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Effects Of Varying Levels Of Cottonseed Hulls On Growth And Metabolic Indications Of Rumen Development Of Dairy Calves, Ryan Doescher 2010 Louisiana State University and Agricultural and Mechanical College

Effects Of Varying Levels Of Cottonseed Hulls On Growth And Metabolic Indications Of Rumen Development Of Dairy Calves, Ryan Doescher

LSU Master's Theses

A study was conducted to determine the effects of varying levels of cottonseed hulls on growth and metabolic indications of rumen development of dairy calves. Sixty-four Holstein calves (Heifers, n=40; Bulls, n=24) were randomly assigned to one of four dietary treatments which included calf starters containing no cottonseed hulls (control; C), 10% cottonseed hulls (10% CSH), 15% cottonseed hulls (15% CSH), or 20% cottonseed hulls (20% CSH). Calves were fed their respective treatments beginning on day 6 until day 56 of age. Body weights were measured at birth and biweekly thereafter until day 56 of age. Wither and ...


Laser-Assisted Zona Pellucida Hatching Of Frozen-Thawed In Vivo-Produced Bovine Embryos, Mindy Kaye Chiasson 2010 Louisiana State University and Agricultural and Mechanical College

Laser-Assisted Zona Pellucida Hatching Of Frozen-Thawed In Vivo-Produced Bovine Embryos, Mindy Kaye Chiasson

LSU Master's Theses

Incomplete zona hatching or failure of the zona to rupture compromises post-transfer embryo viability and conceptus development. Assisted hatching prior to the transfer of frozen-thawed bovine embryos has been proposed as a means to increase recipient pregnancy rates. The objective of this study was to determine if laser-assisted hatching would improve in vivo-produced frozen-thawed bovine embryo hatching and pregnancy rates. In Experiment I,II and III frozen direct-transfer embryos received either two a or three symmetrical rents at either 40% or 80% through the outer zona surface using the Hamilton Thorne XYClone® (Hamilton Thorne Biosciences) diode laser at 90% power ...


Cell Extract-Based Reprogramming Of Somatic Cells, Laura Whitney Coley 2010 Louisiana State University and Agricultural and Mechanical College

Cell Extract-Based Reprogramming Of Somatic Cells, Laura Whitney Coley

LSU Master's Theses

The differentiation potential of adult stem cells (ASC) has long been thought to be limited to cell lineages present in the organ from which they are derived; however, several studies have challenged this notion by demonstrating that some ASC exhibit a remarkably high degree of plasticity. Unlike terminally differentiated somatic cells, the less differentiated state of ASC can assume the functional phenotypes and expression profiles of cells unique to other tissues. The expansive repertoire of differentiation potential exhibited by ASC suggests these cells possess characteristics similar to pluripotent cells, including epigenomic regulatory pattern. Therefore, ASC may be better equipped for ...


Analysis Of Consumer Preferences Toward 100% Fruit Juice Packages And Labels, Tatiana Bonilla 2010 Louisiana State University and Agricultural and Mechanical College

Analysis Of Consumer Preferences Toward 100% Fruit Juice Packages And Labels, Tatiana Bonilla

LSU Master's Theses

A national web survey was used to collected data from 253 households in the United States. Choice-based conjoint analysis was used to investigate which packaging and labeling attributes U.S. consumers consider important when choosing 100% fruit juices, and to estimate their willingness-to-pay. The attributes were packaging material, nutritional and health claims, presence of organic ingredients and whether the product was produced locally. Factor analysis, cluster analysis and a median split technique were used to identify market segments based on consumer preferences, behavior, and lifestyles. Differences between the segments were analyzed. A conditional logit model was used to estimate relative ...


Off-Farm Labor Supply By Farm Operators And Spouses: A Comparison Of Estimation Methods, Mahesh Pandit 2010 Louisiana State University and Agricultural and Mechanical College

Off-Farm Labor Supply By Farm Operators And Spouses: A Comparison Of Estimation Methods, Mahesh Pandit

LSU Master's Theses

This thesis studies the off-farm labor supply decision of farm operators and their spouses in the United States. The data used in this study is from the Agricultural Resource Management survey, 2006. The objective of this study is twofold. First, to identify those factors that affect off-farm labor supply of farm operators and their spouses. In particular, this study investigates the impact of human capital of farm operators and spouses, personal, family, farm and location characteristics on labor allocation for on- and off-farm work. Empirical results indicate that farm operators’ and their spouses’ human capital are positively correlated with off-farm ...


