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Genetic And Phenotypic Relationships Between Feed Intake During Lactation And Reproductive Performance, Chad Lewis Yoder Jan 2013

Genetic And Phenotypic Relationships Between Feed Intake During Lactation And Reproductive Performance, Chad Lewis Yoder

Graduate Theses and Dissertations

Daily feed intake during lactation was recorded on purebred Yorkshire (n = 1587), Landrace (n = 2197), and F1 Yorkshire x Landrace (n = 6932) litters from day 1 to 22 of lactation. Lactation feed intake (LFI) curves were predicted using a mixed model which included fixed effects of breed, season, parity group (PG), day of lactation, interactions of day with breed and PG, and a covariate for litter size after cross–fostering. Random effects included litter, contemporary group (herd–year–month), dam, and sire nested within breed. Least squares means for each day were used to define LFI curves by breed through ...


Stocking System Effects On Cattle Performance, Forage, And Soil Properties Of Cool-Season Pastures, Margaret Warter Dunn Jan 2013

Stocking System Effects On Cattle Performance, Forage, And Soil Properties Of Cool-Season Pastures, Margaret Warter Dunn

Graduate Theses and Dissertations

Increasing stocking density and rotation frequency of grazing cattle may improve forage yield and quality and soil carbon content, but may reduce livestock performance and forage persistence and compact soil. Sixty mature August-calving Angus cows (Bos taurus L.; mean body weight (BW), 585 ± 9.9 kg) were allotted to six 4.05-ha cool-season pastures to graze by rotational (RS), strip (SS), or mob (MS) stocking from May through September for two years (2010-2011). Stocking density averaged 16 000, 80 000, and 350 000 kg BW * ha-1 * d-1 in RS, SS, and MS pastures, respectively. Daily live forage allowance was equal ...


The Genetic Basis Of Host Response To Experimental Infection With The Porcine Reproductive And Respiratory Syndrome Virus In Pigs, Nicholas James Boddicker Jan 2013

The Genetic Basis Of Host Response To Experimental Infection With The Porcine Reproductive And Respiratory Syndrome Virus In Pigs, Nicholas James Boddicker

Graduate Theses and Dissertations

Porcine reproductive and respiratory syndrome (PRRS) is the most economically important disease in the swine industry. The effects of PRRS are two fold in that it causes reproductive problems in breeding females and respiratory problems in growing animals. Vaccination has generally not been effective in the prevention of PRRS, partially due to the rapid mutation rate and evolution of the virus. The overall objective of this thesis was to discover the genetic basis of host response to PRRS virus (PRRSV) using data from the PRRS Host Genetics Consortium PRRS-CAP project by conducting genome-wide association analyses and estimating genetic parameters. Eight ...


The Effect Of High And Low Dietary Fiber Diets On The Performance Of Two Lines Of Chickens With Divergent Growth Rates, Muhammed Walugembe Jan 2013

The Effect Of High And Low Dietary Fiber Diets On The Performance Of Two Lines Of Chickens With Divergent Growth Rates, Muhammed Walugembe

Graduate Theses and Dissertations

An experiment was designed to determine the effects of feeding high dietary fiber on the performance, cecal short chain fatty acid (SCFA) concentration and cecal microbial ecology of broiler and layer chicks. All diets were formulated to meet or exceed NRC (1994) standards for starter chicks with the lower fiber diet based on corn-soybean meal (SBM) and the higher fiber diet formulated using corn-SBM-dried distillers grains with solubles (DDGS) and wheat bran. The higher fiber diet contained 60.0 g/kg of both DDGS and wheat bran from 1-12 d and 80.0 g/kg of both DDGS and wheat ...


Mitigation Strategies To Ameliorate Acute And Chronic Heat Stress Utilizing Supplemental Methionine Or Embryonic Thermal Conditioning In Chickens, Kevin Bolek Jan 2013

Mitigation Strategies To Ameliorate Acute And Chronic Heat Stress Utilizing Supplemental Methionine Or Embryonic Thermal Conditioning In Chickens, Kevin Bolek

Graduate Theses and Dissertations

Experiments were conducted exploring potential strategies to mitigate the negative effects of heat stress in chickens. In the first experiment, broilers were placed in environments which were heat treated (HT), thermoneutral (TN), or thermo-neutral coupled with pair-feeding (TN-PF). Birds were fed diets containing either DL-methionine (DLM) or 2-hydroxy-4-methylthiobutanoic acid (HMTBA) formulated to adequate or super-adequate levels of digestible sulfur amino acids (DSAA). Reduced (GSH), oxidized (GSSG), and total (TGSH) glutathione as well glutathione peroxidase (GPx) activity were measured to assess antioxidant capacity. Thiobarbituric acid reactive substances (TBARS) were measured to assess lipid peroxidation. Several blood variables were also measured. Responses ...


