Medicine and Health Sciences Commons^™

Rumen-Protected Methionine Supplementation Improves Lactation, Oxidative Status, And Immune Response During A Subclinical Mastitis Challenge In Lactating Dairy Cows., Anita Paz Lopez

Electronic Theses and Dissertations

Mastitis is a significant problem in the dairy industry, posing numerous challenges for dairy farmers worldwide. Mastitis refers to the inflammation of the mammary gland, primarily caused by bacterial infections. This condition affects the health and well-being of dairy cows and has severe economic implications for farmers and overall dairy production. The prevalence of mastitis substantially threatens milk quality, productivity, and profitability, making it a top concern in the dairy industry. Preventing mastitis in cows is crucial for maintaining the herd's health and ensuring highquality milk production. Nutritional strategies have recently gained greater attention due to a direct impact on …

Physiological State Determinants Of Maternal Cortisol Signaling And Its Impact On Offspring Quality And Fitness, Sydney Currier

Electronic Theses and Dissertations

Assessing the intergenerational effects of maternal stress is important for predicting how offspring will respond to changing environments. The overall aim of my thesis was to quantify the effects of maternal state on maternally derived egg cortisol and determine whether this variation in egg cortisol impacts Chinook salmon offspring performance and fitness in a sex-specific way. I quantified within-female changes in maternal energetics and reproductive metrics that I linked to egg quality and ultimately embryo survival. I found egg cortisol increases with increasing maternal plasma cortisol, and increases further as plasma cortisol levels rise with each day that eggs are …

Assessing Dairy Farm Employees Health, Leyby Stephany Guifarro Rodriguez

Electronic Theses and Dissertations

This Master thesis evaluates the impact of general health care and eating habits (Study 1), vision care (Study 2), and mental health status (Study 3) on Latino dairy farmworkers lifestyle and work performance in South Dakota. We hypothesized that the health status of dairy workers has a negative impact on the workers’ job performance. In study 1, data from a total of 70 participants were collected, using a face-to-face survey in Spanish, which allowed us to assess various topics and details related to employees’ daily routine tasks, eating habits, and general health status. Furthermore, recommendations to improve general health care …

Cortisol In Hair As A Measure Of Chronic Stress During Sow Gestation And The Pattern Of Cortisol In Blood During Parturition In Sows, Talia Everding

Electronic Theses and Dissertations

Cortisol is known as the stress hormone, as it influences many metabolic processes to maintain glucose homeostasis during stressful experiences, including physical and psychological stress. It can be detected in biological matrices such as blood and hair and is released rapidly during sudden stressors and continuously during longterm stress. Blood cortisol fluctuates rapidly in response to acute stressors like pain, exertion, and fear; in hair cortisol accumulates steadily over the period of hair growth and may be useful for detecting chronically elevated cortisol resulting from long-term stress. The objective of this research was to, 1) determine the influence of a …

Tobacco Enhances Bacterial-Induced Periodontal Bone Loss In Mice., Mina Iskander

Electronic Theses and Dissertations

Background: Tobacco smoking is the leading environmental risk factor for periodontal diseases. Delineation of the mechanisms underlying tobacco-induced or exacerbated periodontitis is hampered by the lack of an appropriate and reliable animal model. Hypothesis: We hypothesized that Porphyromonas-gingivalis-infected, cigarette smoke-exposed mice would represent reproducible models of acute (ligature model) and chronic (oral gavage model) tobacco-enhanced periodontitis that reflect multiple aspects of the disease noted in human smokers. Methods: In a chronic oral gavage disease model, Balb/c mice (6-8 weeks, 4 groups of n = 6 per group) were exposed to smoke produced by a Teague-10 smoking machine from 1R6F research …

The Potential For Dickeya Dianthicola To Be Vectored By Two Common Insect Pests Of Potatoes, Jonas K. Insinga

