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The Influence Of Researcher Disturbance On Raccoon Predation Of American Alligator Nests, Clarissa Tuten May 2024

The Influence Of Researcher Disturbance On Raccoon Predation Of American Alligator Nests, Clarissa Tuten

Electronic Theses and Dissertations

Raccoons (Procyon lotor) are a dominant predator of American alligator (Alligator mississippiensis) nests in the southeastern United States, using a combination of olfactory, visual, and tactile cues to identify nest locations. Studies on alligator nesting ecology typically require researchers to create paths through marsh habitat, potentially introducing visual and olfactory cues raccoons may use to locate nests. The purpose of this study was to evaluate the effect of human visitation to alligator nests on the frequency of raccoon nest predation at two sites in coastal South Carolina, Tom Yawkey Wildlife Center (TYWC) and Santee Coastal Reserve (SCR). We hypothesized that …


Valuation Of Soybean Meal Versus Distillers Co-Products As A Protein Supplement For Finishing Beef Cattle: Effects On Growth Performance, Carcass Characteristics, And Efficiency Of Dietary Net Energy Utilization, Cassidy R. Ross Jan 2024

Valuation Of Soybean Meal Versus Distillers Co-Products As A Protein Supplement For Finishing Beef Cattle: Effects On Growth Performance, Carcass Characteristics, And Efficiency Of Dietary Net Energy Utilization, Cassidy R. Ross

Electronic Theses and Dissertations

Two randomized complete block design experiments were conducted to: 1) examine the effects of soybean meal with or without additional soybean hulls in replacement of modified corn distillers grains plus (MDGS) solubles on growth performance efficiency of dietary net energy utilization and carcass traits responses in finishing beef steers, 2) determine if partial or complete replacement of dried distillers grains plus solubles (DDGS) with solvent-extracted soybean meal (SBM) in diets based upon high-moisture ensiled corn influences growth performance, efficiency of dietary net energy utilization, sera urea-N (SUN) concentrations, or carcass traits in finishing beef steers. Experiment 1 was a 118-d …


Evaluation Of Dietary Fiber Technologies In Sow Diets, Garrin Shipman Jan 2024

Evaluation Of Dietary Fiber Technologies In Sow Diets, Garrin Shipman

Electronic Theses and Dissertations

Various technologies and alternative ingredients are being developed to increase the nutrient value of fibrous feedstuffs, improve animal performance, and promote sustainable swine production. Fiber-degrading enzymes have been extensively studied in growing pigs, with few studies focused on gestating sows. When considering gestating sows have greater energy digestibility of fibrous feedstuffs than grower pigs, the efficacy of fiber-degrading enzymes needs to be determined for implementation in commercial sow diets. As fiber inclusion in gestation diets benefits sow performance, corn dried distiller grains with solubles (DDGS) are a candidate fiber source for gestation alternative energy ingredient. Functional fibers, such as yeast …


Influence Of Reduced Salt In Fully Cooked Ham And Sausage Cured With Natural Celery Powder On The Growth Of Listeria Monocytogenes At 4⁰C, Anne Sherod Jan 2024

Influence Of Reduced Salt In Fully Cooked Ham And Sausage Cured With Natural Celery Powder On The Growth Of Listeria Monocytogenes At 4⁰C, Anne Sherod

Electronic Theses and Dissertations

This research evaluated the influence of reducing salt on outgrowth of L. monocytogenes on ready to eat (RTE) deli-style sliced ham cured with natural celery powder, fully cooked sausage links cured with traditional sodium nitrite and sausage links cured with natural celery powder, vacuum packaged and stored at 4⁰C on the outgrowth of L. monocytogenes. Experiment 1 evaluated L. monocytogenes outgrowth on ham over 153 days on the following treatments, current retail ham (HC) 2.0% salt; reduced salt 1 (HRS1) 1.5% salt; reduced salt 2 (HSR2) 1.35% salt; and reduced salt 2 without antimicrobials (HRS2WA) 1.35% salt without potassium lactate …


