Animal Sciences Commons^™

Obesity, Metabolic Hormone Signaling, And Granulosa Cell Gene Expression, Elizabeth Mack

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

It has become increasingly clear that female obesity is associated with a myriad of adverse side effects including abnormal female reproduction due, in part, to amenorrhea and anovulatory infertility. The lethal yellow (LY) mouse possesses a deletion mutation which results in ectopic expression of agouti and adult-onset obesity. Furthermore, LY mice exhibit premature loss of fertility, which has been associated with progressive obesity making the LY mouse line an excellent model to study the effects of obesity-dependent factors on ovarian function. In the current study blood serum and granulosa cells were obtained from LY (Ay/a) and age-matched B6 controls (C57BL/6J) …

Ethanol Byproduct Feeds: Determining Accurate Fiber Content, Nutrient Composition And Variability, Storing With Low-Quality Forages, And Fiber Utilization In Finishing Diets, Crystal D. Buckner

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

The growing ethanol industry has produced vast quantities of distillers grains plus solubles (DGS) in the wet (WDGS) and dry forms and Sweet Bran wet corn gluten feed (SB). Previous research has demonstrated that these byproduct feeds result in improved feeding values compared to grass in growing diets and corn in finishing diets, with positive economic returns. Four experiments were conducted to evaluate dry matter determination methods and variability of nutrient composition for WDGS, determining the accurate method for measuring NDF in corn and DGS, compare feeding WDGS mixed with straw as either fresh or ensiled, and evaluate fiber digestibility …

Distillers' Grains With Solubles For Feedlot Cattle: Finishing Performance, Lipid Metabolism, And Ethanol Greenhouse Gas Balance, Virgil R. Bremer

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

Previous University of Nebraska feedlot research trials have characterized the feed value of wet distillers grains plus solubles (WDGS). These trials were summarized with meta-analysis methodology and indicated the feed value of WDGS interacts with corn processing type, cattle age (calf-fed or yearling), and inclusion level. Two steer finishing studies and a metabolism study were conducted to understand the impact of different lipid sources in WDGS on WDGS feed value. A biphasic lipid extraction procedure was developed to analyze feed samples from these trials that was more effective than Goldfisch ether extraction at lipid analysis of byproduct feds. These trials …

Characterization Of Neuronal Groups Regulating Sexual And Agonistic Behavior In Male Chicken (Gallus Gallus), Jingjing Xie

Graduate Theses and Dissertations

The study aimed to understand the neuronal regulation of male sexual and agonistic behavior in broiler breeders. First, brain structures associated with sexual and agonistic behavior were identified by mapping Fos expression. The ventromedial subnucleus of medial portion of bed nucleus of the stria teriminalis (BSTM2) was specifically activated by male courtship behavior. The medial preoptic nucleus (POM) and lateral septum (SL) were associated with both sexual and agonistic behaviors. The bed nucleus of the pallial commissure (NCPa) and the paraventricular nucleus (PVN) were closely related to stress. Second, Fos-ir neurons were phenotyped by double labeling Fos with aromatase (ARO) …

Marketing And Feeding Cull Cows, Dillon M. Feuz

All Current Publications

This publication provides ways to enhance the value of cull cows by innovating marketing and feeding practices.

Influence Of Physiochemical And Watershed Characteristics On Mercury Concentration In Walleye, Sander Vitreus, M., Cari-Ann Hayer, Steven R. Chipps, J. J. Stone

Natural Resource Management Faculty Publications

Elevated mercury concentration has been documented in a variety of fish and is a growing concern for human consumption. Here, we explore the influence of physiochemical and watershed attributes on mercury concentration in walleye (Sander vitreus, M.) from natural, glacial lakes in South Dakota. Regression analysis showed that water quality attributes were poor predictors of walleye mercury concentration (R² = 0.57, p = 0.13). In contrast, models based on watershed features (e.g., lake level changes, watershed slope, agricultural land, wetlands) and local habitat features (i.e., substrate composition, maximum lake depth) explained 81% (p = 0.001) …

Corn Hybrids: Deer Taste The Difference, Joshua A. Delger, Kevin L. Monteith, Jonathan A. Jenks

Natural Resource Management Faculty Publications

As daylight begins to illuminate the countryside, a cold wind rustles through the leaves of the weedy rows of corn that you barely had time to get in the ground this past spring. The corn plants are stunted, the few small ears of corn that did grow are not even enticing to passing blackbirds, and that stud buck captured on your trail-camera months earlier is nowhere to be seen. Meanwhile, a couple hundred yards across the fence to the south, you hear the unmistakable sound of deer running through corn. Your heart rate involuntarily increases. As the sun continues to …

