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Genetic Characteristics Required In Dairy And Beef Cattle For Temperate Grazing Systems, F. Buckley, C. Holmes, M. G. Keane

IGC Proceedings (1997-2023)

Key points

1. Only about 10% of the world’s milk is produced from grazing systems. Consequently the majority of dairy cattle have not been selected under grazing, nor on seasonal systems. This is not true for beef cattle, for which the majority, especially the dams, are managed under seasonal grazing systems.

2. In grazing systems daily feed intake is limited to lower levels than are achievable on concentrate plus conserved forage rations. Consequently, cows most suited to grazing environments are likely to have a lower genetic potential for milk production than cows selected in high concentrate systems, to minimise their relative energy …

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Alzheimer’S Disease Genetics And Short-Chain Fatty Acid Treatment In Studies Of The Murine Gut Microbiome, Diana Zajac

Theses and Dissertations--Physiology

Elucidating the relationship of the gut microbiome in Alzheimer's Disease (AD) risk and pathogenesis is an area of intense interest. Since 60 to 80% of AD risk is related to genetics and APOE alleles represent the most impactful genetic risk factors for AD, their mechanism(s) of action are under intense scrutiny.

First, I conducted a study on APOE targeted replacement mice to investigate the impact of APOE alleles on the murine gut microbiome. The relative abundance of bacteria from the family Ruminococacceae and related genera increased with APOE2 status. The relative abundance of the class Erysipelotrichia increased with APOE4 status, …

Molecular Genetic Studies Of Horses, Especially With Reference To Aggrecan And Dwarfism, John Edmund Eberth

Theses and Dissertations--Veterinary Science

This work consists of studies on dwarfism in Miniature horses and a study on breakdowns in Thoroughbreds in relation to gene aggrecan. A correction of the description and designation of D3 dwarf variant in aggrecan (ACAN) from the master’s thesis Chondrodysplasia-like dwarfism in the Miniature horse (2013). Commercial sequencing showed previous sequencing reads presented an artifact and not a single base deletion. Analysis showed a single base missense mutation in exon 8 identified as D3* was the actual cause. Multiple alleles of ACAN associated with chondrodysplastic dwarfism in Miniature horses by Eberth et al. (2018), corrected the …

The Low Abundance Of Cpg In The Sars-Cov-2 Genome Is Not An Evolutionarily Signature Of Zap, Ali Afrasiabi, Hamid Alinejad-Rokny, Azad Khosh, Mostafa Rahnama, Nigel Lovell, Zhenming Xu, Diako Ebrahimi

Plant Pathology Faculty Publications

The zinc finger antiviral protein (ZAP) is known to restrict viral replication by binding to the CpG rich regions of viral RNA, and subsequently inducing viral RNA degradation. This enzyme has recently been shown to be capable of restricting SARS-CoV-2. These data have led to the hypothesis that the low abundance of CpG in the SARS-CoV-2 genome is due to an evolutionary pressure exerted by the host ZAP. To investigate this hypothesis, we performed a detailed analysis of many coronavirus sequences and ZAP RNA binding preference data. Our analyses showed neither evidence for an evolutionary pressure acting specifically on CpG …

Apoe Genetics Influence Murine Gut Microbiome, Diana J. Zajac, Stefan J. Green, Lance A. Johnson, Steven Estus

Physiology Faculty Publications

Apolipoprotein E (APOE) alleles impact pathogenesis and risk for multiple human diseases, making them primary targets for disease treatment and prevention. Previously, we and others reported an association between APOE alleles and the gut microbiome. Here, we evaluated effects of APOE heterozygosity and tested whether these overall results extended to mice maintained under ideal conditions for microbiome analyses. To model human APOE alleles, this study used APOE targeted replacement (TR) mice on a C57Bl/6 background. To minimize genetic drift, homozygous APOE3 mice were crossed to homozygous APOE2 or homozygous APOE4 mice prior to the study, and the resulting …