Longevity In Afrikaner Cattle: A Survival Analysis, Allison M. Bot Steffl Jan 2024

Longevity In Afrikaner Cattle: A Survival Analysis, Allison M. Bot Steffl

Electronic Theses and Dissertations

The Afrikaner breed of cattle is indigenous to South Africa and due to their hardiness was once the most popular breed amongst farmers. The objectives for this study were to: (1) estimate environmental effects (age at first calving, season) and (2) genetic variance affecting longevity in Afrikaner cattle using survival analysis and a Weibull model and (3) evaluate the effect of the Infusion Project on longevity utilizing a Cox model. For the first objective, age at first calving impacted longevity as younger age at first calving was associated with decreased longevity. Season of birth and year of birth also impacted …


Unbridled Insights: Exploring Equine Behavior Through Gps Tracking And Analysis, Madison L. Philbrick Dec 2023

Unbridled Insights: Exploring Equine Behavior Through Gps Tracking And Analysis, Madison L. Philbrick

Electronic Theses and Dissertations

Horse behavior in pasture and grazing environments remains understudied, despite the substantial domestic horse population in the United States. This paper explores the utilization of Global Positioning System (GPS) technology to detect equine behavior, specifically focusing on grazing behaviors. By analyzing GPS data from (n=9) Standardbred horses, this study aims to establish the capabilities and accuracy of the Columbus P-1 data logger as a low-cost GPs unit for equine research, without the use of accelerometers. Through the data provided by the GPS unit, a model to distinguish grazing, resting, drinking, walking, trotting, and running was developed with satisfactory detection rates. …


Assessing The Role Of The Microbiome, Parasite Infections, And Movement In Avian Health, Olivia N. Choi Dec 2023

Assessing The Role Of The Microbiome, Parasite Infections, And Movement In Avian Health, Olivia N. Choi

Electronic Theses and Dissertations

Avian health encompasses the physical, physiological, and behavioral well-being of birds. Assessing avian health is not only important for the conservation and management of wild birds and the recreational economy, but also for the management of infectious diseases that threaten public health and agriculture. Birds, comprising approximately 10,000 species and an estimated 50 billion individuals worldwide, are known to be involved in the spread of pathogens, some of which are zoonotic (from animals to humans), such as avian influenza and West Nile viruses. Individual measures of avian health may include physical measurements (e.g., body mass, wing length), pathogen infection status, …


Effects Of Wilting Extent On The Phytoestrogen Levels, Nutritional Value, Microbial Populations, And In Vitro Ruminal Methane Emissions Of Red Clover Hay And Silage Across Stages, Diego Zamudio Ayala Aug 2023

Effects Of Wilting Extent On The Phytoestrogen Levels, Nutritional Value, Microbial Populations, And In Vitro Ruminal Methane Emissions Of Red Clover Hay And Silage Across Stages, Diego Zamudio Ayala

Electronic Theses and Dissertations

The main objective of this thesis is to improve the understanding and awareness of methodologies to decrease phytoestrogens in conserved legumes without sacrificing forage nutritive value. In chapter 1, we discussed the main factors influencing each stage of hay production and our current understanding of the hay microbiome dynamics. The primary objective of haymaking is to dry forage enough (80-85% DM) to inhibit the growth of undesirable microbes and halt residual plant enzymatic activity that causes nutrient losses. During the field and storage phases of haymaking, the environment, management practices, and other factors influence the extent of DM losses. This …


Collaborative And Engaged Research To Strengthen Equity And Adaptive Governance In Co-Managed Fisheries, Gabrielle V. Hillyer Aug 2023

Collaborative And Engaged Research To Strengthen Equity And Adaptive Governance In Co-Managed Fisheries, Gabrielle V. Hillyer