Rangeland Condition Assessment Of A Portion Of The Cal Poly Sheep Unit, Colin S. Mckim

Animal Science

This rangeland condition assessment was conducted as part of the Cal Poly Rangeland Condition Assessment Project. Five pastures comprising 31.7 acres at the Cal Poly sheep unit were assessed to collect baseline ecological information. Methods used were Line-point Intercept, Belt Transect, Residual Dry Matter, and the rangeland health indicators recommended by Pyke et al., 2002. Additionally, a preliminary species list was collected. The rangeland health assessment method found all pastures to have no to slight departure from the local reference area when evaluated for soil and site stability, hydrologic function, and biotic integrity.

Life History And Habitat Use Of The Juvenile Alabama Shad (Alosa Alabamae) In Northern Gulf Of Mexico Rivers, Paul Fraser Mickle

Dissertations

The Alabama shad, Alosa alabamae, is an anadromous species that is in decline and has seen extirpations from impoundments as well as decreased water quality. Alabama shad live in the Gulf of Mexico and ascend Northern Gulf of Mexico Drainages to reproduce early in the year (January-May). The juveniles spend the majority of the year in these freshwater systems before emigrating out to the Gulf of Mexico as late as December.

This dissertation focuses on the juvenile life stages that occur within the Northern Gulf of Mexico drainages. Spawning conditions of the river, as well as the habitat and diet, …

Identification And Characterization Of Micrornas In Porcine Gametes And Pre-Implantation Embryos, Erin Curry

All Dissertations

MicroRNAs (miRNAs) are short ribonucleic acids that ultimately affect the production of proteins. Although miRNAs are involved in nearly every biological process examined to date, little is known of the identity or function of miRNA in porcine reproductive tissues or their potential involvement in reproductive processes in pigs or other species. The objective of this dissertation research was to determine the presence of miRNAs in porcine gametes and both in vivo- and in vitro- produced pre-implantation embryos and to identify differences in miRNA expression between normal and aberrant samples. Using a heterologous RT-PCR approach, we demonstrated the presence of a …

A New Partial Skeleton Of A Cryptocleidoid Plesiosaur From The Upper Jurassic Sundance Formation Of Wyoming, Benjamin C. Wilhelm, F. Robin O’Keefe

Biological Sciences Faculty Research

Cryptocleidoid plesiosaurs from the Upper Jurassic are well known from the Oxford Clay (Callovian) of the United Kingdom. The plesiosaurs of the nearly coeval Sundance Formation (Oxfordian) of North America are poorly known, but are thought to include two cryptocleidoid taxa:Pantosaurus striatus and Tatenectes laramiensis. Here we present two specimens recently recovered from the Bighorn Basin of Wyoming. The first specimen comprises three articulated adult cervical vertebrae and fragments of a fourth. This specimen preserves a posteriorly directed cervical neural spine, a character diagnostic of Pantosaurus striatus. It also resembles Pantosaurus in the morphology of its cervical …

Fertilization And Supplementation Strategies For Steers Grazing Smooth Bromegrass Pastures, Andrea K. Watson

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

Since 2004, fertilizer prices have doubled due to increases in energy prices for production and increased demand for N fertilizer due to high grain prices. This leads to questioning the cost effectiveness of increasing forage production with N fertilizer. At the same time, an increase in ethanol production creates an increase in the production of by-products of the ethanol industry, such as distillers grains. Distillers grains have been shown to be an excellent feed for ruminants both as a supplement while grazing and as part of a complete diet in the feedlot. Distillers grains provide protein, fat, and highly digestible …

Strategies For Beef Cattle Adaptation To Finishing Diets, Ractopamine Hydrochloride Utilization, And Mature Size Genetic Selection, Marco G. Dib

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

A cattle finishing experiment was conducted to evaluate effects of intermittent feeding of Optaflexx compared to none or continuous feeding. Four treatments were evaluated, the negative control consisted of 63 days on the same diet without Optaflexx, wherea the positive control consisted of Optaflexx supplemented daily during the last 35 days before harvest. The 4-day intermittent treatment consisted of feeding Optaflexx for7 days, followed by 4 days of no Optaflexx, and the 7-day intermittent treatment 7 d on Optaflexx, followed by 7 days off. Regardless of the delivery pattern, feeding Optaflexx increased ADG, DMI, and live BW compared to negative …

Arkansas Animal Science Department Report 2010, David L. Kreider

Arkansas Agricultural Experiment Station Research Series

No abstract provided.