Dairy Cattle Genetics By Environment Interaction Mismatch Contributes To Poor Mitigation And Adaptation Of Grazing Systems To Climate Change Actions In The Peruvian High Andes: A Review, V. M. Velez Marroquin, J. Manhire, R. Garcia Ticllacuri, J. L. Bernal Madrid, C. S. Pinares-Patino

IGC Proceedings (1997-2023)

The high Andes of Peru includes fragile ecosystems. Nevertheless, it plays important ecosystem functions (e.g., biodiversity, water supply for the lowlands, CO₂ sinks in soil, etc). More than 80% of the livestock population of Peru is farmed in this area, supporting the livelihood of approximately 1’400,000 poor families, who are vulnerable to climate change (CC). Climate change in the high Andes is occurring at accelerated rates, compared to lowlands regions. Prevalent factors in the high Andes, such as hypoxia, high UV radiation, climatic extremes, large variation between maximum and minimum temperatures, seasonality in rainfall (determining highly seasonal forage growth) …

Achievements And Perspectives In The Breeding Of Tropical Grasses And Legumes, John W. Miles

IGC Proceedings (1997-2023)

Pasture and forage plant breeding is complicated by the perennial nature of the plants, the diversity of environments in which improved cultivars will be used, and the complex criteria of merit involved, criteria that necessarily include some measure of impact on the efficiency of animal production. While pasture plant breeding in the temperate zone is a demonstrably productive activity, the record of success for the tropical species -- "success" measured by release and adoption of bred cultivars -- is less convincing, in spite of four decades of activity in numerous public sector breeding programs and a large published literature. The …

Alfalfa, J. H. Bouton

IGC Proceedings (1997-2023)

Cultivated alfalfa or lucerne (Medicago sativa spp. sativa) is the most important forage legume in the world with approximately 32 million hectares cultivated mainly in the temperate regions of both the northern and southern hemispheres. Intensive research has been conducted on the management and physiology of the crop and a major seed industry has developed world wide. Since insect and disease pests are numerous in alfalfa, development of cultivars with the proper fall dormancy and a broad genetic base for pest resistance has been pursued in order to provide increased adaptation, persistence, and yield. There has been a …

Editorial For The Genetics Of Alzheimer’S Disease Special Issue: October 2021, Laura Ibanez, Justin B. Miller

Sanders-Brown Center on Aging Faculty Publications

No abstract provided.

Examining Human Apoe Genotype And Sex As Modulators Of Respiratory Plasticity In The Presence And Absence Of Spinal Cord Injury, Lydia Ella Strattan

Theses and Dissertations--Neuroscience

There are over 17,000 new spinal cord injuries (SCIs) every year in the Unites States alone. Almost 60% of these injuries occur at the cervical level, potentially leading to loss of function in a variety of sensory and motor systems including upper and lower limbs, respiratory, and autonomics. In addition to the physical and emotional costs, individuals who experience these higher level injuries also face a massive financial burden, incurring over $1 million in expenses during the first year after injury in addition to substantial yearly costs for the rest of their lifetime. A myriad of therapeutic approaches targeting plasticity …

The P-Glycoprotein Repertoire Of The Equine Parasitic Nematode Parascaris Univalens, Alexander P. Gerhard, Jürgen Krücken, Emanuel Heitlinger, I. Jana I. Janssen, Marta Basiaga, Sławomir Kornaś, Céline Beier, Martin K. Nielsen, Richard E. Davis, Jianbin Wang, Georg Von Samson-Himmelstjerna

Maxwell H. Gluck Equine Research Center Faculty Publications

P-glycoproteins (Pgp) have been proposed as contributors to the widespread macrocyclic lactone (ML) resistance in several nematode species including a major pathogen of foals, Parascaris univalens. Using new and available RNA-seq data, ten different genomic loci encoding Pgps were identified and characterized by transcriptome-guided RT-PCRs and Sanger sequencing. Phylogenetic analysis revealed an ascarid-specific Pgp lineage, Pgp-18, as well as two paralogues of Pgp-11 and Pgp-16. Comparative gene expression analyses in P. univalens and Caenorhabditis elegans show that the intestine is the major site of expression but individual gene expression patterns were not conserved between the two nematodes. In P. …

