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Environmental Microbiology and Microbial Ecology Commons™
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Articles 1 - 30 of 32
Full-Text Articles in Environmental Microbiology and Microbial Ecology
Rainwater Harvesting Systems Metagenomics, Jade Riddle, Julia Parsons
Rainwater Harvesting Systems Metagenomics, Jade Riddle, Julia Parsons
Spring Showcase for Research and Creative Inquiry
Climate change induced water scarcity has led to an increasing interest in non-traditional water sources such as rainwater. However, there are lingering health and safety concerns due to the lack of research into the microbial communities contained within collection systems. To address this gap, water samples were collected from rain barrels around northern Virginia for microbial analysis. Each microbe within the sample has a unique genome subject to DNA testing. Environmental DNA was prepared from the collected water samples. To characterize the microbial community, both targeted sequencing and whole genome sequencing approaches were used. Using targeted sequencing of the 16s …
Mechanistic Examination Of Protist-Mediated Plant Growth Through The Comparative Development Of Medicago Truncatula, Shane Connolly
Mechanistic Examination Of Protist-Mediated Plant Growth Through The Comparative Development Of Medicago Truncatula, Shane Connolly
University Scholar Projects
Protists are known to increase plant growth through two main mechanisms: the microbial loop and the alteration of the root microbiome. The microbial loop is a nutrient recycling method in which protists provide inorganic nitrogen ions to the plant. Alteration of root microbiome leads to the removal of plant pathogens and shifting communities towards plant growth-promoting bacteria (PGPB). This study aimed to elicit which mechanism could produce the largest boost in shoot weight for Medicago truncatula. A series of microcosm experiments were explored in which M. truncatula was grown with variable microbiome structures to allow for mechanism differentiation. The …
Fine-Scale Genetic Structure In Rhizosphere Microbial Communities Associated With Chamaecrista Fasciculata (Fabaceae), Mahboubeh Hosseinalizadeh Nobarinezhad, Lisa E. Wallace
Fine-Scale Genetic Structure In Rhizosphere Microbial Communities Associated With Chamaecrista Fasciculata (Fabaceae), Mahboubeh Hosseinalizadeh Nobarinezhad, Lisa E. Wallace
Biological Sciences Faculty Publications
Soil microbiota of the rhizosphere are an important extension of the plant phenotype because they impact the health and fitness of host plants. The composition of these communities is expected to differ among host plants due to influence by host genotype. Given that many plant populations exhibit fine-scale genetic structure (SGS), associated microbial communities may also exhibit SGS. In this study, we tested this hypothesis using Chamaecrista fasciculata, a legume species that has previously been determined to have significant SGS. We collected genetic data from prokaryotic and fungal rhizosphere communities in association with 70 plants in an area of …
Community Ecology And Disease Dynamics In Pacific Oysters: Unraveling Microbiome-Pathogen Interactions In The Wild, Victoria E. Cifelli
Community Ecology And Disease Dynamics In Pacific Oysters: Unraveling Microbiome-Pathogen Interactions In The Wild, Victoria E. Cifelli
Cal Poly Humboldt theses and projects
In the context of multispecies microbial assemblages, disruptions can occur when there are alterations in host conditions, such as the onset of a disease. Notably, viruses have the potential to reshape a host's microbial community. However, the role of the host's habitat and environment, which could be pivotal in communities with shifting niche space and habitat filters, is often overlooked in host-microbe-pathogen interactions. Recognizing the importance of these factors, I employed a field-based approach to understand microbial community dynamics in the presence of disease. To address the influence of geographical location, I conducted an analysis involving healthy and infected oysters …
Host-Microbe Interactions In Non-Native Estuarine Anemones: Biogeography And Temperature, Parker K. Lund
Host-Microbe Interactions In Non-Native Estuarine Anemones: Biogeography And Temperature, Parker K. Lund
Cal Poly Humboldt theses and projects
Non-native species are increasing in prevalence around the world, resulting in negative economic and ecological impacts. However, the broad distributions of non-native species also offer a system for investigating the response of host-associated microbial communities to environmental factors across a range of ecological scales. At the broadest scale, I investigated the geography of microbial communities in the non-native estuarine anemone Diadumene lineata on the west coast of the United States of America. Across latitudes, microbial community composition was very similar and displayed a high percentage of Klebsiella spp. at all sites. However, the communities in California tended to exhibit higher …