Design Standards Within Constructed Wetlands For The Reduction Of Mosquito Populations In Clark County, Nevada, Phillip C. Bondurant

UNLV Theses, Dissertations, Professional Papers, and Capstones

Wetlands are considered one of the most productive ecosystems in the world and provide many benefits to the environment. However, the slow moving and sometimes stagnant water created by the vegetation in the wetland creates an ideal environment for the proliferation of mosquitoes. Mosquitoes are the most important insect disease vector worldwide. The presence of mosquitoes within wetlands increases the risk of disease transmission among workers and visitors creating a public health concern. Effective design standards aimed at reducing mosquito breeding habitat should be implemented during the construction and planning phase of wetland development to effectively reduce the mosquito populations. …

Reconstructing Species Responses To Past Climatic Changes Using Niche Modeling And Genetic Data, Tereza Jezkova

UNLV Theses, Dissertations, Professional Papers, and Capstones

Glacial – interglacial cycles have a pronounced impact on species distributions and genetic structure. Many species shift their distributions to lower latitudes and altitudes during the colder glacial periods and expand northwards and up the elevation during warmer interglacial periods. Some species however are capable of adapting to changing environment which allows them to persist in place despite climatic changes. I explored how climatic changes after the last glacial maximum (LGM) effected two species inhabiting the deserts of western North America: one mammal (Chisel-toothed Kangaroo Rat, Dipodomys microps) and one reptile (Desert Horned Lizard, Phrynosoma platyrhinos). I used …

Assessment Of Ruminal Fermentation Characteristics Of Condensed Tannin-Containing Forages Using Continuous Cultures, Christina Marie Williams

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Two independent studies were conducted to assess the effects of feeding condensed tannin (CT)-containing forages to continuous cultures to evaluate their impacts on ruminal fermentation and digestibility, with an emphasis on methane (CH4) and ammonia-N (NH3-N) production. In Chapter 3, treatments consisted of: 1) 100% alfalfa hay (AH), 2) 50% AH and 50% birdsfoot trefoil hay (dry matter (DM) basis; AHBFTH), and 3) 100% birdsfoot trefoil hay (BFTH). Three replicated runs lasted 8 d each, with the first 5 d allowed for microbial adaptation to the diets, and 3 d for data collection and sampling. Methane, neutral detergent fiber (NDF) …

Assessing Linkages Among Landscape Characteristics, Stream Habitat, And Macroinvertebrate Communities In The Idaho Batholith Ecoregion, Andrew C. Hill

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Understanding the composition of lotic communities and the landscape processes and habitat characteristics that shape them is one of the main challenges confronting stream ecologists. In order to better understand the linkages among landscape processes, stream habitat, and biological communities and to understand how accurately our measurements represent important factors influencing biological communities, it is important to test explicit hypotheses regarding these linkages. Increasing our understanding of aquatic communities in a hierarchical context and recognizing how well our measurements represent factors structuring aquatic communities will help managers better evaluate the influence of land management practices on aquatic ecosystems, direct conservation …

Physiological Implications Of Natural Versus Induced Arousal From Torpor, Jenifer C. Utz

UNLV Theses, Dissertations, Professional Papers, and Capstones

During the hibernation season, animals oscillate between periods of torpor and periods of interbout arousal (IBA). During torpor, body temperature is often near 0° C and metabolism is severely depressed. Oxygen consumption, a proxy for aerobic metabolism, may fall to 1% of active values. Many physiological processes including cardiovascular, respiratory, and cellular functions nearly cease. During the IBA, euthermic body temperature is restored and most systemic and cellular processes function at fully active levels. The transition period between these two physiologically dissimilar states is called arousal.

The rate of rewarming (RRW) during arousal was previously expected to progressively increase until …

Distributions Of Sharks Across A Continental Shelf In The Northern Gulf Of Mexico, J. Marcus Drymon, Sean P. Powers, John Dindo, Brian Dzwonkowski, Terry A. Henwood

University Faculty and Staff Publications

Declines in shark populations have sparked researchers and fishery managers to investigate more prudent approaches to the conservation of these fish. As managers strive to improve data collection for stock assessment, fisheries-independent surveys have expanded to include data-deficient areas such as coastal regions. To that end, a catch series from a nearshore survey off Alabama was combined with data from a concurrent offshore survey with identical methodology to examine the depth use of sharks across the continental shelf (2–366 m). The combined data set contained 22 species of sharks collected from 1995 to 2008: 21 species in the offshore data …