Veterinary Medicine Commons^™

Effect Of Corn Residue Removal On Subsequent Crop Yields, Mary E. Drewnoski, L. Aaron Stalker, James C. Macdonald Donald, Galen E. Erickson, Kathy J. Hanford, Terry J. Klopfenstein

Nebraska Beef Cattle Reports

Two studies were conducted to evaluate the effects of corn residue harvest on subsequent crop yields. In a long-term study (16 years), cattle grazing corn residue in the spring (February to the middle of April) or the fall (November through January) slightly improved subsequent soybean yields and had no effect on corn yields in an irrigated field maintained in an annual corn-soybean rotation at Mead, Neb. In a five-year study, fall grazing (December through January) or baling of corn residue had no effect on subsequent corn grain yields in a field maintained in continuous corn production at Brule, Neb. These …

Effect Of Feeding Distillers Grains In Different Phases Of Production On The Fatty Acid Profile And Oxidation Of Frozen, Cooked Beef Links, Brandy D. Cleveland, Amy L. Redfield, James C. Macdonald Donald, Tommi F. Jones, Gary A. Sullivan

Nebraska Beef Cattle Reports

Lipid oxidation of cooked ground beef links made from cattle fed different diets and with different concentrations of added natural antioxidants was compared to evaluate product shelf life. Fatty acid composition was analyzed on raw lean, composite, and fat portions from each shoulder clod. Samples without antioxidants were the most oxidized, with no differences between other antioxidant concentrations throughout frozen storage. An increase in polyunsaturated fatty acids was found in beef when finished on modified distillers grains but did not result in increased oxidation. Therefore, the addition of natural antioxidants was effective at reducing oxidative rancidity regardless of animal diet.

A Basic Mechanism Of Beef Tenderization: Feeding Wet Distillers Grains Plus Solubles Contributes To Sarcoplasmic Reticulum Membrane Instability, Michael D. Chao, Katherine I. Domenech, Chris R. Calkins Calkins

Nebraska Beef Cattle Reports

Feeding wet distillers grains plus solubles (WDGS) could increase polyunsaturated fatty acid (PUFA) concentration in the sarcoplasmic reticulum (SR) membrane, thereby altering membrane integrity, resulting in more rapid post-rigor calcium leakage, greater enzyme activity and improved tenderness. Steers were finished on either 0% WDGS or 50% WDGS. Steaks from steers fed WDGS were more tender and had greater free calcium concentrations. Feeding WDGS also increased proportions of PUFA in SR membrane and altered SR lipid and phospholipid profiles. These findings suggest that feeding increased concentrations of WDGS in the finishing diet can possibly increase meat tenderness through the proposed mechanism.

Feeding Elevated Levels Of Corn Silage And Mdgs In Finishing Diets, Dirk B. Burken, Brandon L. Nuttelman, Curtis J. Bittner Bittner, Terry J. Klopfenstein, Galen E. Erickson

Nebraska Beef Cattle Reports

A finishing experiment evaluated substitution of corn silage and modified distillers grains with solubles (MDGS) in place of corn. The experimental arrangementwas a 2 X 2 + 1 factorial with diets containing 15 or 45% corn silage and 20 or 40% MDGS as well as a control containing 5% cornstalks and 40% MDGS. There were no interactions between corn silage and MDGS inclusion for carcass adjusted performance. As corn silage inclusion increased in the diet, there was a modest reduction in ADG and an increase in F:G. When MDGS inclusion was increased, ADG and F:G were improved. Cattle fed 40% …

The Effects Of Corn Price, Shrink, And Harvest Moisture On Corn Silage Economics, Dirk B. Burken, Terry J. Klopfenstein, Galen E. Erickson Erickson

Nebraska Beef Cattle Reports

Economic assumptions were applied to corn production to set corn silage prices for breakeven corn production, whether harvested for corn grain or corn silage. Price levels were used for the calculation of returns per finished steer as corn silage inclusion increased in finishing diets containing distillers grains. As corn price increased, the economics of feeding elevated concentrations of corn silage became more favorable. The economic importance of shrink and harvest moisture content were assessed. As corn price increases and the inclusion of corn silage increases, corn silage management decisions have greater economic importance.

