Life Sciences Commons^™

Evaluation Of Increasing Levels Of Mycotoxin-Containing Corn Fines On Diet Choice And Growth Performance Of Nursery Pigs, Duncan B. Paczosa

Theses and Dissertations--Animal and Food Sciences

Pigs fed mycotoxin contaminated diets at high concentrations will result in a detriment to health and performance. An initial study and a follow-up study were conducted to evaluate the effects of feeding increasing levels of mycotoxin-containing corn fines on growth performance, diet preference of pigs, and two possible mitigants.

The initial study was a 3 x 2 factorial containing three levels of fines (0, 10, and 20%, Diets 1-3, respectively) and either 0 ppm (Diets 1-3) or 40 ppm boron (Diets 4-6; Diets 4-6 were Diets 1-3, respectively, plus boron) as sodium tetraborate decahydrate as a possible mitigant. In this …

Effects Of Dietary Amino Acid Supplementation On Measures Of Whole-Body And Muscle Protein Metabolism In Aged Horses, Christine M. Latham

Theses and Dissertations--Animal and Food Sciences

Sarcopenia is a condition that is most common in aged animals, and is characterized by the loss of skeletal muscle mass and integrity, and can lead to physical disability and poor quality of life. Since skeletal muscle protein synthesis can be limited by the availability of amino acids, supplementation of limiting amino acids to ameliorate the progression of sarcopenia has become a topic of interest in companion animal research. Although there is some data to support the idea that amino acid supplementation improves maintenance of muscle mass in aged horses, the cellular mechanisms behind that improvement have yet to be …

Towards Determination Of The Threonine Requirement Of Yearling Horses Fed Varying Dietary Compositions Using The Indicator Amino Acid Oxidation Method, Kelsey M. Smith

Theses and Dissertations--Animal and Food Sciences

The amino acid requirements of growing horses are currently unknown, and studies suggest that threonine is a limiting amino acid in common horse diets. Thus, the objective of this study was to determine the threonine requirement of growing horses fed two different forage to concentrate ratios using the indicator amino acid oxidation method. The study consisted of a high concentrate phase (HC; 60% concentrate and 40% forage) and a high forage phase (HF; 25% concentrate and 75% forage). Within each phase, 6 female yearling Thoroughbred horses were randomly assigned each of 6 dietary treatments in a 6 x 6 Latin …

Relationships Between Behavioral Measures And Productivity In Finishing Beef Cattle, Jasmyn Mimiko

Theses and Dissertations--Animal and Food Sciences

The relationship between measures of temperament, growth performance, and social hierarchy in finishing beef cattle were explored in two experiments. In experiment 1, high OCS (objective chute score) steers had periods of significantly higher ADG (P < 0.01), but OCS had no relationship with dominance ranking (P > 0.47). Conversely, slow exit velocity (EV) correlated with higher ranking (P ≤ 0.06), but EV had no relationship with performance (P > 0.37) in a competitive environment. Rank showed no relationship with performance (P > .58). In experiment 2, steers with fast EV had periods of decreased growth (P ≤ .06), intake (P ≤ .06), and gain:feed (G:F; P = 0.02). There were no interactions between …

Using The Indicator Amino Acid Oxidation Technique To Study Threonine Requirements In Horses Fed Different Feed Compositions, Chanhee Mok

Theses and Dissertations--Animal and Food Sciences

Threonine has been reported to be the second limiting amino acid in typical equine diets, but its actual requirement has not been determined in horses. The indicator amino acid oxidation (IAAO) method has been successfully used for evaluating amino acid metabolism and requirements in animals and humans. The objective of this research was to use the IAAO method to estimate threonine requirements in mature horses fed two different feed compositions. In the first study, 6 Thoroughbred mares (4 – 16 years old) received each of 6 levels of threonine intake in a high concentrate diet, in a randomly determined order. …

The Effect Of Dietary Nucleotides In Sow And Nursery Piglet Diets On Reproduction, Growth, And Immune Response, I-Fen Hung

Theses and Dissertations--Animal and Food Sciences

The objectives of these studies was to evaluate the effects of nucleotide (NT) supplementation of sow diets during late gestation and lactation and in nursery diets to elucidate the potential value of nucleotides for a variety of biological responses.