Role Of Kappa-Opioid Receptors In The Effects Of Salvinorin A And Ketamine On Attention Behavior In Rats, Christina L. Nemeth, Tracie A. Paine, Joseph E. Rittiner, Cécile Béguin, F. Ivy Carroll, Bryan L. Roth, Bruce M. Cohen, William A. Carlezon Jr. 2010 Oberlin College

Role Of Kappa-Opioid Receptors In The Effects Of Salvinorin A And Ketamine On Attention Behavior In Rats, Christina L. Nemeth, Tracie A. Paine, Joseph E. Rittiner, Cécile Béguin, F. Ivy Carroll, Bryan L. Roth, Bruce M. Cohen, William A. Carlezon Jr.

Faculty & Staff Scholarship

Background: Disruptions in perception and cognition are characteristic of psychiatric conditions such as schizophrenia. Studies of pharmacological agents that alter perception and cognition in humans might provide a better understanding of the brain substrates of these complex processes. One way to study these states in rodents is with tests that require attention and visual perception for correct performance. Methods: We examined the effects of two drugs that cause disruptions in perception and cognition in humans—the kappa-opioid receptor (KOR) agonist salvinorin A (salvA; 0.125–4.0 mg/kg) and the non-competitive NMDA receptor antagonist ketamine (0.63–20 mg ...


Current Factors Affecting Feeder Cattle Pricing In Kansas And Missouri Cattle Markets, K.W. Harborth, L.L. Schulz, Kevin C. Dhuyvetter, Justin W. Waggoner 2010 Kansas State University Libraries

Current Factors Affecting Feeder Cattle Pricing In Kansas And Missouri Cattle Markets, K.W. Harborth, L.L. Schulz, Kevin C. Dhuyvetter, Justin W. Waggoner

Kansas Agricultural Experiment Station Research Reports

Today's tough economic environment for cattle producers makes each decision critically important, and increased knowledge of the link between pricing and genetic, management, and marketing decisions can increase an operation's sustainability and profitability. Cow-calf producers and cattle feeders have long been interested in the impact of various physical and market characteristics on feeder cattle and calf prices. As demonstrated in many previous studies, significant relationships exist between feeder cattle prices and their physical and market characteristics. Weight, lot size, health, condition, fill, muscling, frame size, breed, time of sale, and horn status significantly affect feeder cattle auction prices ...


Bioavailability Of Biosolids- And Consumer Product-Associated Polybrominated Diphenyl Ether (Pbde) Flame Retardants To Terrestrial Invertebrates, Michael O. Gaylor 2010 College of William and Mary - Virginia Institute of Marine Science

Bioavailability Of Biosolids- And Consumer Product-Associated Polybrominated Diphenyl Ether (Pbde) Flame Retardants To Terrestrial Invertebrates, Michael O. Gaylor

Dissertations, Theses, and Masters Projects

The primary objectives of this research were therefore to evaluate polybrominated diphenyl ether (PBDE) bioavailability to ecologically distinct soil invertebrates exposed to Penta-BDE-treated consumer polyurethane foam (PUF) products and biosolid products with incurred PBDEs. In laboratory bioassays, earthworms (Eisenia fetida) bioaccumulated SigmaPBDEs (47+99+100+183) up to 11,000 mug/kg lipid after 28 days from a mixture of artificial soil and anaerobically-digested sludge biosolid (ADB). Earthworms also bioaccumulated SigmaPBDEs (47+99+100+153+154+183) up to 13,500 and 838,000 mug/kg lipid after 28 d from a mixture of artificial soil and composted sludge biosolid ...