Digestibility Of De-Oiled Modified Distillers Grains Plus Solubles In Forage-Based Diets, Meredith L. Bremer, Sarah J. Peterson, Adam L. Shreck Shreck, Galen E. Erickson, Terry J. Klopfenstein, James C. Macdonald

Nebraska Beef Cattle Reports

Over half of Nebraska’s ethanol plants are removing oil from distillers grains via centrifugation of the thin stillage constituent. Removing oil by this method does not impact intake or total tract digestibility in beef cattle growing diets. However, increasing the concentration of de-oiled distillers grains in the diet significantly improved intake and digestibility. Thus, concentration of distillers grain in the diet has a greater impact on total tract digestibility than the fat content in forage-based diets.

Feeding Value Of De-Oiled Wet Distillers Grains Plus Solubles Relative To Normal When Fed With Either Dry-Rolled Corn Or Steam-Flaked Corn In Beef Finishing Diets, Meredith L. Bremer, Marie E. Harris, Jake A. Hansen Hansen, Karla H. Jenkins, Matt K. Luebbe, Galen E. Erickson

Nebraska Beef Cattle Reports

A 128-day finishing study utilized 328 yearling steers to determine the effects of feeding de-oiled wet distillers grains plus solubles (WDGS) in dry rolled corn (DRC) or steam-flaked corn (SFC) diets relative to normal fat WDGS. No significant interactions were observed, but cattle fed DRC had greater DMI and were less efficient than those consuming SFC. Linear improvements in ADG and F:G were observed as concentration of de-oiled WDGS increased from 0 to 35%. Numerically cattle fed normal WDGS were more efficient than cattle fed de-oiled WDGS.

Response To Increasing Concentrations Of De-Oiled Modified Distillers Grains Plus Solubles In Beef Feedlot Diets, Meredith L. Bremer, Curtis J. Bittner, Dirk B. Burken Burken, Galen E. Erickson, James C. Macdonald

Nebraska Beef Cattle Reports

A 154-day finishing study, utilizing 378 calf-fed steers, was conducted to evaluate the response to feeding increasing concentrations of de-oiled modified distillers grains plus solubles (MDGS) on cattle performance and carcass characteristics. Two additional diets were fed to compare de-oiled MDGS to normal MDGS at either 15 or 30% inclusion. Increasing concentration of de-oiled MDGS in the diet resulted in a linear improvement in F:G. When comparing 30% de-oiled to normal MDGS, there was a tendency for 3.4% improvement in F:G for cattle fed normal MDGS diets over those fed de-oiled MDGS.

Comparison Of Wet Or Dry Distillers Grains Plus Solubles To Corn As An Energy Source In Forage-Based Diets, Nerissa A. Ahern, Brandon L. Nuttelman, Terry J. Klopfenstein Klopfenstein, James C. Macdonald, Galen E. Erickson

Nebraska Beef Cattle Reports

Four experiments were conducted comparing wet or dry distillers grains plus solubles to each other or to corn as an energy source in forage-based diets. Diets included dry distillers grains plus solubles, wet distillers grains plus solubles or dry-rolled corn, with sorghum silage, grass hay and supplement. Data were pooled to generate ADG at differing inclusions allowing energy value of wet distillers grains plus solubles to be calculated relative to dry-rolled corn. The energy value of distillers grains plus solubles fed at 15% of diet DM was 137% and fed at 30% of the diet DM was 136% relative to …

Effect Of Harvest Method On In Vitro Digestibility Of Corn Residues, Janessa J. Updike, Jana L. Harding, Terry J. Klopfenstein Klopfenstein, James C. Macdonald

Nebraska Beef Cattle Reports

New corn residue harvesting methods were evaluated to determine the impacts of altering the proportions of plant part that are composed in a round bale. In vitro techniques were used to assess the organic matter digestibility of corn residue bale harvested with different proportions of stalks, leaves, and husk. As husk comprised a greater proportion of the bale, digestibility appeared to increase when compared with a conventional bale of cornstalks.