Electronic Theses and Dissertations

Small-scale, co-managed fisheries are found throughout the world and often represent intertwining cultures, societies, communities, economies, institutions, and governments. They face complex issues, derived from ecological and social sources. Solving these issues requires diverse expertise, often developed through engaged methodologies which can facilitate collaborative solution creation between researchers, community members, and others. In this dissertation, I demonstrate the benefits of these engaged methodologies and review how they, when coupled with anticolonial approaches to research, can create more equitable solutions to complex issues. This dissertation focuses on multiple projects within the wild clam fishery in Maine including: (1) the creation of …


New Species Of Dryolestoid From The Late Cretaceous Allen Formation And Implications For South American Faunal Diversity., Brigid Erin Connelly Aug 2023

New Species Of Dryolestoid From The Late Cretaceous Allen Formation And Implications For South American Faunal Diversity., Brigid Erin Connelly

Electronic Theses and Dissertations

Dryolestoids are extinct cladotherians mammals from the Jurassic and Cretaceous periods. I describe a collection of dryolestoid specimens from the Late Cretaceous localities of Cerro Tortuga (Allen Formation), Anfiteatro 1, and Shining (both La Colonia Formation) from Patagonia, Argentina. Using comparative morphology, I identify a new species of meridiolestidan dryolestoid based on eleven specimens across both formations. The new species’ recovery from La Colonia Formation represents the first dryolestoid connection between the two approximately contemporaneous formations. The species’ morphology may represent an ecological shift within Meridiolestida from insectivory to herbivory, showing a transition in characters between the plesiomorphic sharp-toothed meridiolestidans …


An Exploration Of Palauan Fishing Methods And Fisheries: A Study For The Conservation Of Dugongs, Mia Glover Jun 2023

An Exploration Of Palauan Fishing Methods And Fisheries: A Study For The Conservation Of Dugongs, Mia Glover

Electronic Theses and Dissertations

The dugong (Dugong dugon) is an important marine mammal in Palau. However, current population dynamics are not well understood. This study aimed to connect scientific data with local knowledge by examining the social implications of changing fishing methods and their impact on dugong population dynamics in the face of climate change and fisheries commercialization. Through interviews with local fishers, it was found that destructive fishing methods like trawling and long lining have led to habitat loss and degradation for dugongs. These tactics, driven by economic factors, have disrupted the delicate balance between human activities and the preservation of dugong habitats, …


Detecting Native Freshwater Mussels In Pennsylvania Waterways: Comparison & Validation Of Environmental Dna Methods, Meredith Bennett May 2023

Detecting Native Freshwater Mussels In Pennsylvania Waterways: Comparison & Validation Of Environmental Dna Methods, Meredith Bennett

Electronic Theses and Dissertations

North America is home to approximately one third of the world's freshwater mussel species. They are highly imperiled organisms due to habitat destruction and invasive species. Traditional surveys rely on visual identification of mussels, but individuals tend to be rare and difficult to identify. An alternative method is to extract environmental DNA (eDNA) from water samples, which has advantages over traditional sampling, including less sampling effort and fewer hazards to researchers and organisms. We conducted a review of the two main eDNA approaches: single-species detection and metabarcoding. We also developed and validated metabarcoding primers for the detection of native mussels. …


Biophysical Factors Impacting Sea Lice Settlement And Survival, Eleanor R. Glahn May 2023

Biophysical Factors Impacting Sea Lice Settlement And Survival, Eleanor R. Glahn

Electronic Theses and Dissertations

Atlantic salmon (Salmo salar L.) aquaculture production in Maine is a valuable contributor to the economy, the expansion of which has been challenged by the parasitic salmon louse Lepeophtheirus salmonis. As planktonic organisms, the life of the salmon louse is primarily dictated by the physical conditions of the environment: the temperature for development time, salinity for survival, and current velocity for transport. Salmon lice are obligate parasites for whom the successful infection of a suitable host is critical to completion of their life cycle. However, little is understood about the effects of current velocity on infection success. Hydrodynamic …


