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All Graduate Theses and Dissertations

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The Effects Of Different Organic Pastures On Dairy Heifer Growth And Development, Jacob A. Hadfield Aug 2020

The Effects Of Different Organic Pastures On Dairy Heifer Growth And Development, Jacob A. Hadfield

All Graduate Theses and Dissertations

Raising dairy heifers in a certified organic setting can be difficult for producers. Conventionally, heifers are raised in a confined setting, and fed a total mixed ration (TMR) that is balanced daily to contain all the needed nutrients for developing heifers. Organic producers can use a TMR in their operations, but due to high organic feed costs, many choose to raise their heifers in pasture-based systems. While pasture-based systems may lower costs, heifers on pasture commonly have lower rates of gain, which can be financially burdensome to producers. Grass-legume pastures may help improve rates of gain in heifers on pasture-based ...


Influence Of Forage Diversity And Condensed Tannins On Livestock Foraging Behavior, Production And Environmental Impact, Sebastian P. Lagrange Aug 2020

Influence Of Forage Diversity And Condensed Tannins On Livestock Foraging Behavior, Production And Environmental Impact, Sebastian P. Lagrange

All Graduate Theses and Dissertations

Eating a combination of forages with different chemistries (i.e., nutrients, beneficial compounds such as tannins) may enhance ruminant nutrition and reduce environmental impacts relative to eating single forages. I explored the influence of offering sheep and cattle all possible combinations of tanniferous (i.e., plants with tannins; birdsfoot trefoil, sainfoin) and non-tanniferous legumes (i.e., plants without tannins; alfalfa) or their monocultures on animal performance, behavior, and methane and nitrogen (N) emissions. Offering choices among these legumes to penned sheep improved intake and diet digestibility relative to feeding monocultures. Mixtures selected by sheep were better digested than mixtures containing ...


Reusable Light-Activated Antimicrobial Materials Prepared With Food Ingredients, Andrew T. Gagon Aug 2020

Reusable Light-Activated Antimicrobial Materials Prepared With Food Ingredients, Andrew T. Gagon

All Graduate Theses and Dissertations

Microbial contamination and proliferation in food processing, distribution and storage continues to be a real risk in spite the wide variety of food processing and preservation techniques available. Some of these techniques (such as heat treatments and the use of chemical preservatives) may require substantial amounts of energy and their effects in the general population and the environment may be harmful. This has generated an interest over alternative methods of food preservation. The use of reusable light-activated materials may represent an effective approach. In this study, a polypropylene plastic was modified with either zein, which is found in corn, or ...


Interspecific Differences In Stressor Tolerance Drive Community-Level Changes In A Small Aquatic Ecosystem, Jennifer M. Weathered May 2020

Interspecific Differences In Stressor Tolerance Drive Community-Level Changes In A Small Aquatic Ecosystem, Jennifer M. Weathered

All Graduate Theses and Dissertations

The global human population is expected to reach 9.8 billion by 2050 and an increase in food yield will be needed to provide for the future generations. Insects are among the biggest threats to food production and are therefore the subject of intense chemical control through the application of pesticides. The ability of insects to evolve resistance to pesticides after repeated use has been documented. However, how evolved responses affect individuals’ behaviors, their interactions with others, and how these factors impact overall patterns in distribution remains relatively unexplored in the bromeliad.

The aquatic insect communities housed in water-holding tropical ...


The Influence Of Protein Concentration And Homogenization On Moisture Content, Curd Yield, And Fat Retention Of Model Cheese Made From Microfiltered Skim Milk Recombined With Cream, Richard Byron Geslison May 2020

The Influence Of Protein Concentration And Homogenization On Moisture Content, Curd Yield, And Fat Retention Of Model Cheese Made From Microfiltered Skim Milk Recombined With Cream, Richard Byron Geslison

All Graduate Theses and Dissertations

This project was funded by the Western Dairy Center at Utah State University as part of a multi-pronged approach to improve the current understanding of using concentrated milks in cheese making. Concentrated milk for this study was provided by South Dakota State University.

This study compared the effect of different concentration factors of milk on curd moisture levels, fat content, and cheese curd yields. To see if these results could be improved (i.e. remove more moisture and retain more fat) milk samples were also subjected to limited pressure homogenization (microfluidization) treatments.

It was found in the course of this ...


