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Analysis Of Population Structure In A California Newt (Taricha Torosa) Metapopulation, Jessica Vincent 2017 Western Kentucky University

Analysis Of Population Structure In A California Newt (Taricha Torosa) Metapopulation, Jessica Vincent

Honors College Capstone Experience/Thesis Projects

As anthropogenic influences take an ever-increasing toll on the environment, understanding how environmental change affects species is paramount. Concern regarding decline in amphibian populations has spurred research examining the effects of habitat change on the dynamics of populations at landscape levels. One important goal is to understand how gene flow among populations is affected by changes in habitat. Biologists need to consider the relationship between gene flow and habitat alterations so that movements among individual breeding ponds can be maintained over time, reducing risk of local extinction events. This study focuses on patterns of gene flow among thirteen populations of ...


Unique Genetic Differences In Responses Of Chicken Immune Cells To An Inflammatory Stimulus And Heat Stress, Angelica Van Goor, Anna Slawinska, Carl Schmidt, Susan J. Lamont 2017 Iowa State University

Unique Genetic Differences In Responses Of Chicken Immune Cells To An Inflammatory Stimulus And Heat Stress, Angelica Van Goor, Anna Slawinska, Carl Schmidt, Susan J. Lamont

Susan J. Lamont

Bone marrow antigen presenting cells (BM-APC), from Fayoumis (disease resistant and heat tolerant) and Leghorn (disease susceptible) chicken lines were evaluated for response to an inflammatory stimulus and heat stress. BM-APC from Fayoumis produced more nitric oxide (NO) and had higher Major Histocompatibility Complex (MHC) class II cell surface expression compared to those from Leghorn, indicating that BM-APC studied in vitro may be a useful tool to evaluate molecular effects of disease and/or heat tolerance in chickens.


Infection Of Commercial Laying Hens With Newcastle Disease Virus: Differing Responses Between Birds Provide Potential For Genetic Improvement Through Selection, Kaylee Rowland, Huaijun Zhou, Rodrigo Gallardo, David Bunn, Susan J. Lamont 2017 Iowa State University

Infection Of Commercial Laying Hens With Newcastle Disease Virus: Differing Responses Between Birds Provide Potential For Genetic Improvement Through Selection, Kaylee Rowland, Huaijun Zhou, Rodrigo Gallardo, David Bunn, Susan J. Lamont

Susan J. Lamont

Exotic Newcastle Disease Virus (ENDV) cause extremely rapid mortality in chickens after exposure to the virus. People rely heavily on poultry to provide protein and income in many places where NDV is not effectively controlled through vaccination and biosecurity. Losses from NDV contribute to worldwide hunger and poverty. It may be possible to use genetic selection to produce chickens that have a stronger immune response in the face of NDV challenge. For genetic selection to be successful, two major elements are required: differences in immune response among chickens and genetic control of these differences. This study clearly demonstrated the existence ...


Effects Of Diet And Genetics On Production Traits In Response To Repeated Exposure To Heat Stress In Pigs, Wendy Rauw, Johana Mayorga Lozano, Soi Lei, John Patience, Nicholas Gabler, Steven Lonergan, Jack Dekkers, Lance Baumgard 2017 Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria

Effects Of Diet And Genetics On Production Traits In Response To Repeated Exposure To Heat Stress In Pigs, Wendy Rauw, Johana Mayorga Lozano, Soi Lei, John Patience, Nicholas Gabler, Steven Lonergan, Jack Dekkers, Lance Baumgard

Steven M. Lonergan

Hot temperatures negatively impact global livestock production and are a serious financial burden to pig producers. Trends predict that global temperatures will continue toincrease, making this a pertinent issue now and in the future. Study objectives were to investigate the effects of genetics and dietary fiber content on growth,feed intake, and feed conversion efficiencyin response to repeated exposure to heat stress.Atotal of 103 finishing barrows from a contemporary commercial line and Yorkshire linesdivergently selected for high and low feed efficiency based on residual feed intake (RFI) were used in this experiment. All pigs were subjected three consecutivetimes to ...