Comparative Energetics Of Mammalian Thermoregulatory Physiology, Ana M. Breit May 2023

Comparative Energetics Of Mammalian Thermoregulatory Physiology, Ana M. Breit

Electronic Theses and Dissertations

Endothermy allows species to decouple body temperature from environmental
temperatures but does not equate to endothermic species maintaining those constant temperatures. Instead, heterothermy fluctuating body temperatures, both in and outside of torpor is common and allows endotherms to expand the limits of thermoneutrality. Thermolability is likely to be more common in the tropics and subtropics, where species live within or above their thermoneutral zone. My dissertation research focused on the heterothermic-homeothermic continuum, specifically quantifying where on the continuum different species fall at certain times and why those species have evolved to be at those points. I quantified the thermal profile …


Optimizing Strategies To Hydraulically Plant Atlantic Salmon Eggs Based On Fry Dispersal Patterns, Ernest J. Atkinson May 2023

Optimizing Strategies To Hydraulically Plant Atlantic Salmon Eggs Based On Fry Dispersal Patterns, Ernest J. Atkinson

Electronic Theses and Dissertations

The Gulf of Maine Distinct Population Segment of Atlantic Salmon has suffered from habitat loss and exploitation over the last century. Hatchery supplementation has prevented the extirpation of the species, but stocking methods represent tradeoffs between survival, domestication, and logistics. Egg planting, the use of eyed embryos, maximizes natural rearing opportunities which can be important for adaptation. This method, however, is logistically demanding and requires significant labor over large spatial, but short temporal, scales dictated by the ontogeny of the fish. However, the survival and dispersal behavior of Atlantic Salmon fry immediately after emergence from eggs planted in artificial nests …


Post-Harvest Treatment Effects On Physicochemical Quality Attributes Of North Atlantic Squid Doryteuthis Pealeii And Illex Illecebrosus, Caitlin M. Hillery May 2023

Post-Harvest Treatment Effects On Physicochemical Quality Attributes Of North Atlantic Squid Doryteuthis Pealeii And Illex Illecebrosus, Caitlin M. Hillery

Electronic Theses and Dissertations

Doryteuthis pealeii (longfin inshore squid) and Illex illecebrosus (Northern shortfin squid) are the two most commercially important species of squid harvested in the United States. They are also the only two species of squid in the world certified sustainable by the Marine Stewardship Council. Despite their pivotal role in the U.S. seafood industry, very little research has been performed on their quality in decades. Two common methods of freezing and secondary processing applied to squid in the U.S. industry are blast-freezing either at sea or on land; and leaving the squid whole, or fully cleaning and then brining them. To …


Evaluation Of Yeast Postbiotic In Sow Diets On Sow And Offspring Performance And Microbial Succession, Joel Kieser Jan 2023

Evaluation Of Yeast Postbiotic In Sow Diets On Sow And Offspring Performance And Microbial Succession, Joel Kieser

Electronic Theses and Dissertations

Litter size and the resulting nutritional demand on the sow continue to increase while sow mortality and culling rate are also increasing. Non-nutritive feed additives may enhance sow health and thereby improve offspring growth and productivity after weaning. Development of the gut microbiome in piglets via microbial succession is critical for maximizing their productivity and providing stability for overcoming weaning stress. The objective of this study was to evaluate the impact of yeast-based postbiotic supplementation in gestation and lactation diets on offspring performance through the nursery period and on whether a yeast postbiotic could impact the sow fecal microbiome as …


In-Vivo Assessment Of A Direct-Fed Microbial On Lactation Performances, Blood Biomarkers, Ruminal Fermentation And Microbial Abundance In Transition To Mid-Lactation Holstein Cows, Marcela Bulnes Lopez Jan 2023

