Physiology Commons^™

Health Indicators Worsened By Moderate-Intensity Heat Stress Are Only Partially Recovered By Ω-3 Polyunsaturated Fatty Acid Supplementation, Melanie R. White, Shelley A. Curry, Ashley A. Hahn, Jessica L. Petersen, Ty B. Schmidt, Dustin T. Yates

Nebraska Beef Cattle Reports

Summary with Implications

Heat stress throughout the summer and into the fall is a persistent hurdle for growing and finishing cattle in Nebraska. Minimizing the impact of heat on growth and well-being of cattle is critical to the productivity and profitability of beef production. This project aimed to evaluate the effect of an anti-inflammatory dietary supplement, ω-3 polyunsaturated fatty acids (ω-3 PUFA), on physiological indicators of stress during a 4-day moderate-intensity heat challenge. Heat stress elevated core body temperature and respiration rates as expected but did not impact circulating inflammatory biomarkers. Heart rate variability measurements indicative of adrenergic stress and …

Modulation Of Heat Stress Responses In Cattle Supplemented With Dietary Ω-3 Polyunsaturated Fatty Acids, Shelley A. Curry, Melanie R. White, Ashley A. Hahn, Dustin T. Yates

Nebraska Beef Cattle Reports

Summary with Implications

Heat stress in beef cattle triggers physiological and metabolic disturbances that compromise performance, health, and welfare. In this study, Red Angus heifers exposed to heat stress for 5 days exhibited elevated body temperatures, increased heart and respiration rates, and altered hematological and acid–base parameters. A commercial ω-3 polyunsaturated fatty acid (PUFA) dietary supplement failed to improve heat stress-reduced ribeye area or red blood cell parameters but did resolve the reduction in blood chloride concentrations, which is consistent with restoration of electrolyte balance and hydration under heat stressed conditions. These results indicate that ω-3 PUFA supplementation offers some …

Implications Of Type Iv Pilus Retraction For Dna Uptake By Acinetobacter Baumannii, Yafan Yu

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Horizontal gene transfer (HGT) via natural competence allows bacteria to incorporate extracellular DNA (eDNA) into their genomes, facilitating genetic diversity and adaptation. In Acinetobacter species, natural competence depends on DNA binding and uptake mediated by type IV pili (T4P). T4P are dynamic extracellular filaments composed primarily of the major pilin subunit PilA, along with a few minor subunits. T4P drive a range of cellular functions including twitching motility, biofilm formation, and DNA uptake, with some functions dependent on pilus retraction and others not. However, how Acinetobacter T4P bind DNA and how T4P/eDNA interactions impact biofilm formation remain unclear. Here, I …

Contraceptive Hormone Influences On The Role Of Primary Reinforcement And Reinforcer-Enhancement In Nicotine Self-Administration, Kathleen Robin Mcnealy

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Hormonal contraceptives contain a synthetic estrogen (e.g., ethinyl estradiol/EE) and/or a synthetic progestin (e.g., levonorgestrel/LEVO) and can exacerbate nicotine intake. However, whether altered intake reflects changes in nicotine reinforcement or enhancement by nicotine of co-occurring reinforcers is unknown. This reinforcer-enhancement effect is evidenced in rats when nicotine self-administration is increased by the presence of a visual stimulus (VS) reinforcer. This dissertation examined the effects of EE and LEVO on nicotine reinforcement and reinforcer-enhancement in ovary-intact female Sprague-Dawley rats. Rats were implanted with a jugular catheter and assigned to receive daily injections of EE (Vehicle, 0.125 [Low], or 0.18 [High] μg/day; …

Sarcopenia And The Importance Of Resistance Training And Protein-Rich Diets For Prevention Of Muscle Loss In Older Adults: A Literature Review And Informational Pamphlet, Madison Steele

Honors Program: Senior Projects (Public)