Characterizing The Porcine Immune Response To An Environmental And Pathogenic Challenge: Swine Barn Dust And Salmonella Infection, Susan Knetter Jan 2013

Characterizing The Porcine Immune Response To An Environmental And Pathogenic Challenge: Swine Barn Dust And Salmonella Infection, Susan Knetter

Graduate Theses and Dissertations

Pork is the most highly consumed meat worldwide, and the swine industry generates $34.5 billion annually to the U.S. economy alone. Maintaining pork safety and minimizing production losses associated with swine disease impacts profitability, food safety and animal health. As such, the research presented herein focused on characterizing aspects of the porcine immune response to two challenges that impact swine health: swine barn dust exposure and Salmonella infection.

In the first set of experiments, swine barn organic dust extract (ODE) treatment negatively affected porcine macrophage phagocytosis, intracellular bacterial killing and NF-kB translocation. Further, ODE stimulated production of inflammatory ...


Evaluation Of A Pilot Land-Based Marine Integrated Aquaculture System, Suzanne Boxman Jan 2013

Evaluation Of A Pilot Land-Based Marine Integrated Aquaculture System, Suzanne Boxman

Graduate Theses and Dissertations

Recirculating aquaculture systems (RAS) produce aquaculture products on land with minimal discharge of waste products and minimal water loss. High costs associated with waste treatment for RAS have triggered the growth of integrated aquaculture systems (IAS) which incorporate macrophytes (aquatic plants) into the treatment train. The objective of this research was to examine a pilot scale inland marine IAS with three different methods for solids treatment: a sand filter followed by a plant bed, only a plant bed, and geotextile bags. Florida Pompano (Trachinotus carolinus) were grown along with Smooth Cordgrass (Spartina alterniflora), Black Needle Rush (Juncus romerianus), and Red ...


Investigation Of Condition Effects On Batch Fecundity Of The Common Snook, Centropomus Undecimalis, In Tampa Bay, Florida, Catherine Michelle Bruger Hayslip Jan 2013

Investigation Of Condition Effects On Batch Fecundity Of The Common Snook, Centropomus Undecimalis, In Tampa Bay, Florida, Catherine Michelle Bruger Hayslip

Graduate Theses and Dissertations

Common snook, Centropomus undecimalis, is a popular game fish species that occurs throughout central and southern Florida, yet many questions remain unanswered regarding their reproductive strategies, including estimates of fecundity with relation to size, age, and condition of the female. These relationships are critical to improving stock assessments and fundamental to estimating spawning potential ratio, the measure by which snook are managed. Spawning snook were collected from a known spawning site, Rattlesnake Key, Tampa Bay, Florida, during three consecutive spawning seasons (2009-2011) and batch fecundity for snook was reported for the first time. Of the 43 females suitable for fecundity ...


Relative Survival Of Gags Mycteroperca Microlepis Released Within A Recreational Hook-And-Line Fishery: Application Of The Cox Regression Model To Control For Heterogeneity In A Large-Scale Mark-Recapture Study, Beverly J. Sauls Jan 2013

Relative Survival Of Gags Mycteroperca Microlepis Released Within A Recreational Hook-And-Line Fishery: Application Of The Cox Regression Model To Control For Heterogeneity In A Large-Scale Mark-Recapture Study, Beverly J. Sauls

Graduate Theses and Dissertations

The objectives of this study were to measure injuries and impairments directly observed from gags Mycteroperca microlepis caught and released within a large-scale recreational fishery, develop methods that may be used to rapidly assess the condition of reef fish discards, and estimate the total portion of discards in the fishery that suffer latent mortality. Fishery observers were placed on for-hire charter and headboat vessels operating in the Gulf of Mexico from June 2009 through December 2012 to directly observe reef fishes as they were caught by recreational anglers fishing with hook-and-line gear. Fish that were not retained by anglers were ...


