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The Impact Of Dietary Supplementation Of Arginine During Gestation In A Commercial Swine Herd: I. Gilt Reproductive Performance, Elizabeth A. Hines, Matthew R. Romoser, Zoë E. Kiefer, Aileen F. Keating, Lance H. Baumgard, Jarad Niemi, Nicholas K. Gabler, John F. Patience, Benjamin Haberl, Noel H. Williams, Brian J. Kerr, Kevin J. Touchette, Jason W. Ross 2019 Iowa State University

The Impact Of Dietary Supplementation Of Arginine During Gestation In A Commercial Swine Herd: I. Gilt Reproductive Performance, Elizabeth A. Hines, Matthew R. Romoser, Zoë E. Kiefer, Aileen F. Keating, Lance H. Baumgard, Jarad Niemi, Nicholas K. Gabler, John F. Patience, Benjamin Haberl, Noel H. Williams, Brian J. Kerr, Kevin J. Touchette, Jason W. Ross

Aileen Keating

Supplemental Arg during gestation purportedly benefits fetal development. However, the benefits of a gestational Arg dietary strategy in commercial production are unclear. Therefore, objectives of this study examined Arg supplementation during different gestational stages and the effects on gilt reproductive performance. Pubertal gilts (n = 548) were allocated into four treatment groups: Control (n = 143; 0% supplemental Arg) or one of three supplemental Arg (1% as fed) treatments: from 15 to 45 d of gestation (n = 138; Early-Arg); from 15 d of gestation until farrowing (n = 139; Full-Arg); or from 85 d of gestation until farrowing (n = 128; Late-Arg). At farrowing ...


Cover Crop Adoption Decisions In Iowa: Insights From An In-Person Survey, M. Jimena Gonzalez-Ramirez, Catherine Kling, J. Gordon Arbuckle, Lois Wright Morton, Jean McGuire, Jamie Benning 2019 Manhattan College

Cover Crop Adoption Decisions In Iowa: Insights From An In-Person Survey, M. Jimena Gonzalez-Ramirez, Catherine Kling, J. Gordon Arbuckle, Lois Wright Morton, Jean Mcguire, Jamie Benning

J. Gordon Arbuckle

CURRENT NITROGEN and phosphorus applications in the Midwest have been connected to increasing water quality problems.


Conditional Causal Mediation Analysis Of Factors Associated With Cover Crop Adoption In Iowa, Usa, Danhyang Lee, J. Gordon Arbuckle, Zhengyuan Zhu, Laurie Nowatzke 2019 Iowa State University

Conditional Causal Mediation Analysis Of Factors Associated With Cover Crop Adoption In Iowa, Usa, Danhyang Lee, J. Gordon Arbuckle, Zhengyuan Zhu, Laurie Nowatzke

J. Gordon Arbuckle

The Iowa Nutrient Reduction Strategy is a statewide effort that aims to encourage voluntary adoption of conservation practices by farmers to reduce the loss of nitrogen and phosphorus that contribute to water quality impairments in the Upper Midwest and drive hypoxic conditions in the Gulf of Mexico. This work is an analysis of the first 2 years (2015–2016) of a 5‐year survey of Iowa farmers. We employ causal mediation analysis to examine the direct and indirect effects of key explanatory variables (e.g., information sources, nutrient management influences, involvement in watershed management activities, and conservation technical assistance) and ...


A Novel Ruminant Emission Measurement System: Part Ii. Commissioning, Guilherme D. N. Maia, Brett C. Ramirez, Angela R. Green, Yi Sun, Luis F. Rodríguez, Daniel W. Shike, Richard S. Gates 2019 Iowa State University

A Novel Ruminant Emission Measurement System: Part Ii. Commissioning, Guilherme D. N. Maia, Brett C. Ramirez, Angela R. Green, Yi Sun, Luis F. Rodríguez, Daniel W. Shike, Richard S. Gates

Brett Ramirez

The Ruminant Emission Measurement System (REMS) supports research on the relationships between bovine nutrition, genetics, and management strategies by measuring eructated CH4 emissions from ruminal activity. Part I of this series provides the description and design evaluation of the newly developed REMS using uncertainty analysis tools. Part II of this series describes REMS commissioning and documents the whole system and subsystem performance. Subsystem assessments included verification of chamber positive pressurization, thermal environmental control performance, and integrity of the gas sampling system. Integrity of the entire system was verified through a steady-state mass recovery percent (SSMRP) analysis, which compared the ...


