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Articles 2521 - 2550 of 36382
Full-Text Articles in Entire DC Network
Controlling Salmonella: Strategies For Feed, The Farm, And The Processing Plant, Tomi Obe, Timothy Boltz, Mike Kogut, Steven C. Ricke, Lasheda A. Brooks, Ken Macklin, Ashley Peterson
Controlling Salmonella: Strategies For Feed, The Farm, And The Processing Plant, Tomi Obe, Timothy Boltz, Mike Kogut, Steven C. Ricke, Lasheda A. Brooks, Ken Macklin, Ashley Peterson
Poultry Science Faculty Publications and Presentations
Controlling Salmonella in poultry is an ongoing food safety measure and while significant progress has been made, there is a need to continue to evaluate different strategies that include understanding Salmonella-poultry interaction, Salmonella-microbiota interactions, Salmonella genetics and response to adverse conditions, and preharvest and postharvest parameters that enable persistence. The purpose of this symposium is to discuss different strategies to consider from feed milling to the farm to the processing environment. This Poultry Science Association symposium paper is divided into 5 different sections that covers 1) immunological aspects of Salmonella control, 2) application of Salmonella genetics for targeted …
Impact Of Reducing Ammonia Concentration By Ozone Technology And Its Potential Improvement On Broiler Performance, Odilpio Quintana Ortega
Impact Of Reducing Ammonia Concentration By Ozone Technology And Its Potential Improvement On Broiler Performance, Odilpio Quintana Ortega
Graduate Theses and Dissertations
The employment of ozone in livestock production as a means of mitigating ammonia is used for enhancing air quality within animal confinement facilities, such as swine or poultry barns. Ammonia is a byproduct of animal excrement. Elevated ammonia concentrations can adversely affect the well-being of both animals and humans. The aim of this thesis was to investigate the effects of Ozone Technology Machine Unit (OTMU) utilization in poultry barns regarding ammonia concentration and its potential benefit in terms of broilers performance and welfare. In recent years, there has been a significant boom in technological advances. New devices that help mitigate …
Demographics, Sexual Dimorphism, And Ecological Aspects Of Ambystoma Annulatum (Ringed Salamander) In Northwest Arkansas, Usa, Brian M. Becker
Demographics, Sexual Dimorphism, And Ecological Aspects Of Ambystoma Annulatum (Ringed Salamander) In Northwest Arkansas, Usa, Brian M. Becker
Graduate Theses and Dissertations
The need to study and monitor amphibian populations is increasing along with the threats to their population stability and persistence in nature. Northwest Arkansas is one of the fastest growing areas in the nation and with that growth comes rapid changes in land use, massive alterations to habitats, habitat loss, and the introduction of nonnative plants and animals. Ambystoma annulatum (Ringed Salamander) is an Ambystomatid endemic to the Ozark and Ouachita Mountains of southern Missouri, northern and western Arkansas, and eastern Oklahoma giving it a relatively small distribution compared to most Ambystoma. Therefore, Arkansas constitutes a significant portion of the …
In Vitro And In Vivo Evaluation Of Antimicrobial Activity, Oocyst Sporulation Rate, Oocyst Integrity And Oocyst Infectivity In Eimeria Maxima M6 Oocyst Suspensions Treated With Chlorhexidine Salts In Comparison With Potassium Dichromate, Lauren Laverty
Graduate Theses and Dissertations
Eimeria species oocysts cause coccidiosis, one of the costliest diseases in the poultry industry. Coccidiosis infections cause significant economic losses due to reduced performance in chickens and turkeys. The objective of this thesis was to determine fecal bacterial recovery from chlorhexidine (CHX) salt suspensions containing Eimeria maxima M6 oocysts and evaluate the effect of CHX salts on oocysts during long-term cold storage. For bacterial recovery experiments, CHX digluconate and CHX gluconate were tested at different concentrations on poultry fecal slurries during oocyst shedding. Eimeria maxima M6 oocysts were evaluated in CHX salt suspensions to test the effect on oocyst degradation …
The Effects Of Probiotics And Environment On The Swine Gut Microbiome, Bin Zuo
The Effects Of Probiotics And Environment On The Swine Gut Microbiome, Bin Zuo
Graduate Theses and Dissertations