Investigating The Effectiveness Of Microplastic Removal And The Relationship Between Microplastics, Bacterial Communities, And Nitrogen Cycling In The Natural Treatment Systems At The Arcata Wastewater Treatment Facility, Fiona Connor
Cal Poly Humboldt theses and projects
This thesis addressed two challenging aspects of microplastic research, including the quantification of microplastics in organic-rich water, and the investigation of how microplastics impact microorganisms and related nutrient-cycling. Two projects were designed and executed to address specific research objectives relating to these broad topics. The first objective was to develop and implement methods to determine the effectiveness of microplastic removal across the natural treatment systems at the Arcata Wastewater Treatment Facility (AWTF). The second objective was to observe how microplastics found in domestic wastewater impact the bacterial communities and nitrogen cycling in freshwater treatment wetland sediment through a bench-scale experiment, …
Microbial Sociality In Biofilms, Swetha Kasetty
Microbial Sociality In Biofilms, Swetha Kasetty
Dartmouth College Ph.D Dissertations
Biofilms are communities of microorganisms attached to surfaces through various self-secreted matrix materials. Biofilms are dynamic communities with extensive interactions between their residents. Microorganisms compete, cooperate, and communicate with each other in biofilms. These ecological interactions determine the emergence or loss of strains/species and are critical in the formation and proliferation of biofilms. Furthermore, most natural biofilms are formed by multiple microbial species and strains and these interactions within the biofilm dramatically influence community composition and structure over time. Microbial interactions also influence clinically relevant outcomes such as antibiotic resistance and host virulence. In this thesis we explore the potential …
The Spatial, Temporal, And Ecological Constraints Of Plant-Host Associated Microbial Communities, Jonathan Dickey
The Spatial, Temporal, And Ecological Constraints Of Plant-Host Associated Microbial Communities, Jonathan Dickey
Doctoral Dissertations
With the development of next generation sequencing technology, ecologists have recently been able to describe microbial communities across a wide array of niches at an accelerated pace. De-novo-based patterns in richness and relative abundance have been described for bacterial and fungal communities in terrestrial, aquatic, and host-associated microhabitats. A recent synthesis has shown that these communities exhibit similar geographical patterns that have been traditionally described for plant and animals. Yet, there is a lack of hypothesis-based research for host-associated microbial communities. Throughout this dissertation, I will address how spatial scale, sequencing resolution, and manipulative rainfall exclusion govern host-associated microbial communities …
Making Sense Of Soil Microbiome Complexity For Plant And Ecosystem Function In A Changing World, Kendall K. Beals
Making Sense Of Soil Microbiome Complexity For Plant And Ecosystem Function In A Changing World, Kendall K. Beals
Doctoral Dissertations
Soils contain the highest biodiversity on Earth. While the importance of the soil microbiome for larger-scale ecological phenomena such as nutrient and carbon cycling, plant growth and plant community dynamics is well-established, the fundamental question of the ecological and evolutionary function of this immense belowground microbial diversity for plant and ecosystem function still remains a great challenge in microbial ecology research. The objective of this dissertation is to understand how the importance of soil microbial community composition for plant and ecosystem function and how changes to soil microbial community composition from climate change-induced disturbance events, specifically fire, influence plant and …
Degradation And Nitrogen Cycling In The Context Of Biodiversity-Ecosystem Function Relationships In The Inquiline Bacterial Community Of Darlingtonia Californica, Megan Teigen
Cal Poly Humboldt theses and projects