Genome Diversity And The Origin Of The Arabian Horse, Elissa J. Cosgrove, Raheleh Sadeghi, Florencia Schlamp, Heather M. Holl, Mohammad Moradi-Shahrbabak, Seyed Reza Miraei-Ashtiani, Salma Abdalla, Ben Shykind, Mats H. T. Troedsson, Monika Stefaniuk-Szmukier, Anil Prabhu, Stefania Bucca, Monika Bugno-Poniewierska, Barbara Wallner, Joel Malek, Donald C. Miller, Andrew G. Clark, Douglas F. Antczak, Samantha A. Brooks

Veterinary Science Faculty Publications

The Arabian horse, one of the world's oldest breeds of any domesticated animal, is characterized by natural beauty, graceful movement, athletic endurance, and, as a result of its development in the arid Middle East, the ability to thrive in a hot, dry environment. Here we studied 378 Arabian horses from 12 countries using equine single nucleotide polymorphism (SNP) arrays and whole-genome re-sequencing to examine hypotheses about genomic diversity, population structure, and the relationship of the Arabian to other horse breeds. We identified a high degree of genetic variation and complex ancestry in Arabian horses from the Middle East region. Also, …

Genetic Analysis Of The Endangered Gray Bat Species (Myotis Grisescens), Emma Fitzgerald

Lewis Honors College Capstone Collection

This study attempts to analyze the genetics using specific haplotype sequences of the endangered gray bat to determine genetic events that have happened in the past as well as determining how the species population has changed over time. We were able to conduct a Tajima’s D test to investigate whether a potential bottleneck has occurred. A linear regression of the genetic vs. geographical distance was produced to investigate the patterns of haplotype distribution. The species past distribution was compared to the current distribution using known collected specimens. A map of future predictions was constructed using present and future climate layers …

An Exome-Wide Sequencing Study Of The Goldn Cohort Reveals Novel Associations Of Coding Variants And Fasting Plasma Lipids, Xin Geng, Marguerite R. Irvin, Bertha Hidalgo, Stella Aslibekyan, Vinodh Srinivasasainagendra, Ping An, Alexis C. Frazier-Wood, Hemant K. Tiwari, Tushar Dave, Kathleen Ryan, Jose M. Ordovas, Robert J. Straka, Mary F. Feitosa, Paul N. Hopkins, Ingrid Borecki, Michael A. Province, Braxton D. Mitchell, Donna K. Arnett, Degui Zhi

Epidemiology and Environmental Health Faculty Publications

Background: Associations of both common and rare genetic variants with fasting blood lipids have been extensively studied. However, most of the rare coding variants associated with lipids are population-specific, and exploration of genetic data from diverse population samples may enhance the identification of novel associations with rare variants.

Results: We searched for novel coding genetic variants associated with fasting lipid levels in 894 samples from the Genetics of Lipid Lowering Drugs and Diet Network (GOLDN) with exome-wide sequencing-based genotype data. In single variant tests, one variant (rs11171663 in ITGA7) was associated with fasting triglyceride levels (P = 7.66E-08), …

A Phewas Study Of A Large Observational Epidemiological Cohort Of African Americans From The Regards Study, Xueyan Zhao, Xin Geng, Vinodh Srinivasasainagendra, Ninad Chaudhary, Suzanne Judd, Virginia Wadley, Orlando M. Gutiérrez, Henry Wang, Ethan M. Lange, Leslie A. Lange, Daniel Woo, Frederick W. Unverzagt, Monika Safford, Mary Cushman, Nita Limdi, Rakale Quarells, Donna K. Arnett, Marguerite R. Irvin, Degui Zhi

Epidemiology and Environmental Health Faculty Publications

Background: Cardiovascular disease, diabetes, and kidney disease are among the leading causes of death and disability worldwide. However, knowledge of genetic determinants of those diseases in African Americans remains limited.