Exogenous Administration Of Lipids To Steers Alters Aspects Of The Innate Immune Response To Endotoxin Challenge, Nicole C. Burdick Sanchez, Jeffery A. Carroll, Janet R. Donaldson, Joe O. Buntyn, Ty B. Schmidt

Department of Animal Science: Faculty Publications

This study examined the effects of increasing energy availability from both dextrose and lipid treatments on the proinflammatory response to LPS in Holstein steers. Steers were randomly assigned to one of three groups: saline at 0.5 ml/ kg body weight (Control) or 50% dextrose [0.5 ml/kg body weight (Dextrose) to mimic calm cattle’s response to LPS] administered immediately prior to LPS (0.5 mg/kg body weight at 0 h) or continuous lipid emulsion infusion from –1 to 6 h [Intralipid 20% (Baxter, Deerfield, IL USA); 0.5 ml/kg/hr (Lipid) to mimic temperamental cattle]. Concentrations of non-esterified fatty acids (NEFA) were greater in …

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 …

Sudden Death, Aortic Rupture In Horses, Literature Review, Case Studies Reported And Risk Factors, Abelardo Morales Briceño, Aniceto Mendez, Kimberly Brewer, Charlie Hughes, Thomas Tobin

Maxwell H. Gluck Equine Research Center Faculty Publications

Sudden deaths of horses in multiple equestrian disciplines have been attributed to acute and chronic respiratory and cardiovascular diseases. The aim of this study was to perform a review of aortic rupture in horses analyzing, case studies and assessing risk factors. The literature has reported a total of 137 cases of aortic rupture in horses for 28 years (1986-2014), with approximately five horses dying of aortic rupture per year. Histopathologically, there are observed discrete macroscopic degenerative changes in the intima layer only in the aorta. The histological evaluation in the beginning portion of the aorta of the heart evidenced degenerative …

Gastrointestinal Nematodes Of Ovis Aries In Eastern Cape, South Africa And An Evaluation Of Current Anthelmintic Procedures, Melyssa Rowell

Honors Theses and Capstones

Humans have known about helminth infections since ancient times. Today half of the human population is plagued by a nematode infection. Nematodes are responsible for billions of dollars in global crop damage annually and have had devastating effects on the global livestock industry. Due to the lack of a vaccine, and only a handful of approved classes of anthelmintics, nematode resistance has become a serious global phenomenon, and the South African commercial sheep industry has been one of the worst affected worldwide. The current study used fecal float parasitology to determine the nematode species found on a commercial sheep farm …

Show Horse Welfare, Melissa A. Voigt

Open Access Dissertations

In recent years there has been an increase in the public's attention to situations where trainers, owners, and handlers have compromised the well-being of show horses for the sake of winning. These situations may be due to training negligence or naivety of individuals working with the horse. Either way, due to these incidents, increasing pressure has been placed on the horse industry to address show horse welfare. The purpose of this research was to expound on the welfare of stock-type show horses through the perspective of those directly involved; considering the understanding of welfare, the value placed on welfare, and …

Relationship Between Heat-Labile Enterotoxin Secretion Capacity And Virulence In Wild Type Porcine-Origin Enterotoxigenic Escherichia Coli Strains, Prageeth Wijemanne, Jun Xing, Emil M. Berberov, David H. Francis, Rodney A. Moxley

School of Veterinary and Biomedical Sciences: Faculty Publications

Heat-labile enterotoxin (LT) is an important virulence factor secreted by some strains of enterotoxigenic Escherichia coli (ETEC). The prototypic human-origin strain H10407 secretes LT via a type II secretion system(T2SS). We sought to determine the relationship between the capacity to secrete LT and virulence in porcine-origin wild type (WT) ETEC strains. Sixteen WT ETEC strains isolated from cases of severe diarrheal disease were analyzed by GM1ganglioside enzyme- linked immunosorbent assay tomeasure LT concentrations in culture supernatants. All strains had detectable LT in supernatants by 2 h of culture and 1 strain, which was particularly virulent in gnotobiotic piglets (3030-2), had …

