Life Sciences Commons^™

Physiological Impacts And Lactational Performance Of Dairy Cows Fed Brown Midrib Corn Silage During Dry Period Through Early To Midlactation, Alexandra Windley Kelley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Developing solutions to the metabolic stress experienced by cows during the transition period is very important because it can negatively influence lactational performance. The objectives were to: 1) compare physiological changes through body weight (BW) and concentrations of non-esterified fatty acids (NEFA) and β-hydroxybutyric acid (BHBA) and 2) evaluate feed intake, milk production, and energy balance (EB) of cows fed brown midrib corn silage (BMRCS)-based diets when compared with conventional corn silage (CCS)-based diets during the transition. At 4 wk prior to parturition, 40 dry multiparous Holstein cows …

Ghrelin Concentrations In Milk And Plasma Of Dairy Cows During Early Lactation, Sameer M. Alhojaily

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Ghrelin is a hormone produced mainly by the cells lining the gastric mucosa. Ghrelin was first extracted from human and rat stomachs, and identified as an endogenous stimulator of growth hormone release. Ghrelin is synthesized and produced in several tissues, but the gastric mucosa remains the major source of circulating ghrelin. Besides growth hormone release, ghrelin stimulates appetite and plays some major roles in different organs. In several studies, ghrelin was described as a hormone with multiple functions and diverse biological actions. Ghrelin exists in two major forms, active ghrelin and inactive ghrelin, and only the active from binds to …

Producing An Ovine Model Of Cystic Fibrosis, Kira Perry Morgado

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Cystic Fibrosis (CF) is an autosomal recessive disease that significantly affects quality of life and lifespan. There are currently no effective animal models of CF that mimic the human disease state. This prevents the development of pharmaceutical treatments for patients. Sheep have been considered for a useful animal model because of their size, life expectancy, and similarities in their anatomy and physiology. In order to generate a sheep transgenic model to study CF we have produced two Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene targeting DNA vectors containing large regions of homology to the CFTR gene in sheep. One of …

Nutrient Utilization, Lactational Performance, And Profitability Of Dairy Cows By Feeding Protein Supplements In High-Forage Lactation Diets, Kathryn Neal

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Due to the increasing cost of soybean meal and concerns of excess N being excreted into the environment, new protein supplements have been developed. Two products that have shown potential in increasing N utilization efficiency are slow release urea (SRU; Optigen) and ruminal escape protein derived from yeast (YMP; DEMP). The objective of this study was to assess the effects of feeding these 2 supplements in high-forage [(54% of total dietary dry matter (DM)] dairy diets on nutrient utilization, feed efficiency, lactational performance of dairy cows, and their impacts on income-over feed costs. Twelve …

Assessing The Impact Of Supplements, Food Aversions, And Silica On Medusahead Use By Sheep, Tyler Hamilton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Ranchers, farmers, land managers, and resource management agencies have been plagued with various types of invasive weeds for decades, ultimately affecting millions of acres of viable wildlife habitat, grazing, and recreational opportunities. Invasive weeds often have nutritional contexts that negatively affect animals in some way, increasing the incentive to avoid consuming it by various animal species and domestic livestock. With the current amount of land infested with this weed, and the limited knowledge of the reason for avoidance, the underlying causes of livestock avoidance require in-depth and fundamental understanding.

In my MS program, I sought to explore the relationship of …

Ambient Temperature, Calf Intakes, And Weight Gains On Preweaned Dairy Calves, Sheldon D. Holt

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

There has been little research conducted on the physiological response of calves to temperatures outside thermal neutrality and its effects on intake and weight gain. The effects of ambient temperature on Holstein dairy calves intakes and weight gain were evaluated over a 12-month period at the Utah State University Caine Dairy.

Ambient temperature was monitored using a weather station located 1.3 kilometers from the dairy. Calf health was monitored daily using the University of Wisconsin-Madison School of Veterinary Medicine scoring criteria. Calves were fed whole milk and free choice calf starter. Weight gain, wither and hip height, starter intake, and …

American Bison Ecology And Bison-Cattle Interactions In An Isolated Montane Environment, Dustin H. Ranglack

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

As bison are considered to be ecologically extinct, and negative interactions between bison and cattle are perceived to limit bison restoration and cattle production, I designed a series of studies to test for potential competition between bison (Bison bison) and cattle (Bos taurus) for forage on the Henry Mountains in southern Utah. These studies provide insight into key information gaps previously identified by the Utah Division of Wildlife Resources (UDWR), Bureau of Land Management, and the local grazing association. The results indicate that bison and cattle are not strong competitors for forage on the Henry Mountains. …

Effects Of Condensed Tannins On The Toxicity Of Fireweed (Senecio Madagascariensis) To Cattle, Carolyn L. Wong

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Fireweed (Senecio madagascariensis) is a noxious and invasive weed affecting pastures in Hawaii, Australia, and South America. Fireweed contains compounds called pyrrolizidine alkaloids that are toxic to most grazing mammals. Toxic effects to cattle include irreversible damage to liver cells, hardening of the liver, and loss of liver function, which may lead to jaundice, swelling, and the accumulation of fluids in the stomach and other physiological malfunctions. External effects include rough appearance, diarrhea, low energy and dullness, photosensitization, and abnormal behavior, many of which can lead to death. Fireweed also can reduce pasture productivity by as much as …