The gastrointestinal tract is crucial for nutrient absorption and immune system functionality. It employs a synergistic approach, merging physical and biochemical defenses, to counteract pathogens that enter through dietary or other external routes. This system also facilitates the breakdown of complex carbohydrates, a process beyond the host's innate capacity. In swine, gut microbiota early colonization plays a significant role in several physiological developments, shaped by a variety of determinants including maternal factors and environmental conditions. In the swine industry, the shift to indoor pig farming enhances efficiency but limits soil interaction, potentially impacting gut microbiota diversity. Additionally, the practice of …
Assessing The Morphological And Physiological Traits Of Smooth Brome Pastures Under Long Term Grazing And Nutrient Enrichment In Eastern Nebraska, Hassan Shehab
School of Natural Resources: Dissertations, Theses, and Student Research
Climate change together with the increase in demands for food, feed, fuel, and fiber are becoming a threat to sustainability and resilience of agriculture and pasture lands. Bromus inermis (smooth bromegrass) dominates pastures for cattle grazing in Eastern Nebraska, US, where it is planted in monocultures, and is considered high quality forage because of its palatability and high nutritional value for cattle, especially under intensive management practices. Sustainable management of these pastures is key to long-term resilience. This study aims to assess the performance of smooth bromegrass pastures to the combined effects of long-term management practices (since 2005) of fertilization …
The Influence Of Invasive Species On Fishers’ Satisfactions, Caroline M. Laplante
The Influence Of Invasive Species On Fishers’ Satisfactions, Caroline M. Laplante
School of Natural Resources: Dissertations, Theses, and Student Research
Invasives species are prevalent and widespread in North America. Outdoor recreational activities, such as fishing, introduce a point in which humans may interact with invasive species and have to adapt their own behaviors. Bigheaded carp in the Missouri River below Gavin’s Point Dam are a group of invasive fish species that were thought to be negatively relating to recreational fishers’ satisfactions. Using a content analysis and an importance-grid, we conclude that invasive species do not strongly relate to recreational paddlefish fishers’ satisfactions. Paddlefish fishers represent a small sub-set of recreational fishers in Nebraska and South Dakota. The content analysis revealed …
Understanding Avidities Of Recreational Activities For People Possessing Fishing Licenses And Residing In Urban Environments, Kyle F. Hansen
Understanding Avidities Of Recreational Activities For People Possessing Fishing Licenses And Residing In Urban Environments, Kyle F. Hansen
School of Natural Resources: Dissertations, Theses, and Student Research
Recreational fishing is one of the world's most popular pastimes, wherein participation is associated with sociodemographic factors. Even so, fishing license sales are declining in the USA in conjunction with a reduction in rural populations as people move to urban areas. Thus, urban areas are constantly growing in population size, population diversity, and geographic size suggesting a need to understand fishing participation in these growing areas. Natural resource managers often use participation to understand recreationists, yet avidity could provide a new way to understand recreationists. The goal of our study is to understand what sociodemographic factors influence the fishing avidity …
Game-Theoretic Approaches To Optimal Resource Allocation And Defense Strategies In Herbaceous Plants, Molly R. Creagar
Game-Theoretic Approaches To Optimal Resource Allocation And Defense Strategies In Herbaceous Plants, Molly R. Creagar
Department of Mathematics: Dissertations, Theses, and Student Research
Empirical evidence suggests that the attractiveness of a plant to herbivores can be affected by the investment in defense by neighboring plants, as well as investment in defense by the focal plant. Thus, allocation to defense may not only be influenced by the frequency and intensity of herbivory but also by defense strategies employed by other plants in the environment. We incorporate a neighborhood defense effect by applying spatial evolutionary game theory to optimal resource allocation in plants where cooperators are plants investing in defense and defectors are plants that do not. We use a stochastic dynamic programming model, along …
Serranidae Spp. Neurocranium, Justin Abonce, David Kerstetter
Serranidae Spp. Neurocranium, Justin Abonce, David Kerstetter
All Scans: Kerstetter Fisheries and Avian Ecology 3D Scan Series
No abstract provided.
