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Full-Text Articles in Life Sciences

Evaluating Dietary Amino Acid Adequacy In Horses Using Isotopic Techniques, Sara L. Tanner Jan 2014

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 …


Effect Of Dietary Exposure To Ergot Alkaloids On Contractility Of Bovine Mesenteric Vasculature And Rumen Motility, Amanda M. Egert Jan 2014

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 …


Effect Of Direct-Fed Microbials And Monensin On In Vitro Rumen Fermentation, Sheryl Wingard Jan 2014

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 …


The Initial Phases Of A Consistent Pricing System That Reflects The Online Sale Value Of A Horse, Curran A. Prettyman Jan 2014

The Initial Phases Of A Consistent Pricing System That Reflects The Online Sale Value Of A Horse, Curran A. Prettyman

Lewis Honors College Capstone Collection

Horses are one of the most uniquely priced commodities. This document provides a solution to an industry-wide weakness of inconsistent pricing and confusion. In the following report, an evaluation of the industry flaw is presented, an econometric approach is described in full, and a solution is proposed using insight gained from a regression analysis. This report uses an econometric approach to determine the impact of hunter jumper horse qualities on internet sale prices. Data is compiled from bigeq.com for seventy-eight horses in the states of Illinois, Indiana, Kentucky, Michigan, and Ohio. A linear regression analysis for twelve variables establishes that …


Gestational Form Of Supplemental Selenium (Se) Affects Steroidogenic Gene Expression In The Newborn Calf Testis, Stefani R. Garbacik Jan 2014

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 Jan 2014

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), …


Evaluating The Effect Maturity On The Intake And Digestibility Of Switchgrass Hay Consumed By Beef Steers, David H. Davis Jan 2014

Evaluating The Effect Maturity On The Intake And Digestibility Of Switchgrass Hay Consumed By Beef Steers, David H. Davis

Theses and Dissertations--Plant and Soil Sciences

There has been increased interest in utilizing switchgrass (Panicum virgatum) as biomass. There are several challenges to developing this industry, and these have led to the potential use of switchgrass as hay for feeding beef cattle in Kentucky. The effect of increasing maturity on crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF) and nutritive values of switchgrass hay has been well documented, but few in vivo intake and digestibility trials have been conducted to assess this effect on animal performance when feeding beef cattle. Two in vivo intake and digestibility trials were conducted in 2011 …


Modulation Of Vaccine-Induced Responses By Anthelmintic Treatment In Ponies, Emily Rubinson Jan 2014

Modulation Of Vaccine-Induced Responses By Anthelmintic Treatment In Ponies, Emily Rubinson

Theses and Dissertations--Medical Sciences

Vaccines and anthelmintics induce an inflammatory response in equids. Since they are commonly given concurrently, it is practical to study any interaction between them. This study evaluated whether IVM and PYR would modulate the acute phase inflammatory response, the systemic gene expression of pro-inflammatory cytokines, and vaccine-specific titers induced by WNV, EHV, and KLH vaccines. Naturally-infected, yearling ponies were sorted by gender, then fecal epgs. They were randomly assigned to three treatment groups: IVM, PYR, and control. All ponies received vaccinations intramuscularly on days 0 and 29. Whole blood, serum, and plasma samples were collected 1, 3, and 14 days …


Modeling Digestibility And Rate Of Passage In Horses, Tayler L. Hansen Jan 2014

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.