Biodiversity-ecosystem function (BEF) research aims to explain how species and their environments interact with each other. Microbial communities engage in vital biogeochemical pathways in a variety of natural ecosystems, and yet there are large knowledge gaps about the specific metabolic pathways in which they are involved. Degradation specifically contributes to nitrogen cycling globally through the breakdown of large organic nitrogen compounds into small inorganic nitrogen that is necessary for the survival of many other organisms. In this study, I focused on the degradative function of the inquiline microbial communities found within the carnivorous pitcher plant, Darlingtonia californica. Darlingtonia grows in …
Soil Microbial Community Dynamics In Response To Prescribed Extreme Fires Following Juniperus Virginiana Invasion In The Loess Canyons Of Nebraska, Julie A. Fowler
Soil Microbial Community Dynamics In Response To Prescribed Extreme Fires Following Juniperus Virginiana Invasion In The Loess Canyons Of Nebraska, Julie A. Fowler
School of Natural Resources: Dissertations, Theses, and Student Research
In Nebraska and other regions of the Great Plains, the conifer Juniperus virginiana (eastern redcedar) is converting grasslands to dense woodlands. This is driven by the interacting drivers of fire suppression, altered grazing regimes, climate change and other anthropogenic factors, impacting the provisioning of ecosystem services. This vegetation state transition modifies water resource regulation and biogeochemical cycles leading to altered edaphic properties including soil microbial community composition. To restore these grasslands and control J. virginiana spread, prescribed extreme burns are implemented as a management tool through local prescribed burn associations. We hypothesized that the alternative state transition to dense J. …
Construction And Analysis Of Three Multi-Partite Synthetic Microbial Communities, Alexander J. Lazzara, Jacob K. Fanning
Construction And Analysis Of Three Multi-Partite Synthetic Microbial Communities, Alexander J. Lazzara, Jacob K. Fanning
Honors Theses
Microbial Communities are of interest to molecular biologists hoping to understand the nature of metabolic interactions between co-existing, or possibly mutualistic, organisms. These interactions are ubiquitous in nature, but understanding the molecular mechanisms involved remains challenging and not well understood. Here, we design three tri-partite microbial circuits based on possible interactions among involved microbes, which are discussed and may suggest mutualistic interactions. Carbon and nitrogen molecular pathways and the intracellular metabolism of each microbe is discussed. We present minimal growth media that will ensure that organisms utilize available resources, which may originate from metabolic processes in neighboring microbes, simulating a …
More Than The Sum Of Their Parts: Building A Framework For Understanding Host-Microbe Interactions In Medicago Sativa, Katherine Mackenzie Moccia
More Than The Sum Of Their Parts: Building A Framework For Understanding Host-Microbe Interactions In Medicago Sativa, Katherine Mackenzie Moccia
Doctoral Dissertations
This dissertation seeks to understand plant-microbe interactions in the agriculturally relevant plant Medicago sativa from three distinct vantage points within microbiology. Within the plant microbiome, we examine how primer usage and the application of peptide nucleic acids impacts 16S and 18S rRNA gene sequencing. In doing so, we design a novel peptide nucleic acid, PNA, and test its impact using multiple primers and sequencing protocols. Once microbial sequencing methodology is established, we generate a synthetic consortium of bacterial isolates from M. sativa leaves and modulate nitrogen levels to better understand microbial structure. Drop out communities, where we remove one member …
The Effect Of Historic Shipwrecks On Sediment Microbiomes In The Northern Gulf Of Mexico, Melissa Brock
The Effect Of Historic Shipwrecks On Sediment Microbiomes In The Northern Gulf Of Mexico, Melissa Brock
Master's Theses
Microorganisms are ubiquitously distributed across all aquatic habitats, but it is the environmental conditions of a habitat that determine which microorganisms can thrive in terms of abundance or metabolic activity. Habitats that experience consistent physical and chemical environmental conditions repeatedly favor specific taxonomic groups which may result in a microbial assemblage that is commonly associated with that habitat (i.e., a core microbiome). Core microbiomes have been identified for a variety of natural marine habitats including methane seeps, wood falls, octocoral, and deep-sea sediments. However, it was unknown if the presence of man-made structures on the seafloor, including historic shipwrecks, also …
Inferred Function And Dynamics Of Microbial Communities From The Northern Gulf Of Mexico, Deepesh Tourani
Inferred Function And Dynamics Of Microbial Communities From The Northern Gulf Of Mexico, Deepesh Tourani
HCNSO Student Theses and Dissertations