Electronic Theses and Dissertations

Dickeya dianthicola (Samson) causing blackleg and soft rot was first detected in potatoes grown in Maine in 2014. Previous work has suggested that insects, particularly aphids, may be able to vector bacteria in this genus between plants, but no conclusive work has been done to confirm this theory. In order to determine whether insect-mediated transmission is likely to occur in potato fields, two model potato pests common in Maine were used: the Colorado potato beetle (Leptinotarsa decimlineata Say) and the green peach aphids (Myzus persicae Sulzer). Olfactometry and recruitment experiments evaluated if either insect discriminates between infected and …

Alternative Treatment Options For Controlling Anthelmintic-Resistant Haemonchus Contortus Populations In South Dakota Sheep Herds, Adam Sarah

Electronic Theses and Dissertations

Haemonchus contortus is a common economically important gastrointestinal nematode that obliges the survival and productivity of small ruminants, especially sheep and goats. Anthelmintic resistance is a primary challenge in ruminant health management programs in preventing and controlling the H. contortus populations; therefore, there is a great necessity in finding and developing natural plant products for use as alternatives to commercial anthelmintics for controlling H. contortus in pastured sheep and goats. This dissertation has three major aims conducted in three separate studies: the first in vivo one was to evaluate the extended effect of a springtime, combined-treatment with 3 anthelmintics having …

Performance Differences Between Two Groups Of Commercial Pigs Following Experimental Infection With Prrs Virus 1-7-4, Erin Little

Electronic Theses and Dissertations

Porcine reproductive and respiratory syndrome virus (PRRSV) is the costliest swine disease in North America. Vaccines and management alone have not been effective in controlling this disease. Genetic selection for resilience may be a complimentary approach for controlling PRRSV. The objective of this study was to estimate performance differences between two groups of pigs from the same commercial line following infection with PRRSV 1-7-4: 1) pigs sired by boars selected based on a standard index (TN-S), which emphasized feed efficiency and carcass quality; and 2) pigs sired by boars selected based on an experimental index (TN-E), which emphasized feed intake, …

The Study Of Alcoholic Liver Diseases, Seun Emmanuel Owoseni

Electronic Theses and Dissertations

Excessive alcohol consumption is the primary contributing factor in the development of alcoholic liver diseases (ALD). Nicotine contained in tobacco is a major addictive alkaloid, which enhances the effects of ALDs. The major enzyme involved in nicotine metabolism is cytochrome P450 2A5 (CYP2A5) which is produced in the liver. Alcohol can stimulate the CYP2A5 enzyme. We utilized cyp2a5-/- knockout mice in this research to examine the effects of CYP2A5.

The cyp2a5-/- mice and wild-type (WT) mice were fed liquid ethanol diet with or without nicotine to induce ALD. Nicotine enhancing effects on ALD were observed in WT mice but not …

Improving Techniques To Study Equine Cervical Mucociliary Clearance, Melissa A. Hawkes

Electronic Theses and Dissertations

Bacterial uterine infections inflict major losses on the equine breeding industry. These infections usually arise from bacteria introduced at breeding. Micro-currents propelled by ciliated cells between the folds of the uterus and cervix have been proposed as a means by which contaminants are expelled. Previous data have shown possible ciliary micro-currents propelling carbon particles, occasionally rotating, through cervical folds. However, adherence to the epithelium may have interfered with movement of carbon in these studies. Therefore, we tested potentially non-adherent substances to reveal ciliary micro-currents on the equine cervix under high magnification video-endoscopy. We hypothesized that polyethylene green microspheres 1 - …

Evaluation Of Berberine As An Alternative To Antibiotics In Nursery Pig Diets, Emily Scholtz

