Microbiology Commons^™

A Comprehensive Analysis Of Antibiotic Resistance Genes In The Giant Panda Gut, Feilong Deng, Yanhua Han, Yushan Huang, Desheng Li, Jianmin Chai, Linhua Deng, Ming Wei, Kai Wu, Huabin Zhao, Guan Yang, Jiangchao Zhao, Ying Li, Chengdong Wang

Animal Science Faculty Publications and Presentations

In this study, we have successfully constructed a comprehensive database of metagenome-assembled genomes (MAGs) pertaining to the gut microbiota of the giant panda. Through our analysis, we have identified significant reservoirs of antibiotic resistance genes (ARGs), namely Escherichia coli, Citrobacter portucalensis, and Klebsiella pneumoniae. Furthermore, we have elucidated the primary contributors to ARGs, including Streptococcus alactolyticus and Clostridium SGBP116, in both captive and wild pandas. Additionally, our findings have demonstrated a higher prevalence of ARGs in the metagenome, with notable expression of the RPOB2 gene in S. alactolyticus. Crucially, 1217 ARGs shared homology with human gut …

Detection Of Dsrab Operon Expression In Desulfotalea Psychrophila Cells Subjected To Simulated Martian Conditions Of Temperature And Regolith's Sulphate Minerals Composition, Sergio Mosquera, Mack Ivey, Vincent F. Chevrier

Biological Sciences Faculty Publications and Presentations

Discoveries of transient liquid water in the Martian polar caps and the presence of liquid lakes and subsurface oceans in icy satellites have increased the interest of scientists in the capabilities of terrestrial extremophiles to grow and remain metabolically active in these extreme environments. The principal goal of this research is to understand the metabolic capacity of the anaerobic psychrophile, Desulfotalea psychrophila, cultured at subfreezing temperatures in media containing various concentrations of sulphate minerals. In this regard, our experiments focused on the detection of D. psychrophila survival and active metabolism, employing a biochamber that can recreate Martian temperatures. Using …

Exploring The Potential Of Tesla Valve For Filtering And Sorting Microscale Active Swimmers: A Computational Study, Ariel Rogers, Zhiyao He, Yong Wang

Physics Faculty Publications and Presentations

It is well-known that a Tesla valve allows fluids to flow unidirectionally without moving parts; however, how Tesla valves interact with active matters and the potential applications of Tesla valves in biology remain largely unexplored. Here, we present a computational study on the potential use of Tesla valves for filtering and sorting microscale active swimmers such as bacteria. We investigated the behavior of microscale swimmers passing through the Tesla valve at different linear and angular velocities using numerical simulations and quantified the diodicity of the Tesla valve for active swimmers. Our results demonstrate that the Tesla valve can effectively filter …

The Pseudomonas Syringae Pv. Tomato Dc3000 Effector Hopd1 Interferes With Cellular Dynamics Associated With The Function Of The Plant Immune Protein Atnhr2b, Luis Francisco Marin-Ponce, Catalina Rodriguez-Puerto, Perla Rocha-Loyola, Clemencia M. Rojas

Entomology and Plant Pathology Faculty Publications and Presentations

The plant pathogenic bacterium Pseudomonas syringae pv. tomato DC3000 (Pst DC3000) causes disease in tomato, in the model plant Arabidopsis thaliana, and conditionally in Nicotiana benthamiana. The pathogenicity of Pst DC3000 is mostly due to bacterial virulence proteins, known as effectors, that are translocated into the plant cytoplasm through the type III secretion system (T3SS). Bacterial type III secreted effectors (T3SEs) target plants physiological processes and suppress defense responses to enable and support bacterial proliferation. The Pst DC3000 T3SE HopD1 interferes with plant defense responses by targeting the transcription factor NTL9. This work shows that HopD1 also targets the …

Persistence Of Salmonella Enterica Subsp. Enterica Ser. Javiana, Listeria Monocytogenes, And Listeria Innocua In Hydroponic Nutrient Solution, Gayatri R. Dhulappanavar, Kristen E. Gibson