Microbial communities, or microbiomes, are the major drivers of global biogeochemical cycles, acting as primary producers and decomposers across the water column in the oceans. Thus, they reflect changes in physicochemical properties and nutrient composition of the ocean. However, this correlation between ecological changes and the function of marine microbiomes is poorly understood. Large-scale oceanic events such as the bottom-water oxygen-depleted zone (i.e., “dead zone”) and the Deepwater Horizon oil spill in the Gulf of Mexico (GoM) render the ecosystem fragile. These events decrease survival rates of pelagic and coastal macrofauna and affect the biodiversity of the region. As part …
Intrinsic Challenges In Ancient Microbiome Reconstruction Using 16s Rrna Gene Amplification, Kirsten Ziesemer, Allison Mann, Krithivasan Sankaranarayanan, Hannes Schroeder, Andrew T. Ozga, Bernd W. Brandt, Egija Zaura, Andrea Waters-Rist, Menno Hoogland, Domingo C. Salazar-Garcia, Mark Aldenderfer, Camilla Speller, Jessica Hendy, Darlene A. Weston, Sandy J. Macdonald, Gavin H. Thomas, Matthew J. Collins, Cecil M. Lewis Jr., Corinne Hofman, Christina Warinner
Intrinsic Challenges In Ancient Microbiome Reconstruction Using 16s Rrna Gene Amplification, Kirsten Ziesemer, Allison Mann, Krithivasan Sankaranarayanan, Hannes Schroeder, Andrew T. Ozga, Bernd W. Brandt, Egija Zaura, Andrea Waters-Rist, Menno Hoogland, Domingo C. Salazar-Garcia, Mark Aldenderfer, Camilla Speller, Jessica Hendy, Darlene A. Weston, Sandy J. Macdonald, Gavin H. Thomas, Matthew J. Collins, Cecil M. Lewis Jr., Corinne Hofman, Christina Warinner
Andrew Ozga
To date, characterization of ancient oral (dental calculus) and gut (coprolite) microbiota has been primarily accomplished through a metataxonomic approach involving targeted amplification of one or more variable regions in the 16S rRNA gene. Specifically, the V3 region (E. coli341–534) of this gene has been suggested as an excellent candidate for ancient DNA amplification and microbial community reconstruction. However, in practice this metataxonomic approach often produces highly skewed taxonomic frequency data. In this study, we use non-targeted (shotgun metagenomics) sequencing methods to better understand skewed microbial profiles observed in four ancient dental calculus specimens previously analyzed by amplicon …
Mine Reclamation Using Biofuel Crops: Insights Into The Microbial Ecology Of The Switchgrass (Panicum Virgatum) Microbiome, Brianna L. Mayfield
Mine Reclamation Using Biofuel Crops: Insights Into The Microbial Ecology Of The Switchgrass (Panicum Virgatum) Microbiome, Brianna L. Mayfield
Graduate Theses, Dissertations, and Problem Reports
Bioenergy crop production has steadily increased due to growing political support for renewable energy, thus initiating a demand to find alternative agricultural land. An innovative option is the use of marginal soils, such as reclaimed mine lands, to produce bioenergy crops. Switchgrass (Panicum virgatum) is a promising bioenergy crop that can be grown on marginal lands due to its robust growth in various soil types and climates. However, little is known regarding plant-microbe interactions among switchgrass systems within reclaimed mine lands. A study conducted in 2008 grew switchgrass on high- and low- quality reclaimed mine sites (Hampshire and …
Linking Microbial Community Structure And Ecosystem Functions In Acidic Soil From Pennsylvania, Usa, Madison T. James, Sophia T. Farrisi, Shreya Shah, Vishal Shah
Linking Microbial Community Structure And Ecosystem Functions In Acidic Soil From Pennsylvania, Usa, Madison T. James, Sophia T. Farrisi, Shreya Shah, Vishal Shah
Sustainability Research & Creative Activities Grants Reports
Microorganisms play a critical role in the structure and functioning of soil ecosystems. Within acidic soil across the northeastern United States and Canada, we have little understanding of the microbial diversity present and its relationship to the biochemical cycles. The current study is aimed at understanding the taxonomical and functional diversities in the acidic soil obtained from near various types of trees, how the diversities change as a function of depth, and the linkage between taxonomical and functional diversities. From eight sampling locations, soil samples were collected from three horizons (depths). The three depths were 0-10 cm (A), 11-25 cm …
Survey Of Microbial Urea Degrader Diversity In Two Freshwater Ecosystems: Lake Shenandoah And The Shenandoah River, Naomi E. Gilbert
Survey Of Microbial Urea Degrader Diversity In Two Freshwater Ecosystems: Lake Shenandoah And The Shenandoah River, Naomi E. Gilbert
Senior Honors Projects, 2010-2019