Temperatures Of Storage Areas In Large Animal Veterinary Practice Vehicles In The Summer And Comparison With Drug Manufacturers’ Storage Recommendations, Jeff D. Ondrak, Meredyth L. Jones, Virginia R. Fajt

School of Veterinary and Biomedical Sciences: Faculty Publications

Background: Large animal veterinarians carry drugs in their practice vehicles in storage areas that are not typically refrigerated. The most common upper limits of manufacturers’ storage temperatures for United States (U.S.)-approved non-refrigerated drugs are 25 or 30 °C. Because ambient temperatures in many locations in the U.S. exceed these temperatures during the summer, we measured storage area temperatures over 4 months in the summer of 2013 to evaluate the extent to which labeled storage temperatures are exceeded.

Methods: A convenience sample of 12 vehicles from 5 central Texas practices and 12 vehicles from 4 south central Nebraska practices was …

Nonlinear Hierarchical Models For Longitudinal Experimental Infection Studies, Michael David Singleton

Theses and Dissertations--Epidemiology and Biostatistics

Experimental infection (EI) studies, involving the intentional inoculation of animal or human subjects with an infectious agent under controlled conditions, have a long history in infectious disease research. Longitudinal infection response data often arise in EI studies designed to demonstrate vaccine efficacy, explore disease etiology, pathogenesis and transmission, or understand the host immune response to infection. Viral loads, antibody titers, symptom scores and body temperature are a few of the outcome variables commonly studied. Longitudinal EI data are inherently nonlinear, often with single-peaked response trajectories with a common pre- and post-infection baseline. Such data are frequently analyzed with statistical methods …

Reversible Downregulation Of Hypothalamic-Pituitary-Gonadal Axis In The Stallion With A Third-Generation Gnrh Antagonist, Gabriel Monteiro Davolli

Theses and Dissertations--Veterinary Science

The objectives of this thesis were: (1) to evaluate the downregulation of the stallion hypothalamic-pituitary-gonadal (HPG) axis by a GnRH antagonist (acyline) based upon endocrine, seminal, testicular and behavioral effects, and (2) to assess recovery after treatment. Stallions were treated for 50 days (n=4; 330µg/kg acyline q 5d) and controls (n=4) received vehicle alone. Stallions were assessed pre-treatment and for 72 days after last treatment. Treatment induced declines (p<0.05) in FSH, LH, testosterone (to castrate levels) and estrone sulfate. Gonadotropins and testosterone returned to control values within nine days and estrone sulfate by 14 days after treatment discontinuation. Acyline-treated stallions failed to respond with FSH, LH and testosterone increase after exogenous GnRH stimulation (25µg gonadorelin, IV) compared to pre-treatment and control stimulation. Total sperm numbers and motility were reduced in acyline-treated stallions, as well as total seminal plasma protein and testicular volume (p<0.05). Time to ejaculation was increased in acyline group (p<0.5). Testicular, sexual behavior and most seminal parameters regained normal levels within 72 days after treatment ceased. Sperm output of acyline-treated stallions was regained within seven months after ending treatment. Acyline reversibly suppressed the stallion HPG axis, thus has potential for treating the androgen-dependent Equine-Arteritis-Virus carrier state and as behavior modulator.

