Life Sciences Commons^™

Beef Production Systems From Weaning To Slaughter In Western Nebraska, Cynthia Morris, Ivan G. Rush, Burt Weichenthal, Brad Van Pelt

Nebraska Beef Cattle Reports

Numerous alternatives exist for feeding and managing weaned medium-frame steers to slaughter. Efficiency of beef production includes the total growing and finishing period. Often economics of production only considers a single part of the production systems. As a consequence one segment of the industry may make decisions based on maximum profit while they own or manage an animal that may adversely effect the profit of a subsequent owner. possibly causing overall economic efficiency to be lowered. For example, cost per pound of gain is usually lower when calves are wintered at a relatively fast rate of gain and consequently feedlot …

Gelatinized High Added-Water Beef Connective Tissue Protein Gels As Potential Water Binders, Wesley N. Osburn, Roger W. Mandigo

Nebraska Beef Cattle Reports

Research in fat reduction of processed meats has recognized problems associated with removal of fat: toughness, rubbery texture, lack of flavor and juiciness, and a darker color. Regardless of the importance of diet and health issues to consumers, low-fat products will not be purchased if they have unacceptable palatability or appearance. Current technologies for fat replacement include the addition of water, protein-based, carbohydrate-based, or synthetic compounds, alone or in combination. The addition and retention of water by these fat replacers is effective in improving the palatability attributes of low-fat meat products. Beef connective tissue (BCT), a byproduct of desinewing operations, …

Cellulose Adherence Factors In Ruminococcus Albus, Randall Pegden, Mark Morrison

Nebraska Beef Cattle Reports

Grazing and forage-fed animals depend upon the rumen microorganisms’ ability to breakdown polysaccharides present in the leaf and stems of plants. The rate and extent of this breakdown has a major impact on animal nutrition, therefore understanding the mechanics of this process offers the potential to optimize and further improve animal performance. The limited published studies to-date suggest that: 1) colonization and adherence by some rumen bacteria are specific in nature and: 2) adherence can be modified by nutrients and growth conditions, such as ruminal pH. Better understanding and future improvements of fiber digestion in the rumen will be afforded …

Evaluation Of Levels Of Wet Corn Gluten Feed And Addition Of Tallow, Chris Richards, Rick Stock, Terry J. Klopfenstein

Nebraska Beef Cattle Reports

Wet corn gluten feed (WCGF) is a byproduct of the wet corn milling industry and contains 90 to 110% of the relative energy value of corn in finishing diets. Wet corn gluten feed (Cargill) contains higher levels of protein (20%). phosphorus (1.0%). and potassium (1.2%) than corn. Wet corn gluten feed is higher in lumen degradable (80 vs 40%) and lower in escape protein (20 vs 60%) when compared with corn. The lipid contents of WCGF and corn are similar, at 5%.

Wet distillers byproducts (wet grains and thin stillage) are byproducts of the dry milling industry and have been …

Effects Of Bovatec, Rumensin Or Gainpro Fed To Yearling Summer Grazing Steers, Ivan G. Rush, Burt Weichenthal, Brad Van Pelt

Nebraska Beef Cattle Reports

Studies of beef production systems often indicate profitability can be increased in calf growing and feeding programs if yearling cattle are grazed at least during part of the growing phase. If yearling cattle are grazed on summer range, it is important that the summer gain be as efficient and economical as possible. The use of implants and ionophores can improve gain in grazing cattle. A feed additive, bainbermycins (GainPro™), has been released for the purpose of improving weight gain in cattle, especially in those consuming high roughage diets. Data from practical grazing conditions are limited with bambermycins so the objective …

Feeding Value Of Light-Test Weight Corn For Growing And Finishing Steers, Ivan G. Rush, Burt Weichenthal, Brad Van Pelt

Nebraska Beef Cattle Reports

When a corn growing season is not long or warm enough for corn to reach full maturity, the test weight can fall substantially below the standard. Currently the top market price is based on No. 2 corn, which in the U.S. is 54 lb per bu. Most grain dealers and beef feedlot operators will discount the corn price by increments as test weights fall below the standard U.S. No. 2, indicating that feed value is less. However. feeding trials over the years with light-test weight corn in poultry and swine diets and with grain sorghum fed to cattle have generally …

Roughage Source And Particle Size In Finishing Diets, Drew Shain, Rick Stock, Terry J. Klopfenstein, Mark Klemesrud

Nebraska Beef Cattle Reports

When compared to an all concentrate diet, roughage addition (5 to 15% of diet DM) stimulates intake, chewing, rumination and possibly particulate and liquid outflow from the rumen. Roughage addition. therefore. reduces acidosis by diluting concentrate intake and/ or increasing salivation and buffering capacity of the rumen.