One of the primary drivers of cyanobacterial harmful algal blooms (cHABs) in freshwater systems is nutrient loading, particularly of nitrogen and phosphorus. There has been an increased focus on assessing the role of nitrogen (N) in freshwater lakes and rivers that suffer cHABs. Urea, a widely-used, N-rich fertilizer, is a source of interest due to its abundance in freshwater ecosystems, primarily caused by anthropogenic nutrient loading. While recent work has shown that cHAB population succession may favor the toxic cyanobacterium Microcystis in urea-rich waters, the diversity of the associated bacterial community capable of degrading urea has yet to be determined. …
The Microbial Ecology Of Bacterial Lignocellulosic Degradation In The Ocean, Hannah Laing Yee Woo
The Microbial Ecology Of Bacterial Lignocellulosic Degradation In The Ocean, Hannah Laing Yee Woo
Doctoral Dissertations
The overarching theme of my dissertation is to study the role of bacteria in lignocellulose degradation. In recent years, more research has investigated the biodegradability of lignocellulose for biofuel production. The components of the lignocellulosic plant cell wall are considered intrinsically recalcitrant due to their structure. However, we hypothesize that these components are not intrinsically recalcitrant but their biodegradation is contingent on the environmental conditions, particularly the bacterial diversity. We believe bacteria will become especially important in lignocellulose degradation in conditions that are unfavorable for white-rot fungi. Therefore, we investigated the potential for lignin degradation by bacteria in the ocean …
Soil Microbial Community Composition And Respiration Along An Experimental Precipitation Gradient In A Semiarid Steppe, Cancan Zhao, Yuan Miao, Chengde Yu, Lili Zhu, Feng Wang, Lin Jiang, Dafeng Hui, Shiqiang Wan
Soil Microbial Community Composition And Respiration Along An Experimental Precipitation Gradient In A Semiarid Steppe, Cancan Zhao, Yuan Miao, Chengde Yu, Lili Zhu, Feng Wang, Lin Jiang, Dafeng Hui, Shiqiang Wan
Biology Faculty Research
As a primary limiting factor in arid and semiarid regions, precipitation strongly influences soil microbial properties. However, the patterns and mechanisms of soil microbial responses to precipitation have not been well documented. In this study, changes in soil microorganisms along an experimental precipitation gradient with seven levels of precipitation manipulation (i.e., ambient precipitation as a control and ±20%, ±40% and ±60% of ambient precipitation) were explored in a semiarid temperate steppe in northern China. Soil microbial biomass carbon and respiration as well as the ratio of fungal to bacterial biomass varied along the experimental precipitation gradient and peaked under the …
Intrinsic Challenges In Ancient Microbiome Reconstruction Using 16s Rrna Gene Amplification, Kirsten Ziesemer, Allison Mann, Krithivasan Sankaranarayanan, Hannes Schroeder, Andrew T. Ozga, Bernd W. Brandt, Egija Zaura, Andrea Waters-Rist, Menno Hoogland, Domingo C. Salazar-Garcia, Mark Aldenderfer, Camilla Speller, Jessica Hendy, Darlene A. Weston, Sandy J. Macdonald, Gavin H. Thomas, Matthew J. Collins, Cecil M. Lewis Jr., Corinne Hofman, Christina Warinner
Intrinsic Challenges In Ancient Microbiome Reconstruction Using 16s Rrna Gene Amplification, Kirsten Ziesemer, Allison Mann, Krithivasan Sankaranarayanan, Hannes Schroeder, Andrew T. Ozga, Bernd W. Brandt, Egija Zaura, Andrea Waters-Rist, Menno Hoogland, Domingo C. Salazar-Garcia, Mark Aldenderfer, Camilla Speller, Jessica Hendy, Darlene A. Weston, Sandy J. Macdonald, Gavin H. Thomas, Matthew J. Collins, Cecil M. Lewis Jr., Corinne Hofman, Christina Warinner
Biology Faculty Articles
To date, characterization of ancient oral (dental calculus) and gut (coprolite) microbiota has been primarily accomplished through a metataxonomic approach involving targeted amplification of one or more variable regions in the 16S rRNA gene. Specifically, the V3 region (E. coli341–534) of this gene has been suggested as an excellent candidate for ancient DNA amplification and microbial community reconstruction. However, in practice this metataxonomic approach often produces highly skewed taxonomic frequency data. In this study, we use non-targeted (shotgun metagenomics) sequencing methods to better understand skewed microbial profiles observed in four ancient dental calculus specimens previously analyzed by amplicon …
The Shellfish Corner -- Vibrios And Shellfish, Michael Rice
The Shellfish Corner -- Vibrios And Shellfish, Michael Rice
Michael A Rice
Pathogenic Vibrios are becoming an increasing problem for shellfish producers in North America and elsewhere. This paper reviews current research into the pathogenic nature of Vibrios and provides some practical advice for avoiding the propagation of Vibrios on shellfish farms nd in wild harvest molluscan shellfish.