Glucocorticoid-Induced Chondrocyte Cytotoxicity At Doses Recommended For Intra-Articular Therapy In Horses, Wenying Zhu

Theses and Dissertations--Veterinary Science

Intra-articular glucocorticoid injections are commonly used to treat synovitis and osteoarthritis in horses. These agents are highly effective at relieving pain, swelling, and other symptoms of joint inflammation. The drugs also have therapeutic benefits by down regulating the expression of cytokines and protease enzymes that participate in the degradation of articular cartilage. However, detrimental effects on chondrocyte function and cell viability that is independent of osteoarthritis pathogenesis have been described and linked to glucocorticoid use. These side effects are both drug- and dose-dependent. This study tested the hypothesis that manufacture recommended dosage levels of methylprednisolone, betamethasone, and triamcinolone that are …

Uterine Artery Rupture, An Angiopathy Of The Reproductive System Of The Mare: Occurrence And Potential Effects, Ana G. Toro Mayorga

Theses and Dissertations--Veterinary Science

The intent of this research was to identify if the degenerative changes within arteries in the endometrium (endometrial angiopathies) correlate with degenerative changes in the uterine arteries and can be used as a predictor of increased risk for uterine artery rupture (UAR). With this objective specimens from 20 mares that died from uterine artery rupture and 21 control mares that died from unrelated causes were obtained from cases submitted to the University of Kentucky Veterinary Diagnostic Laboratory (UKVDL) over a two-year period. Postmortem specimens of each mare were collected from the left and right uterine arteries at the origin, bifurcation, …

Toxicity Of Leaf Extract Of Acer Spp. On Equine Erythrocytes, Bailey Katherine Dye

Undergraduate Honors Thesis Projects

Red maple toxicosis is a phenomenon that occurs in equines after the consumption of dried or wilted red maple (Acer rubrum L.) leaves. Within the erythrocytes, it causes hemolysis, methemoglobinemia, and Heinz body development. The toxic agent of red maple leaves has not yet been identified; however, the development of hemolytic anemia and methemoglobinemia in equines after ingestion of the leaves, suggests that the toxin is acting as a strong oxidant. Some studies have noted that not only are wilted red maples leaves toxic to equines, but that wilted leaves of other maple species may also be toxic. Therefore, …

The Role Of Herpes Simplex Virus Type 1 Glycoprotein K In Neuroinvasion And Immunopathogenesis Of Herpes Keratitis, Ahmad Saied

LSU Doctoral Dissertations

ABSTRACT Herpes simplex virus type 1 is a common neurotropic pathogen responsible for a multitude of human diseases ranging from mucocutaneous lesions, keratitis to life-threatening encephalitis. The hallmark of the HSV-1 life cycle is infection of sensory neurons, where the virus establishes a latent infection for the life of the host. Viral envelope glycoproteins play important roles in viral life cycle and virus-host interaction. Viral glycoproteins gK, gM, gE and the membrane protein UL11 have been shown to be important for virus assembly, egress and virus spread. To investigate the relative importance of each of gK, gM, gE and UL11 …

Comparative Genomic Studies Of Catfish And Zebrafish Strains Of Edwardsiella Ictaluri, Rui Wang

LSU Doctoral Dissertations

Edwardsiella ictaluri is a gram negative bacterium that is the causative agent of enteric septicemia of catfish. In 2011, this bacterium was identified as the causative agent of massive death in zebrafish populations in U.S. In this project, we found that isolates of E. ictaluri from zebrafish comprise a unique strain that differs from the type strain of E. ictaluri phenotypically as well as genetically. Also, strains of E. ictaluri from zebrafish are non-infectious in channel catfish Ictalurus punctatus by immersion. Here we sequenced the zebrafish strains of E. ictaluri LADL11-100 and LADL11-194 and compared the potential virulence genes in …

The Effects Of Prostatic Fluid On Functional Characteristics Of Cooled Canine Semen, Reto Fritsche

LSU Master's Theses

The objectives of this study were to investigate concentration dependent effects of canine prostatic fluid (PF) on in vitro seminal parameters of cooled canine semen. Sperm motility parameters, plasma membrane integrity and stability, acrosome integrity and DNA fragmentation were measured after the addition of 0%, 10%, 25%, or 50% PF to extended semen of fertile dogs. Assessments were made at 0 h pre-cooling, at 24, and 48 h of cooled storage (4 °C), and after freezing and thawing followed by incubation (37 °C) at 0, 4 and 24 h. Our hypothesis was that lower dilutions of canine semen with PF …