Mapping Density And Distribution Of Ptarmigan And Arctic Ground Squirrels Within Gyrfalcon Breeding Territories In Western Alaska, Michaela L. Gustafson
Mapping Density And Distribution Of Ptarmigan And Arctic Ground Squirrels Within Gyrfalcon Breeding Territories In Western Alaska, Michaela L. Gustafson
Boise State University Theses and Dissertations
Shifting climate patterns are modifying Arctic habitats, stressing the need to understand how rapid climate and habitat changes affect Arctic trophic webs. Despite their crucial role in illuminating the impacts of Arctic changes and their ripple effects on predators, like Gyrfalcons, small Arctic primary consumers remain insufficiently studied across their range. To address this gap, I sought to estimate the distribution and abundance of Gyrfalcons' top three prey species (Willow Ptarmigan, Rock Ptarmigan, and Arctic ground squirrels) within Gyrfalcon breeding territories on the Seward Peninsula, Alaska, USA. I also aimed to discern the relationships between different habitats and species’ abundance. …
How Beavers (Castor Canadensis) Affect Habitat Availability For Two Native Oregon Turtles: Actinemys Marmorata And Chrysemys Picta Bellii, Rodé Krige
University Honors Theses
Oregon is home to two native freshwater turtle species: the northwestern pond turtle and the western painted turtle. Both turtles are Oregon conservation strategy species with a status rating of sensitive, indicating declining populations. Oregon's decline in these turtle's populations is thought to be predominantly due to loss and degradation of habitat that results from development and urbanization. Beavers' ability to dam streams and create ponds may be creating habitat usable by turtles, but the relationship is under-studied. This study assessed water temperature, basking habitat, and overall turtle habitat suitability at beaver-dammed and control ponds in Portland, Oregon. Average basking …
Impacts Of Disturbance And Nutrient Addition On Coastal Dune Arthropod Communities, Kayla Beitzel
Impacts Of Disturbance And Nutrient Addition On Coastal Dune Arthropod Communities, Kayla Beitzel
Honors Theses
Coastal dune ecosystems are globally distributed ecosystems that occur from the tropics to the poles and serve as the first line of defense during storms. They are critical habitats for a variety of organisms and also play a critical role in stabilizing coastal habitats. These systems face increased pressure via urban development, recreational expansion, and sea-level rise (Newman et al. 2023; Webster et al. 2005). Insects are vital consumers in coastal ecosystems and act as regulators of plant growth. Low-diversity ecosystems, like coastal dune systems, often contain a higher abundance of low-diverse insect consumers (Ripple et al. 2021), which can …
Monitoring The Effectiveness Of Wildlife Exits And Bobcat Use Along A South Texas Highway, Jamie E. Langbein
Monitoring The Effectiveness Of Wildlife Exits And Bobcat Use Along A South Texas Highway, Jamie E. Langbein
Theses and Dissertations
Roadside exclusion fencing is commonly used to mitigate wildlife road mortalities and property damages caused by wildlife-vehicle collisions. A potential consequence is that animals may become trapped on the road by fencing. On State Highway 100 in South Texas, the Texas Department of Transportation installed ten wildlife exits (WE) allowing animals to exit the roadway through a modified opening in the fence. However, some individuals used the WE to access the roadway. In this study, a new design was implemented, with narrower openings, a ramp and a clear plastic one-way door. While the updated design prevented road access for wildlife, …
Renovating The Ipmu Via Internet Of Things For Pollutant Emission Estimations In Poultry Facilities, Joshua Dotto
Renovating The Ipmu Via Internet Of Things For Pollutant Emission Estimations In Poultry Facilities, Joshua Dotto
Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research
The emissions of ammonia (NH3), particulate matter (PM2.5), and carbon dioxide (CO2) are major concerns in poultry facilities. They can pose environmental concerns and nuances. Robust and affordable measurement systems are needed to accurately measure in-barn concentrations and quantify the emissions.
