concluding with diet formulation. The nonsolar ...


Quantifying The Role Of Riparian Management To Control Non-Point Source Pollution Of Pasture And Cropland Streams, James R. Russell, Daniel G. Morrical, John Kovar, Daryl R. Strohbehn, John D. Lawrence, Mathew M. Haan, Shelly Lee Nellesen, Thomas M. Isenhart, Richard Schultz Jan 2009

Quantifying The Role Of Riparian Management To Control Non-Point Source Pollution Of Pasture And Cropland Streams, James R. Russell, Daniel G. Morrical, John Kovar, Daryl R. Strohbehn, John D. Lawrence, Mathew M. Haan, Shelly Lee Nellesen, Thomas M. Isenhart, Richard Schultz

Leopold Center Completed Grant Reports

Grazing management practices have the potential to mitigate some problems with sediment and phosphorus loading in pasture streams. The project demonstrated possible strategies to lessen grazing impacts on streams.


A Study Of The Factors That Influence Consumer Attitudes Towards Beef Products Using The Conjoint Market Analysis Tool, Brian E. Mennecke, Anthony M. Townsend, Dermot J. Hayes, Steven M. Lonergan Jan 2009

A Study Of The Factors That Influence Consumer Attitudes Towards Beef Products Using The Conjoint Market Analysis Tool, Brian E. Mennecke, Anthony M. Townsend, Dermot J. Hayes, Steven M. Lonergan

Leopold Center Completed Grant Reports

Beef producers looking for a competitive edge in today's markets need information about the qualities that consumers consider most important. Using conjoint marketing analysis allowed the investigators to sort out the most relevant characteristics for meat purchasers.


Business Organization And Coordination In Niche Hog Marketing, James Kliebenstein, Brent Hueth, Maro A. Ibarburu Jan 2008

Business Organization And Coordination In Niche Hog Marketing, James Kliebenstein, Brent Hueth, Maro A. Ibarburu

Leopold Center Completed Grant Reports

Niche hog marketing enterprises face a unique set of challenges. This study considered five critical management issues, and analyzed the workings of two niche pork markets in Iowa. Issues of market timing, product quality, process verification, business organization, and sharing of returns are discussed.


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 ...


Predicting Animals In Feedlot That Produce Discounted Carcasses, Maro A. Ibarburu, John D. Lawrence Jan 2005

Predicting Animals In Feedlot That Produce Discounted Carcasses, Maro A. Ibarburu, John D. Lawrence

Animal Industry Report

U.S. beef producers are striving to improve the quality of their product. Most packers send economic signals to producers by paying quality grade and yield grade premiums based on the USDA standards in an effort to reward the higher quality beef producers and receive better quality animals in their slaughter plants. But the premiums and discounts for quality and yield grade vary between plants and grids. Therefore, identifying the characteristics of the lot before deciding which plant or grid system to sell their cattle is of special relevance for the producers.


Valuing Double Vaccination In Feeder Cattle, Maro A. Ibarburu, Beth E. Doran, J. D. Lawrence Jan 2005

Valuing Double Vaccination In Feeder Cattle, Maro A. Ibarburu, Beth E. Doran, J. D. Lawrence

Animal Industry Report

Pre-conditioning is a calf management program that grew out of a concept that originated in Iowa in 1965. The program is designed to reduce risk, health problems and improve profitability for both cow-calf producers and cattle feeders. Dr. John Herrick, Extension Veterinarian at the ISU College of Veterinary Medicine, and Dr. Harold Amstutz of the American Association of Bovine Practitioners were instrumental in developing the preconditioning program and coordinating the delivery of the program with Cliff Iverson, Area Extension Livestock Specialist, and co-workers in southeast Iowa. Today, Iowa leads the nation in the size and scope of this program.


The Impact Of Prrs On The Pig Cost Of Production, Colin D. Johnson, John W. Mabry, James B. Kliebenstein, Eric Neumann Jan 2005

The Impact Of Prrs On The Pig Cost Of Production, Colin D. Johnson, John W. Mabry, James B. Kliebenstein, Eric Neumann

Animal Industry Report

Porcine Reproductive and Respiratory Syndrome (PRRS) has had a significant impact on the profitability of swine production. As a means to quantify the financial impact of PRRS to the U.S. swine industry, a study was conducted. This study utilized case studies and a Delphi survey to identify the various impacts PRRS has on farms. Results suggest that impacts to individual farms vary greatly but aggregated data for approximately 100 million market swine being sold each year in the U.S., estimates PRRS adds somewhere between $5.60 and $7.62 to the cost per head sold.