Food Science Faculty Publications and Presentations

This study aimed to determine the persistence of Salmonella Javiana, Listeria monocytogenes, and Listeria innocua in nonsterile, hydroponic nutrient solution (NS) at 15, 25, 30, and 37°C over a 21-day period to mimic time from seedling to mature lettuce. Bacteria were inoculated in modified Hoagland's NS at 106 CFU/mL and maintained at 15, 25, 30, and 37°C. Samples were collected at various time points, and bacteria were quantified. A mixed model was used to determine the effect of bacteria type, time (day), and temperature on bacteria concentration (log CFU/mL). The least-squares means were calculated to compare the mean log …

Potent Bile Acid Microbial Metabolites Modulate Clostridium Perfringens Virulence, Tahrir Jatli Alenezi, Ying Fu, Bilal Alrubaye, Thamer Alanazi, Ayidh Almansour, Hong Wang, Xiaolun Sun

Poultry Science Faculty Publications and Presentations

Clostridium perfringens is a versatile pathogen, inducing diseases in the skin, intestine (such as chicken necrotic enteritis (NE)), and other organs. The classical sign of NE is the foul smell gas in the ballooned small intestine. We hypothesized that deoxycholic acid (DCA) reduced NE by inhibiting C. perfringens virulence signaling pathways. To evaluate the hypothesis, C. perfringens strains CP1 and wild-type (WT) HN13 and its mutants were cultured with different bile acids, including DCA and isoallolithocholic acid (isoalloLCA). Growth, hydrogen sulfide (H₂S) production, and virulence gene expression were measured. Notably, isoalloLCA was more potent in reducing growth, H …

Editorial: Parasitism: The Good, The Bad And The Ugly, Marco A. Juarez-Estrada, Danielle Graham, Xochitl Hernandez-Velasco, Guillermo Tellez-Isaias

Poultry Science Faculty Publications and Presentations

Editorial on the Research Topic

Parasitism: the good, the bad and the ugly

Predicting Stringent Quantiferon-Tb Gold Plus Conversions In Contacts Of Tuberculosis Patients, Sheng-Wei Pan, Donald G. Catanzaro, Marva Seifert, Rehan Syed, Naomi Hillery, Mei-Lin Ho, Valeriu Crudu, Elena Tudor, Nelly Ciobanu, Alexandru Codreanu, Antonino Catanzaro, Timonthy C. Rodwell

Biological Sciences Faculty Publications and Presentations

Objectives

Methods

Results

The Bactericidal Activity Of A Novel Aneurinibacillus Aneurinilyticus Isolate Effectively Controls Foodborne Pathogens Campylobacter Jejuni And Listeria Monocytogenes, Peter M. Rubinelli, Rohana Liyanage, Jackson Lay, Jennifer C. Acuff

Chemistry & Biochemistry Faculty Publications and Presentations

Human zoonotic infection with Campylobacter is a major cause of gastroenteritis in the United States and worldwide. Listeria monocytogenes causes a potentially fatal infection in humans and is often attributed to contaminated food. Genetic typing has demonstrated that Campylobacter infection is often associated with the consumption of contaminated poultry products, with Campylobacter often colonizing the poultry gastrointestinal tract, while listeriosis is commonly associated with the consumption of contaminated ready-to-eat (RTE) foods. In this study, a strain of endospore-forming bacterium (strain NH) that is bactericidal towards the human food pathogens Campylobacter jejuni and Listeria monocytogenes was identified and characterized. Transwell experiments …

Effect Of Bovine Respiratory Disease On The Respiratory Microbiome: A Meta-Analysis, Samantha Howe, Beth Kegley, Jeremy Powell, Sicheng Chen, Jiangchao Zhao

Animal Science Faculty Publications and Presentations

Background: Bovine respiratory disease (BRD) is the most devastating disease affecting beef and dairy cattle producers in North America. An emerging area of interest is the respiratory microbiome’s relationship with BRD. However, results regarding the effect of BRD on respiratory microbiome diversity are conflicting.