Electronic Theses and Dissertations

Pig weaning process results in reduced growth performance and gut health of weaned pigs. Antibiotics can be added in diets for weaned pigs to improve growth performance and gut health, but their use is being discouraged because they can lead to development of antimicrobial resistant microorganisms. Thus, there is need for alternatives to antibiotics in diets for weaned pigs. The overall goal of this thesis research was to determine the effects of plant extracts (berberine, quercetin, and allyl isothiocyante [AITC]) as alternatives to antibiotics in weaned pig diets. The first objective of the research was to determine in vitro antimicrobial …

Effects Of Enzymatically Hydrolyzed Yeast Supplementation And Supplementation Frequency On Immune Parameters, Performance, And Digestibility Among Periparturient Beef Cows And Calves, Janine Swartz

Electronic Theses and Dissertations

Effects of enzymatically hydrolyzed yeast (EHY) and supplementation frequency (FREQ) on immune parameters among beef cows and calves was evaluated. Eighty multiparous (parity = 4.2 ± 0.3) cows were fed a common brome hay-based diet (CP = 8.0 ± 0.17%). Cows were blocked by expected calving date and stratified by body condition score (BCS) before random assignment of treatment. Beginning 88 ± 5 d prior to parturition, cows were provided 1 kg daily or 3 kg every 3 d of a soybean hull-based supplement (CP = 34.0, % of DM) that contained 0 or 3 g/kg EHY. The daily supplement …

Therapy Dogs And The Impact On Employees In The Pediatric Medical Setting, Laine Foith

Electronic Theses and Dissertations

More than 40% of nurses reported experiencing significant burnout. Burnout is characterized by disengagement, cynicism, negative views of personal accomplishment and ability, and emotional exhaustion. The healthcare providers that experience burnout can possibly expect a decrease in ability to recognize/report errors, increase of negative feelings toward the patient, and decrease levels of patient satisfaction (Ernest, 2014). One of the ways Schub (2015) suggested to regulate burnout for employees was to provide psychosocial support to colleagues to reduce stress. This study is one of the first attempts to bridge the gap between the unknown correlation between qualitative and quantitative benefits of …

Effects Of Melatonin On Heartbeat And Possible Identification Of A Melatonin Receptor In Drosophila Melanogaster, Tricia L. Vankirk

Electronic Theses and Dissertations

Chapter 1 of this manuscript is a literature review that serves as an introduction to the entire dissertation. Chapter 2 examines the effects of the melatonin injection on heart rate and rhythmicity in Drosophila melanogaster Canton-S (wild-type) pupae and pupae bearing a variety of heart mutations. Chapter 3 investigates further the possible mechanisms of melatonin’s ability to increase heart rhythmicity without significantly affecting heart rate. A melatonin antagonist, luzindole; a high-affinity melatonin agonist, 2-iodomelatonin and RNAi techniques are used to identify a possible melatonin receptor in Drosophila melanogaster.

An appendix contains a previously published manuscript detailing experiments performed at the …

Virus-Like Particles Generaged By Expressing Proteins Of Porcine Reproductive And Respiratory Syndrome Virus (Prrsv) Using The Recombinant Baculovirus Expression System, April Anne Nelsen

Electronic Theses and Dissertations

Porcine reproductive and respiratory syndrome virus (PRRSV) is an enveloped, single stranded, positive sense RNA virus and a member of Arteriviridae. Its genome encodes 10 open reading frames for at least 7 structural proteins and 14 non-structural proteins. Membrane (M), Nuclepcapsid (N), and Glycoprotein-5 (GP5) are the major structural proteins of PRRSV, while Envelope (E), Glycoprotein-2 (GP2), Glycoprotein-3 (GP3), and Glycoprotein-4 (GP4) are the minor structural proteins of PRRSV. GP5 induces neutralizing antibodies and forms heterodimers with M, while N is the most immunogenic protein of PRRSV. Previous studies have shown viral structural proteins are able to form virus-like particles …

Effects Of Step Training On The Kidneys Following Spinal Cord Injury In Rats., Pradeepa Poudyal