The growing prevalence of sarcopenia among older adults as well as youths has prompted further research aimed at developing effective preventative measures and treatment plans. Sarcopenia is often thought to occur solely due to aging, but several other factors contribute to progressive muscle loss. Previous research studies have found an effect of physical activity and dietary protein levels on the risk of developing sarcopenia as well as its onset age. This study aims to review existing knowledge in the field to compile an extensive list of sarcopenia causes and methods of prevention. The main causes identified in this review are …

Artificial Insemination And Fetal Programming In Beef Production Systems, Dempster M. Christenson

Department of Animal Science: Dissertations, Theses, and Student Research

Pregnancy to artificial insemination and late gestation fetal programming of the next calf crop are central to genetic development, reproductive longevity, calf crop productivity, and efficiency of cow/calf ranching. The purposes of this research are to find methods to improve pregnancy rate to artificial insemination, the growth and reproductive health of pregnant heifers, and the productivity of their offspring. In the first of four studies we found that extending the period of progesterone administration in an estrus synchronization protocol did not significantly hasten estrus response or increase pregnancy rate to artificial insemination, but timing of estrus within the melengestrol acetate …

Mid-Gestation Maternofetal Inflammation Impacts Growth, Skeletal Muscle Glucose Metabolism, And Inflammatory Tone In The Ovine Fetus During Late Gestation, Zena Mariah Hicks

Department of Animal Science: Dissertations, Theses, and Student Research

Our 1^st and 2^nd studies assessed the impact of mid-gestation maternofetal inflammation on growth, skeletal muscle glucose metabolism, and inflammatory tone in the late gestation ovine fetus. The objective was to determine if inducing maternofetal inflammation during peak placental growth would lead to more profound IUGR characteristics in the fetus. MI-IUGR fetuses exhibited reduced body and skeletal muscle weights and hallmark asymmetric growth at late gestations. Fetuses had higher baseline glucose:insulin ratios and reduced glucose-stimulated insulin secretion. Moreover, hindlimb glucose oxidation was impaired independent of glucose uptake. Skeletal muscle specific glucose uptake and oxidation was reduced in MI-IUGR …

A Look Into The Physiological Impacts Of Childhood Cancers And Modeling Of Tumor Growth Rate, Erica Steiner, Kimberly Hansen, Marissa Stanton

Honors Program: Senior Projects (Public)

Cancer is one of the deadliest diseases present in the world. Children have different reactions to diseases and treatments; thus, it is important to study those reactions specifically in children. Knowing how children are impacted by these factors can be helpful in diagnosis and treatment of cancer. I performed this study by researching the different types of cancer I was interested in and using MATLAB to code for and simulate a growth curve of a brain tumor. I found that there are many different physiological impacts of different cancers in children. As for the modeling, I was able to get …

Monarch Butterflies: Rearing Methodologies And The Impact Of Fungicide And Insecticide Exposures, Matthew Greiner

Department of Entomology: Dissertations, Theses, and Student Research

The North American migratory monarch butterfly, Danaus plexippus L., populations has experienced a ca. 90% decline over the past two decades. The decline is attributed to climate change, loss and degradation of overwintering habitat, and the loss of milkweed plants in the midwestern United States. The remaining milkweed stands often occur close to agricultural fields, and efforts to establish additional milkweed on the landscape focus on agricultural systems. However, milkweed plants near agricultural fields are likely exposed to pesticides that could adversely impact monarch caterpillars. Effective management of milkweed habitat supporting monarch caterpillars requires knowledge about the toxicological impacts of …

Supplemental Peer Instruction In Physiologic Core Concept Education, Austin Choat

Honors Program: Senior Projects (Public)

The objective of my thesis project was to create and research the importance of supplemental learning videos within core physiological concepts identified by the Advancement of Physiological Principles for the purpose of assisting Dr. Kim Hansen in better educating students with less extensive foundational knowledge of chemical and biological sciences. Through researching the benefits of peer instruction, identifying core physiological concepts crucial to wholistic physiology education, and describing a student population hypothesized to benefit substantially from the work, I created educational videos to aid Dr. Hansen in her work as an educator and in the educational research she is striving …

James Davidson Fawcett (1933–2020): Imbibing With The Kiwi, Louis A. Somma

Papers in Herpetology

An obituary and summary of the life of James D. Fawcett (1933-2020), herpetologist and instructor and professor of Biology at University of Nebraska at Omaha, 1972-2015. Includes bibliography of his works, list of master's theses chaired, and recollections of former students.