Results: To examine the effect of BRD on the alpha diversity of the respiratory microbiome, a meta-analysis analyzing the relationship between the standardized mean difference (SMD) of three alpha diversity metrics (Shannon’s Diversity Index (Shannon), Chao1, and Observed features (OTUs, ASVs, species, and reads) and BRD was conducted. Our multi-level model found no difference in Chao1 …

Aquatic Peptide: The Potential Anti-Cancer And Anti-Microbial Activity Of Ge18 Derived From Pathogenic Fungus Aphanomyces Invadans, Manikandan Velayutham, P. Snega Priya, Purabi Sarkar, Raghul Murugan, Bader O. Almutairi, Selvaraj Arokiyaraj, Zulhisyam Abdul Kari, Guillermo Tellez-Isaias, Ajay Guru, Jesu Arockiaraj

Poultry Science Faculty Publications and Presentations

Small molecules as well as peptide-based therapeutic approaches have attracted global interest due to their lower or no toxicity in nature, and their potential in addressing several health complications including immune diseases, cardiovascular diseases, metabolic disorders, osteoporosis and cancer. This study proposed a peptide, GE18 of subtilisin-like peptidase from the virulence factor of aquatic pathogenic fungus Aphanomyces invadans, which elicits anti-cancer and anti-microbial activities. To understand the potential GE18 peptide-induced biological effects, an in silico analysis, in vitro (L6 cells) and in vivo toxicity assays (using zebrafish embryo), in vitro anti-cancer assays and anti-microbial assays were performed. The outcomes of …

Long-Term Impacts Of Conservation Pasture Management In Manuresheds On System-Level Microbiome And Antibiotic Resistance Genes, Mitiku Mihiret Seyoum, Amanda Ashworth, Kristina M. Feye, Steven C. Ricke, Phillip R. Owens, Philip A. Moore Jr., Mary Savin

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Animal manure improves soil fertility and organic carbon, but long-term deposition may contribute to antibiotic resistance genes (ARGs) entering the soil-water environment. Additionally, long-term impacts of applying animal manure to soil on the soil-water microbiome, a crucial factor in soil health and fertility, are not well understood. The aim of this study is to assess: (1) impacts of long-term conservation practices on the distribution of ARGs and microbial dynamics in soil, and runoff; and (2) associations between bacterial taxa, heavy metals, soil health indicators, and ARGs in manures, soils, and surface runoff in a study following 15 years of continuous …

Past And Ongoing Field-Based Studies Of Myxomycetes, Steven L. Stephenson

Biological Sciences Faculty Publications and Presentations

Evidence from molecular studies indicates that myxomycetes (also called myxogastrids or plasmodial slime molds) have a long evolutionary history, and the oldest known fossil is from the mid-Cretaceous. However, they were not “discovered” until 1654, when a brief description and a woodcut depicting what is almost certainly the common species Lycogala epidendrum was published. First thought to be fungi, myxomycetes were not universally recognized as completely distinct until well into the twentieth century. Biodiversity surveys for the group being carried out over several years are relatively recent, with what is apparently the first example being carried out in the 1930s. …

Roost Selection By Synanthropic Bats In Rural Kenya: Implications For Human-Wildlife Conflict And Zoonotic Pathogen Spillover, Reilly T. Jackson, Paul W. Webala, Joseph G. Ogola, Tamika J. Lunn, Kristian M. Forbes

Biological Sciences Faculty Publications and Presentations

Many wildlife species are synanthropic and use structures built by humans, creating a high-risk interface for human–wildlife conflict and zoonotic pathogen spillover. However, studies that investigate features of urbanizing areas that attract or repel wildlife are currently lacking. We surveyed 85 buildings used by bats and 172 neighbouring buildings unused by bats (controls) in southeastern Kenya during 2021 and 2022 and evaluated the role of microclimate and structural attributes in building selection. We identified eight bat species using buildings, with over 25% of building roosts used concurrently by multiple species. Bats selected taller cement-walled buildings with higher water vapour pressure …