In-Vivo Assessment Of A Direct-Fed Microbial On Lactation Performances, Blood Biomarkers, Ruminal Fermentation And Microbial Abundance In Transition To Mid-Lactation Holstein Cows, Marcela Bulnes Lopez

Electronic Theses and Dissertations

The transition period is a crucial stage in the lactation cycle and can lead to significant metabolic changes in cows. The use of nutritional interventions, such as direct-fed microbials, may assist cows during the transition from pregnancy to early lactation, reducing the occurrence of metabolic disorders and improving overall health. The primary goal of this study was to assess the effects of a commercial rumen-derived directfed microbial (DFM) product (Galaxis™ Frontier (GF) Native Microbials Inc., CA, USA) on various factors such as performance, blood biomarkers, rumen fermentation, and bacterial population in dairy cows during the transition period up to 100 …


Regional Assessment Of Live Cattle And Carcass Characteristics In The Northern Plains, Harlee A. Brauckmuller Jan 2023

Regional Assessment Of Live Cattle And Carcass Characteristics In The Northern Plains, Harlee A. Brauckmuller

Electronic Theses and Dissertations

The goal of this project was to perform a regional assessment of live cattle and carcass characteristics in the northern plains. The assessment audited three packing plants to assess fed cattle, cow, and bull production. The live animal factors evaluated were transportation, mobility of cattle, identification, brands, and mud/manure present. Data collected during the slaughter process was bruising, dentition, and offal condemnations. In fed cattle yield grade, quality grade, and hot carcass weight were assessed. In cows and bulls muscle score and fat color score were assessed. To assess differences between cattle in the Northern Plains and cattle in the …


Characterizing Vaginal Gene Expression In Prepubertal Gilts, Shannon Lee Dierking Jan 2023

Characterizing Vaginal Gene Expression In Prepubertal Gilts, Shannon Lee Dierking

Electronic Theses and Dissertations

The best-known predictor of reproductive success in gilts is the age at puberty. Early puberty (i.e., d170 – d180 of age) is associated with improved long-term reproductive performance and more full value offspring for market. The ability to predict, in the prepubertal stage, the age that a replacement gilt would be expected to achieve puberty has great reproductive and economic advantages. This work focuses on identifying biological markers that are potentially predictive of age at puberty. Study 1 identified changes in the vaginal epithelium during gilt reproductive development. Pre-pubertal gilts (n =13) were followed from d70 of age until first …


Evaluation Of Feed Additives And Delivery Method For Receiving And Finishing Cattle, Thiago Lauro Maia Ribeiro Jan 2023

Evaluation Of Feed Additives And Delivery Method For Receiving And Finishing Cattle, Thiago Lauro Maia Ribeiro

Electronic Theses and Dissertations

Trace minerals (TM) and vitamins are essential to improve production output and efficiency in beef cattle. The first experiment was conducted to investigate if the delivery method of TM and Saccharomyces cerevisiae yeast culture influence growth performance and hepatic TM content of receiving steers. The second experiment evaluated the effect of supplemental protected B - vitamins to finishing steers. Experiment 1 used Charolais x Angus steers calves (n = 192; 256 ± 14 kg) in a 49-d receiving experiment. Within 36h of weaning, steers were weighed, allotted to 24 pens (n = 8 steers/pen; 8 pens/treatment) and randomly assigned to …


Physically Adjusted Neutral Detergent Fiber System: Effects Of Dextrose And Non-Forage Fiber On Performance, Feeding Behavior, Digestibility, Rumen Fermentation And Rumen Bacterial Abundance In Dairy Cattle, Jorge Luis Bonilla Urbina Jan 2023

Physically Adjusted Neutral Detergent Fiber System: Effects Of Dextrose And Non-Forage Fiber On Performance, Feeding Behavior, Digestibility, Rumen Fermentation And Rumen Bacterial Abundance In Dairy Cattle, Jorge Luis Bonilla Urbina