The Intelligent Portable Monitoring Unit (iPMU or PMU3) developed in 2016 was reconstructed into PMU4 to include upgraded NH3 and PM2.5 sensors and wireless connectivity for a low-cost, robust, and accurate air quality monitoring device with contactless data transfer using the concept of Internet of Things (IoT). In addition, a user-friendly …
Effects Of Short-Term Pesticides Exposure On Swimming Behavior, Tissue Morphology, Oxidative-Nitrative Stress, Antioxidant Expression, And Cellular Apoptosis In Kidneys Of Goldfish, Esmirna Cantú
Theses and Dissertations
The prevalence of pesticides in the aquatic environment continues to increase due to anthropogenic activities and poses a threat to aquatic organisms. The aim of this study was to determine the short-term exposure (one-week) of pesticide mixtures (metolachlor, linuron, isoproturon, tebucanazole, alconifen, atrazine, pendimethalin; azinphos-methyl) on swimming behaviors, kidney morphology, and expression of nitrotyrosine protein (NTP), dinitrophenyl protein (DNP), superoxide dismutase (SOD), catalase (CAT), renin, and cellular apoptosis in goldfish (Carassius auratus). Results indicated that both low- and high-dose pesticide mixtures decreased the distance swimming behavior. Histological analysis showed pesticide exposure alters kidney morphology. DNP, NTP, and renin expressions, and …
Accelerated Evolution Of Sars-Cov-2 In Free-Ranging White-Tailed Deer, Dillon S. Mcbride, Sofya K. Garushyants, John Franks, Andrew F. Magee, Steven H. Overend, Devra Huey, Amanda M. Williams, Seth A. Faith, Ahmed Kandeil, Sanja Trifkovic, Lance Miller, Trushar Jeevan, Anami Patel, Jacqueline M. Nolting, Michael J. Tonkovich, J. Tyler Genders, Andrew J. Montoney, Kevin Kasnyik, Timothy J. Linder, Sarah N. Bevins, Julianna B. Lenoch, Jeffrey C. Chandler, Thomas J. Deliberto, Eugene V. Koonin, Marc A. Suchard, Philippe Lemey, Richard J. Webby, Martha I. Nelson, Andrew S. Bowman
Accelerated Evolution Of Sars-Cov-2 In Free-Ranging White-Tailed Deer, Dillon S. Mcbride, Sofya K. Garushyants, John Franks, Andrew F. Magee, Steven H. Overend, Devra Huey, Amanda M. Williams, Seth A. Faith, Ahmed Kandeil, Sanja Trifkovic, Lance Miller, Trushar Jeevan, Anami Patel, Jacqueline M. Nolting, Michael J. Tonkovich, J. Tyler Genders, Andrew J. Montoney, Kevin Kasnyik, Timothy J. Linder, Sarah N. Bevins, Julianna B. Lenoch, Jeffrey C. Chandler, Thomas J. Deliberto, Eugene V. Koonin, Marc A. Suchard, Philippe Lemey, Richard J. Webby, Martha I. Nelson, Andrew S. Bowman
United States Department of Agriculture Wildlife Services: Staff Publications
The zoonotic origin of the COVID-19 pandemic virus highlights the need to fill the vast gaps in our knowledge of SARS-CoV-2 ecology and evolution in non-human hosts. Here, we detected that SARS-CoV-2 was introduced from humans into white-tailed deer more than 30 times in Ohio, USA during November 2021-March 2022. Subsequently, deer-to-deer transmission persisted for 2–8 months, disseminating across hundreds of kilometers. Newly developed Bayesian phylogenetic methods quantified how SARS-CoV-2 evolution is not only three-times faster in white-tailed deer compared to the rate observed in humans but also driven by different mutational biases and selection pressures. The long-term effect of …
Analysis Of Mitochondrial Dna Sequence Data Demonstrates That Monophyly Of Myotis Occultus Is Complicated By Greater Sampling Of Myotis Lucifugus, Jeffrey M. Lorch, Daniel R. Taylor, Antoinette J. Piaggio
Analysis Of Mitochondrial Dna Sequence Data Demonstrates That Monophyly Of Myotis Occultus Is Complicated By Greater Sampling Of Myotis Lucifugus, Jeffrey M. Lorch, Daniel R. Taylor, Antoinette J. Piaggio
United States Department of Agriculture Wildlife Services: Staff Publications
Abstract
The validity of Myotis occultus as a species unique from Myotis lucifugus has been a source of debate. Most recently, many authorities treat M. occultus as a distinct species, at least in part because a previous study showed that M. occultus and M. l. carissima (the subspecies that occurs in closest geographic proximity to M. occultus) form separate monophyletic clades based on sequences of two mitochondrial genes (cytochrome-b [cytb] and cytochrome oxidase subunit II [COII]). We re-evaluated the phylogenetic relationship between M. occultus and M. lucifugus based on mitochondrial sequences …