A Case Study Comparing The Life Skills Development And Knowledge In Youth Participants Of Horseless And Traditional Horse Programs In Utah, Haley M. Johnson May 2020

A Case Study Comparing The Life Skills Development And Knowledge In Youth Participants Of Horseless And Traditional Horse Programs In Utah, Haley M. Johnson

All Graduate Theses and Dissertations

Traditional horse 4-H programs develop life skills and knowledge in youth. Horseless horse programs lack evaluation for the same benefits. This study evaluated and compared four horseless and seven traditional horse participants from Washington County 4-H in Utah for gains in horse knowledge and development of 10 life skills that are commonly found in 4-H curriculum today: leadership, teamwork, self-responsibility, personal safety, problem solving, decision making, critical thinking, goal setting, communication, and concern for others.

The researcher conducted interviews to learn about life skill experiences of the horse program participants and discover what barriers prevented horseless youth from participating in ...


Perceptions And Behavioral Intentions Of Utah 4-H Equine Program Leaders In Teaching Equine Safety To Youth, Katelyn M. Huffman May 2020

Perceptions And Behavioral Intentions Of Utah 4-H Equine Program Leaders In Teaching Equine Safety To Youth, Katelyn M. Huffman

All Graduate Theses and Dissertations

There is an inherent risk associated with working with youth and large equine. The Utah 4-H Equine program is a volunteer-based program that seeks to properly educate youth on equine husbandry, this includes the topic of safe equine handling practices. The purpose of this study was to explore the perceptions and behavioral intentions of Utah 4-H Equine Program leaders about teaching equine safety, including attitudes, perceived behavioral controls and subjective norms. The survey instrument consisted of multiple choice, fill in the blank, and six-point Likert scale questions regarding personal demographics, experience teaching equine safety, attitudes towards safety, perceived behavioral controls ...


Club Athletes: Dietary Supplement Use And How The Registered Dietitian Can Better Serve This Population, Rachel E. Robbins May 2020

Club Athletes: Dietary Supplement Use And How The Registered Dietitian Can Better Serve This Population, Rachel E. Robbins

All Graduate Theses and Dissertations

Dietary supplements are a booming business in the United States. Currently over half of Americans have taken a dietary supplement in the last year. Collegiate and professional athletes are even more likely to take a dietary supplement to get a competitive edge over their opponents. The objective of this study was to assess dietary supplement use in club athletes at Utah State University. Club athletes are non-scholarship athletes associated with a university. They often do not the same level of funding or resources that NCAA or scholarship athletes have. A survey was sent to all 401 club athletes at Utah ...


An Evaluation Of Arthropod Assemblages In Great Salt Lake Wetland Habitats: Differences Between Native And Invasive Vegetation And Implications For Restoration, Emily E. Leonard May 2020

An Evaluation Of Arthropod Assemblages In Great Salt Lake Wetland Habitats: Differences Between Native And Invasive Vegetation And Implications For Restoration, Emily E. Leonard

All Graduate Theses and Dissertations

Wetlands provide important habitat for various birds. Invasive plants can disrupt wetland food webs by altering the arthropod assemblages (invertebrate animals such as spiders, mites, insects, centipedes, and millipedes) on which these birds rely. However, differences between the wetland arthropods found in invasive vs. native vegetation are poorly defined. Wetlands are often managed for the creation of bird habitat through invasive species removal and native plant revegetation, yet few studies have examined the effects of these restoration methods on arthropod bird food sources. Phragmites australis (common reed), is an aggressive grass species in wetlands surrounding the Great Salt Lake, Utah ...


Human-Wildlife Interactions In Bryce Canyon National Park, Chad H. Wildermuth May 2020

Human-Wildlife Interactions In Bryce Canyon National Park, Chad H. Wildermuth

All Graduate Theses and Dissertations

Public lands such as National Parks protect some of America’s most spectacular and iconic natural, cultural, and historic landscapes. These lands are managed with a goal of preserving their unique features for the recreational use of the public. Therefore, it is important to understand the effects, if any, that public visitation has on these natural systems. This study investigated human-wildlife interactions in Bryce Canyon National Park (BRCA), Utah in order to better understand factors that lead to human-wildlife conflicts and how the attitudes and perceptions of visitors affect their actions towards wildlife.

Observations of human-wildlife interactions were observed and ...