A Novel Ruminant Emission Measurement System: Part I. Design Evaluation And Description, Guilherme D. N. Maia, Brett C. Ramirez, Angela R. Green, Luis F. Rodríguez, Jacob R. Segers, Daniel W. Shike, Richard S. Gates 2019 University of Illinois at Urbana-Champaign

A Novel Ruminant Emission Measurement System: Part I. Design Evaluation And Description, Guilherme D. N. Maia, Brett C. Ramirez, Angela R. Green, Luis F. Rodríguez, Jacob R. Segers, Daniel W. Shike, Richard S. Gates

Brett Ramirez

Methane (CH4) generated by cattle is both a major source of greenhouse gas emissions and a powerful indicator of feed conversion efficiency; thus, accurate quantification of CH4 production is required for addressing future global food security without neglecting environmental impacts. A newly developed Ruminant Emission Measurement System (REMS) supports research on the relationships between bovine nutrition, genetics, and management strategies by measuring eructated CH4 emissions from ruminal activity. REMS is a substantial improvement and extension of the chamber technique, which is considered the standard method to quantify ruminant CH4 generation. Part I of this two-part series describes the design and ...


A Novel Approach To Measure, Understand, And Assess The Thermal Environment In Grow-Finish Swine Facilities, Brett Carlos Ramirez 2019 Iowa State University

A Novel Approach To Measure, Understand, And Assess The Thermal Environment In Grow-Finish Swine Facilities, Brett Carlos Ramirez

Brett Ramirez

The thermal environment (TE) inside swine production systems substantially affects animal performance as well as facility natural resource usage; hence, our measurement, understanding, and assessment of the TE must be advanced to sustainably meet the animal-protein demand of the growing global population. The TE describes the parameters that influence heat exchange between an animal and its surroundings, with maximum animal performance achieved when minimal thermoregulatory effort is required. Instrumentation and analysis techniques connecting the impact of the TE on total heat loss and subsequently, to animal performance in intensive housing systems are limited. Therefore, the goals of this dissertation research ...


Development And Validation Of A Spatial And Temporal Thermal Environment Sensor Array And Data Acquisition System, Brett C. Ramirez, Yun Gao, Steven J. Hoff 2019 Iowa State University

Development And Validation Of A Spatial And Temporal Thermal Environment Sensor Array And Data Acquisition System, Brett C. Ramirez, Yun Gao, Steven J. Hoff

Brett Ramirez

The Thermal Environment (TE) inside swine facilities has a substantial impact on animal growth performance and facility energy usage; therefore, proper control and measurement are required to maintain the optimal TE that maximizes feed efficiency and consumes minimal resources. An inexpensive and novel sensor network capable of capturing the spatial and temporal distribution of TE is needed to help guide control feedback sensor placement and identify potential issues with the facility’s environmental modification system. Hence, the objectives of this research were to: (1) design and construct a Thermal Environment Sensor Array (TESA) and (2) preliminarily evaluate the ability to ...


Heat Stress Adaptations In Pigs, Edith J. Mayorga, David Renaudeau, Brett C. Ramirez, Jason W. Ross, Lance H. Baumgard 2019 Iowa State University

Heat Stress Adaptations In Pigs, Edith J. Mayorga, David Renaudeau, Brett C. Ramirez, Jason W. Ross, Lance H. Baumgard

Brett Ramirez

Implications

• Heat stress is a global issue constraining animal agriculture productivity, negatively affects welfare, and reduces production efficiency in many countries.

• The effects of heat stress on pig production will intensify, if climate change continues as predicted.

• To date, modifying the environment is the most effective way to mitigate the effects of heat stress.

• Identifying additional strategies (nutritional and genetics) to maximize pork production during the warm summer months is necessary to satiate a growing demand for high quality meat for human consumption.


Development And Evaluation Of An Evaporation Model For Predicting Sprinkler Interval Time, Jay D. Harmon, Brett C. Ramirez, Steven J. Hoff, John F. Patience 2019 Iowa State University

Development And Evaluation Of An Evaporation Model For Predicting Sprinkler Interval Time, Jay D. Harmon, Brett C. Ramirez, Steven J. Hoff, John F. Patience

Brett Ramirez

Heat stress in swine causes decreased productivity and economic losses; hence, heat stress mitigation techniques must be developed to be economically and resource efficient. Current cooling strategies for livestock facilities, such as evaporative coolers or sprinklers, are governed by the Water Vapor Pressure (WVP) concentration gradient between the air (a function of dry-bulb temperature; tdb, Relative Humidity; RH, and atmospheric pressure) and the saturated WVP at the wet surface. Traditional sprinkler control systems operate at fixed ‘off’ intervals (i.e., drying) regardless if the thermal environment (TE) has the capacity or not to evaporate the dispersed water. Therefore, the objectives ...