Qtls Associated With Dry Matter Intake, Metabolic Mid-Test Weight, Growth And Feed Efficiency Have Little Overlap Across 4 Beef Cattle Studies, Mahdi Saatchi, Jonathan E. Beever, Jared E. Decker, Dan B. Faulkner, Harvey C. Freetly, Stephanie L. Hansen, Helen Yampara-Iquise, Kristen A. Johnson, Stephen D. Kachman, Monty S. Kerley, JaeWoo Kim, Daniel D. Loy, Elisa Marques, Holly L. Neibergs, E. John Pollak, Robert D. Schnabel, Christopher M. Seabury, Daniel W. Shike, W. M. Snelling, Matthew L. Spangler, Robert L. Weaber, D. J. Garrick, Jeremy F. Taylor 2017 Iowa State University

Qtls Associated With Dry Matter Intake, Metabolic Mid-Test Weight, Growth And Feed Efficiency Have Little Overlap Across 4 Beef Cattle Studies, Mahdi Saatchi, Jonathan E. Beever, Jared E. Decker, Dan B. Faulkner, Harvey C. Freetly, Stephanie L. Hansen, Helen Yampara-Iquise, Kristen A. Johnson, Stephen D. Kachman, Monty S. Kerley, Jaewoo Kim, Daniel D. Loy, Elisa Marques, Holly L. Neibergs, E. John Pollak, Robert D. Schnabel, Christopher M. Seabury, Daniel W. Shike, W. M. Snelling, Matthew L. Spangler, Robert L. Weaber, D. J. Garrick, Jeremy F. Taylor

Stephanie L. Hansen

Background: The identification of genetic markers associated with complex traits that are expensive to record such as feed intake or feed efficiency would allow these traits to be included in selection programs. To identify large-effect QTL, we performed a series of genome-wide association studies and functional analyses using 50 K and 770 K SNP genotypes scored in 5,133 animals from 4 independent beef cattle populations (Cycle VII, Angus, Hereford and Simmental × Angus) with phenotypes for average daily gain, dry matter intake, metabolic mid-test body weight and residual feed intake. Results: A total of 5, 6, 11 and 10 significant ...


Genetic Basis And Functional Consequences Of Differential Expression Of The Cmeabc Efflux Pump In Campylobacter Jejuni Isolates, Tara Grinnage-Pulley, Qijing Zhang 2017 Iowa State University

Genetic Basis And Functional Consequences Of Differential Expression Of The Cmeabc Efflux Pump In Campylobacter Jejuni Isolates, Tara Grinnage-Pulley, Qijing Zhang

Qijing Zhang

The CmeABC multidrug efflux transporter of Campylobacter jejuni plays a key role in antimicrobial resistance and is suppressed by CmeR, a transcriptional regulator of the TetR family. Overexpression of CmeABC has been observed in laboratory-generated mutants, but it is unknown if this phenotype occurs naturally in C. jejuni isolates and if it has any functional consequences. To answer these questions, expression of cmeABC in natural isolates obtained from broiler chickens, turkeys and humans was examined, and the genetic mechanisms and role of cmeABC differential expression in antimicrobial resistance was determined. Among the 64 C. jejuni isolates examined in this study ...


Identification Of A Novel G2073a Mutation In 23s Rrna In Amphenicol-Selected Mutants Of Campylobacter Jejuni, Licai Ma, Zhangqi Shen, Gaowa Naren, Hui Li, Xi Xia, Congming Wu, Jianzhong Shen, Qijing Zhang, Yang Wang 2017 China Agricultural University

Identification Of A Novel G2073a Mutation In 23s Rrna In Amphenicol-Selected Mutants Of Campylobacter Jejuni, Licai Ma, Zhangqi Shen, Gaowa Naren, Hui Li, Xi Xia, Congming Wu, Jianzhong Shen, Qijing Zhang, Yang Wang

Qijing Zhang

Objectives This study was conducted to examine the development and molecular mechanisms of amphenicol resistance in Campylobacter jejuni by using in vitro selection with chloramphenicol and florfenicol. The impact of the resistance development on growth rates was also determined using in vitro culture. Methods Chloramphenicol and florfenicol were used as selection agents to perform in vitro stepwise selection. Mutants resistant to the selective agents were obtained from the selection process. The mutant strains were compared with the parent strain for changes in MICs and growth rates. The 23S rRNA gene and the L4 and L22 ribosomal protein genes in the ...