The studies conducted in the university research facilities showed that supplying nucleotides to sow diets during late gestation and throughout lactation had no effect on routinely measured reproductive responses or piglet growth postweaning. Nucleotides in the nursery diet had no effects on growth performance and intestinal morphology. However, the LPS-challenged pigs that consumed NT diets tended to lose less weight and …

Steroid-Dependent Regulation Of The Oviduct: A Cross-Species Transcriptomal Analysis, Katheryn L. Cerny

Theses and Dissertations--Animal and Food Sciences

Reproductive success depends on a functional oviduct for gamete storage, maturation, fertilization, and early-conceptus development. The ovarian-derived sex steroids estradiol and progesterone are known to affect functionality of the oviduct. Advances in microarray and NanoString technology allow for gene expression analysis to increase understanding of processes critical for fertility. Studies were conducted to investigate mechanisms regulating oviductal function in cattle and mice by using the Bovine Gene 1.0 ST array and the Mouse Gene 430-2.0 arrays (Affymetrix Inc., CA), respectively.

For the first study, oviducts were collected from heifers assigned to luteal or follicular phase groups. In the second study …

Gestational Form Of Supplemental Selenium (Se) Affects Steroidogenic Gene Expression In The Newborn Calf Testis, Stefani R. Garbacik

Theses and Dissertations--Animal and Food Sciences

Selenium (Se) is an important trace mineral in the diet of cattle. Our objective was to determine whether the form of supplemental Se fed to the dam would affect the expression of genes regulating steroidogenesis in the newborn testis. Twenty-four Angus-cross cows were assigned randomly (n=8) to individual ad libitum access of a mineral mix containing 35 ppm of Se supplied as sodium selenite (inorganic, ISe; Prince Se), Sel-Plex (organic, OSe; Sel-Plex, Alltech) or a 50/50 mix of ISe/OSe (MIX) 4 months prior to breeding and throughout gestation. All male calves were castrated within 2 days of birth and total …

An Assessment Of Two Feed Additives To Improve Feed Utilization In Pigs, Amanda Shaw Thomas

Theses and Dissertations--Animal and Food Sciences

Three experiments were conducted to assess the efficacy of including selected feed additives in the diet of weaning and grow-finish pigs. Experiment 1 utilized 24 crossbred grow-finish pigs and measured the effect of added EHY on DM, N, and energy digestibility. There were no differences in DM, Energy, and N digestibility between diets 1 through 4. Experiment 2 utilized a total of 36 crossbred pigs [18 barrows, 18 gilts] in order to determine if preference would be shown when presented with naturally-contaminated corn. There were three dietary comparisons, Control vs Diet 2 (Comparison 1), Control vs Diet 4 (Comparison 2), …

Effect Of Direct-Fed Microbials And Monensin On In Vitro Rumen Fermentation, Sheryl Wingard

Theses and Dissertations--Animal and Food Sciences

The impact of supplying a mixed culture of lactate producing bacteria on in-vitro rumen fermentation of forage- (Experiment 1) and concentrate- (Experiment 2) based diets in the presence and absence of monensin was explored. In experiment 1, interactions between DFM and MON were absent (P>0.10) for gas production and fermentative end products. Gas production and fermentative end products were unaffected by DFM alone (P>0.10). Monensin decreased (P<0.001) CH₄ and NH₃ production, rate and total gas production, as well as total VFA concentration and molar proportions of acetate and butyrate. However, MON increased (P<0.001) proportions of propionate, valerate, isobutyrate and isovalerate. Independently, DFM and MON increased (P<0.001) end point pH. In experiment 2, DFM x MON interactions or tendencies (P=0.07, P<0.01, P<0.01) were present, DFM effects were abated by MON, for rate, total gas production and total VFA concentrations. Acetate:propionate ratio was decreased (P<0.01) with MON and was unaffected by DFM. Ammonia-N concentration was increased (P<0.01) by DFM and unaffected (P=0.75) by MON. Both DFM and MON treatment increased (P<0.01) ruminal pH levels. These studies suggest the effects of DFM and MON of in-vitro fermentation are …

Evaluating Dietary Amino Acid Adequacy In Horses Using Isotopic Techniques, Sara L. Tanner

Theses and Dissertations--Animal and Food Sciences

Little is known about amino acid (AA) requirements in horses despite muscle mass accretion being of importance to an athletic species. Isotope methods for determining AA requirements and whole-body protein synthesis (WBPS) had not been previously used in growing horses. The first study herein was the first to apply isotope methods to determine WBPS in growing horses. In the study, weanling colts received two different levels of crude protein. Whole-body protein kinetics indicated that WBPS was greater when the weanlings were fed the diet with a greater crude protein content (P<0.05). The second study sought to determine a lysine requirement for yearling horses using the indicator AA oxidation (IAAO) method. Despite using six dietary levels of lysine; three above and three below the current recommendation, no breakpoint could be determined. Phenylalanine kinetics were not affected by lysine level (P>0.05), but plasma lysine increased linearly with lysine intake …