A Kinesiological Analysis Of Dancers At The University Of Nebraska-Lincoln, Vanessa Reiser

Honors Program: Senior Projects (Public)

Supplemental conditioning can improve a dancer’s performance of important skills without taking away from class and rehearsal time. To investigate this further, an individualized conditioning plan based on a specific skill was created for eight student dancers, and the effects were analyzed using a survey and rating scale by a trained dance professor. The results showed improvement of skills for the majority of dancers, along with improved fitness in qualities such as strength and balance. In conclusion, individualized conditioning plans based on a specific skill may benefit student dancers who are juggling intense class and rehearsal schedules.

Characterization Of A Split-Nluc Assay For Monitoring Changes In Alpha-Synuclein Solubility In Living Cells, Baolong Truong

Honors Program: Senior Projects (Public)

Alpha-synuclein is the primary constituent of Lewy Bodies, protein aggregates associated with Parkinson’s Disease, Dementia with Lewy Bodies, and Multiple Systems Dystrophy. Given the terminal nature of these synucleinopathies, the need for an assay that can report on alpha-synuclein aggregation levels in living systems is critical. Western blotting represents one potential approach to this problem; however, this technique can often be limited by selectivity of available antibodies and experimental reproducibility. Herein, we describe a novel luminescence-based assay capable of detecting alpha-synuclein solubility in bacterial cells. This platform can report on the influence of disease-relevant mutations and small molecules. Antibodies are …

Use Of A Novel Whole-Body Imaging Approach To Predict Resting Metabolic Rates In Athletes, Nicole Vencil

College of Education and Human Sciences: Dissertations, Theses, and Student Research

Prediction of energy expenditure allows for calculation of appropriate energy requirements, which is especially important for athletes. Resting metabolic rate (RMR) is the greatest contributor to total daily energy expenditure (TDEE) and is typically measured via indirect calorimetry. Indirect calorimetry is not always available, which results in the need for predictive equations. Most predictive equations have been developed with participants resembling the general population and have not been found to be appropriate for athletes, as they may incorrectly predict RMR due to the unique differences of body composition between athletes and the general population. The purpose of the present study …

Connectivity Differences Between Gulf War Illness (Gwi) Phenotypes During A Test Of Attention, Tomas Clarke, Jessie Jamieson, Patrick Malone, Rakib U. Rayhan, Stuart Washington, John W. Vanmeter, James N. Baraniuk

Department of Mathematics: Faculty Publications

One quarter of veterans returning from the 1990–1991 Persian Gulf War have developed Gulf War Illness (GWI) with chronic pain, fatigue, cognitive and gastrointestinal dysfunction. Exertion leads to characteristic, delayed onset exacerbations that are not relieved by sleep. We have modeled exertional exhaustion by comparing magnetic resonance images from before and after submaximal exercise. One third of the 27 GWI participants had brain stem atrophy and developed postural tachycardia after exercise (START: Stress Test Activated Reversible Tachycardia). The remainder activated basal ganglia and anterior insulae during a cognitive task (STOPP: Stress Test Originated Phantom Perception). Here, the role of attention …

Oxygenation And Activation Of The Vastus Lateralis During Dynamic Constant External Resistance Leg Extension Muscle Actions In Older Women With And Without Sarcopenia, Brianna D. Mckay

College of Education and Human Sciences: Dissertations, Theses, and Student Research

The purpose of the present study was to compare muscle strength, size, activation, and oxygenation between older women with and without sarcopenia during dynamic fatiguing leg extension bouts with high (5-repetition maximum[5-RM]) and low (30% of estimated 1-RM[30%1-RM]) loads. Eleven women (n = 6 non-sarcopenic [mean ± SE; age = 75.8 ± 2.6y] and n = 5 sarcopenic [age = 74.5 ± 3.1y]) were screened for eligibility and sarcopenic status. Descriptive assessments including demographics (age, height, and weight), body composition by dual-energy x-ray absorptiometry (fat mass[FM], fat-free mass[FFM] and percent body fat[BF%]), muscle size by ultrasonography (leg extensor muscle cross-sectional …