Forage Inventory And Modeling In Uintah And Ouray Reservation Rangelands, Scott N. Zimmer May 2020

Forage Inventory And Modeling In Uintah And Ouray Reservation Rangelands, Scott N. Zimmer

All Graduate Theses and Dissertations

The Uintah and Ouray Reservation in northeastern Utah has not been widely studied, and access to non-tribal members is highly restricted. We sampled vegetation to summarize condition in 300,000 acres of unsurveyed Reservation lands in 2017-2018, combining these data with data collected by the Bureau of Indian Affairs from 2010-2015 to complete an initial rangeland vegetation inventory of the Reservation. This survey was designed to inform management of the area by determining cattle stocking rates and overall ecological condition across the Reservation. Both the density of forage available to cattle and appropriate cattle stocking rates vary greatly throughout management ...


Forest Grouse Ecology And Management In The Bear River Range Northern Utah, Skyler Y. Farnsworth May 2020

Forest Grouse Ecology And Management In The Bear River Range Northern Utah, Skyler Y. Farnsworth

All Graduate Theses and Dissertations

To better manage dusky grouse (Dendragapus obscurus) and ruffed grouse (Bonasa umbellus), hereafter forest grouse, managers require better information on forest grouse population status and habitat selection. To address this need, from 2015-2017, I conducted research on a sympatric populations inhabiting the Bear River Range of northern Utah to develop a breeding survey protocol, assess habitat selection, evaluate dusky grouse response to livestock grazing, and determine hunter harvest rates.

The breeding census protocol that I developed compared listening intervals with and without electronic playback calls at designated survey stop locations. Using digital mapping software, I plotted the estimated location of ...


Effect Of Dietary Maillard Reaction Products On Insulin Sensitivity, Metabolic Inflammation And Intestinal Inflammation In Mice Fed The Total Western Diet, Siyu Xiao May 2020

Effect Of Dietary Maillard Reaction Products On Insulin Sensitivity, Metabolic Inflammation And Intestinal Inflammation In Mice Fed The Total Western Diet, Siyu Xiao

All Graduate Theses and Dissertations

Maillard reaction products (MRPs) are generated when proteins or amino acids are heated with reducing sugars. In previous studies, baking whole diet pellets at a high temperature has been the most common way to promote MRP formation. However, baking diets also induces other chemical reactions besides MRP production, for example lipid oxidation. In this study, only casein and sugars were cooked to generate MRPs. Thus, a complementary experiment was conducted to determine how baking diet pellets affects lipid oxidation.

Previous rodent studies showed MRPs either induced weight gain and or impaired glucose tolerance. On the other hand, dietary MRPs were ...


Effect Of Thermosonication On Viscosity Of Milk Concentrates And Milk Quality And Shelf Life, Vidita Deshpande May 2020

Effect Of Thermosonication On Viscosity Of Milk Concentrates And Milk Quality And Shelf Life, Vidita Deshpande

All Graduate Theses and Dissertations

Thermosonication is the application of soundwaves at temperatures ≥50°C. It can be used to improve functional properties, overall quality, and shelf life of dairy products. Milk is concentrated before being spray dried and currently milk concentration is limited by increased viscosity. Decreasing the viscosity of concentrates prior to spray drying could be economically beneficial to dairy processors. Results from this study showed that that thermosonication significantly reduced the viscosity of concentrates such as reconstituted milk protein concentrate (rMPC) and reconstituted skim milk powder (rSMP). This would allow for spray drying of these concentrates at a higher total solids with ...


Innovative Biological Solutions For Nitrogen Fixation, Mathangi Soundararajan May 2020

Innovative Biological Solutions For Nitrogen Fixation, Mathangi Soundararajan

All Graduate Theses and Dissertations

Nitrogen is an important part of biological molecules like proteins and DNA and hence is essential for life as we know it. The most commonly found form of nitrogen is dinitrogen gas (N2) in the atmosphere, which is not accessible to most organisms. Conversion of N2 into a usable form (ammonia), occurs through an energy-demanding reaction called nitrogen fixation. As we think about sending humans to Mars, there is a need to develop technologies for nitrogen fixation to produce fertilizer and other valuable compounds to support life in those harsh conditions.

The Haber-Bosch process is used in industries ...