Alfalfa hay is a commonly fed roughage source. If the use of the fiber fraction within alfalfa roughage is to simply dilute concentrate intake and help prevent acidosis, then any fiber source fed at a similar NDF level should respond similarly to alfalfa hay.

Particle size plays a major role in determining ruminal …

An Enzyme-Microbial Feed Product For Finishing Steers, Burt Weichenthal, Ivan G. Rush, Brad Van Pelt

Nebraska Beef Cattle Reports

The MSE feed product contains multiple enzymes plus four strains of bacteria, two strains of yeast and three strains of fungi. The bacteria were three Lactobacillus acidophilus cultures and one strain of Bacillus subtilis; the yeasts were three strains of Saccharomyces cerevisiae; and the fungi were two strains of Aspergillus oryzae and one of Aspergillus niger. Potential benefits for feeding MSE to finishing beef cattle could be improvement in daily gain and fee utilization. Thus a feedlot trial was designed to compare MSE to an ionophore-antibiotic combination often fed to finishing cattle on a high grain diet to improve feed …

Characterization Of Ammonia Utilization By Prevotella Ruminicola B1 4, Zezhang Wen, Mark Morrison

Nebraska Beef Cattle Reports

P. ruminicola is a predominant member of the rumen microflora, and in addition to its important role in fiber digestion, it is one of the major proteolytic bacteria from the rumen. It is capable of using both large peptides and ammonia as its nitrogen source, but not free amino acids, small peptides. and other low molecular weight N compounds. Also. prior growth with peptides appears to inhibit ammonia assimilation. and results in fermentation uncoupled from microbial growth. so called “energy spilling”.

For the great majority of grazing ruminants. ammonia is the major N source in the rumen. and it is …

Use Of Cell Culture To Study Muscle Growth In Beef Cattle, Timothy Woods, Carol Smith, Steven J. Jones

Nebraska Beef Cattle Reports

Muscle growth is the primary objective of meat animal livestock producers and represents a major source of amino acids and energy within the animal. Endogenous and exogenous factors that impinge on muscle cell development may influence the animal throughout its life cycle. In the adult animal, treatment with hormones, such as anabolic steroids or insulin, can affect muscle metabolism. Attempting to determine a compound's effects on muscle cell development and metabolism can be obscured in animal trials, since other organs and tissues are altering the environment.

Muscle cell culture provides a research tool to determine the direct effects of a …

Evaluation Of Animal Byproducts For Escape Protein Supplementation, Daniel Herold, Terry J. Klopfenstein, Mark Klemesrud

Nebraska Beef Cattle Reports

Blood meal, meat and bone meal. and feather meal are high in escape protein, relative to oil meals and forages. and increase performance when included in forage-based diets sufficient in rumen degradable protein. Two factors that influence the nutritive value of animal byproduct meals are processing conditions and raw materials.

Renderers apply heat to drive off moisture. extract fat. and eliminate bacterial contamination from animal tissues. This cooking also denatures proteins. creating cross links and insoluble bonds within and between protein chains: enhancing resistance to microbial degradation in the rumen. However. processing at very high temperatures can limit the extent …

Topographically Specific Effects Of Elf-1 On Retinal Axon Guidance In Vitro And Retinal Axon Mapping In Vivo, Masaru Nakamoto

Biology Faculty Publications

Topographic maps, which maintain the spatial order of neurons in the order of their axonal connections, are found throughout the nervous system. In the visual retinotectal projection, ELF-1, a ligand in the tectum, and its receptors in the retina show complementary gradients in expression and binding, indicating they may be positional labels for map development. Here we show that ELF-1 acts as a repellent axon guidance factor in vitro. In vivo, when the tectal ELF-1 pattern is modified by retroviral overexpression, retinal axons avoid ectopic ELF-1 patches and map to abnormally anterior positions. All these effects were seen on axons …

A Potential Understory Flora For Oak Savanna In Iowa, Karl T. Delong, Craig Hooper

Journal of the Iowa Academy of Science: JIAS

Oak savanna occurred in Iowa until the time of settlement and then was degraded rapidly. There were no scientific studies of savanna prior to, or after, settlement, and now no high-quality examples exist within the state. To identify those vascular plants adapted to live in the understory of savanna we examined regional and local flora for species that occurred in both prairie and broken woodland, and for species that occurred m both openings and forest. We then compiled a detailed description of the ecological range of habitats for each of these species. We identified 252 species (39 graminoids, 183 forbs, …

