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Full-Text Articles in Life Sciences

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

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 ...


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

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 Aug 2019

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 ...


Physiological Mechanisms Through Which Heat Stress Compromises Reproduction In Pigs, Jason W. Ross, Benjamin J. Hale, Jacob T. Seibert, Matthew R. Romoser, Malavika K. Adur, Aileen F. Keating, Lance H. Baumgard Jul 2019

Physiological Mechanisms Through Which Heat Stress Compromises Reproduction In Pigs, Jason W. Ross, Benjamin J. Hale, Jacob T. Seibert, Matthew R. Romoser, Malavika K. Adur, Aileen F. Keating, Lance H. Baumgard

Aileen Keating

Seasonal variations in environmental temperatures impose added stress on domestic species bred for economically important production traits. These heat‐mediated stressors vary on a seasonal, daily, or spatial scale, and negatively impact behavior and reduce feed intake and growth rate, which inevitably lead to reduced herd productivity. The seasonal infertility observed in domestic swine is primarily characterized by depressed reproductive performance, which manifests as delayed puberty onset, reduced farrowing rates, and extended weaning‐to‐estrus intervals. Understanding the effects of heat stress at the organismal, cellular, and molecular level is a prerequisite to identifying mitigation strategies that should reduce the ...


Transcriptome Analysis Reveals Potential Mechanisms Underlying Differential Heart Development In Fast- And Slow-Growing Broilers Under Heat Stress, Jibin Zhang, Carl J. Schmidt, Susan J. Lamont Apr 2017

Transcriptome Analysis Reveals Potential Mechanisms Underlying Differential Heart Development In Fast- And Slow-Growing Broilers Under Heat Stress, Jibin Zhang, Carl J. Schmidt, Susan J. Lamont

Jibin Zhang

Background
Modern fast-growing broilers are susceptible to heart failure under heat stress because their relatively small hearts cannot meet increased need of blood pumping. To improve the cardiac tolerance to heat stress in modern broilers through breeding, we need to find the important genes and pathways that contribute to imbalanced cardiac development and frequent occurrence of heat-related heart dysfunction. Two broiler lines – Ross 708 and Illinois – were included in this study as a fast-growing model and a slow-growing model respectively. Each broiler line was separated to two groups at 21 days posthatch. One group was subjected to heat stress treatment ...


Heat Tolerance Of Kentucky Bluegrasses, Perennial Ryegrasses, And Annual Bluegrass, David J. Wehner, T. L. Watschke Apr 2008

Heat Tolerance Of Kentucky Bluegrasses, Perennial Ryegrasses, And Annual Bluegrass, David J. Wehner, T. L. Watschke

David J. Wehner

Use of cool-season turfgrasses in transitional environments is limited, in part, by their heat tolerance. Development of a rapid heat tolerance screening technique would be of value in determining the potential of turf•grasses for use in warmer areas. The heat tolerance of 22 Kentucky bluegrass (Poa pratensis L.) cultivars, Poa annua L., and four perennial ryegrass cultivars (Lolium perenne L.) was evaluated by exposing plants for 30 min to temperatures ranging from 41 to 49 C in single degree intervals. Ten-week-old plants, which had been grown under a low level of N fertilization and watered infrequently to maximize heat ...


Heat Tolerance Of Kentucky Bluegrasses, Perennial Ryegrasses, And Annual Bluegrass, David J. Wehner, T. L. Watschke Apr 2008

Heat Tolerance Of Kentucky Bluegrasses, Perennial Ryegrasses, And Annual Bluegrass, David J. Wehner, T. L. Watschke

David J. Wehner

Use of cool-season turfgrasses in transitional environments is limited, in part, by their heat tolerance. Development of a rapid heat tolerance screening technique would be of value in determining the potential of turf•grasses for use in warmer areas. The heat tolerance of 22 Kentucky bluegrass (Poa pratensis L.) cultivars, Poa annua L., and four perennial ryegrass cultivars (Lolium perenne L.) was evaluated by exposing plants for 30 min to temperatures ranging from 41 to 49 C in single degree intervals. Ten-week-old plants, which had been grown under a low level of N fertilization and watered infrequently to maximize heat ...