North Dakota Greater Sage-Grouse (Centrocercus Urophasianus) Recovery Project: Using Translocation To Prevent State-Wide Extirpation And Develop Rangewide Protocols, Kade D. Lazenby May 2020

North Dakota Greater Sage-Grouse (Centrocercus Urophasianus) Recovery Project: Using Translocation To Prevent State-Wide Extirpation And Develop Rangewide Protocols, Kade D. Lazenby

All Graduate Theses and Dissertations

Greater sage-grouse (Centrocurcus urophasianus; hereafter sage-grouse) are the largest grouse species in North America. Sage-grouse occupy 11 western states, extending into North Dakota. North Dakota sage-grouse population is part of the Great Plains Management Zone. Conservation of sage-grouse has been on the forefront of conservation management 1990s. In 2015 the USFWS declared sage-grouse were not warranted for listing based on significant management efforts. Translocations of sage-grouse to prevent populations from extirpation are an example of these efforts.

Translocations have been described as movement and release of animals into a novel environment. There have been more than 7200 sage-grouse translocated during ...


The Utility Of Environmental Dna And Species Distribution Models In Assessing The Habitat Requirements Of Twelve Fish Species In Alaskan North Slope Rivers, James B. Eddings May 2020

The Utility Of Environmental Dna And Species Distribution Models In Assessing The Habitat Requirements Of Twelve Fish Species In Alaskan North Slope Rivers, James B. Eddings

All Graduate Theses and Dissertations

Subsistence fishing is a vital component of Alaska’s North Slope borough economy and culture that is being threatened by human disturbance. These threats mean the fish must be protected, but the size of the region makes conservation planning difficult. Fortunately, advances in species distribution models (SDMs), environmental DNA (eDNA), and remote sensing technologies provide potential to better understand species’ needs and guide management. The objectives of my study were to: (1) map the current habitat suitability for twelve fish species, occurring in Alaska’s North Slope,(2) determine if SDMs based on eDNA data performed similarly to, or improved ...


An Evaluation Of Management Options For The Clover Root Curculio (Sitona Hispidulus), A Pest Of Alfalfa (Medicago Sativa) In The Intermountain West, Kaitlin A. Rim May 2020

An Evaluation Of Management Options For The Clover Root Curculio (Sitona Hispidulus), A Pest Of Alfalfa (Medicago Sativa) In The Intermountain West, Kaitlin A. Rim

All Graduate Theses and Dissertations

The clover root curculio (CRC) is an important forage pest throughout North America. Extensive larval feeding on host roots has been associated with reduced stand establishment, disruption of nutrient and water uptake, increased secondary plant pathogen infection, decreased winter plant survival, and reductions in forage quality and yield. Due to the hidden nature of larvae in the soil, CRC is often overlooked and integrated pest management programs are limited as there is a lack of management options. First, I surveyed northern Utah alfalfa for CRC natural enemies, particularly insect-attacking nematodes and fungi (entomopathogens) that could be used in biological control ...


Salinity Tolerance In Kentucky Bluegrass Hybrids, Paul G. Harris May 2020

Salinity Tolerance In Kentucky Bluegrass Hybrids, Paul G. Harris

All Graduate Theses and Dissertations

Diminishing water sources in the Intermountain West have led to increased use of alternative sources of water. These sources, such as reclaimed water, generally have elevated salinity levels that may slow growth, and cause a decline in turfgrass quality. Kentucky bluegrass (Poa pratensis L.) is sensitive to salt stress, but is otherwise very well adapted to many turfgrass areas because of its dark color, durability, ability to recover from wear, and soft texture. Because of these positive traits, it has been the subject of selection for salt tolerance. This study was designed to evaluate the salt tolerance of hybrids from ...


Patterns Of Microbial Diversity And Community Composition In Slot Canyons, Rock Pools, And Other Ephemeral And Perennial Aquatic Habitats, Marley Madsen May 2020

Patterns Of Microbial Diversity And Community Composition In Slot Canyons, Rock Pools, And Other Ephemeral And Perennial Aquatic Habitats, Marley Madsen

All Graduate Theses and Dissertations

Microbes are the most diverse life forms on the planet and perform many important ecological functions. However, despite the abundance, diversity, and ecological importance of microbes they are often overlooked and understudied in many natural systems, including freshwater habitats. This thesis details the first ever investigation of the microbial diversity and community composition within fresh water rock pools and slot canyons of the Colorado Plateau, Utah. The purpose of the study was to determine the relative importance of various microbial community assembly processes. This thesis also includes a meta-analysis of the microbial alpha diversity in other perennial and ephemeral aquatic ...