Impact Based Odor Control System, Brett C. Ramirez, Steven J. Hoff 2019 Iowa State University

Impact Based Odor Control System, Brett C. Ramirez, Steven J. Hoff

Brett Ramirez

Biofilters are an effective and economically feasible technique for mitigating odor and other gaseous emissions from livestock production systems. They consist of a media containing a biofilm, where microorganisms break down compounds in livestock building exhaust air into energy and nutrients for growth and reproduction. In addition to capital costs, continuous filtering of exhaust air from mechanically ventilated buildings can be expensive and not always required, if odor is considered nuisance; thus, an automated control system was designed to filter odorous air when surrounding neighbors are most likely to be impacted and bypass the biofilter when odor impact potential is ...


Commissioning Of A Segmented Wand For Evaluating Airflow Performance Of Fans In Livestock And Poultry Housing, Katlyn R. DeVoe, Steven J. Hoff, Yun Gao, Brett C. Ramirez 2019 Iowa State University

Commissioning Of A Segmented Wand For Evaluating Airflow Performance Of Fans In Livestock And Poultry Housing, Katlyn R. Devoe, Steven J. Hoff, Yun Gao, Brett C. Ramirez

Brett Ramirez

Ventilation rate estimates play an important role in evaluating the thermal environment and determining emission rates from livestock and poultry housing. Currently, the standard method to measure in situ ventilation rates is the Fan Assessment Numeration System (FANS). A similar sensing system is needed for extension personnel that eliminates the labor and set-up requirements of FANS. In order to efficiently and cost-effectively estimate ventilation rates, a Segmented Wand for Evaluating Airflow Performance (SWEAP) was developed. The objectives of this research were to: (i) design and construct a hand-held device capable of measuring in situ fan intake flowrate, (ii) evaluate SWEAP ...


Commissioning Of A Novel Animal Thermal Environment Replication And Measurement System, Brett C. Ramirez, Steven J. Hoff, Yun Gao, Jay D. Harmon 2019 Iowa State University

Commissioning Of A Novel Animal Thermal Environment Replication And Measurement System, Brett C. Ramirez, Steven J. Hoff, Yun Gao, Jay D. Harmon

Brett Ramirez

Thermal environment (TE) in livestock production systems effects the animal’s thermal comfort, feed efficiency, and the producer’s operating costs. Accurate assessment of the radiative component of TE requires Mean Radiant Temperature (tmr) measurement with a Black Globe Thermometer (BGT); however, these devices are cost prohibitive (if multiple are needed), have limited commercial availability, and lack confidence for a range of conditions commonly found in a swine facility. The objectives were to design, construct and commission a novel and well-documented TE simulation system named Animal Thermal Environment Replication and Measurement System (AThERMS). Simulations of different combinations of dry-bulb ...


Functional Performance Evaluation Of A Novel Thermal Environment Sensor Array, Brett C. Ramirez, Y. Gao, Steven J. Hoff, Jay D. Harmon 2019 Iowa State University

Functional Performance Evaluation Of A Novel Thermal Environment Sensor Array, Brett C. Ramirez, Y. Gao, Steven J. Hoff, Jay D. Harmon

Brett Ramirez

The thermal environment (TE) inside livestock and poultry facilities has a substantial impact on animal growth performance and facility energy usage; therefore, the TE must be quantified correctly to maintain the optimal TE that maximizes feed efficiency and consumes minimal resources. To achieve this goal, a TE sensor array (TESA) and accompanying data acquisition system were previously developed to measure dry-bulb temperature (tdb), black globe temperature, airspeed, and relative humidity (RH). While measurement of each parameter is useful individually, it is more informative when they are combined to estimate and assess the total impact that the TE has on an ...


Thermal Environment Performance And Uniformity Assessment For A Novel Swine Breeding And Gestation Facility, Jay D. Harmon, Brett C. Ramirez, Steven J. Hoff 2019 Iowa State University

Thermal Environment Performance And Uniformity Assessment For A Novel Swine Breeding And Gestation Facility, Jay D. Harmon, Brett C. Ramirez, Steven J. Hoff

Brett Ramirez

The Thermal Environment (TE) inside swine facilities has a substantial impact on animal performance and facility energy usage; therefore, proper control and measurement are required to maintain the optimal TE that maximizes performance and consumes minimal energy. Currently, controllers only monitor and describe the TE with dry-bulb temperature (tdb); however, tdb does not account for all the factors that influence the TE. Therefore, a novel Thermal Environment Sensor Array (TESA) network and accompanying data acquisition systems were developed for a preliminary investigation inside a commercial, ~800 hd, positive pressure ventilated, filtered breeding facility located in central Iowa. Data from the ...