Investigating The Control Of Listeria Monocytogenes On Uncured, No-Nitrate-Or-Nitrite-Added Ready-To-Eat Meat Products Using Natural Antimicrobial Ingredients And Post-Lethality Interventions, Nicolas Armando Lavieri Jan 2013

Investigating The Control Of Listeria Monocytogenes On Uncured, No-Nitrate-Or-Nitrite-Added Ready-To-Eat Meat Products Using Natural Antimicrobial Ingredients And Post-Lethality Interventions, Nicolas Armando Lavieri

Graduate Theses and Dissertations

Restrictions on the use of conventional antimicrobials, combined with the restricted use of nitrite and nitrate, have generated concerns over the perceived risk for foodborne illness associated with natural and organic RTE meat and poultry products. Thus, the use of natural antimicrobial interventions alone and in combination with post-lethality interventions as a means to inhibit the recovery and growth of Listeria monocytogenes in naturally cured RTE processed meats was the focus of the work reported in this dissertation. Natural antimicrobials evaluated were cranberry powder, vinegar, and vinegar and lemon juice concentrate. Post-lethality interventions studied were high hydrostatic pressure, lauric arginate ...


Effects Of Flow Rate, Gas Type And Disease Status On The Welfare Of Sucking And Weaned Pigs During Gas Euthanasia, Larry Joseph Sadler Jan 2013

Effects Of Flow Rate, Gas Type And Disease Status On The Welfare Of Sucking And Weaned Pigs During Gas Euthanasia, Larry Joseph Sadler

Graduate Theses and Dissertations

Gas euthanasia of swine on farms is increasingly common. However, there is controversy regarding pig welfare during gas euthanasia and research must be conducted to establish best practices ensuring minimal pain and distress. The objectives of these studies were to determine pig welfare and efficacy of processes with various gas euthanasia procedures: gas type (carbon dioxide, argon, carbon dioxide:argon mixture), flow rate (20%, 35%, 50%, prefill), age (neonate, weaned) and disease status of the pig (respiratory disease/depression vs. other reasons). Euthanasia with inhalant gases can produce confounding effects on physiologic responses, therefore behavior was chosen as the primary ...


The Effect Of Ph And Nitrite Concentration On The Antimicrobial Impact Of Celery Juice Compared With Sodium Nitrite On Listeria Monocytogenes, Ashley Horsch Jan 2013

The Effect Of Ph And Nitrite Concentration On The Antimicrobial Impact Of Celery Juice Compared With Sodium Nitrite On Listeria Monocytogenes, Ashley Horsch

Graduate Theses and Dissertations

Increasing consumer concerns of harmful preservatives have intensified consumers' demand for natural and organic alternatives. In response to this demand, uncured or no-nitrate-or-nitrite-added meat products which utilize celery juice concentrates as an alternative to sodium nitrite, have emerged on the market to replace conventional nitrite sources. The objective of this study was to evaluate the effect of celery juice pH for the impact of nitrite on L. monocytogenes growth. In addition, equal concentrations of nitrite in celery juice and conventional nitrite were evaluated to determine the impact of nitrite concentration from these sources on L. monocytogenes growth. These objectives were ...


Biophysical Interactions In Prairie Pothole Wetlands Of Iowa: Consequences For Macroinvertebrate Assemblages And Ecosystem Condition, Kristine Maurer Jan 2013

Biophysical Interactions In Prairie Pothole Wetlands Of Iowa: Consequences For Macroinvertebrate Assemblages And Ecosystem Condition, Kristine Maurer

Graduate Theses and Dissertations

Wetlands are capable of supporting diverse assemblages of plants and animals, and performing various ecosystem services (e.g., waterfowl production, flood mitigation). However, the capacity of a wetland to perform these functions is dependent upon its condition (i.e., ecosystem condition, integrity, or health). Wetland condition is affected and reflected by internal (within-system) biophysical features, and interactions among these features. To protect and effectively manage wetlands, it is essential that we identify reliable determinants and indicators of wetland condition. As a result of the inherent complexity of wetland ecosystem interactions, this knowledge is difficult to obtain. The objectives of this ...