The Unique Gut Microbiome Of Giant Pandas Involved In Protein Metabolism Contributes To The Host's Dietary Adaption To Bamboo, Feilong Deng, Chengdong Wang, Desheng Li, Yunjuan Peng, Linhua Deng, Yunxiang Zhao, Zhihao Zhang, Ming Wei, Kai Wu, Jiangchao Zhao, Ying Li

Animal Science Faculty Publications and Presentations

Background

The gut microbiota of the giant panda (Ailuropoda melanoleuca), a global symbol of conservation, are believed to be involved in the host’s dietary switch to a fibrous bamboo diet. However, their exact roles are still largely unknown.

Results

In this study, we first comprehensively analyzed a large number of gut metagenomes giant pandas (n = 322), including 98 pandas sequenced in this study with deep sequencing (Illumina) and third-generation sequencing (nanopore). We reconstructed 408 metagenome-assembled genomes (MAGs), and 148 of which (36.27%) were near complete. The most abundant MAG was classified as Streptococcus alactolyticus. A …

Editorial: High-Impact Respiratory Rna Virus Diseases, Victor Manuel Patrone-García, Inkar Castellanos-Huerta, Guillermo Tellez-Isaias

Poultry Science Faculty Publications and Presentations

Editorial on the Research Topic

High-impact respiratory RNA virus diseases

Securing Rice Safety Through Innovative Radiative Heat Treatment And Proper Storage, Faith Achieng Ouma

Graduate Theses and Dissertations

Securing the microbial safety of rice is a rising priority within the food industry, especially when used as an ingredient to manufacture ready-to-eat, minimally-processed products. Mold contamination is typically the most problematic for rice because certain species of Aspergillus produce toxic secondary metabolites known as aflatoxins, rendering the grain unfit for human and animal consumption. The objectives of this study are to: (1) investigate the effectiveness of using high-power (915 MHz frequency), short-duration microwaves (MWs) to inactivate microbes on rough rice; (2) use a three-level screening design to determine which storage factors, such as temperature, relative humidity (RH), storage duration, …

Radiofrequency And Gaseous Technologies For Enhancing The Microbiological Safety Of Low Moisture Food Ingredients, Surabhi Wason

Graduate Theses and Dissertations

High heat resistance and long survival of Salmonella in low moisture food ingredients (LMFIs) such as spices and seeds are concerning as they are typically consumed without cooking. Therefore, it is challenging to effectively inactivate pathogenic bacteria without negatively impacting the quality of the treated product. This dissertation aimed to develop and evaluate novel intervention technologies: in-package radiofrequency steaming and non-thermal gaseous technologies to improve the microbial safety of LMFIs. The dissertation can be divided into three parts. The first part of this dissertation on the thermal inactivation kinetics of Salmonella and a surrogate, Enterococcus faecium NRRL B-2354on black pepper …

Horizontal Transfer Of Probable Chicken-Pathogenicity Chromosomal Islands Between Staphylococcus Aureus And Staphylococcus Agnetis, Douglas D. Rhoads, Jeff Pummil, Nnamdi S. Ekesi, Adnan A.K. Alrubaye

Cell and Molecular Biology Faculty Publications and Presentations

Staphylococcus agnetis is an emerging pathogen in chickens but has been most commonly isolated from sub-clinical mastitis in bovines. Previous whole-genome analyses for known virulence genes failed to identify determinants for the switch from mild ductal infections in cattle to severe infections in poultry. We now report identification of a family of 15 kbp, 17–19 gene mobile genetic elements (MGEs) specific to chicken osteomyelitis and dermatitis isolates of S. agnetis. These MGEs can be present in multiple copies per genome. The MGE has been vectored on a Staphylococcus phage that separately lysogenized two S. agnetis osteomyelitis strains. …