Current Status Of The Plains Pocket Mouse, Perognathus Flavescens, In Iowa, Gregory M. Wilson, John B. Bowles, Justin W. Van Zee

Journal of the Iowa Academy of Science: JIAS

Published and unpublished accounts of the plains pocket mouse (Perognathus flavescens) were utilized to document the existence of extant populations and to summarize and report additional data about the biology of this state endangered Iowa species. Populations of P. flavescens exist in western (Harrison, Monona, and Plymouth counties) and extreme eastern (adjacent portions of Louisa and Muscatine counties) Iowa, the latter of which represents the eastern-most record for the species in North America. In addition, we document a new locality for P. flavescens from the interior of the state (Benton County). All known populations of P. flavescens in Iowa occur …

An Annotated Checklist Of The Spiders Of Northwestern Iowa And The Loess Hills Of Western Iowa, Barbara J. Abraham

Journal of the Iowa Academy of Science: JIAS

Spiders were collected by the author from various habitats in 16 counties of northwestern Iowa and the loess hills of western Iowa during the summers of 1985 and 1990-1992. Additional donated specimens from the same region in 1981and1989 were identified by the author. Twenty-three families, 92 genera and 184 species have been identified.

Front Matter

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

Geochemistry Of Buried Midcontinent Rift Volcanic Rocks In Iowa: Data From Well Samples, Karl E. Seifert, Raymond R. Anderson

Journal of the Iowa Academy of Science: JIAS

We analyzed welt cores and cuttings from deep wells into Precambrian igneous rocks from five separate pacts of the buried Midcontinent Rife System in Iowa for major and trace elements. A total of 21 samples, 9 cores and 12 cuttings, were analyzed for trace elements by instrumental neutron activation analysis (INAA) and 11 of these, 9 cores and 2 cuttings, were analyzed for major elements by inductively coupled plasma (ICP) analysis.

Book Review - The Unnatural Nature Of Science: Why Science Does Not Make (Common) Sense, David Lopatto

Journal of the Iowa Academy of Science: JIAS

A distinguished psychologist once wrote that if you wished to understand the history of scientific thought you need a psychologist at your elbow. Lewis Wolpert, Professor of Biology at University College in London, has taken that sentiment further. It seems that if you wish to understand the difference between scientific and nonscientific thinking you should delve deeply into the literature of cognitive psychology. For natural thinking, "ordinary, day-to-day common sense will never give an understanding about the nature of science." Instead, the trained scientist engages in unnatural (i.e., counterintuitive) thinking about a word that defies ordinary experience. In order to …

Index For Volume 103

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

Back Cover

Journal of the Iowa Academy of Science: JIAS

No abstract provided.

Wood And Stem Anatomy Of Menispermaceae, Sherwin Carlquist

Aliso: A Journal of Systematic and Floristic Botany

Qualitative and quantitative data are presented for 17 collections of 15 species representing 14 genera. One species is a shrub (Cocculus laurifolius), one a subshrub (C. trilobus), and the remainder are lianas. Successive cambia are analyzed with respect to ontogeny and histology of products. Whether any Menispermaceae may or may not plesiomorphically lack successive cambia would require a more extensive survey of the family. Apomorphic absence of successive cambia is likely for species with subshrub growth forms (Cocculus trilobus, Menispermum canadense L.). Lianoid Menispermaceae share the following features: successive cambia, wide vessels, wide rays, …

A Revision Of The Euphorbia Dioscoreoides Complex (Euphorbiaceae), Victor W. Steinmann

Aliso: A Journal of Systematic and Floristic Botany

No abstract provided.

Does The Monocot Mode Of Leaf Development Characterize All Monocots?, Geeta Bharathan

Aliso: A Journal of Systematic and Floristic Botany

Patterns of early leaf development in monocots are analyzed in a phylogenetic context. Recent developmental and phylogenetic studies enable this reevaluation of the leaf base model of the developing monocot leaf. Two questions are addressed: a) is the presence of the Vorläuferspitze (fore-runner tip) invariably correlated with development of the lamina from the lower leaf zone? and b) was the ancestral monocot characterized by the leaf base mode of development? Scanning electron microscopic observations are made of young primorida using the mold and cast method. These data are combined with data from the literature and examined in a phylogenetic context …

Androgen Receptors In The Hippocampus: Localization, Autoregulation, And Modulation Of Gene Expression In The Adult Male Rat, Janice E. Kerr

Dissertations

No abstract provided.