Reproductive Decisions Of Mountain Plovers In Southern Phillips County, Montana, Paul Daniel Blom Skrade Jan 2013

Reproductive Decisions Of Mountain Plovers In Southern Phillips County, Montana, Paul Daniel Blom Skrade

Graduate Theses and Dissertations

The Mountain Plover (Charadrius montanus) is a shorebird of conservation concern that breeds in the Great Plains and the Great Basin. They have an uncommon uniparental care system where males and females tend separate nests. Although males and females have similar incubation and chick-rearing responsibilities, it is thought that the males arrive first to the breeding grounds in early to mid-April, establish loose territories, and compete for females. Long-term monitoring of this species in north-central Montana has allowed for studies comparing the effectiveness of the two sexes at separately raising young, showing evidence for differences in nest and brood survival ...


Hybrid Striped Bass: Culture And Use In Midwestern Waters, James Wamboldt Jan 2013

Hybrid Striped Bass: Culture And Use In Midwestern Waters, James Wamboldt

Graduate Theses and Dissertations

In response to increased demand from fisheries managers, the Iowa Department of Natural Resources and Iowa State University worked to produce standard operating procedures for pond culture of hybrid striped bass Morone saxatilis × M. chrysops in Iowa. In 2011 we evaluated an organic fertilization regime in nutrient rich earthen ponds. In addition to pond fertilization, the role of offering a supplemental commercial feed during phase I culture was also investigated within plastic-lined ponds. With greater utilization and stocking of hybrid striped bass fingerlings in local waters, we also sought to evaluate the effects that introductions have on the trophic dynamics ...


Characterization Of The Effects Of Intestinal Physiology Modified By Exogenous Enzymes And Direct-Fed Microbial On Intestinal Integrity, Energy Metabolism, Body Composition And Performance Of Laying Hens And Broiler Chickens, Ganapathi Raj Murugesan Jan 2013

Characterization Of The Effects Of Intestinal Physiology Modified By Exogenous Enzymes And Direct-Fed Microbial On Intestinal Integrity, Energy Metabolism, Body Composition And Performance Of Laying Hens And Broiler Chickens, Ganapathi Raj Murugesan

Graduate Theses and Dissertations

The objective of this dissertation was to evaluate the effects of exogenous enzymes (EE) and direct-fed microbial (DFM) supplementation on bird intestinal integrity, energy metabolism, body composition and performance of laying hens and broiler chickens. The effects of reduced dietary metabolizable energy (ME) on performance, intestinal integrity and body composition of laying hens were evaluated in two experiments. A reduction of 90 kcal/kg of dietary ME over a period of 12 weeks did not significantly alter performance or nitrogen corrected apparent ME (AMEn), but reduced abdominal fat pad. In the follow-up experiment, no significant differences were noted in performance ...


Novel Mechanisms Involved With Lipid Metabolism In Adipose Tissue Of Dairy Cows, Dawn Koltes Jan 2013

Novel Mechanisms Involved With Lipid Metabolism In Adipose Tissue Of Dairy Cows, Dawn Koltes

Graduate Theses and Dissertations

Proper lipid metabolism is essential to the maintenance of milk production and fitness in the modern dairy cow. Little is known about the regulation of lipid metabolism in adipose tissue in dairy cattle, including the roles of adipokines and lipid droplet associated proteins. Therefore, the objectives of this study were to characterized changes in transcript abundances of adipokines during three different energy altering models, and lipid droplet associated proteins throughout the transition period and with leptin induced lipolysis. Transcript abundances of leptin decreased during feed restriction, while angiopoietin like protein 4 (ANGPTL4) increased during early lactation, feed restriction, and following ...


Performance, Carcass Traits And Fatty Acid Profiles Of Yearling Beef Cattle Supplemented With Self-Fed Byproducts On Pasture, Daniel Dean Kiesling Jan 2013

Performance, Carcass Traits And Fatty Acid Profiles Of Yearling Beef Cattle Supplemented With Self-Fed Byproducts On Pasture, Daniel Dean Kiesling

Graduate Theses and Dissertations

Due to rising costs of conventional feedstuffs, more research has been focused on feeding non-conventional feedstuffs, such as byproducts of ethanol production or further processing of grains (i.e. soyhulls). Because of the health benefits of conjugated linoleic acid (CLA) shown in studies on laboratory animals, consumer interest in foods enriched with CLA has increased. The objective of this study was to investigate the effects of finishing yearling market steers on pasture supplemented with combinations of self-fed byproducts on live animal performance, carcass traits and fatty acid profiles; specifically CLA. British and Continental crossbred beef steers (n = 162, BW = 404 ...