Opportunities And Challenges For Dairy Steer Production In Northwest Iowa, Beth E. Doran, Ron Orth, John D. Lawrence Jan 2004

Opportunities And Challenges For Dairy Steer Production In Northwest Iowa, Beth E. Doran, Ron Orth, John D. Lawrence

Beef Research Report, 2003

A dairy steer survey, co-sponsored by Iowa State University Extension and the Iowa Institute for Cooperatives, was mailed to 635 cattle producers in northwest Iowa to assay the potential opportunities and challenges of feeding dairy steers. Replies from 177 surveys were summarized. Thirty-seven percent cited profitability as the major reason they had fed dairy steers. In comparing beef and dairy steers, reduced feeder calf cost was cited as an advantage with dairy steers. However, market access, finished market price and feed efficiency of dairy steers rated poorer than with beef steers. The biggest challenge to dairy steer production was market ...


Minimizing The Use Of Antibiotics In Pork Production, Palmer J. Holden, John Carr, Mark S. Honeyman, James B. Kliebenstein, James D. Mckean, Jay D. Harmon, John W. Mabry, Sherry Hoyer Oct 2002

Minimizing The Use Of Antibiotics In Pork Production, Palmer J. Holden, John Carr, Mark S. Honeyman, James B. Kliebenstein, James D. Mckean, Jay D. Harmon, John W. Mabry, Sherry Hoyer

Iowa Pork Industry Center Fact Sheets

Details on minimizing antibiotic use in pork production such as reducing stress. Other issues to consider include biosecurity measures and increased costs of producing antibiotic-free pigs.


The Economics Of Finishing Pigs In Hoop Structures And Confinement Facilities: A Summer Comparison, Benjamin Larson, James B. Kliebenstein, Mark S. Honeyman, Arlie D. Penner Jan 2002

The Economics Of Finishing Pigs In Hoop Structures And Confinement Facilities: A Summer Comparison, Benjamin Larson, James B. Kliebenstein, Mark S. Honeyman, Arlie D. Penner

Iowa State Research Farm Progress Reports

This report is part of an ongoing research project that is being conducted at the Iowa State University Rhodes Research Farm. This research is aimed at comparing two swine finishing facility types under a wide range of circumstances. This report provides results from a group of pigs finished during the summer season of 2000–2001. Evolution of the swine industry has forced industry members to reevaluate operations and utilize an increasing amount of risk management. A survey conducted in May 2001 showed that hoop buildings are becoming an important part of the swine industry. Hoop buildings became widely available in ...


An Economic Analysis Of Pork Production In Hoop And Confinement Facilities: A Winter Comparison, Benjamin Larson, James B. Kliebenstein, Mark S. Honeyman, Arlie D. Penner Jan 2002

An Economic Analysis Of Pork Production In Hoop And Confinement Facilities: A Winter Comparison, Benjamin Larson, James B. Kliebenstein, Mark S. Honeyman, Arlie D. Penner

Iowa State Research Farm Progress Reports

This report is part of an ongoing research project that is being conducted at the Iowa State University Rhodes Research Farm. This research is aimed at comparing two swine finishing facility types under a wide range of circumstances. This report provides results from a group of pigs finished during the winter season of 2000–2001. The evolution of the swine industry has forced industry members to reevaluate their operations and utilize an increasing amount of risk management. A survey conducted in May of 2001 showed that hoop buildings are becoming an increasingly important part of the swine industry. Hoop buildings ...


An Analysis Of The Cost Of Producing Pork In Hoop Structures And Confinement During The Summer, Benjamin Larson, James B. Kliebenstein, Mark S. Honeyman, Arlie D. Penner Jan 2001

An Analysis Of The Cost Of Producing Pork In Hoop Structures And Confinement During The Summer, Benjamin Larson, James B. Kliebenstein, Mark S. Honeyman, Arlie D. Penner

Iowa State Research Farm Progress Reports

This research compares pork production in two types of production facilities. Information for the fourth group of pigs, which was fed from June 1999 to October 1999 at the Rhodes Research and Demonstration Farm, is provided. Results will be evaluated using the actual production efficiency numbers and the average or typical costs for feeder pigs, feed, etc., along with average market hog prices. This allows for comparison of expected costs and returns for normal input cost and hog price conditions.


Numerical Optimization Of Recursive Systems Of Equations With An Application To Optimal Swine Genetic Selection , Richard Edmund Hawkins Jan 1999

Numerical Optimization Of Recursive Systems Of Equations With An Application To Optimal Swine Genetic Selection , Richard Edmund Hawkins

Retrospective Theses and Dissertations

A new dynamic programming method is developed for numerical optimization of recursive systems of equations, in which continuous choice variables determine the allowed choices in subsequent stages of the problem. The method works by dynamically creating bubbles, or subspaces, of the total search space, allowing the indexing of states visited for later use, and taking advantage of the fact that states adjacent to a visited state are likely to be visited. The method thereby allows search of spaces far larger than would traditionally be permitted by memory limitations. The search allows an infinite planning horizon, and tests at each stage ...