Herbivory Changes Soil Microbial Communities And Greenhouse Gas Fluxes In High-Latitude Wetlands, Karen M. Foley May 2020

Herbivory Changes Soil Microbial Communities And Greenhouse Gas Fluxes In High-Latitude Wetlands, Karen M. Foley

All Graduate Theses and Dissertations

Herbivory by migratory animals in high-latitude ecosystems is known to impact greenhouse gas emissions from soils. However, few studies quantify the relationships between changes herbivores make to plant communities and soil conditions, and the biological interactions soil organisms have with their environment that result in changes to greenhouse gas emissions. These relationships are important to understand because they capture important carbon-climate feedbacks that may have implications for climate change policy and land management decisions, especially since high-latitude systems are experiencing unprecedented changes in climate.

In the Yukon-Kuskokwim (Y-K) Delta in western Alaska, herbivory by migratory geese affects the magnitude of ...


Effects Of Bovine Maternal Nutrient Restriction On Offspring Microrna And Mrna Expression And Muscle Fiber Type, Nikole E. Ineck May 2020

Effects Of Bovine Maternal Nutrient Restriction On Offspring Microrna And Mrna Expression And Muscle Fiber Type, Nikole E. Ineck

All Graduate Theses and Dissertations

For producers in more temperate areas, such as the Intermountain West, poor nutrition during the second trimester of gestation is common due to seasonal changes in forage and nutrient availability. The majority of muscle fibers are formed and adipogenesis is initiated in the second trimester, making it a critical time for skeletal muscle and adipose development in beef cattle. However, the extent to which these changes persist in the offspring postnatally is unknown. In this study, maternal nutrition was restricted during the second trimester in order to analyze the effects of maternal nutrient restriction on offspring skeletal muscle growth. Offspring ...


Disease Ecology And Adaptive Management Of Brucellosis In Greater Yellowstone Elk, Gavin G. Cotterill May 2020

Disease Ecology And Adaptive Management Of Brucellosis In Greater Yellowstone Elk, Gavin G. Cotterill

All Graduate Theses and Dissertations

Brucellosis is a bacterial infection that primarily affects livestock and can also be transmitted to humans. In the Greater Yellowstone Ecosystem (GYE), elk (Cervus canadensis) and bison (Bison bison) are habitual carriers of Brucella abortus, which arrived to the region with cattle over a century ago. The disease was eliminated from cattle in the United States through widespread control efforts, but is now periodically transmitted back to cattle on open rangelands where they can come into contact with fetal tissues and fluids from disease-induced abortions that occur among elk during the late winter and spring. In Wyoming, south of Yellowstone ...


Do Didymosphenia Geminata Blooms Affect Fishes In The Kootenai River Basin?, Niall G. Clancy May 2020

Do Didymosphenia Geminata Blooms Affect Fishes In The Kootenai River Basin?, Niall G. Clancy

All Graduate Theses and Dissertations

Didymosphenia geminata (Didymo) is a nuisance algae that can cover entire streambeds under certain environmental conditions. Numerous studies have shown that it changes the composition of stream invertebrates. Fishes in many headwaters are known to feed almost exclusively on invertebrates. Thus, there is concern changes to the amount or type of invertebrates caused by Didymo blooms will impact fishes such as trout, charr, and sculpin. In the Kootenai River basin of Montana and British Columbia, we examined stream invertebrates and fish diets, condition, and growth across 25 streams during the summers of 2018 and 2019. The severity of Didymo blooms ...


Crispr/Cas9-Mediated Gene Editing In Herda Equine, Joseph R. Hawkes May 2020

Crispr/Cas9-Mediated Gene Editing In Herda Equine, Joseph R. Hawkes

All Graduate Theses and Dissertations

HERDA (Heritable Equine Regional Dermal Asthenia) is a genetic skin disease mainly found in Quarter Horses, but also in Appaloosa and American Paint breeds. HERDA is similar to Ehlers-Danlos syndrome in humans, with symptoms including stretchy skin, hyperflexible joints, and, unique to HERDA equine, spontaneous skin sloughing. Horses affected by HERDA are not suitable for performing and are oftentimes euthanized. Some carriers for the HERDA-mutation are very competitive in the American Quarter Horse industry, especially in cutting events where it is believed, yet unproven, to give them an advantage with increased flexibility. It is also possible that the genomic locus ...