An Image Acquisition System For Studying Behaviors Of Sows And Piglets In Farrowing Barns, Suzanne Leonard, Hongwei Xin, Tami Brown-Brandl, Brett C. Ramirez 2019 Iowa State University

An Image Acquisition System For Studying Behaviors Of Sows And Piglets In Farrowing Barns, Suzanne Leonard, Hongwei Xin, Tami Brown-Brandl, Brett C. Ramirez

Brett Ramirez

Behavior studies in commercial swine farrowing room environments often need to monitor each set of sow and piglets individually and simultaneously. Autonomous computer imaging systems can overcome this challenge. The system presented here utilizes a time of flight depth sensor and a digital camera to capture depth and digital images of each sow and litter, housed in individual farrowing stalls. Depth sensors were centered above the stalls on a triangular truss spanning the length of the farrowing room and mounted in waterproof boxes with attached lids, enabling them to easily be waterproofed when cleaning the farrowing room. Each depth sensor ...


Development, Validation And Application Of A Mobile Air Filter Testing Unit, Jay D. Harmon, Benjamin C. Smith, Brett C. Ramirez, Steven J. Hoff, John P. Stinn 2019 Iowa State University

Development, Validation And Application Of A Mobile Air Filter Testing Unit, Jay D. Harmon, Benjamin C. Smith, Brett C. Ramirez, Steven J. Hoff, John P. Stinn

Brett Ramirez

The recent shift in commercial swine breeding-gestation-farrowing facilities to incorporate filtered ventilation systems raises numerous questions about system performance and longevity of filters. It has been shown that air filtration with ASHRAE standard MERV 14, 15 and 16 type filters are effective at reducing the aerosol spread of PRRSV and Mycoplasma hypopneumonia. The areas that are lacking in current literature is relevant filter testing methodology and criteria for determining filter end of life in an agricultural setting. To address this, a mobile air filter testing unit (MAFT) was developed to address the testing needs for the swine industry to evaluate ...


Thermal Environment Assessment And Controller Performance Comparison For A Wean-Finish Barn, Jay D. Harmon, Brett C. Ramirez, Steven J. Hoff 2019 Iowa State University

Thermal Environment Assessment And Controller Performance Comparison For A Wean-Finish Barn, Jay D. Harmon, Brett C. Ramirez, Steven J. Hoff

Brett Ramirez

The thermal environment (TE) inside swine facilities has a substantial impact on animal growth performance and facility energy usage; therefore, proper control and measurement are required to maintain the optimal TE that maximizes feed efficiency and consumes minimal resources. An inexpensive and novel network of 44 thermal environment sensor arrays (TESAs) capable of capturing the spatial and temporal distribution of the TE were deployed in August 2016 inside a two-room (designated as North; N and South; S), wean-finish barn (~1200 hd and 22 TESAs per room) and placed about 1.8 m above the slatted floor. All TESAs simultaneously measured ...


Design And Feasibility Of An Impact-Based Odor Control System, Brett C. Ramirez, Steven J. Hoff, Lun Tong 2019 Iowa State University

Design And Feasibility Of An Impact-Based Odor Control System, Brett C. Ramirez, Steven J. Hoff, Lun Tong

Brett Ramirez

Legislation and rural communities are increasingly requesting reductions in odor emitted from swine production facilities. If odor is regarded solely as a nuisance, and not an environmental hazard (as in this research), such that the objective of treating ventilation exhaust air is to prevent odor from impacting nearby receptors, it is unnecessary to treat exhaust air when dispersed odor is not identifiable. This approach maximizes odor reduction potential when most needed, with economic benefit through decreased energy and resource usage by simply operating the mitigation device for less time. The objectives of this article were: to develop an on-off, real-time ...


Design And Feasibility Of A Novel Sprinkler Control Algorithm For Swine Heat Stress Alleviation, Brett C. Ramirez, Steven J. Hoff, Jay D. Harmon 2019 Iowa State University

Design And Feasibility Of A Novel Sprinkler Control Algorithm For Swine Heat Stress Alleviation, Brett C. Ramirez, Steven J. Hoff, Jay D. Harmon

Brett Ramirez

No abstract provided.


Ovarian Metabolism Of Xenobiotics, Poulomi Bhattacharya, Aileen F. Keating 2019 Iowa State University

Ovarian Metabolism Of Xenobiotics, Poulomi Bhattacharya, Aileen F. Keating

Aileen Keating

At birth, the mammalian ovary contains a finite number of primordial follicles, which once depleted, cannot be replaced. Xenobiotic exposures can destroy primordial follicles resulting in premature ovarian failure and, consequently, early entry into menopause. A number of chemical classes can induce premature ovarian failure, including environmental, chemotherapeutic and industrial exposures. While our knowledge on the mechanistic events that occur in the ovary with chemical exposures is increasing, our understanding of the ovary's capacity to metabolize such compounds is less established. This review will focus on three chemicals for which information on ovarian metabolism is known: trichloroethylene, 7,12-dimethylbenz ...


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