Results: In our study, associations between 4956 GWAS catalog reported SNPs and 67 traits were examined among 7726 African Americans from the REasons for Geographic and Racial Differences in Stroke (REGARDS) study, which is focused on identifying factors that increase stroke risk. The prevalent and incident phenotypes studied included inflammation, kidney traits, cardiovascular traits and cognition. Our results validated 29 known associations, of which eight associations were reported for the …

Epigenome-Wide Association Study Of Metabolic Syndrome In African-American Adults, Tomi Akinyemiju, Anh N. Do, Amit Patki, Stella Aslibekyan, Degui Zhi, Bertha Hidalgo, Hemant K. Tiwari, Devin Absher, Xin Geng, Donna K. Arnett, Marguerite R. Irvin

Epidemiology and Environmental Health Faculty Publications

Background: The high prevalence of obesity among US adults has resulted in significant increases in associated metabolic disorders such as diabetes, dyslipidemia, and high blood pressure. Together, these disorders constitute metabolic syndrome, a clinically defined condition highly prevalent among African-Americans. Identifying epigenetic alterations associated with metabolic syndrome may provide additional information regarding etiology beyond current evidence from genome-wide association studies.

Methods: Data on metabolic syndrome and DNA methylation was assessed on 614 African-Americans from the Hypertension Genetic Epidemiology Network (HyperGEN) study. Metabolic syndrome was defined using the joint harmonized criteria, and DNA methylation was assessed using the Illumina HumanMethylation450K Bead …

An Exome-Wide Sequencing Study Of Lipid Response To High-Fat Meal And Fenofibrate In Caucasians From The Goldn Cohort, Xin Geng, Marguerite R. Irvin, Bertha Hidalgo, Stella Aslibekyan, Vinodh Srinivasasainagendra, Ping An, Alexis C. Frazier-Wood, Hemant K. Tiwari, Tushar Dave, Kathleen Ryan, Jose M. Ordovas, Robert J. Straka, Mary F. Feitosa, Paul N. Hopkins, Ingrid Borecki, Michael A. Province, Braxton D. Mitchell, Donna K. Arnett, Degui Zhi

Epidemiology and Environmental Health Faculty Publications

Our understanding of genetic influences on the response of lipids to specific interventions is limited. In this study, we sought to elucidate effects of rare genetic variants on lipid response to a high-fat meal challenge and fenofibrate (FFB) therapy in the Genetics of Lipid Lowering Drugs and Diet Network (GOLDN) cohort using an exome-wide sequencing-based association study. Our results showed that the rare coding variants in ITGA7, SIPA1L2, and CEP72 are significantly associated with fasting LDL cholesterol response to FFB (P = 1.24E-07), triglyceride postprandial area under the increase (AUI) (P = 2.31E-06), and triglyceride postprandial …

Advancing Behavioural Genomics By Considering Timescale, Clare C. Rittschof, Kimberly A. Hughes

Entomology Faculty Publications

Animal behavioural traits often covary with gene expression, pointing towards a genomic constraint on organismal responses to environmental cues. This pattern highlights a gap in our understanding of the time course of environmentally responsive gene expression, and moreover, how these dynamics are regulated. Advances in behavioural genomics explore how gene expression dynamics are correlated with behavioural traits that range from stable to highly labile. We consider the idea that certain genomic regulatory mechanisms may predict the timescale of an environmental effect on behaviour. This temporally minded approach could inform both organismal and evolutionary questions ranging from the remediation of early …

Pleiotropy Of Genetic Variants On Obesity And Smoking Phenotypes: Results From The Oncoarray Project Of The International Lung Cancer Consortium, Tao Wang, Jee-Young Moon, Yiqun Wu, Christopher I. Amos, Rayjean J. Hung, Adonina Tardon, Angeline Andrew, Chu Chen, David C. Christiani, Demetrios Albanes, Erik H. F. M. Van Der Heijden, Eric Duell, Gadi Rennert, Gary Goodman, Geoffrey Liu, James D. Mckay, Jian-Min Yuan, John K. Field, Jonas Manjer, Kjell Grankvist, Lambertus A. Kiemeney, Loic Le Marchand, M. Dawn Teare, Matthew B. Schabath, Mattias Johansson, Melinda C. Aldrich, Michael Davies, Mikael Johansson, Ming-Sound Tsao, Neil Caporaso, Susanne Arnold