The Response Of Utah Lake's Plant And Algal Community Structure To Cultural Eutrophication, Leighton R. King Dec 2019

The Response Of Utah Lake's Plant And Algal Community Structure To Cultural Eutrophication, Leighton R. King

All Graduate Theses and Dissertations

Human activities have long had a negative impact on the water quality of freshwater lakes around the world. Utah Lake, located in north-central Utah, has been a subject of such impacts, as the lake experiences recurrent harmful algal blooms during the summer months. Lake warnings and closures have made the public increasingly aware of the ecological and economic impact of these blooms. The objectives of this study were to: 1) compare historical and present-day water quality and ecosystem conditions using environmental data contained in sediment cores, 2) identify whether, and when, Utah Lake transitioned from clearwater to turbid conditions, and ...


Exploring The Physiology And Evolution Of Hornworts, Tanner A. Robison Dec 2019

Exploring The Physiology And Evolution Of Hornworts, Tanner A. Robison

All Graduate Theses and Dissertations

Plants contain organelles called chloroplasts, which is where photosynthesis takes place. Chloroplasts also contain their own DNA, which is separate from the DNA in the nucleus. This DNA does not change much over evolutionary time, so it can be used to investigate relationships between organisms. Here we created a tool that makes it easier to analyze this chloroplast DNA as well making it easier to share complete chloroplast genomes on public databases. In addition, we also found a mobile element in the chloroplast DNA of a group of ferns, which appears to be driving structural changes in their genomes.


Agriculture Teacher Attitudes Regarding Gifted Education And Teaching Gifted Students In The Agriculture Classroom, Olivia M. Hile Dec 2019

Agriculture Teacher Attitudes Regarding Gifted Education And Teaching Gifted Students In The Agriculture Classroom, Olivia M. Hile

All Graduate Theses and Dissertations

Agriculture teachers are responsible for a wide variety of students in their classrooms. It was unclear before this research how much preservice teacher instruction agriculture teachers were receiving to prepare them to teach students identified as gifted. This research aimed to measure teacher attitudes, characterization of gifted students, professional development needs, and related demographic information. Of the agriculture teachers who completed a traditional teacher preparation program, 54.50% felt that they were adequately prepared to meet the needs of gifted students in their classroom.

Participants characterized gifted agriculture students as outstanding problem solvers, quick to memorize information, and excellent in ...


Evaluation Of A Proprietary Slow-Release Oxytocin Therapy And Return Of The Luteolytic Mechanism In Mares, Brendan Andrew Sarnecky Dec 2019

Evaluation Of A Proprietary Slow-Release Oxytocin Therapy And Return Of The Luteolytic Mechanism In Mares, Brendan Andrew Sarnecky

All Graduate Theses and Dissertations

Prolonging function of the corpus luteum (CL) is a method of suppressing estrus that maintains secretion of endogenous progesterone to keep mares out of heat naturally. The use of oxytocin to prolong CL function is becoming more popular. In these therapies, upregulation of cyclooxygenase-2 is inhibited, which impairs prostaglandin F2α ( PGF2α) production. Intramuscular (IM) administration of 60 IU of oxytocin once daily from 7 to 14 days after ovulation is currently the most common treatment protocol. Although that protocol is efficacious in ≥70% of treated mares, the need for daily administration is a drawback to its use. A proprietary slow-release ...


Enteric Methane And Nitrogen Emissions In Beef Cattle Grazing A Tannin-Containing Legume Relative To Feedlot And Traditional Pasture-Based Production Systems, Raúl David Guevara Ballesteros Dec 2019

Enteric Methane And Nitrogen Emissions In Beef Cattle Grazing A Tannin-Containing Legume Relative To Feedlot And Traditional Pasture-Based Production Systems, Raúl David Guevara Ballesteros

All Graduate Theses and Dissertations

Beef cattle production is highly criticized because of the high use of land and water resources, and by the pollution (e.g., the gas methane in a cow’s breath and nitrogen in urine) produced by cows fed in feedlots. In contrast to feedlots diets and grasses, some plants (e.g., legumes) contain bioactive compounds (condensed tannins) that reduce pollution and enhance animal nutrition. In my research, I observed that cows grazing a tannin-containing legume (birdsfoot trefoil; BFT) had methane emissions similar to cows fed a feedlot ration with comparable weight gains. Cows in the BFT treatment gained more weight ...