The Distribution And Reproductive Success Of The Western Snowy Plover Along The Central And Southern Oregon Coast - 2023, David J. Lauten, Kathleen A. Castelein, Mary Lee, Jacey Corrente, Marty R. Mccamant, Eleanor P. Gaines
The Distribution And Reproductive Success Of The Western Snowy Plover Along The Central And Southern Oregon Coast - 2023, David J. Lauten, Kathleen A. Castelein, Mary Lee, Jacey Corrente, Marty R. Mccamant, Eleanor P. Gaines
Institute for Natural Resources Publications
We monitored the distribution, abundance and productivity of the federally threatened Western Snowy Plover (Anarhynchus nivosus nivosus) along the central and south coast of Oregon from 4 April – 15 September 2023. We surveyed and monitored plover activity in a project area that included, from north to south, Sutton Beach, Siltcoos River estuary, the Dunes Overlook, North Tahkenitch Creek, Tenmile Creek, Coos Bay North Spit, Bandon Snowy Plover Management Area, New River Habitat Restoration Area (HRA) and adjacent lands, and Floras Lake. Our objectives for the project area in 2023 were to: 1) estimate the size of the adult Snowy …
Unlocking The Mysteries Of Opportunism: Neuroendocrine Insights From An Aseasonal Breeder (Taeniopygia Guttata), Jessica A. Moodie
Unlocking The Mysteries Of Opportunism: Neuroendocrine Insights From An Aseasonal Breeder (Taeniopygia Guttata), Jessica A. Moodie
Graduate Theses and Dissertations (2019 - present)
The regulation of reproductive physiology in animals is mediated by the Hypothalamus-Pituitary-Gonad (HPG) axis. In seasonal breeders, a conserved reciprocal switching of deiodinase enzymes alters thyroid hormone signaling, which controls HPG activity. This study tested the hypothesis that neural regulation of the HPG axis as described in seasonal systems is conserved and repurposed to respond to other cues in aseasonal species. Using water deprivation and nest restriction in the opportunistic Zebra Finch, we were able to create a breeding group and non-breeding group, confirmed by egg laying and changes in ovarian anatomy. Breeding females had clear follicular hierarchy, increased ovary …
Characterization Of Enterovirus D68 In A Mouse Model And Evaluation Of Antiviral Therapies, Zoe K. Taylor
Characterization Of Enterovirus D68 In A Mouse Model And Evaluation Of Antiviral Therapies, Zoe K. Taylor
All Graduate Theses and Dissertations, Fall 2023 to Present
Enterovirus D68 (EV-D68) is a virus that causes respiratory disease. Children are most commonly affected by EV-D68 but immunocompromised adults can also get infected and develop severe disease signs. In 2014, the United States experienced an unprecedented outbreak of EV-D68. Similar outbreaks were also observed in 2016, 2018 and 2022. Interestingly, few EV-D68 infections were observed in 2020, likely due to public health measures put in place to reduce the spread of another respiratory disease, coronavirus disease 2019 (COVID-19). EV-D68 is in the same virus family as polio, and one of the most concerning findings from these outbreaks is that …
Atmospheric Mercury At Storm Peak Laboratory: Development Of Methods To Calibrate Ambient Oxidized Mercury Measurements And Comparisons To A 3-D Photochemical Transport Model, Tyler Raymond Elgiar
Atmospheric Mercury At Storm Peak Laboratory: Development Of Methods To Calibrate Ambient Oxidized Mercury Measurements And Comparisons To A 3-D Photochemical Transport Model, Tyler Raymond Elgiar
All Graduate Theses and Dissertations, Fall 2023 to Present
Mercury (Hg) is a highly toxic metal found ubiquitously throughout the environment that has the potential to harm wildlife and human health. Human exposure to Hg can lead to symptoms such as blindness, loss of memory, ataxia, and death. Hg exposure to pregnant women and young children is of even greater concern, as high levels of Hg can hinder fetal and child development.