The Role Of Inflammatory Pathways In Development, Growth, And Metabolism Of Skeletal Muscle In Iugr Offspring: Blood Gene Expression Of Inflammatory Factors As Novel Biomarkers For Assessing Stress And Wellbeing In Exotic Species, Robert J. Posont

Department of Animal Science: Dissertations, Theses, and Student Research

Our first study identified the effects of maternal inflammation-induced intrauterine growth restriction (MI-IUGR) on growth and muscle glucose metabolism in offspring supplemented with curcumin. MI-IUGR lambs exhibited asymmetric growth restriction at birth and 30d of age, but normal glucose-stimulated insulin secretion. Hindlimb glucose oxidation was reduced by MI-IUGR and not improved by curcumin supplementation. Ex vivo muscle glucose oxidation was reduced by MI-IUGR but improved somewhat by curcumin. These finding indicate that fetal programming responses to MI contribute to neonatal growth and metabolic deficits. Neonatal curcumin supplementation had minimal effect on growth deficits but may improve glucose metabolism. …

Body Condition Helps To Explain Metabolic Rate Variation In Wolf Spiders, Stella F. Uiterwaal, John P. Delong

School of Biological Sciences: Faculty Publications

1. Metabolism is the fundamental process that powers life. Understanding what drives metabolism is therefore critical to our understanding of the ecology and behavior of organisms in nature.

2. Metabolic rate generally scales with body size according to a power law. However, considerable unexplained variation in metabolic rate remains after accounting for body mass with scaling functions.

3. We measured resting metabolic rates (oxygen consumption) of 227 field-caught wolf spiders. Then, we tested for effects of body mass, species, and body condition on metabolic rate.

4. Metabolic rate scales with body mass to the 0.85 power in these wolf spiders, …

The Impact Of Whoop Technology On Sleep, Recovery, And Performance In Naia Baseball Players, Nolan Harms

Department of Teaching, Learning, and Teacher Education: Theses and Other Student Research

Many key factors – including but not limited to – sleep, nutrition, travel, stress, and practice influence the optimization of athletic performance. Although previous studies have investigated the use of wearable technology in sport to track several such factors, peer-reviewed research specific to WHOOP technology is limited at best. The purpose of this study was to examine the impact of WHOOP technology on sleep, recovery, and batting performance in healthy NAIA baseball players. Data was collected over the course of 4 weeks of in-season play on 10 varsity NAIA baseball players (20.40 ± 0.97 years). All games – 18 total …

Biology Of Exosomes And Their Microrna Cargos In Human And Bovine Milk, Amy Lynn Leiferman

College of Education and Human Sciences: Dissertations, Theses, and Student Research

Exosomes are small, cargo-containing vesicles secreted by cells to facilitate intercellular communication. Of exosome cargos, microRNAs are especially interesting because of their involvement in gene regulation. Recently, our lab has shown that exosomes and their microRNA cargo are absorbed through the diet and elicit effects exogenously. Human and animal milk contain exosomes, which may have implications in infant and adult nutrition. There is evidence that bovine milk exosomes enhance growth of murine C2C12 myotube cell cultures, but whether this translates to muscle in vivo is unknown. The USDA National Nutrient Database for Standard Reference is lacking up-to-date information about human …

The Relationship Between Habitual Physical Activity And Food Choices, Safiya E. Beckford

Department of Nutrition and Health Sciences: Dissertations, Theses, and Student Research

Physical activity (PA) and exercise aid in prevention and treatment of obesity and its comorbidities. Previous research has demonstrated a J-shaped curve between activity level and food intake, but minimal research examines whether PA and exercise affect food choices. As such, the aim of this study was to determine the relationship between habitual PA and exercise with food choices. 174 participants completed an electronic survey involving a series of binary choices among food options (aided by visual food cues) with varying reward values and time points. Participants also completed monetary binary choice questions and an exercise and activity questionnaire, with …