Internal Medicine Faculty Publications

Obesity and cigarette smoking are correlated through complex relationships. Common genetic causes may contribute to these correlations. In this study, we selected 241 loci potentially associated with body mass index (BMI) based on the Genetic Investigation of ANthropometric Traits (GIANT) consortium data and calculated a BMI genetic risk score (BMI-GRS) for 17,037 individuals of European descent from the Oncoarray Project of the International Lung Cancer Consortium (ILCCO). Smokers had a significantly higher BMI-GRS than never-smokers (p = 0.016 and 0.010 before and after adjustment for BMI, respectively). The BMI-GRS was also positively correlated with pack-years of smoking (p < 0.001) in smokers. Based on causal network inference analyses, seven and five of 241 SNPs were classified to pleiotropic models for BMI/smoking status and BMI/pack-years, respectively. Among them, three and four SNPs associated with smoking status and pack-years (p < 0.05), respectively, were followed up in the ever-smoking data of the Tobacco, Alcohol and Genetics (TAG) consortium. Among these seven candidate SNPs, one SNP (rs11030104, BDNF) …

Impact Of Home Visit Capacity On Genetic Association Studies Of Late-Onset Alzheimer's Disease, David W. Fardo, Laura E. Gibbons, Shubhabrata Mukherjee, M. Maria Glymour, Wayne Mccormick, Susan M. Mccurry, James D. Bowen, Eric B. Larson, Paul K. Crane

Biostatistics Faculty Publications

INTRODUCTION—Findings for genetic correlates of late-onset Alzheimer's disease (LOAD) in studies that rely solely on clinic visits may differ from those with capacity to follow participants unable to attend clinic visits.

METHODS—We evaluated previously identified LOAD-risk single nucleotide variants in the prospective Adult Changes in Thought study, comparing hazard ratios (HRs) estimated using the full data set of both in-home and clinic visits (n = 1697) to HRs estimated using only data that were obtained from clinic visits (n = 1308). Models were adjusted for age, sex, principal components to account for ancestry, and additional health indicators.

RESULTS …

Clinical And Experimental Studies Of A Novel P525r Fus Mutation In Amyotrophic Lateral Sclerosis, Lisha Kuang, Marisa Kamelgarn, Alexandra Arenas, Jozsef Gal, Deborah Taylor, Weiming Gong, Martin Brown, Daret St. Clair, Edward J. Kasarskis, Haining Zhu

Molecular and Cellular Biochemistry Faculty Publications

Objective: To describe the clinical features of a novel fused in sarcoma (FUS) mutation in a young adult female amyotrophic lateral sclerosis (ALS) patient with rapid progression of weakness and to experimentally validate the consequences of the P525R mutation in cellular neuronal models.

Methods: We conducted sequencing of genomic DNA from the index patient and her family members. Immunocytochemistry was performed in various cellular models to determine whether the newly identified P525R mutant FUS protein accumulated in cytoplasmic inclusions. Clinical features of the index patient were compared with 19 other patients with ALS carrying the P525L mutation in the same …

Consequences Of Severe Habitat Fragmentation On Density, Genetics, And Spatial Capture-Recapture Analysis Of A Small Bear Population, Sean Mccarthy Murphy, Ben C. Augustine, Wade Allen Ulrey, Joseph Maddox Guthrie, Brian K Scheick, J. Walter Mccown, John J. Cox