The Effect Of Sulfur In Cattle Diets With Varying Cation-Anion Balances Upon Feedlot Performance, Blood Chemistry And Body Fluid Compartments., Paul Gene Summer Jan 2013

The Effect Of Sulfur In Cattle Diets With Varying Cation-Anion Balances Upon Feedlot Performance, Blood Chemistry And Body Fluid Compartments., Paul Gene Summer

Graduate Theses and Dissertations

Feeding higher levels of corn distillers grains with solubles (DGS) increases sulfur intake by animals. Excess sulfur in beef finishing diets has been associated with reduced dry matter intake (DMI), body weight (BW) gain, and a negative dietary cation-anion difference (DCAD). The objectives of this work were to determine if adding cations to cattle finishing diets high in sulfur could improve performance and to measure physiological responses in cattle to high sulfur intake with a negative or positive DCAD.

The potential of supplemental cations to increase DCAD and improve performance of cattle consuming finishing diets containing modified distillers with solubles ...


Molecular Technologies In The Science And Policy Of Florida Largemouth Bass Micropterus Floridanus Management In Florida, Josh Sakmar Jan 2013

Molecular Technologies In The Science And Policy Of Florida Largemouth Bass Micropterus Floridanus Management In Florida, Josh Sakmar

Graduate Theses and Dissertations

Advances in molecular technologies have provided conservation biologist with the opportunity to quantify the genetic structure of a population and, in turn develop management guidelines and policies aimed at preserving the genetic diversity of fish stocks challenged by human activities. This thesis examines the status of genetics as applied to the management of freshwater fisheries by state natural resource agencies with a purpose of understanding the keys to a successful genetics program. An online survey was used to investigate the breadth of molecular marker application to freshwater fisheries management by state natural resource departments. Seven questions were posed to 50 ...


Fish Assemblages In Iowa's Nonwadeable Rivers: Historic Changes In Assemblage Structure And Relationships With Natural And Anthropogenic Environmental Characteristics, Timothy Parks Jan 2013

Fish Assemblages In Iowa's Nonwadeable Rivers: Historic Changes In Assemblage Structure And Relationships With Natural And Anthropogenic Environmental Characteristics, Timothy Parks

Graduate Theses and Dissertations

Nonwadeable or large rivers are dynamic aquatic ecosystems capable supporting high fish biodiversity. Due to human activities on the landscape and in waterways, large rivers and their associated fish assemblages have become increasingly imperiled. It is essential to understand fish response to human activities in order to provide effective management and conservation measures. In response to these concerns, our objectives were to 1) evaluate the historic changes in fish assemblages that occurred in Iowa's interior nonwadeable rivers via representative changes occurring in five focal river systems and 2) determine the relationship between fish assemblage structure and environmental characteristics measured ...


Characterization Of The Skeletal Muscle Calpain/Calpastatin System In Growth Models In Swine And Cattle, Shannon Michelle Cruzen Jan 2013

Characterization Of The Skeletal Muscle Calpain/Calpastatin System In Growth Models In Swine And Cattle, Shannon Michelle Cruzen

Graduate Theses and Dissertations

The overall objective of the work in this dissertation was to characterize -calpain, m-calpain, and calpastatin activities in order to learn more about the system in the live animal as well as its potential effects on postmortem proteolysis. Animal models of efficiency and growth were used to achieve this objective.

The first specific objective was to evaluate muscle protein turnover differences in pigs selected for residual feed intake (RFI). Muscle samples were collected, and insulin signaling, protein synthesis, and specific protein degradation proteins were analyzed for expression and activities in twelve gilts each from low (LRFI) and high (HRFI) RFI ...


The Use Of Selection To Improve Sow Longevity, Caitlyn Elizabeth Abell Jan 2013

The Use Of Selection To Improve Sow Longevity, Caitlyn Elizabeth Abell

Graduate Theses and Dissertations

The objective of this dissertation was to evaluate multiple approaches to incorporating sow longevity or lifetime sow productivity into a selection program. Sow longevity can be selected for using indicator traits, such as structural soundness and lameness. In the first study, objective measurements to detect sow lameness were examined. Lameness was chemically induced for a short time period in multiparous sows and their weight distribution and walking gait were objectively measured in the days following lameness induction. Using a classification tree analysis, it was determined that the mean weight being placed on each leg was the most predictive measurement when ...