Persistent Organic Pollutants(Pops) As Tracers Of Environmental Change And Antarctic Seabird Ecology, Heidi N. C. Geisz 2010 College of William and Mary - Virginia Institute of Marine Science

Persistent Organic Pollutants(Pops) As Tracers Of Environmental Change And Antarctic Seabird Ecology, Heidi N. C. Geisz

Dissertations, Theses, and Masters Projects

Antarctic seabirds including Adelie penguins (Pygoscelis adeliae), south polar skuas (Catharacta maccormicki), southern giant petrels (Macronectes gigantus) are high trophic level predators that accumulate persistent organic pollutants (POPs) present in the food webs in which they forage. Little is known about the levels of POPs in some Antarctic organisms (e.g. southern giant petrels), as well as the long-term trends of POPs in the Antarctic ecosystem. Samples from all three seabird species were collected post mortem, including eggs, from the Western Antarctic Peninsula (WAP) and in the Ross Sea throughout the austral summer breeding seasons of 2004--2006. The samples were ...


Capacity Of The Bovine Intestinal Mucus And Its Components To Support Escherichia Coli O157:H7 Growth, C. Aperce, J. Heidenreich, James S. Drouillard 2010 Kansas State University Libraries

Capacity Of The Bovine Intestinal Mucus And Its Components To Support Escherichia Coli O157:H7 Growth, C. Aperce, J. Heidenreich, James S. Drouillard

Kansas Agricultural Experiment Station Research Reports

Escherichia coli O157:H7 contamination of human food products is a major concern for the beef industry. The pathogens responsible for outbreaks often originate from cattle, and E. coli O157:H7 can thrive in healthy cattle. To control contamination in the food chain, it is essential to understand how this pathogen is able to grow and compete with other bacteria in the gastrointestinal tracts of cattle. Previous studies have shown that bovine intestinal mucus supports bacterial colonization and can selectively influence makeup of the bacterial population. Intestinal mucus is made of mucins, which are gel-forming glycoproteins. Mucin molecules contain sialic ...


Effects Of Habitat Quality On Secondary Production In Shallow Estuarine Waters And The Consequences For The Benthic-Pelagic Food Web, David James Gillett 2010 College of William and Mary - Virginia Institute of Marine Science

Effects Of Habitat Quality On Secondary Production In Shallow Estuarine Waters And The Consequences For The Benthic-Pelagic Food Web, David James Gillett

Dissertations, Theses, and Masters Projects

Anthropogenic degradation of coastal and estuarine habitats is an ongoing problem facing scientists, natural resource mangers, and the general public. Decreases in habitat quality produce relatively predictable changes in the structure and composition of macrobenthic communities and it has traditionally been assumed that the ecosystem functions of the community change as well. In Chesapeake Bay, the most pervasive cause for the degradation of benthic habitats is the excessive inputs of nutrients that lead to eutrophication and the accumulation of organic matter in the system. Working within this framework, a study was conducted investigating changes in macrobenthic (i.e., secondary) production ...


Comparison Of Medicinal Feed Additives On Health And Growth Performance Of Beef Calves Grazing Native Grass Pasture, M.P. Epp, B. Greenwood, Dale A. Blasi 2010 Kansas State University Libraries

Comparison Of Medicinal Feed Additives On Health And Growth Performance Of Beef Calves Grazing Native Grass Pasture, M.P. Epp, B. Greenwood, Dale A. Blasi

Kansas Agricultural Experiment Station Research Reports

Optimizing growth rate is an important contributor to overall profitability for stocker cattle grazing native Flint Hills pasture. Disease challenges from pinkeye and foot rot have traditionally been problems that compromise health and productivity of stocker cattle in this grazing region. Use of medicinal feed additives as a part of a supplementation program may prevent health problems and improve overall productivity during a spring/summer grazing season.


Capacity Of The Bovine Intestinal Mucus And Its Components To Support Escherichia Coli O157:H7 Growth, C. Aperce, J. Heidenreich, James S. Drouillard 2010 Kansas State University Libraries

Capacity Of The Bovine Intestinal Mucus And Its Components To Support Escherichia Coli O157:H7 Growth, C. Aperce, J. Heidenreich, James S. Drouillard

Kansas Agricultural Experiment Station Research Reports

Escherichia coli O157:H7 contamination of human food products is a major concern for the beef industry. The pathogens responsible for outbreaks often originate from cattle, and E. coli O157:H7 can thrive in healthy cattle. To control contamination in the food chain, it is essential to understand how this pathogen is able to grow and compete with other bacteria in the gastrointestinal tracts of cattle. Previous studies have shown that bovine intestinal mucus supports bacterial colonization and can selectively influence makeup of the bacterial population. Intestinal mucus is made of mucins, which are gel-forming glycoproteins. Mucin molecules contain sialic ...