Hg is emitted into the atmosphere through natural and anthropogenic processes such as biomass burning and the incineration of coal, respectively. Hg exists in the atmosphere as elemental Hg (Hg0) or in an oxidized form …
Relative Hepatotoxocity, Carcinogenicity, And Toxicogenomics Of Select Dehydropyrrolizidine Alkaloids In Mice, Michael J. Clayton
Relative Hepatotoxocity, Carcinogenicity, And Toxicogenomics Of Select Dehydropyrrolizidine Alkaloids In Mice, Michael J. Clayton
All Graduate Theses and Dissertations, Fall 2023 to Present
Dehydropyrrolizidine alkaloids are arguably the most important plant derived toxins in terms of impact on human and animal health. Dehydropyrrolizidine alkaloids are a large group of chemically related compounds found in 3% of flowering plants worldwide. Human exposure occurs from ingestion of herbal products including teas supplements or contaminated grain. Animals are exposed through contaminated feed or grazing. There are at least 350 identified toxic PAs, from more than 6,000 plants. The toxins primarily cause liver damage, but some are proven to cause cancer. Indidvidual dehydropyrrolizidine alkaloids vary in their toxic effects. Riddelliine is the only dehydropyrrolizidine alkaloid with extensive …
Assessment Of Dietary Energy And Amino Acid Diet Formulation In The Modern Broilers, Matheus Freitas Costa
Assessment Of Dietary Energy And Amino Acid Diet Formulation In The Modern Broilers, Matheus Freitas Costa
Graduate Theses and Dissertations
As a result of the advancement of genetics, understanding broiler requirements for dietary energy and amino acids is essential for improving live performance and carcass characteristics. The energy system used to formulate diets in poultry is based on metabolizable energy (ME); this equation can be described as the total amount of energy in the feed minus gases and feces. However, the net energy (NE) system may be the best depiction of the energy utilized by birds for production and maintenance purposes once the heat increment (HI) is measured. Thus, a series of studies were conducted to establish the responsiveness of …
Determination Of P Availability In Feedstuffs And The Effect Of Feedstuffs And Anti-Nutritional Factors On Secretory Iga Production And Host Nutrient Losses In Poultry, Benjamin Parsons
Graduate Theses and Dissertations
The availability of P in feedstuffs and the effect of feedstuffs, feed additives, and anti-nutritional factors on secretory IgA (sIgA) production in chickens were evaluated. A rapid method was developed using the precision-fed rooster assay to evaluate phytic acid disappearance, P digestibility, and phytase efficacy. Further, exogenous phytase was found to be effective at degrading myo-inositol 1,2,3,4,5,6-hexakis, however, the enzyme was less efficient at P release from lower inositol phosphates. The availability of P in feedstuffs was found to be affected by dietary Ca content, where increasing Ca linearly reduced (P < 0.05) both phytic acid hydrolysis and P digestibility. For example, the standardized ileal digestibility of P was reduced from 73 to 47% in soybean meal when the dietary Ca content was increased from 0.30 to 0.75%. The digestibility of P in distillers dried grains with solubles (DDGS) and corn fermented protein (CFP), however, was high across all Ca levels (71 to 80%). Relative P bioavailability based on tibia bone ash was also found to be high for DDGS and CFP, being 81 and 78%, respectively. Upon further evaluation, it was observed that utilizing low dietary Ca levels (0.30%) when P digestibility in individual plant-based feedstuffs was determined overestimated the P digestibility in practical grower diets by up to 16 percentage units. Utilization of higher Ca levels (0.75%) when P digestibility in individual plant-based feedstuffs was determined, however, resulted in calcualted P digestibility values that were within 1 to 3 percentage units of the measured digestibility in practical grower diets. Aside from P, feedstuffs were also evaluated to determine their effect on sIgA production in the intestine. Roosters excreted approximately 6 to 30 mg of sIgA / 24 h. Further, the proportional contribution of sIgA to total endogenous amino acid (AA) losses ranged from 1 to 13%, with the greatest contribution being observed for Trp. The addition of casein to a protein-free diet increased (P < 0.05) sIgA production in both roosters and broiler chickens. There was no change (P > 0.05) in sIgA production compared with the protein-free diet …
Feed Value And Utilization Of Corn Residue: Implications For Cow Performance And Grazing Strategies, Kaylee E. Wheeler
Feed Value And Utilization Of Corn Residue: Implications For Cow Performance And Grazing Strategies, Kaylee E. Wheeler