Electronic Theses and Dissertations

The newly proposed physically adjusted NDF system (paNDF) system aims to maintain a favorable rumen environment (e.g., pH) by taking into account both the physical and chemical composition of diet. Thus, the objective of this study was to determine the effects of water-soluble carbohydrates (WSC) and non-forage NDF inclusion in a paNDF system on production performance, rumen pH and fermentation profile, rumen bacterial abundance, feeding behavior and nutrient digestibility in late-lactating Holstein cows. Nine fistulated multiparous Holstein cows (2nd and 3rd parity) were used in a triplicated 3×3 Latin Square experiment. Each period lasted for 21 d with 14 d …


Strategies To Optimize Confinement Fed Beef Cattle In The Northern Plains, Erin R. Gubbels Jan 2023

Strategies To Optimize Confinement Fed Beef Cattle In The Northern Plains, Erin R. Gubbels

Electronic Theses and Dissertations

The goal of this dissertation was to understand the strategies needed to optimize performance of confinement fed beef cattle in the Northern Plains. This was accomplished through three objectives: 1) evaluate health, growth performance, and antibody titers in previously vaccinated, newly weaned calves administered a respiratory and clostridia vaccine upon arrival compared to no vaccination; 2) determine the influence of manger space restriction on program-fed feedlot heifers during the growing phase; and 3) to evaluate growth performance and carcass traits following transit of feedlot heifers sourced and finished in different regions of the United States. For objective 1, single-sourced, newly …


Walleye Feeding, Movements, And Energetics Reveal The Importance Of Connected Wetlands In Glacial Lakes, Logan M. Cutler Jan 2023

Walleye Feeding, Movements, And Energetics Reveal The Importance Of Connected Wetlands In Glacial Lakes, Logan M. Cutler

Electronic Theses and Dissertations

Fish require a variety of resources including prey, thermal refugia, and different physical habitat characteristics to grow and reproduce. All necessary resources are rarely provided by a single habitat, resulting in tradeoffs between occupying different habitats; therefore, the ability to move among heterogenous habitats is critical. These tradeoffs may occur in lakes with connected wetlands where the main lake habitats tend to be more thermally stable, but wetlands often provide more diverse and abundant prey. For my second chapter, I compared prey diversity and abundance as well as Walleye (Sander vitreus) diets and condition in a large glacial lake (Lake …


The Effects Of Body Weight, Feed Intake, And Weather On Total And Liquid Water Intake In Growing Beef Cattle, Madison Rae Kovarna Jan 2023

The Effects Of Body Weight, Feed Intake, And Weather On Total And Liquid Water Intake In Growing Beef Cattle, Madison Rae Kovarna

Electronic Theses and Dissertations

Research conducted in the 1950s to determine water requirements utilized cattle that vary greatly from the animals being raised today. Additionally, most of the previous research has been conducted on animals being fed for slaughter, rather than bulls or reproductive females. The objective of this study was to analyze the effect of weather variables, dry matter intake (DMI), and body weight (BW) on total daily water intake (TDWI) and liquid daily water intake (LDWI) in growing beef bulls and heifers. Two contemporary groups of Angus and Simmental x Angus bulls and heifers over a two-year period were utilized in this …


Evaluation Of Precision Ingredient Inclusion On Production Efficiency Responses In Finishing Beef Cattle, Santana R. Hanson Jan 2023

Evaluation Of Precision Ingredient Inclusion On Production Efficiency Responses In Finishing Beef Cattle, Santana R. Hanson

Electronic Theses and Dissertations

Two randomized complete block design feedlot experiments were conducted over the course of two years. These experiments were conducted to investigate the effects of 1) evaluate the observed-to-expected ratio for ingredient inclusion using no commodity inclusion assistance technology or using commodity inclusion assistance technology; and 2) evaluate the influence that varying degrees (highly variable at random or 0.454 kg asfed tolerance for each ingredient) of accuracy on ingredient inclusion have on growth performance, carcass traits, efficiency of dietary NE utilization, and ingredient inventory management in finishing beef cattle. Experiment 1 used single source Black Angus heifers (n = 60; initial …