Modeling Digestibility And Rate Of Passage In Horses, Tayler L. Hansen

Theses and Dissertations--Animal and Food Sciences

Horses consume large amounts of fiber in their diet, which may affect digestibility and digesta rate of passage. The objective of these studies was to assess the effects of diet composition on digestibility and rate of passage in horses using mathematical models. Using previously published data, forage dry matter digestibility (DMD) was related to forage neutral detergent fiber (NDF) concentrations and crude protein (CP) concentrations (DMD = 66.1178 – 0.3410*NDF + 0.6356*CP, DM basis; P < 0.001). In a second experiment, horses were fed diets formulated to have high fiber (HF, n= 3; NDF = 55.3%, CP = 11.8%) or low fiber (LF, n = 3; NDF = 40.5%, CP = 13.3%) concentrations. The LF treatment had greater DM, organic matter, and gross energy digestibilities (P < 0.05), whereas the HF treatment had greater NDF digestibility (P < 0.05). Mathematical models were useful to determine mean retention time (MRT) and there were no differences between model MRT and algebraic MRT, or treatment. Some compartmental parameters were different between treatments (P < 0.05), indicating that dietary fiber may alter some components of digesta passage in horses.

Effect Of Dietary Exposure To Ergot Alkaloids On Contractility Of Bovine Mesenteric Vasculature And Rumen Motility, Amanda M. Egert

Theses and Dissertations--Animal and Food Sciences

Endophyte-infected (E+) tall fescue grass has been associated with fescue toxicosis, a costly syndrome characterized by poor cattle performance and health resulting in significant production losses. The fungal endophyte produces ergot alkaloids, which help the grass thrive in poor conditions but are toxic to mammals. A number of symptoms of fescue toxicosis can be related to vasoconstriction of bovine core, peripheral, and foregut vasculature. The first part of this series of experiments demonstrated ergot alkaloids were also vasoactive in midgut vasculature, with the exception of lysergic acid. Additionally, prior dietary exposure to ergot alkaloids decreased the contractile response of mesenteric …

Use Of Mtb-100tm, Provided Through A Mineral Mix, To Reduce Toxicity When Lactating Beef Cows Graze Endophyte-Infected Tall Fescue, Melanie E. Hoar

Theses and Dissertations--Animal and Food Sciences

Two experiments were conducted at the University of Kentucky, Eden Shale Farm, Owenton, KY to evaluate the use of MTB-100^TM (Alltech, Inc., Nicholasville, KY) to alleviate the symptoms of fescue toxicity when lactating Angus x Beefmaster cows and their calves grazed endophyte-infected KY-31 tall fescue. Experiment 1 provided a carbohydrate based toxin adsorbent, MTB-100^TM, ad libitum in a commercial mineral supplement to project a daily consumption rate of 0, 20 or 40 g of MTB-100^TM per cow. Cows were weighed, assigned a body condition score (BCS) and hair coat score (HC), rectal temperatures were recorded and …

Effect Of Estradiol Supplementation On Blood Estradiol And Metabolite Levels, And Hepatic Protein Expression, In Growing, Mature, And Senescent Beef Cattle, Edwena D. Miles

Theses and Dissertations--Animal and Food Sciences

Estradiol (Compudose®, COM) implants are extensively used in beef cattle production systems to alter body composition and feed efficiency. Little information exists about the physiological mechanisms affected by COM treatment in growing, mature, and senescent female cattle. Moreover, no reports describe the level of blood estradiol resulting from COM treatment. The effect of COM on levels of plasma estradiol and blood metabolites and proteins, and relative content of glutamine synthetase (GS) and other amino acid nitrogen-metabolizing enzymes in liver tissue, was studied using three experimental models relevant to cow-calf production regimens: senescent cows (Trial 1), young mature (young) versus senescent …

Effects Of Endophyte Infected Fescue Alkaloid Ingestion On Energy Metabolism, Nitrogen Balance, In Situ Feed Degradation, And Ruminal Passage Rates, Anne F. Koontz

Theses and Dissertations--Animal and Food Sciences

The decrease in productivity caused by fescue toxicosis has been estimated to cost the United States livestock industry more than $1 billion per year due to reduced growth and diminished reproductive efficiency. This goal of the research presented in this dissertation is to enhance the knowledge base concerning the underlying physiological changes that occur during fescue toxicosis that lead to reduced intake and weight gain in cattle.