Morphological Variation In The Wild-Weedy Complex Of Sorghum Bicolor In Situ In Western Kenya: Preliminary Evidence Of Crop-To-Wild Gene Flow?, James A. Okeno, Evans Mutegi, Santie de Villiers, Jeffrey D. Wolt, Manjit K. Misra 2017 Iowa State University

Morphological Variation In The Wild-Weedy Complex Of Sorghum Bicolor In Situ In Western Kenya: Preliminary Evidence Of Crop-To-Wild Gene Flow?, James A. Okeno, Evans Mutegi, Santie De Villiers, Jeffrey D. Wolt, Manjit K. Misra

Manjit K. Misra

Crop wild relatives are important components of agroecosystems and have over the years been exploited in breeding programs as sources of genes for novel traits. Information on the extent and patterns of variability is important in formulating effective conservation and utilization strategies for existing crop wild relative populations. We conducted surveys and collections of wild and weedy accessions of Sorghum bicolor (L.) Moench in Lambwe Valley in western Kenya in order to investigate occurrence, distribution, and morphological variability in the wild-weedy complex of S. bicolor under local agroecological conditions. We also attempted to understand the role, if any, of crop-to-wild ...


Genetic Analysis Of The Federally Endangered Winged Mapleleaf Mussel To Aid Proposed Re-Introduction Efforts, Kevin J. Roe 2017 Iowa State University

Genetic Analysis Of The Federally Endangered Winged Mapleleaf Mussel To Aid Proposed Re-Introduction Efforts, Kevin J. Roe

Kevin J. Roe

The winged mapleleaf, Quadrula fragosa, historically occurred in the Mississippi, Tennessee, Ohio, and Cumberland river drainages, but has suffered severe population and range reductions. At the time that the species was federally listed as endangered, its range was thought to have been reduced to a stretch of the St. Croix River between northwestern Wisconsin and east-central Minnesota. Recently, morphologically “Q. fragosa-like” specimens were discovered at sites in Arkansas (Ouachita River and Saline River), Missouri (Bourbeuse River), and Oklahoma (Little River). Subsequently, a plan was proposed to re-introduce Q. fragosa into portions of its historic range where its been extirpated from ...


A Comparison Of Six Maternal Genetic Lines For Sow Longevity, T. Serenius, Kenneth J. Stalder, Tom J. Baas, John W. Mabry, Rodney N. Goodwin 2017 Iowa State University

A Comparison Of Six Maternal Genetic Lines For Sow Longevity, T. Serenius, Kenneth J. Stalder, Tom J. Baas, John W. Mabry, Rodney N. Goodwin

Kenneth J Stalder

Data from the National Pork Producers Council Maternal Line National Genetic Evaluation Program were used to compare the sow longevity of six different genetic lines, and to estimate the associations of gilt backfat thickness, age at first farrowing, litter size at first farrowing, litter weight at first farrowing, average feed intake during lactation, and average backfat loss during lactation with sow longevity. The lines evaluated were American Diamond Genetics, Danbred North America, Dekalb-Monsanto DK44, Dekalb-Monsanto GPK347, Newsham Hybrids, and National Swine Registry. The results suggest that the sows of Dekalb-Monsanto GPK347 had a clearly lower risk of being culled than ...


Investigation Of The Chemical Interface In The Soybean–Aphid And Rice–Bacteria Interactions Using Maldi-Mass Spectrometry Imaging, Adam T. Klein, Gargey B. Yagnik, Jessica D. Hohenstein, Zhiyuan Ji, Jiachen Zi, Malinda D. Reichert, Gustavo C. Macintosh, Bing Yang, Reuben J. Peters, Javier Vela, Young Jin Lee 2017 Iowa State University

Investigation Of The Chemical Interface In The Soybean–Aphid And Rice–Bacteria Interactions Using Maldi-Mass Spectrometry Imaging, Adam T. Klein, Gargey B. Yagnik, Jessica D. Hohenstein, Zhiyuan Ji, Jiachen Zi, Malinda D. Reichert, Gustavo C. Macintosh, Bing Yang, Reuben J. Peters, Javier Vela, Young Jin Lee

Reuben J. Peters

Mass spectrometry imaging (MSI) is an emerging technology for high-resolution plant biology. It has been utilized to study plant–pest interactions, but limited to the surface interfaces. Here we expand the technology to explore the chemical interactions occurring inside the plant tissues. Two sample preparation methods, imprinting and fracturing, were developed and applied, for the first time, to visualize internal metabolites of leaves in matrix-assisted laser desorption ionization (MALDI)-MSI. This is also the first time nanoparticle-based ionization was implemented to ionize diterpenoid phytochemicals that were difficult to analyze with traditional organic matrices. The interactions between rice–bacterium and soybean ...