Electronic Theses and Dissertations

Detrusor-sphincter dyssynergia after chronic spinal cord injury (SCI) leads to over-distention, high bladder pressures and vesico-ureteric reflux into the kidney, resulting in repeated infections and pyelonephritis. Given the importance/limited knowledge of SCI effects on the upper urinary tract, this study assessed expression of two proteins in the kidneys of contused (T9) male rats relative to controls that are indicative of tissue stress/damage (TGFβ, CD11b). The impact of two therapeutic rehabilitation strategies, 60 minutes of step training and general exercise, was then assessed on these protein levels relative to non-trained SCI controls, plus the effectiveness of a shorter training duration (30 …

Effect On Heartbeat Of Drosophila Melanogaster Of Mutations In The Calcium Channel Encoding Cacophony Gene And Its Interaction With The Rna Helicase Mutant Maleless^Napts, Vanessa Mcgowan

Electronic Theses and Dissertations

There is a lack of information concerning the genetics of heart disease, especially of those due to aberrant pacemaker activity. Drosophila melanogaster is an ideal candidate for research in this area because of its suitability to genetic manipulation and its accessible genetic database. What is most compelling, however, is that the genesis of heartbeat is Drosophila is strikingly similar to that in many other organisms, including mammals. The myogenic heart of DrosophiIa melanogaster is stimulated to contract by a caudal pacemaker, which is regulated by ion channel interactions. A voltage-gated calcium channel of PIQ- or N-type is implicated in the …

Evolution Of Lake Malawi Cichlid Fishes (Perciformes: Teleostei), Peter F. Smith

Electronic Theses and Dissertations

The cichlid fish species flocks of East Africa provide a compelling model system in which to study the process of speciation. In Lake Malawi, greater than 1000 species of cichlids have emerged since the filling of the lake basin about 1 million years ago. Over 99% of the Lake Malawi haplochromine cichlids are endemic, suggesting that most of this diversification has taken place within the temporal and spatial boundaries set by the Lake's shores. Moreover, many of these species are endemic to small areas within the lake, indicating that speciation has occurred very recently or perhaps is in progress in …

Adaptation Of Striped Bass To Sea Water Following Direct Transfer From Freshwater: Morphological, Biochemical, And Physiological Parameters, Judy A. King

Electronic Theses and Dissertations

There has been heightened interest in the biology of striped bass (Morone saxatilis) because of increased pollution in their native spawning grounds and because of their extensive use in landlocked sport fisheries. Their euryhalinity makes them an excellent species for osmoregulation studies. The objective of this research was to study the rate of adaptation of striped bass gills to sea water (3% salt) after direct transfer from freshwater using biochemical (ion transport enzyme levels), physiological (chloride efflux), and ultrastructural methods. Striped bass have specialized osmoregulatory cells located on the interlamellar and afferent surfaces of their gill filaments as shown by …

A Survey Of The Helminth Parasites Of Pheasants From Brown County, South Dakota, Donald E. Gilbertson

Electronic Theses and Dissertations

This paper presents a study of the helminth endoparasite of the Chinese or ring-necked pheasant (Phasianus colchicus). The digestive and respiratory tracts of 262 pheasants, all of which were collected in Brown County, South Dakota, were examined. Collections were ,made from January, 1961, through November of the same year. The problem was divided as follows: (1) locating and Identifying the helminth parasites, (2) relating parasitism to the age of the birds, (3) ascertaining the seasonal distribution of the parasites, and (4) determining what gross pathological changes were due to parasitism. Previous to this study, little or no literature was available …

A General Discussion Of Trichinella Spiralis (Owen), An Investigation Of Infection Of The Brown Rat, And A Life History Study Of The Parasite In The White Rat, Carl A. Johnson

Electronic Theses and Dissertations

The purpose of this treatise is threefold: first, to present a general discussion of Trichinella spiralis,; second, to present the results of an investigation of infection with trichinae of 100 brown rats; and third, to present the results of infecting white rats under laboratory conditions.