Relating Predator Community Ecology And Duck Nest Survival In Eastern South Dakota, Samantha R. Fino Jan 2023

Relating Predator Community Ecology And Duck Nest Survival In Eastern South Dakota, Samantha R. Fino

Electronic Theses and Dissertations

As conversion of native grasslands and wetlands to croplands continues in the Prairie Pothole Region (PPR), managers are tasked with maintaining sustainable waterfowl populations. Mesopredator community dynamics is a hypothesized mechanism driving spatiotemporal variation of waterfowl nest survival in the PPR, yet studies often lack detailed information on mesopredator species occurrence and abundance. Therefore, understanding spatial and temporal variation in behaviors of mesopredators provides valuable insights for understanding predator-prey interactions between mesopredators and upland duck nests. Further, differences in a predator community resulting from lethal removal of dominant species may influence composition and space use patterns of subordinate and non-target …


Impact Of Virtual Fence Technology On Yearling Steer Behavior, Performance, And Energetic Expenditure, Logan Riley Vandermark Jan 2023

Impact Of Virtual Fence Technology On Yearling Steer Behavior, Performance, And Energetic Expenditure, Logan Riley Vandermark

Electronic Theses and Dissertations

Beef cattle production in the U.S. is largely dependent upon extensive rangelands like the Northern Great Plains. Solutions are needed to meet both the demand of animal-based protein products for a growing world population and the desire for producers to manage for several different ecosystem functions. Virtual fencing (VF) is an emerging precision technology that has the potential to revolutionize livestock management on extensive rangeland systems. However, the need to quantify animal behavior and performance differences using emerging precision technologies, like VenceTM, is ever growing. Thus, the objective of this research was to determine the impact of virtual fencing on …


Effects Of Dietary Genistein And Fugacity Modelling In An Aquaculture System, Travis Schaeffer Jan 2023

Effects Of Dietary Genistein And Fugacity Modelling In An Aquaculture System, Travis Schaeffer

Electronic Theses and Dissertations

Fish production from aquaculture has continued to grow over the past several decades, with finfishes being fed formulated, fish meal-based diets supporting most of that industry’s growth. However, increased demand and costs, coupled with static volume and erratic supplies of fish meal, has resulted in the use of alternative plant-derived protein sources. A common oilseed protein source is soybean meal (SBM), because of its protein content and amino acid profile; however, it also contains multiple anti-nutritional factors, including phytoestrogens. Phytoestrogens are naturally produced, estrogenmimicking compounds, with isoflavones receiving the most investigation as higher levels of these compounds occur within SBM. …


Effect Of Lighter (273 Kg) And Heavier (356 Kg) Initial Weight On Growth Performance Of Single-Source, Pre-Conditioned Beef Steers Fed A Single Growing-Finishing Diet, Thomas C. Norman Jan 2023

Effect Of Lighter (273 Kg) And Heavier (356 Kg) Initial Weight On Growth Performance Of Single-Source, Pre-Conditioned Beef Steers Fed A Single Growing-Finishing Diet, Thomas C. Norman

Electronic Theses and Dissertations

The objective of the study was to determine the influence that initial BW has on growth performance responses, efficiency of dietary net energy (NE) utilization, and carcass traits in feedlot steers. Light- and heavy-weight Charolais×Red Angus steers (n = 70) selected from a larger single-source group were used in a 209-d growing-finishing feedlot experiment at the Ruminant Nutrition Center, in Brookings, SD. On d-0 and d-1 weight and hip height (HH) measurements were collected for allotment purposes; the initial experimental weight was the average between d 0 and d 1 BW. Steers were assigned to two groups based on initial …