Forestry and Natural Resources Faculty Publications

Loss and fragmentation of natural habitats caused by human land uses have subdivided several formerly contiguous large carnivore populations into multiple small and often isolated subpopulations, which can reduce genetic variation and lead to precipitous population declines. Substantial habitat loss and fragmentation from urban development and agriculture expansion relegated the Highlands-Glades subpopulation (HGS) of Florida, USA, black bears (Ursus americanus floridanus) to prolonged isolation; increasing human land development is projected to cause ≥ 50% loss of remaining natural habitats occupied by the HGS in coming decades. We conducted a noninvasive genetic spatial capture-recapture study to quantitatively describe the …

Alzheimer's Disease Genetics And Abca7 Splicing, Jared B. Vasquez, James F. Simpson, Ryan Harpole, Steven Estus

Physiology Faculty Publications

Both common and rare polymorphisms within ABCA7 have been associated with Alzheimer’s disease (AD). In particular, the rare AD associated polymorphism rs200538373 was associated with altered ABCA7 exon 41 splicing and an AD risk odds ratio of ∼1.9. To probe the role of this polymorphism in ABCA7 splicing, we used minigene studies and qPCR of human brain RNA. We report aberrant ABCA7 exon 41 splicing in the brain of a carrier of the rs200538373 minor C allele. Moreover, minigene studies show that rs200538373 acts as a robust functional variant in vitro. Lastly, although the ABCA7 isoform with an extended …

Neuropathological And Genetic Correlates Of Survival And Dementia Onset In Synucleinopathies: A Retrospective Analysis, David J. Irwin, Murray Grossman, Daniel Weintraub, Howard I. Hurtig, John E. Duda, Sharon X. Xie, Edward B. Lee, Vivianna M. Van Deerlin, Oscar L. Lopez, Julia K. Kofler, Peter T. Nelson, Gregory A. Jicha, Randy Woltjer, Joseph F. Quinn, Jeffery Kaye, James B. Leverenz, Debby Tsuang, Katelan Longfellow, Dora Yearout, Walter Kukull, C. Dirk Keene, Thomas J. Montine, Cyrus P. Zabetian, John Q. Trojanowski

Sanders-Brown Center on Aging Faculty Publications

Background

Great heterogeneity exists in survival and the interval between onset of motor symptoms and dementia symptoms across synucleinopathies. We aimed to identify genetic and pathological markers that have the strongest association with these features of clinical heterogeneity in synucleinopathies.

Methods

In this retrospective study, we examined symptom onset, and genetic and neuropathological data from a cohort of patients with Lewy body disorders with autopsy-confirmed α synucleinopathy (as of Oct 1, 2015) who were previously included in other studies from five academic institutions in five cities in the USA. We used histopathology techniques and markers to assess the burden of …

Unique Features Of A Global Human Ectoparasite Identified Through Sequencing Of The Bed Bug Genome, Joshua B. Benoit, Zach N. Adelman, Klaus Reinhardt, Amanda Dolan, Monica Poelchau, Emily C. Jennings, Elise M. Szuter, Richard W. Hagan, Hemant Gujar, Jayendra Nath Shukla, Fang Zhu, M. Mohan, David R. Nelson, Andrew J. Rosendale, Christian Derst, Valentina Resnik, Sebastian Wernig, Pamela Menegazzi, Christian Wegener, Nicolai Peschel, Jacob M. Hendershot, Wolfgang Blenau, Reinhard Predel, Paul R. Johnston, Panagiotis Ioannidis, Robert M. Waterhouse, Ralf Nauen, Corinna Schorn, Mark-Christoph Ott, Frank Maiwald, Subba R. Palli

Entomology Faculty Publications

The bed bug, Cimex lectularius, has re-established itself as a ubiquitous human ectoparasite throughout much of the world during the past two decades. This global resurgence is likely linked to increased international travel and commerce in addition to widespread insecticide resistance. Analyses of the C. lectularius sequenced genome (650 Mb) and 14,220 predicted protein-coding genes provide a comprehensive representation of genes that are linked to traumatic insemination, a reduced chemosensory repertoire of genes related to obligate hematophagy, host-symbiont interactions, and several mechanisms of insecticide resistance. In addition, we document the presence of multiple putative lateral gene transfer events. Genome …