Television Advertising's Effect On The Demand For Different Types Of Fresh Beef: A Gibbs Sampling Approach, Jeremy Todd Benson Jan 1996

Television Advertising's Effect On The Demand For Different Types Of Fresh Beef: A Gibbs Sampling Approach, Jeremy Todd Benson

Retrospective Theses and Dissertations

No abstract provided.


Optimal Efficiency In The Use Of Iowa's Energy, Soil, And Feed Resources For Beef Production, James R. Russell, Allen H. Trenkle, Daryl R. Strohbehn, Walter F. Wedin, Stephen K. Barnhart, Arne Hallam, Mark S. Honeyman Jan 1992

Optimal Efficiency In The Use Of Iowa's Energy, Soil, And Feed Resources For Beef Production, James R. Russell, Allen H. Trenkle, Daryl R. Strohbehn, Walter F. Wedin, Stephen K. Barnhart, Arne Hallam, Mark S. Honeyman

Leopold Center Completed Grant Reports

Soil erodes over six times faster from cultivated Iowa cropland than from pastureland, even though almost 12 percent more of the pastureland acres are classified as highly erodible than the cropland acres. Because of serious concern about excessive erosion of Iowa's topsoil, profitable alternatives to row-crop production are needed for soils like those found in much of southern Iowa.


U.S. Livestock Production And Factor Demand: A Multiproduct Dynamic Dual Approach, K. Eswaramoorthy Jan 1991

U.S. Livestock Production And Factor Demand: A Multiproduct Dynamic Dual Approach, K. Eswaramoorthy

Retrospective Theses and Dissertations

There is a need for modeling livestock production and factor use incorporating the interlinked dynamics of breeding herd adjustments in a theoretically consistent manner. Therefore, a multiple input-multiple output theoretical model is developed based on the adjustment cost hypothesis of production relationship involving sluggish adjustments of quasi-fixed inputs. Employing the results of intertemporal analogue of Hotelling's lemma, a system of equations of optimal output supply, variable input demand, and quasi-fixed inputs (livestock breeding herds) investment is derived. Various issues like aggregation, expectation formation, and nonjointness in implementing this theoretical model are appraised.;A normalized quadratic value function is used ...


Response Analysis Of Beef Feedlot Gain With Respect To Genetic And Environmental Inputs, Bryan Edwin Melton Jan 1976

Response Analysis Of Beef Feedlot Gain With Respect To Genetic And Environmental Inputs, Bryan Edwin Melton

Retrospective Theses and Dissertations

No abstract provided.


The Effect Of The Hog-Corn Ratio On Swine Production In Iowa, Nathan Frank Burnham Jan 1972

The Effect Of The Hog-Corn Ratio On Swine Production In Iowa, Nathan Frank Burnham

Retrospective Theses and Dissertations

No abstract provided.


Optimum Swine Production And Marketing Strategies With Limited Farrowing And Finishing Space, Michael S. Hanrahan Jan 1972

Optimum Swine Production And Marketing Strategies With Limited Farrowing And Finishing Space, Michael S. Hanrahan

Retrospective Theses and Dissertations

No abstract provided.


Economies Of Size In Swine Production: A Normative Approach, Terry E. Crall Jan 1972

Economies Of Size In Swine Production: A Normative Approach, Terry E. Crall

Retrospective Theses and Dissertations

No abstract provided.


An Analysis Of The Feeder Cattle Enterprise On Iowa Farms With The Use Of Linear Programming Techniques, James Roger Ahrenholz Jan 1969

An Analysis Of The Feeder Cattle Enterprise On Iowa Farms With The Use Of Linear Programming Techniques, James Roger Ahrenholz

Retrospective Theses and Dissertations

No abstract provided.


Quarterly Marketing Margin Equations For Pork, Beef And Lamb, Georg Karg Jan 1969

Quarterly Marketing Margin Equations For Pork, Beef And Lamb, Georg Karg

Retrospective Theses and Dissertations

No abstract provided.


The Optimum Number, Size, And Location Of Turkey Processing Plants In A Three State Area, Murill Patrick Halvorson Jan 1968

The Optimum Number, Size, And Location Of Turkey Processing Plants In A Three State Area, Murill Patrick Halvorson

Retrospective Theses and Dissertations

No abstract provided.