As one of the factors associated with fescue toxicosis is a reduction in feed intake, achieving a consistent and adequate intake of toxins can be a complication. Results from experiment 1demonstrate that ruminal …

Phosphorus Digestibility And Phytate Degradation In Long Yearlings And Mature Horses, Ashley Fowler

Theses and Dissertations--Animal and Food Sciences

Much of the phosphorus (P) in grain-based concentrates fed to growing horses is in the form of phytate-P. Little is known about the ability of young horses to degrade phytate-P or whether age affects mineral digestion in horses. The objective of this study was to examine the effect of age on P, calcium (Ca), and magnesium (Mg) digestibility and phytate-P degradation. Four long yearling geldings and 4 mature geldings were fed a diet of alfalfa cubes, timothy cubes and a pelleted concentrate. The diet contained 0.28% total P and 17.4% of that P was in the phytate form. There was …

Evaluation Of The Effects Of Vitamin K On Growth Performance And Bone Health In Swine, James S. Monegue

Theses and Dissertations--Animal and Food Sciences

The role of vitamin K in the blood clotting cascade has been well documented. Vitamin K has recently been implicated in improving bone health. The current studies were conducted to determine the effects of vitamin K in diets with and without mycotoxin contaminated corn on growth performance, bone characteristics, and related blood metabolites in pigs from weaning to market. Menadione sodium bisulfite complex (MSBC, 33% vitamin K) was chosen as the source of supplemental vitamin K because it is the most common form fed to swine. Vitamin K was tested at 0, 0.5, and 2.0 ppm in a corn-soybean meal …

Detection Of Antibodies Against Parascaris Equorum Excretory-Secretory Antigens, Steffanie V. Burk

Theses and Dissertations--Animal and Food Sciences

Parascaris equorum is a nematode parasite that infects young horses, sometimes causing unthriftiness, respiratory signs, or intestinal impaction in severe cases. Infection can be diagnosed by detection of eggs in feces, but this is only possible after the worms are fully mature. The goal of this study was to develop an antibody-based test for prepatent diagnosis of P. equorum infection. To produce western blot (WB) antigen, P. equorum larvae were cultured for collection of excretory-secretory antigens (ESA). Sera from 18 pregnant broodmares, their subsequent foals, and a group of 12 older mares and geldings were analyzed. In order to check …

The Effect Of Pituitary Pars Intermedia Dysfunction On Protein Metabolism And Insulin Sensitivity In Aged Horses, Laurel M. Mastro

Theses and Dissertations--Animal and Food Sciences

Equine pituitary pars intermedia dysfunction (PPID) typically occurs in horses older than 15 years of age and is characterized by hair coat abnormalities, muscle atrophy and decreased insulin sensitivity. The first objective of this research was to compare the rate of whole body protein metabolism and relative abundance of key factors in the signaling pathways associated with muscle protein synthesis and protein breakdown in response to feeding in Control and PPID horses. No differences (P > 0.05) were seen between the PPID and Control groups in whole-body protein metabolism or post-prandial activation of the muscle signaling pathways regulating skeletal muscle protein …

The Effects Of Slow Release Urea On Nitrogen Metabolism In Cattle, Vaughn B. Holder

Theses and Dissertations--Animal and Food Sciences

The objective of this research was to investigate the effects of slow release urea on N metabolism in cattle. The ruminal behavior of Optigen®II and the effect of basal diet on the in situ degradability of urea and Optigen®II were evaluated. The effect of slow release urea and its interaction with degradable intake protein (DIP) level in the diet on N retention and excretion was evaluated utilizing 8 Holstein steers in a 4 x 4 Latin square experiment. In addition, the effect of slow release urea and DIP level on ruminal and systemic urea kinetics was evaluated using stable isotope …

Influence Of Dietary Selenium Supplementation Form On Hepatic Transcriptome Profiles Of Maturing Beef Heifers, Zhi Zhang

Theses and Dissertations--Animal and Food Sciences

Our objective was to know how the hepatic transcriptome expression of growing beef (Angus-cross) heifers (0.5 kg gain/day) was affected by the feeding of different sources of dietary (3 mg/day) Se supplements: inorganic Se (ISe, sodium selenite), organic (OSe, Sel-Plex®), or a blend (1.5 mg:1.5 mg) of ISe:OSe (Mix), compared to the adequate but non-Se supplemented “Control”. The biopsied hepatic tissues of these four groups heifers collected at day 168 (when liver Se assimilation had stabilized) after supplements of Se, was subjected to the microarray analysis to assess Se treatment effects.

The results suggest that there were clear differences in …