Production Of A Gonadotropin-Releasing Hormone 2 Receptor Knockdown (Gnrhr2 Kd) Swine Line., Amy T. Desaulniers, Rebecca Middleton, Ginger A. Mills, Clay A. Lents, Brett R. White

Department of Animal Science: Faculty Publications

Swine are the only livestock species that produce both the second mammalian isoform of gonadotropin-releasing hormone (GNRH2) and its receptor (GNRHR2). Previously, we reported that GNRH2 and GNRHR2 mediate LH-independent testosterone secretion from porcine testes. To further explore this ligand-receptor complex, a pig model with reduced GNRHR2 expression was developed. Small hairpin RNA sequences targeting porcine GNRHR2 were subcloned into a lentiviral-based vector, lentiviral particles were generated and microinjected into the perivitelline space of zygotes, and embryos were transferred into a recipient. One GNRHR2 knockdown (KD) female was born that subsequently produced 80 piglets from 6 litters with 46 hemizygous …

Patterns Of Morphological And Molecular Evolution In The Antillean Tree Bat, Ardops Nichollsi (Chiroptera: Phyllostomidae), Roxanne J. Larsen, Peter A. Larsen, Caleb D. Phillips, Hugh H. Genoways, Gary G. Kwiecinski, Scott C. Pedersen, Carleton J. Phillips, Robert J. Baker

University of Nebraska State Museum: Mammalogy Papers

Species endemic to oceanic islands offer unique insights into the mechanisms underlying evolution and have served as model systems for decades. Often these species show phenotypic variation that is correlated with the ecosystems in which they occur and such correlations may be a product of genetic drift, natural selection, and/or environmental factors. We explore the morphologic and genetic variation within Ardops nichollsi, a species of phyllostomid bat endemic to the Lesser Antillean islands. Ardops nichollsi is an ideal taxon to investigate the tempo of evolution in Chiroptera, as it: is a recently derived genus in the family Phyllostomidae; contains …

Stable Engraftment Of Bifidobacterium Longum Ah1206 In The Human Gut Depends On Individualized Features Of The Resident Microbiome, María X. Maldonado-Gómez, Inés Martínez, Francesca Bottacini, Amy O’Callaghan, Marco Ventura, Douwe Van Sinderen, Benjamin Hillmann, Pajau Vangay, Dan Knights, Robert W. Hutkins, Jens Walter

Department of Food Science and Technology: Faculty Publications

Live bacteria (such as probiotics) have long been used to modulate gut microbiota and human physiology, but their colonization is mostly transient. Conceptual understanding of the ecological principles as they apply to exogenously introduced microbes in gut ecosystems is lacking. We find that, when orally administered to humans, Bifidobacterium longum AH1206 stably persists in the gut of 30% of individuals for at least 6 months without causing gastrointestinal symptoms or impacting the composition of the resident gut microbiota. AH1206 engraftment was associated with low abundance of resident B. longum and underrepresentation of specific carbohydrate utilization genes in the pre-treatment microbiome. …

Effect Of Taste Stimuli On Swallowing Function In Persons With Traumatic Injuries, Megan Asselin, Angela M. Dietsch

UCARE: Research Products

Background

Swallowing disorders are prevalent and costly. As of now, there are limited therapeutic options available to treat them. Extant research in limited populations has suggested that swallowing mechanics can be improved by extremely sour liquids, but this has not been tested in traumatically injured populations. However, sour tastants are unpleasant, and more palatable taste mixtures have not been tested.