Supplementing Cow-Calf Pairs Grazing Smooth Bromegrass, Jason M. Warner, Annie J. Doerr, Galen E. Erickson Erickson, Rick J. Rasby, Terry J. Klopfenstein

Nebraska Beef Cattle Reports

A three-year study evaluated supplementing ethanol co-products mixed with low-quality forage to cow-calf pairs grazing smooth bromegrass as a method to replace grazed forage intake. Supplementing a 30:70 modified distillers grains plus solubles:cornstalks mixture reduced estimated grazed forage intake by approximately 40%. Doubling the stocking rate and supplementing did not impact cow or calf performance. A summer supplementation program designed to reduce grazed forage intake is a viable strategy for increasing stocking rate if forage for grazing is limited.

Effect Of Post-Weaning Management And Age At Weaning On Calf Growing And Finishing Performance, Jason M. Warner, Curtis J. Bittner, Karla H. Jenkins Jenkins, Rick J. Rasby, Terry J. Klopfenstein, Galen E. Erickson

Nebraska Beef Cattle Reports

The impact of post-weaning management system and calf age at weaning on growing and finishing performance was evaluated. During the growing phase, cattle in the fast-track system had improved intake, gain, and feed conversion. Although initial finishing weight was similar between systems, slow-track cattle had greater intake, gain, final body weight, and carcass weight. While the impact of age at weaning was negligible, the improvement in finishing performance for slow-track cattle demonstrates the value of different management systems.

Estimation Of British- And Continental-Specific Heterosis Effects For Birth, Weaning, And Yearling Weight In Cattle, Lauren N. Schiermiester, R. Mark Thallman, Larry A. Kuehn Kuehn, Matthew L. Spangler

Nebraska Beef Cattle Reports

Heterosis, assumed proportional to expected breed heterozygosity, was calculated for 6,834 individuals with birth, weaning, and yearling weight records from Cycle VII of the U.S. Meat Animal Research Center Germplasm Evaluation Program. Heterosis was further estimated by proportions of British x British (BxB), British x Continental (BxC), and Continental x Continental (CxC) crosses. Estimates of BxB, BxC, and CxC heterosis were significant for weaning and yearling weight. This study illustrated that differences among biological types exist and provide an opportunity to utilize specific breeds and exploit heterosis in a crossbreeding system to achieve production goals.

The Effects Of Source And Amount Of Nitrite On Quality Characteristics Of All-Beef Frankfurters, Eric Miller, Chad G. Bower, Amy L. Redfield Redfield, Gary A. Sullivan

Nebraska Beef Cattle Reports

In an effort to meet consumers’ demand for foods with more natural ingredients, processors have begun manufacturing meat products cured with natural nitrite sources. The objective of this study was to evaluate the quality characteristics of all-beef frankfurters cured with traditional or alternative sources of nitrite and using equivalent amounts of nitrite. Frankfurters cured with alternative sources of nitrite had a slightly darker, less red exterior and slightly more yellow interior than those containing sodium nitrite. No differences were observed for pH or water activity. Both curing methods can be used to manufacture all-beef frankfurters with similar characteristics when using …

Stocking Rate Effects On Forage Nutrient Composition In Early Summer Pastures, Jared V. Judy, Jacki A. Musgrave, L. Aaron Stalker Stalker, K. H. Jenkins, Terry J. Klopfenstein

Nebraska Beef Cattle Reports

Nebraska Sandhills upland range pastures were used to measure the effectsof stocking rate on forage nutrient content in early summer pastures. Stocked pastures had lower CP, in vitroorganic matter digestibility, forage availability, and higher NDF compared with ungrazed pastures. Clipped samples of current year growth had greater CP and in vitro organic matter digestibility than diet samples. Observed results indicate early season grazing decreasesdiet nutrient content and forage availability compared with ungrazed pastures, suggesting that cattle were consuming both current and previous year growth.