The Role Of Rapgap1 In Sxl Activation In Drosophila Melanogaster, Katherine M. Barnes

Lewis Honors College Capstone Collection

The master switch of the sexual differentiation and dosage compensation pathway in Drosophila is the sex lethal gene, Sxl. The early promoter, SxlPe, is activated in females, resulting in female-specific splicing of later transcripts (notably the late Sxl transcript SxlPm), while inactive in males. Chromatin immunoprecipitation (ChIP) assays have previously shown association of two conventionally heterochromatin-localized proteins, HOAP and HP1, at SxlPe, and in situ hybridization as well as RT-PCR assays have confirmed a repressive role for HOAP and both repressive and activating roles for HP1. The mechanism for the activity shift of HP1 is currently unknown. Deletions in the …

Recent Trends In Breeding Of Tropical Grass And Forage Species, J. S. Sandhu, Dinesh Kumar, Vijay Kumar Yadav, Tejveer Singh, R. P. Sah, Auji Radhakrishna

IGC Proceedings (1997-2023)

Germplasm enrichment in major tropical grasses and their characterization for emerging environmental challenges have been major focussed area in the recent past. Breeding efforts in tropical grasses are still limited to few selected species viz. Panicum spp, Cenchrus spp, Pennisetum spp and Bracharia spp and all other grasses use of land races for varietal development through selection have been major source of improvement. The pace of breeding efforts in the tropical grasses have been slowed because of many inherent characteristics viz. apomixis, poor seed set, high photo and thermo sensitivity often creating problem in designing and implementing an effective breeding …

Impact Of Market Forces On Product Quality And Grassland Condition, David L. Michalk, Jianping Wu, Warwick B. Badgery, David R. Kemp

IGC Proceedings (1997-2023)

Meeting demands for livestock products which are predicted to more than double during the next 20 years, is central to the challenge of feeding the world sustainably. Smallholders will play a key role in achieving global security in animal protein. However, this requires a shift from subsistence to market-oriented farming where production efficiency not the number of livestock is the key focus with the aim of producing ‘more from less’. For grassland-based ruminant production, reducing stocking rate from current unsustainable levels under subsistence management is an essential first step to producing more production and profit from fewer animals. This is …

Wolbachia Association With The Tsetse Fly, Glossina Fuscipes Fuscipes, Reveals High Levels Of Genetic Diversity And Complex Evolutionary Dynamics, Rebecca E. Symula, Uzma Alam, Corey L. Brelsfoard, Yineng Wu, Richard Echodu, Loyce M. Okedi, Serap Aksoy, Adalgisa Caccone

Entomology Faculty Publications

BACKGROUND: Wolbachia pipientis, a diverse group of α-proteobacteria, can alter arthropod host reproduction and confer a reproductive advantage to Wolbachia-infected females (cytoplasmic incompatibility (CI)). This advantage can alter host population genetics because Wolbachia-infected females produce more offspring with their own mitochondrial DNA (mtDNA) haplotypes than uninfected females. Thus, these host haplotypes become common or fixed (selective sweep). Although simulations suggest that for a CI-mediated sweep to occur, there must be a transient phase with repeated initial infections of multiple individual hosts by different Wolbachia strains, this has not been observed empirically. Wolbachia has been found in the tsetse fly, Glossina …

Genetic Diversity, Structure, And Recolonization Patterns Of Kentucky Black Bears, John Tyler Hast

University of Kentucky Master's Theses

After nearly a century of absence, the black bear (Ursus americanus) reappeared in Kentucky during the late 20th century and has since increased in number. Recolonization of bears in the southeastern portion of the state was thought to have been caused by emigration of bears from adjacent states into the Commonwealth, while in the south-central area, bears originated, or natural recolonization may have been supplemented by the translocation of 14 individuals into the Big South Fork National River Recreation Area. To investigate the recolonization patterns of bears in Kentucky, I used 20 microsatellite loci to determine the genetic …