Differential Black Walnut Growth On A Recommended Soil Map Unit: Investigation Of Related Soil Chemical And Physical Properties, David C. Ditsch, Jeff Stringer, D. Mcintosh

Agronomy Notes

Black walnut (Juglans nigra L.) is one of the best known and most valuable trees in Kentucky. However, due to its high value, the species has been aggressively harvested from natural stands, creating a limited supply of quality black walnut trees. Many landowners recognize this as an investment opportunity and have placed small tracts of unused land into black walnut production.

Als Resistant Smooth Pigweed In Western Kentucky, R. E. Schmenk, Michael Barrett, William W. Witt

Agronomy Notes

Pigweeds The pigweed, or Amaranthus, family contains some of the most commonly occurring weeds of midwest agriculture. Species from this family that occur in Kentucky include smooth pigweed (Amaranthus hybridus, most common), tumble pigweed, prostrate pigweed, spiny amaranth,Palmer amaranth,common waterhemp, and tall waterhemp. Research has shown that some pigweed species respond differently to various herbicides, therefore, proper identification is necessary to achieve acceptable control. Pigweed identification in early stages of seedling growth can be difficult because the distinguishing physical characteristics do not appear until plants are mature or have produced seed. Also, some pigweed species may cross-pollinate to …

Effect Of Boron Fertilization On Alfalfa, Monroe Rasnake, Garry D. Lacefield

Agronomy Notes

The need for boron (B) fertilization of alfalfa has been known for many years. An annual application of 1.5 to 2.0 ·pounds of elemental B per acre on alfalfa has been the general recommendation of the University of Kentucky's, Department of Agronomy for at least 20 years. Most states surrounding Kentucky have similar recommendations; however, some indicate that B needs to be applied only once every two years. There has been very little recent research to verify the need for B on alfalfa.

Applications Of An Ecophysiological Model For Irrigated Rice (Oryza Sativa)- Echinochloa Competition, John L. Lindquist, Martin Kropff

Department of Agronomy and Horticulture: Faculty Publications

A. simulation model of rice-barnyardgrass competition for light was used for two management applications. First simulations using47 weather data sets from four locations in Asia were conducted to evaluate the influence of weather variation on single year economic threshold densities of barnyardgrass. Second rapid leaf area expansion and leaf area index were evaluated as potential indicators of improved rice competitiveness and tolerance to barnyardgrass. Influence of weather variation on single year economic thresholds was small under the assumption that competition was for light only. Increasing early leaf area expansion rate reduced simulated barnyardgrass seed production and increased single year economic …

Herpesvirus-Like Dna In Aids Kaposi’S Sarcoma In Argentina [Letter To The Editor], Carlos E. Sosa, Jorge A. Benetucci, Laura M. Sieczkowski, Anibal Vazquez, Xue-Lan Wen, Marianna Baum, Winslow Klaskala, William J. Harrington Jr., Charles Wood

Nebraska Center for Virology: Faculty Publications

First paragraph: Recently, Chang et al., using a new molecular biology technique termed Representational Difference Analysis, found herpesvirus-like DNA (KSHV) in AIDS patients with Kaposi’s sarcoma (KS). The presence of KSHV DNA sequences suggests that a new human herpesvirus may be associated with KS. The 5′ end of the 1853-bp flanking region of KSHV (nucleotides 1 to 607) was found to have 66 and 67% homologies to the corresponding regions of the major capsid protein gene of Herpesvirus Saimiri (ORF25) and Epstein Barr virus (BcLF1), respectively, both members of the gammaherpesvirus family. This finding is an important breakthrough, because a …

Regulation Of Beta-Glucosidase In Marine Bacteria, Dennis Stetter

HCNSO Student Theses and Dissertations

The following is a study of the regulation of production of a catabolic enzyme, beta-glucosidase, by isolated strains of marine bacteria. Catabolic enzymes transform organic matter to monosaccharides which are utilized as an energy source for growth by bacteria. The bacterial strains were isolated from the Gulf Stream off the coast of Florida, as well as from particulate matter collected from waters adjacent to the Florida coast.

The first section describes the preparation of a liquid medium using sterile saltwater supplemented with inorganic nutrients and a carbohydrate component. This medium allowed growth of marine bacteria under carbohydrate-limiting conditions. A solid …