Supplementing Fructose-Based Block Supplements To Forage-Fed Cattle Increases Capacity For Lactic Acid Metabolism, K.A. Miller, M.J. Quinn, James S. Drouillard 2010 Kansas State University Libraries

Supplementing Fructose-Based Block Supplements To Forage-Fed Cattle Increases Capacity For Lactic Acid Metabolism, K.A. Miller, M.J. Quinn, James S. Drouillard

Kansas Agricultural Experiment Station Research Reports

Acidosis is one of the more important maladies afflicting cattle fed significant amounts of grain and has enormous economic impact for feedlots, dairies, and producers of seed stock. The highest incidence of acidosis occurs when animals are being transitioned from high-roughage diets to diets containing high levels of concentrates. When grain-based diets are consumed in excess, consumed too quickly, or fed without proper adaptation, digestive end products (organic acids) can accumulate within the rumen, resulting in acidosis. Lactic acid is one of the key organic compounds that accumulates under these conditions. Coupled with the animal's limited ability to metabolize ...


Effects Of Crude Glycerin On Ruminal Metabolism And Diet Digestibility Of Flaked-Corn Finishing Diets, G.L. Parsons, James S. Drouillard 2010 Kansas State University Libraries

Effects Of Crude Glycerin On Ruminal Metabolism And Diet Digestibility Of Flaked-Corn Finishing Diets, G.L. Parsons, James S. Drouillard

Kansas Agricultural Experiment Station Research Reports

Expansion of the biodiesel industry has increased supplies of crude glycerin available for livestock feeding. Catalyzed reactions between methanol and triglycerides from vegetable oils, such as soybean oil, yield biodiesel and a coproduct, crude glycerin. Approximately 10% of the weight of soybean oil used to produce biodiesel becomes glycerin. Limited work has been conducted to understand metabolism of glycerin in ruminant livestock. In previous studies at Kansas State University, feeding crude glycerin at 8% or less of the diet improved cattle performance. Subsequent laboratory experiments indicated that low levels of glycerin may improve ruminal fermentation. This study was conducted to ...


High Sulfur Content In Distillers Grains Alters Ruminal Fermentation And Diet Digestibility In Beef Steers, S. Uwituze, G.L. Parsons, K.K. Karges, M.L. Gibson, Larry C. Hollis, James S. Drouillard 2010 Kansas State University Libraries

High Sulfur Content In Distillers Grains Alters Ruminal Fermentation And Diet Digestibility In Beef Steers, S. Uwituze, G.L. Parsons, K.K. Karges, M.L. Gibson, Larry C. Hollis, James S. Drouillard

Kansas Agricultural Experiment Station Research Reports

Requirements for elemental sulfur in feedlot diets have been established to be approximately 0.15% with a maximum upper threshold of 0.40% of diet dry matter. Feeding ethanol fermentation by-products, such as distillers grains with solubles, that are high in sulfur can result in dietary sulfur levels that exceed the recommended maximum. Previous studies indicated that dietary sulfur influenced the site and extent of fiber and protein digestion. The objective of this study was to evaluate ruminal fermentation characteristics and diet digestibility when 30% (dry matter basis) dried distillers grains with solubles with various levels of sulfur was incorporated ...


Effects Of Smartlic Hi-Pro 40 Block Supplements On Ruminal Microbes In Cattle Fed Low-Quality Forages, K.D. Derstein, James S. Drouillard 2010 Kansas State University Libraries

Effects Of Smartlic Hi-Pro 40 Block Supplements On Ruminal Microbes In Cattle Fed Low-Quality Forages, K.D. Derstein, James S. Drouillard

Kansas Agricultural Experiment Station Research Reports

Dormant pastures and native grass hays often are deficient in protein and other nutrients needed to support optimum performance of beef cattle. These nutrients are essential for maintaining viable populations of symbiotic rumen microorganisms that digest the fiber in forages. When nutrient deficiencies occur, microbial populations in the rumen decrease, thereby limiting digestion of low-quality forages. This study was conducted to evaluate changes in rumen microbial populations and digestive activity when cattle consuming low-protein native grass hay are given access to high-protein, free-choice block supplements.