Silver Ions Inhibit Bacterial Movement And Stall Flagellar Motor, Benjamin Russell, Ariel Rogers, Ryan Yoder, Matthew Kurilich, Venkata Rao Krishnamurthi, Jingy Chen, Yong Wang

Physics Faculty Publications and Presentations

Silver (Ag) in different forms has been gaining broad attention due to its antimicrobial activities and the increasing resistance of bacteria to commonly prescribed antibiotics. However, various aspects of the antimicrobial mechanism of Ag have not been understood, including how Ag affects bacterial motility, a factor intimately related to bacterial virulence. Here, we report our study on how Ag⁺ ions affect the motility of E. coli bacteria using swimming, tethering, and rotation assays. We observed that the bacteria slowed down dramatically by >70% when subjected to Ag⁺ ions, providing direct evidence that Ag⁺ ions inhibit the motility …

The Effects Of Salt And Temperature On Three Methanogen Species: Implications For Mars, Katy Dunlap

Biological Sciences Undergraduate Honors Theses

The question of whether life has ever existed on Mars – either in the past or currently – has been pursued for decades. This debate has been prompted by a variety of discoveries regarding similarities between Mars and Earth and more recently concerns over human extinction. Mars, like Earth, once had large amounts of water, a key ingredient for life. H₂O exists on Mars in various forms now, and it is theorized that there is liquid water beneath the surface as well. Mars also contains salt and is very cold at its surface, pointing researchers towards the idea …

Understanding The Role Of Heterodisulfide Reductase During Nitrogen Fixation By Methanosarcina Acetivorans, Grant Shelnut

Biological Sciences Undergraduate Honors Theses

Methanosarcina acetivorans is a methanogenic archaeon (methanogen) that is important for several processes in our biosphere. A feature of interest within this methanogen is the enzyme nitrogenase which catalyzes the reduction of unusable dinitrogen gas (N₂) into a usable form of nitrogen, ammonia (NH₃). How electrons are transferred within M. acetivorans to nitrogenase during N₂ reduction is unknown. Heterodisulfide reductase (Hdr) is a key enzyme known to reduce the electron carrier protein ferredoxin, which is a direct electron donor to nitrogenase in bacteria. I hypothesized that cytoplasmic HdrA2B2C2 functions in electron transfer to nitrogenase and …

An Ecological Perspective Of American Rodent-Borne Orthohantavirus Surveillance, Nathaniel Mull