Methods

The quantitative data were extracted from an existing pool of de-identified video fluoroscopic swallowing studies (moving radiographs) obtained from traumatically injured young adults under another research protocol. Each participant completed swallows of custom-mixed plain, sour, and sweet-sour boluses. Positions …

Factors Affecting The Immune System Of The Ornate Box Turtle (Errapene Ornata), Michelle W. Mcquinn, Abigail A. Neyer, Gwendolyn C. Bachman

UCARE: Research Products

While many studies have detailed the complex intricacies of the endothermic immune system, relatively little is known about the immune system of ectotherms--specifically, reptiles. In an attempt to gain more knowledge about the factors affecting reptilian immune function, ornate box turtles (Terrapene ornata) were subjected to chronic stress in the form of high ambient temperatures in a semi-natural environment. It was hypothesized that chronic stress would lead to elevated levels of corticosterone in the blood, which would, in turn, suppress immune activity. It was found that body temperature and body mass in particular were significantly affected by chronic heat stress. …

Longevity Of Mineral Supplements Within The Soil And Associated Use By White-Tailed Deer, Brian C. Peterson, Keith D. Koupal, Andrew K. Schissel, Cody M. Siegel

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Humans have baited wildlife such as white-tailed deer (Odocoileus virginianus) for generations with the primary purpose of increasing hunting harvest success. Baiting regulation changes are often considered by state management agencies as they pertain to hunting opportunity, fair chase, and disease risk. Cervids require a variety of minerals to supplement biological processes, especially sodium (Na), calcium (Ca), and phosphorus (P). We developed artificial mineral supplement sites set in front of trail cameras to monitor deer use. Pooled soil samples were collected at mineral sites and compared to the surrounding area to determine the longevity of elevated minerals levels …

A New Method For Shear Wave Speed Estimation In Shear Wave Elastography, Aaron J. Engel, Gregory R. Bashford

Biomedical Imaging and Biosignal Analysis Laboratory

Visualization of mechanical properties of tissue can aid in noninvasive pathology diagnosis. Shear wave elastography (SWE) measures the elastic properties of soft tissues by estimation of local shear wave propagation speed. In this paper, a new robust method for estimation of shear wave speed is introduced which has the potential for simplifying continuous filtering and real-time elasticity processing. Shear waves were generated by external mechanical excitation and imaged at a high frame rate. Three homogeneous phantoms of varying elastic moduli and one inclusion phantom were imaged. Waves propagating in separate directions were filtered and shear wave speed was estimated by …

Lh-Independent Testosterone Secretion Is Mediated By The Interaction Between Gnrh2 And Its Receptor Within Porcine Testes, Amy T. Desaulniers, Rebecca A. Cederberg, Ginger A. Mills, J. Joe Ford, Clay A. Lents, Brett R. White

Department of Animal Science: Faculty Publications

Unlike classic gonadotropin-releasing hormone 1 (GNRH1), the second mammalian isoform (GNRH2) is an ineffective stimulant of gonadotropin release. Species that produce GNRH2 may not maintain a functional GNRH2 receptor (GNRHR2) due to coding errors. A full-length GNRHR2 gene has been identified in swine, but its role in reproduction requires further elucidation. Our objective was to examine the role of GNRH2 and GNRHR2 in testicular function of boars. We discovered that GNRH2 levels were higher in the testis than in the anterior pituitary gland or hypothalamus, corresponding to greater GNRHR2 abundance in the testis versus the anterior pituitary gland. Moreover, GNRH2 …

The Role Of Rfamide-Related Peptide 3 (Rfrp3) In Regulation Of The Neuroendocrine Reproductive And Growth Axes Of The Boar, Jennifer F. Thorson, Amy T. Desaulniers, Chanho Lee, Brett R. White, J. Joe Ford, Clay A. Lents

Department of Animal Science: Faculty Publications

RFamide-related peptide 3 (RFRP3) has been implicated in regulating reproduction and growth. This regulation appears to be dependent upon sex, species, physiological status, and developmental stage. The objective of the present study was to evaluate the effects of RFRP3 on circulating concentrations of luteinizing hormone (LH) and growth hormone (GH) in mature boars. The hypothesis was RFRP3 would reduce circulating concentrations of LH and increase concentrations of GH. Meishan boars (716.6±2.8 days of age; 125.0±12.4kg BW) were randomly assigned to treatment: saline (n=4) or RFRP3 (8.5mg; n=5). Plasma was collected at 15-min intervals during 3 periods: pre-treatment, treatment, and post-treatment. …