Initial Heifer Body Composition Has Little Impact On Response To Zilmax, L.K. Thompson, C. Schneider, G. Parsons, K. Miller, Christopher D. Reinhardt, James S. Drouillard 2010 Kansas State University Libraries

Initial Heifer Body Composition Has Little Impact On Response To Zilmax, L.K. Thompson, C. Schneider, G. Parsons, K. Miller, Christopher D. Reinhardt, James S. Drouillard

Kansas Agricultural Experiment Station Research Reports

Using a growth promotant at the correct time of finishing is critical for maximizing profit potential. Previous studies have shown that zilpaterol-HCl (Zilmax; Intervet/ Schering-Plough Animal Health, Millsboro, DE) improves carcass characteristics. The objective of this study was to determine effects of prior body composition on subsequent changes in carcass weight, fatness, and muscle in heifers fed Zilmax so producers can introduce Zilmax at the level of finish that will result in the most desirable response. We hypothesized that fatter heifers use fat as the fuel for muscle growth.


Effects Of Extended Zilpaterol-Hcl Withdrawal On Performance And Carcass Traits Of Finishing Beef Heifers, G.L. Parsons, Brandon E. Depenbusch, Christopher D. Reinhardt, D.A. Yates, J.P. Hutcheson, James S. Drouillard 2010 Kansas State University Libraries

Effects Of Extended Zilpaterol-Hcl Withdrawal On Performance And Carcass Traits Of Finishing Beef Heifers, G.L. Parsons, Brandon E. Depenbusch, Christopher D. Reinhardt, D.A. Yates, J.P. Hutcheson, James S. Drouillard

Kansas Agricultural Experiment Station Research Reports

Zilpaterol-HCl (Zilmax; Intervet/Schering-Plough Animal Health, Millsboro; DE) is an orally active β2-adrenergic agonist that is approved for use in feedlot cattle at the rate of 7.56 g/ton of diet dry matter for the final 20 to 40 days on feed. The minimum withdrawal time for Zilmax is 3 days. Zilmax increases hot carcass weight and dressing percentage, primarily as a result of increasing lean muscle mass and decreasing body fat. Zilmax also decreases marbling and increases shear-force values (i.e., less tender) of steaks. This study was conducted to determine whether the benefits of Zilmax would be ...


Supplementing Feedlot Steers And Heifers With Zilmax Increases Proportions Of Strip Loin, Chuck Clod, And Top Sirloin Steaks Exceeding Warner-Bratzler Shear Force Thresholds, Whereas Aging Moderates This Effect, H.C. Claus, J.C. Brooks, J. Shook, G.G. Hilton, T.E. Lawrence, J.M. Mehaffey, B.J. Johnson, Dell M. Allen, M.N. Streeter, W.T. Nichols, C. Melvin, J. Killefer, Michael E. Dikeman 2010 Kansas State University Libraries

Supplementing Feedlot Steers And Heifers With Zilmax Increases Proportions Of Strip Loin, Chuck Clod, And Top Sirloin Steaks Exceeding Warner-Bratzler Shear Force Thresholds, Whereas Aging Moderates This Effect, H.C. Claus, J.C. Brooks, J. Shook, G.G. Hilton, T.E. Lawrence, J.M. Mehaffey, B.J. Johnson, Dell M. Allen, M.N. Streeter, W.T. Nichols, C. Melvin, J. Killefer, Michael E. Dikeman

Kansas Agricultural Experiment Station Research Reports

Ractopamine hydrochloride (Elanco, Greenfield, IN) and Zilmax (zilpaterol hydrochloride; Intervet/Schering-Plough, Millsboro, DE) are β-adrenergic agonists approved in the United States and several other countries to increase growth rate, improve efficiency of feed utilization, and increase carcass meat yield. Zilmax has been shown to improve feed efficiency by 26% and increase hot carcass weight, longissimus muscle area, and meat yield. However, a few studies have shown that Zilmax significantly increased Warner-Bratzler shear force values (decreased tenderness). The objectives of our research were to determine the effects of supplementing feedlot diets of steers and heifers with Zilmax for 0, 20, 30 ...


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