Graduate Theses and Dissertations

Orthohantaviruses are a global group of viruses found primarily in rodents, though several viruses have also been found in shrews and moles. Many rodent-borne orthohantaviruses are capable of causing one of several diseases in humans, and the mortality associated with these diseases ranges from < 0.1% - 50% depending on the specific etiological virus. In North and South America, orthohantavirus research was ignited by an outbreak of severe disease in the Four Corners region of the United States in 1993. However, despite the discovery of over 20 orthohantaviruses in the Americas, our understanding of orthohantavirus ecology and virus-host dynamics in this region is still limited, and orthohantavirus surveillance is generally restricted in scope to select regions and small portions of host distributional ranges. In Chapter I, I present a literature review on the current understanding of American rodent-borne orthohantavirus ecology. This review focused on under-studied orthohantaviruses, addressing gaps in knowledge by extrapolating information from well-studied orthohantaviruses, general rodent ecology, and occassionally from Eurasian orthohantavirus-host ecology. There were several key conclusions generated from this review that warrant further research: 1) the large number of putative orthohantaviruses and gaps in orthohantavirus evolution necessitate further surveillance and characterization, 2) orthohantavirus traits differ and are more generalizable based on host taxonomy rather than geography, and 3) orthohantavirus host species are disproportionately found in grasslands and disturbed habitats. In Chapter II, I present a prioritized list of rodent species to target for orthohantavirus surveillance based on predictive modeling using machine learning. Probable orthohantavirus hosts were predicted based on traits of known orthohantavirus hosts using two different types of evidence: RT-PCR and virus isolation. Predicted host distributions were also mapped to identify geographic hotspots to spatially guide future surveillance efforts. In Chapter III, I present a framework for understanding and predicting orthohantavirus traits based on reservoir host phylogeny, as opposed to the traditional geographic dichotomy used to group orthohantaviruses. This framework establishes three distinct orthohantavirus groups: murid-borne orthohantaviruses, arvicoline-borne orthohantaviruses, and non-arvicoline cricetid-borne orthohantaviruses, which differ in several key traits, including the human disease they cause, transmission routes, and virus-host fidelity. In Chapter IV, I compare rodent communities and orthohantavirus prevalence among grassland management regimes. Sites that were periodically burned had high rodent diversity and a high proportion of grassland species. However, rodent seroprevalence for orthohantavirus was also highest in burned sites, representing a trade-off in habitat management outcomes. The high seroprevalence in burned sites is likely due to the robust populations supported by the high quality habitat resulting from prescribed burning. In Chapters V and VI, I describe Ozark virus and Sager Creek virus, two novel orthohantaviruses discovered from specimens collected during Chapter IV. Both chapters report full genome sequences of the respective viruses and compare both nucleotide and protein phylogenies with related orthohantaviruses. Additionally in Chapter VI, I support the genetic analyses with molecular and ecological characterizations, including seasonal fluctuations in host abundance, correlates of prevalence, evidence of virus shedding, and information on host cell susceptibility to Sager Creek virus.

Fulfilling Koch’S Postulates And Evaluation Of Different Administration Routes In Poults Challenged With Streptococcus Gallolyticus, Latasha Gray

Graduate Theses and Dissertations

Streptococcus gallolyticus (SG) is a Gram-positive found as commensal gut flora in animals and humans. SG has been associated with acute mortality in poults 2 to 3 weeks of age, with lesions mainly consisting of splenomegaly, hepatomegaly, and pericarditis. The objective of this thesis was to reproduce disease in poults caused by SG recovered from clinical field isolates and evaluate different routes of administration. Three field isolates from geographically disparate areas in Arkansas and Missouri were used for the experiments contained in this thesis. Antibiotic sensitives of the three field isolates revealed sensitivity to penicillin as well as a wide …

Metagenomic And Meta-Transcriptomic Analysis Reveal The Colonization And Expression Profile Of Probiotic Strains In Humans And Animals, Yunjuan Peng, Routing Chen, Zhihao Zhang, Rui Jin, Ting Xe, Xinting Liu, Jianmin Chai, Samantha Howe, Jiangchao Zhao, Ying Li, Feilong Deng

Animal Science Faculty Publications and Presentations

In humans and animals, probiotics are widely accepted as crucial for host health and growth. The investigation of the probiotic colonization and expression of probiotics in the host is beneficial for proper usage of probiotics and isolation of indigenous probiotics. In this study, we analyzed commonly used probiotic strains in the intestines/rumen of humans and animals by analyzing metagenomic and paired meta-transcriptomic data from the gut or rumen microbiome of humans (n = 13), pigs (n = 6), chickens (n = 6), cattle (n = 14), sheep (n = 10), and mice (n = …

Antimicrobial Resistance Profile Of Escherichia Coli Isolated From Poultry Litter, M. J. Khong, A. M. Snyder, M. M. Young, N. L. Barbieri, S. L. Weimer

Poultry Science Faculty Publications and Presentations

Antimicrobial resistance is a threat to animal and human health. As a commensal and zoonotic bacterium, Escherichia coli has the potential to be a pathogenic source of antimicrobial resistance. The purpose of this study aimed to investigate the antimicrobial resistance profile of E. coli isolated from litter collected from pens in a broiler chicken experiment. E. coli was isolated from litter samples (n = 68 isolates) of 16 pens housing broilers to d 53 of age. Resistance to 10 antimicrobials was observed by disc diffusion. The presence of 23 antimicrobial and heavy metal resistance genes, O serogroups, and avian pathogenic …