Department of Animal Science: Dissertations, Theses, and Student Research
Two experiments were conducted to determine the correlation of corn residue feed value and utilization on cow performance and potential grazing strategies. A qualitative observation of corn residue grazing by 13 cattle herds across Nebraska was conducted over two years. Based on producer reported grain yields and stocking rates, it was found that these producers were generally not as aggressive as the recommended 1.2 animal unit months (AUM) for each 6,280 kg/ha (100 U.S. bushels/acre) of harvested grain. They stocked 17 to 101% of the recommendation and on average used 63% of the carrying capacity. Across herds, average body condition …
Predicting Body Weight Of Cattle And Nutrient Digestion Of Individual Sweet Bran Components To Improve Beef Cattle Production Efficiency, Dalton J. Anderson
Predicting Body Weight Of Cattle And Nutrient Digestion Of Individual Sweet Bran Components To Improve Beef Cattle Production Efficiency, Dalton J. Anderson
Department of Animal Science: Dissertations, Theses, and Student Research
Efficiency is of high importance to beef cattle producers to ensure that beef cattle are being raised without unnecessary resource use. Two separate experiments were conducted to evaluate potential strategies to improve efficiency in beef cattle production. A metabolism study was conducted to evaluate digestion parameters of individual Sweet Bran components. The objective was to determine the effects of diet components on nutrient digestion and rumen fermentation parameters. The individual components of Sweet Bran (Corn bran, solvent-extracted germ meal, and corn steep liquor) were included at 40% diet dry matter (DM) in a steam-flaked corn (SFC) based diet. A SFC-based …
Investigation Of Breeding Objectives And Indexes-In-Retrospect, Hunter F. Valasek
Investigation Of Breeding Objectives And Indexes-In-Retrospect, Hunter F. Valasek
Department of Animal Science: Dissertations, Theses, and Student Research
This thesis presents two projects that investigate the impacts of breeding objectives and indexes-in-retrospect within the beef cattle industry. The first project synthesized how changes due to planning horizon, breeding system, and sale endpoint in the economic breeding goal of cattle influence the relative emphasis of traits as well as the re-ranking of selection candidates. A total of three breeding systems that represent straightbred and crossbred cattle were used along with six planning horizons (2, 5, 10, 20, 30, and 50 yrs.) for both a weaning and slaughter point of sale. The combination of these different breeding objective attributes resulted …
The Evaluation Of Feed Additives On Reducing Enteric Methane Production From Cattle, Reba L. Colin
The Evaluation Of Feed Additives On Reducing Enteric Methane Production From Cattle, Reba L. Colin
Department of Animal Science: Dissertations, Theses, and Student Research
Environmental sustainability can be positively impacted by the inclusion of feed additives to reduce enteric methane production from cattle. Methane production can be affected by feed additives that either alter the rumen environment or act as methanogenesis inhibitors. A reduction in methane from cattle can contribute to meeting carbon neutrality.
A metabolism study was conducted to evaluate Alga 1.0, a product containing bromoform, fed to cattle to evaluate the effects on gas emissions. Treatments were (0, 69, or 103 g/d Alga 1.0) fed in a corn-based diet. Headbox-style indirect calorimeters were used to measure gas emissions. Feeding Alga 1.0 linearly …
The Impact Of Silage Inclusion In Diets With Different Corn Processing And The Effect Of Natural And Conventional Feeding Programs On Finishing Cattle Performance, Jessica L. Miller
The Impact Of Silage Inclusion In Diets With Different Corn Processing And The Effect Of Natural And Conventional Feeding Programs On Finishing Cattle Performance, Jessica L. Miller
Department of Animal Science: Dissertations, Theses, and Student Research
A finishing experiment was conducted to determine the effects of natural and conventional feeding programs on finishing performance of steers and heifers. Factors were conventional and natural feeding programs in steers and heifers. Cattle assigned to the conventional program were fed diets that contained Rumensin (Elanco Animal Health), Tylan (Elanco Animal Health), MGA (Zoetis), and received growth promoting implants whereas cattle in the natural program received neither. Compared to natural fed cattle, G:F was improved by 15.5% when heifers were fed in a conventional program (P < 0.01) and 23.8% when steers were fed in a conventional program (P < 0.01). The incorporation of implants and feed additives within the finishing period increased …