The Maize (Zea Mays L.) Roothairless3 Gene Encodes A Putative Gpi-Anchored, Monocot-Specific, Cobra-Like Protein That Significantly Affects Grain Yield, Frank Hochholdinger, Tsui-Jung Wen, Patricia Chimot-Marolle, Oswaldo Da Costa e Silva, Wesley Bruce, Kendall R. Lamkey, Udo Wienand, Patrick S. Schnable 2017 Eberhard Karls Universität Tübingen

The Maize (Zea Mays L.) Roothairless3 Gene Encodes A Putative Gpi-Anchored, Monocot-Specific, Cobra-Like Protein That Significantly Affects Grain Yield, Frank Hochholdinger, Tsui-Jung Wen, Patricia Chimot-Marolle, Oswaldo Da Costa E Silva, Wesley Bruce, Kendall R. Lamkey, Udo Wienand, Patrick S. Schnable

Kendall R Lamkey

The rth3 (roothairless 3) mutant is specifically affected in root hair elongation. We report here the cloning of the rth3 gene via a PCR-based strategy (amplification of insertion mutagenized sites) and demonstrate that it encodes a COBRA-like protein that displays all the structural features of a glycosylphosphatidylinositol anchor. Genes of the COBRA family are involved in various types of cell expansion and cell wall biosynthesis. The rth3 gene belongs to a monocot-specific clade of the COBRA gene family comprising two maize and two rice genes. While the rice (Oryza sativa) gene OsBC1L1 appears to be orthologous to rth3 based on ...


Temporal Changes In Allele Frequencies In Two Reciprocally Selected Maize Populations, J. A. Labate, Kendall R. Lamkey, Michael Lee, W. L. Woodman 2017 United States Department of Agriculture

Temporal Changes In Allele Frequencies In Two Reciprocally Selected Maize Populations, J. A. Labate, Kendall R. Lamkey, Michael Lee, W. L. Woodman

Kendall R Lamkey

The effects of breeding on allele frequency changes at 82 restriction fragment length polymorphism (RFLP) loci were examined in two maize (Zea mays L.) populations undergoing reciprocal recurrent selection, Iowa Stiff Stalk Synthetic and Iowa Corn Borer Synthetic #1. After 12 cycles of selection, approximately 30% of the alleles were extinct and 10% near fixation in each population. A test of selective neutrality identified several loci in each population whose allele frequency changes cannot be explained by genetic drift; interpopulation mean expected heterozygosity increased for that subset of 28 loci but not for the remaining 54 loci. Mean expected heterozygosity ...


Estimates Of Heterosis And Inbreeding Depression For Crosses Of Lowa Maize Populations, T. A. Scheffler, Arnel R. Hallauer, Kendall R. Lamkey, Paul R. White 2017 Iowa State University

Estimates Of Heterosis And Inbreeding Depression For Crosses Of Lowa Maize Populations, T. A. Scheffler, Arnel R. Hallauer, Kendall R. Lamkey, Paul R. White

Kendall R Lamkey

Relative success of maize (Zea mays L.) breeding programs depends on the proper choice of parental germplasm and the recognition and the use of heterotic groups. Our objective was to identify maize populations with exotic germplasm that would be potentially useful germplasm sources in temperate area maize breeding programs. A factorial mating design was used to produce 35 crosses between seven Iowa Stiff Stalk Synthetic and five non-Iowa Stiff Stalk Synthetic populations. The 12 parental populations and their 35 population crosses also were selfed to produce F2 generation. The two sets of genetic materials were evaluated at five Iowa locations ...


Strategies For The Production Of Maize-Derived Pharmaceuticals Using Cytoplasmic Male Sterile Lines: In Vitro Tissue Culture/Transformation And Field Breeding Approaches, Kan Wang, Bronwyn R. Frame, X. Xu, Kendall R. Lamkey 2017 Iowa State University

Strategies For The Production Of Maize-Derived Pharmaceuticals Using Cytoplasmic Male Sterile Lines: In Vitro Tissue Culture/Transformation And Field Breeding Approaches, Kan Wang, Bronwyn R. Frame, X. Xu, Kendall R. Lamkey

Kendall R Lamkey

Plant-made pharmaceuticals (PMPs) offer promise as efficient and cost-effective products for the treatment of human and animal diseases. An advantage of producing pharmaceuticals in maize is the large storage capacity and stability for proteins and starch in seed, allowing for manufacturing recombinant proteins such as antigens and antibodies. Other advantages of the maize system include safety, high yields, and scalability of production and processing. However, the benefits of this technology must be balanced against potential health and environmental risks that may be associated with its use. Because PMPs presently have no provision for regulatory tolerance, their inadvertent occurrence in foods ...