In Silico Analyses Of Diversity And Dissemination Of Antimicrobial Resistance Genes And Mobile Genetics Elements, For Plasmids Of Enteric Pathogens, Suad Algarni, Jing Han, Dereje D. Gudeta, Bijay K. Khajanchi, Steven C. Ricke, Young Min Kwon, Douglas D. Rhoads, Steven L. Foley

Animal Science Faculty Publications and Presentations

Introduction: The antimicrobial resistance (AMR) mobilome plays a key role in the dissemination of resistance genes encoded by mobile genetics elements (MGEs) including plasmids, transposons (Tns), and insertion sequences (ISs). These MGEs contribute to the dissemination of multidrug resistance (MDR) in enteric bacterial pathogens which have been considered as a global public health risk.

Methods: To further understand the diversity and distribution of AMR genes and MGEs across different plasmid types, we utilized multiple sequence-based computational approaches to evaluate AMR-associated plasmid genetics. A collection of 1,309 complete plasmid sequences from Gammaproteobacterial species, including 100 plasmids from each of the following …

The Role Of Microbiota-Biotransformed Bile Acid Metabolites On Campylobacter Jejuni- And Clostridium Perfringens-Infection, Ying Fu

Graduate Theses and Dissertations

Campylobacter jejuni (C. jejuni) and Clostridium perfringens (C. perfringens) are two leading pathogenic bacteria responsible for both human and animal diseases. In chapters Ⅱ to Ⅳ, I presented an overview of current knowledge on the role of immune response, microbiota, bile acids and their microbial metabolites on campylobacteriosis, and C. perfringens induced necrotic diseases.In chapter Ⅴ, I investigated effects of deoxycholic acid-modulated anaerobes (DCA-Anaero) on attenuating chicken transmission-exacerbated campylobacteriosis. SPF Il10-/- mice were gavaged with clindamycin for 7 days followed by infected with three C. jejuni strains, Cj-P0 (C. jejuni AR101), Cj-P1 (from chicken pre-infected with C. jejuni AR101), and …

The Antimicrobial Resistance Plasmid Mobilome Of Salmonella Enterica And Related Enteric Species And Factors That Influence The Transfer Efficiency., Suad Algarni

Graduate Theses and Dissertations

The dynamic distribution of antimicrobial resistance genes in Salmonella enterica is considered a public health risk. S. enterica is one of the most important etiological agents of foodborne illness and has a critical impact on global human health. In S. enterica and related species, mobile genetic elements (MGEs) serve as primary vehicles for the dissemination of antibiotic resistance genes in the bacterial evolution. This dissemination can be impacted by different selective pressures that leads to diverse antibiotic response phenotypes. This project focusses on the dynamics of antimicrobial resistance genes, particularly exploring the transfer efficiency of multidrug resistance plasmids in S. …

Optimization Of Clostridium Septicum Antigen Production And Evaluation Of Vaccine Administration Parameters For A Candidate Bacterin-Toxoid To Prevent Dermatitis In Commercial Turkeys, Aaron Forga

Graduate Theses and Dissertations

The objective of this thesis was to optimize the hemolytic activity of two isolates of Clostridium septicum to evaluate if hemolytic titer of C. septicum antigen at time of formalin inactivation corresponded to increased serum antibody titer to the C. septicum alpha-toxin of turkeys immunized with an experimental formalin inactivated bacterin-toxoid vaccine. Chapter 1 provides a brief overview of the thesis. Chapter 2 consists of a literature review focused on clostridial dermatitis, specifically C. septicum-associated dermatitis (cellulitis) that affects commercial turkeys. Chapter 3 outlines our attempts to optimize an experimental autogenous bacterin-toxoid vaccine as a potential strategy to mitigate clostridial …