Recurrent Selection To Alter Grain Methionine Concentration And Improve Nutritional Value Of Maize, M. Paul Scott, Audrey Darrigues, Timothy S. Stahly, Kendall R. Lamkey 2017 United States Department of Agriculture

Recurrent Selection To Alter Grain Methionine Concentration And Improve Nutritional Value Of Maize, M. Paul Scott, Audrey Darrigues, Timothy S. Stahly, Kendall R. Lamkey

Kendall R Lamkey

Methionine is an essential amino acid that is limiting in maize- (Zea mays L.) based diets. The objective of this work was to determine whether we could alter grain methionine concentration in random-mated maize populations by mass selection for methionine concentration using a microbial assay. In one study, we developed two populations by selecting for high or low methionine concentration (HM or LM, respectively) for three generations starting from the random-mated population BS11. Grain from these populations was used to formulate diets for a feeding trial in which 15 rats were fed HM grain and 15 rats were fed LM ...


Storage Of Molecular Marker Data In Databases For Efficient Use In Plant Breeding Programs, Matthias Frisch, Kendall R. Lamkey, Albrecht E. Melchinger 2017 Universität Hohenheim

Storage Of Molecular Marker Data In Databases For Efficient Use In Plant Breeding Programs, Matthias Frisch, Kendall R. Lamkey, Albrecht E. Melchinger

Kendall R Lamkey

With the increased use of molecular markers in plant breeding programs, appropriate storage of these data becomes an important issue. The concept for storage of molecular marker data in databases proposed in this paper is simple and generic so that it can be implemented on a personal computer and integrated in large-scale database systems. Application of the proposed data structure simplifies standardized statistical analyses and reanalyses of experimental data as well as data exchange and reuse of programmed analysis routines.


Population Genetic Diversity In A Maize Reciprocal Recurrent Selection Program, Lori L. Hinze, Stephen Kresovich, Jason D. Nason, Kendall R. Lamkey 2017 United States Department of Agriculture

Population Genetic Diversity In A Maize Reciprocal Recurrent Selection Program, Lori L. Hinze, Stephen Kresovich, Jason D. Nason, Kendall R. Lamkey

Kendall R Lamkey

The genetic structures of the Iowa Corn Borer Synthetic #1 (CB) and Iowa Stiff Stalk Synthetic (SS) maize (Zea mays L.) populations are important because these populations serve as the model for development of modern commercial hybrids. In 1949, CB and SS were used to start a reciprocal recurrent selection (RRS) breeding program at Iowa State University. This study was conducted to analyze more thoroughly the genetic diversity within this RRS program and illustrate how the RRS program has changed over time at the molecular level. The progress of this program was measured by analyzing the variation at 86 SSR ...


Population Genetic Diversity In A Maize Reciprocal Recurrent Selection Program, Lori L. Hinze, Stephen Kresovich, John D. Nason, Kendall R. Lamkey 2017 United States Department of Agriculture

Population Genetic Diversity In A Maize Reciprocal Recurrent Selection Program, Lori L. Hinze, Stephen Kresovich, John D. Nason, Kendall R. Lamkey

Kendall R Lamkey

The genetic structures of the Iowa Corn Borer Synthetic #1 (CB) and Iowa Stiff Stalk Synthetic (SS) maize (Zea mays L.) populations are important because these populations serve as the model for development of modern commercial hybrids. In 1949, CB and SS were used to start a reciprocal recurrent selection (RRS) breeding program at Iowa State University. This study was conducted to analyze more thoroughly the genetic diversity within this RRS program and illustrate how the RRS program has changed over time at the molecular level. The progress of this program was measured by analyzing the variation at 86 SSR ...


Maize Breeding, J. S. C. Smith, O. S. Smith, Kendall R. Lamkey 2017 Pioneer Hi-Bred International, Inc.

Maize Breeding, J. S. C. Smith, O. S. Smith, Kendall R. Lamkey

Kendall R Lamkey

Maize (Zea mays L.) is a remarkable plant. Human societies depend upon maize for food, health, scientific knowledge, economic growth, culture and spirituality. Maize breeders have improved productivity through selection on phenotype. Future improvements in maize productivity will require more effective utilization of genetic resources including direct selection upon genotype. Success will require a greater understanding of the complex biology of quantitative traits and a more thorough evaluation of the broader genetic base of maize. Maize breeders are fortunate and privileged to work with a species that encompasses a broad array of diversity and which provides a rich source of ...


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