Systems Biology Of Microcystis Blooms, Morgan Michelle Steffen
Systems Biology Of Microcystis Blooms, Morgan Michelle Steffen
Doctoral Dissertations
Cyanobacterial harmful algal blooms (cHABs) degrade freshwater lakes worldwide. Accumulation of nuisance biomass and production of noxious secondary metabolites can result in an expansive impact on both lake ecology and the surrounding communities. The cHAB forming organism Microcystis aeruginosa is known to produce the toxin microcystin, a compound nicknamed “fast death factor,” which has been implicated in animal poisonings and human liver failure and cancers. M. aeruginosa inhabits a wide range of freshwater lakes around the world, such as Lake Erie (USA/Canada) and Lake Tai (Taihu, China), and is often a dominant member of bloom communities. Such systems are well-studied …
The Pleiotropic Effects Of Beneficial Mutations Of Adapted Escherichia Coli Populations, Brian Scott Van Dam
The Pleiotropic Effects Of Beneficial Mutations Of Adapted Escherichia Coli Populations, Brian Scott Van Dam
Honors Theses and Capstones
Mutations that improve fitness in one environment can often be beneficial, deleterious, or neutral in alternative environments. When a single mutation effects fitness in multiple environments, it is said to be a pleiotropic, which can have important consequences for niche specialization, niche expansion, speciation, and even extinction in the face of environmental change. While previous studies have revealed that pleiotropy is nearly universal, the role of adaptive history in the spectrum of pleiotropic effects has yet to undergo detailed experimental observation. Using experimental evolution we gathered beneficial mutations in a previously adapted strain of Escherichia coli growing in the same …
Bacterially-Mediated Formation Of Rock Coatings In Kärkevagge, Swedish Lapland: A Mineralogical And Micro-Environmental Analog For Mars, Cassandra L. Marnocha
Bacterially-Mediated Formation Of Rock Coatings In Kärkevagge, Swedish Lapland: A Mineralogical And Micro-Environmental Analog For Mars, Cassandra L. Marnocha
Graduate Theses and Dissertations
The search for past or present life on Mars is, for now, limited to surface environments. An often neglected surface environment that could have served as an abode for life and could presently preserve evidence of that life is that of rock coatings. Rock coatings are mineral accretions on rock surfaces. On Earth, they are widespread and occur with considerable chemical diversity. There is growing evidence for a biotic role in their formation on Earth, particularly with respect to rock varnish. As a result, rock varnish has become a target of astrobiological interest on Mars, where varnish-like coatings have been …
Enzymes As Feed Additive To Aid In Responses Against Eimeria Species In Coccidia-Vaccinated Broilers Fed Corn-Soybean Meal Diets With Different Protein Levels, J. Parker, E. O. Oviedo Rondon, Beatrice A. Clack, S. Clemente-Hernandez, J. Osborne, J. C. Remus, H. Kettunen, H. Makivuokko, E. M. Pierson
Enzymes As Feed Additive To Aid In Responses Against Eimeria Species In Coccidia-Vaccinated Broilers Fed Corn-Soybean Meal Diets With Different Protein Levels, J. Parker, E. O. Oviedo Rondon, Beatrice A. Clack, S. Clemente-Hernandez, J. Osborne, J. C. Remus, H. Kettunen, H. Makivuokko, E. M. Pierson
Faculty Publications
This research aimed to evaluate the effects of adding a combination of exogenous enzymes to starter diets varying in protein content and fed to broilers vaccinated at day of hatch with live oocysts and then challenged with mixed Eimeria spp. Five hundred four 1-d-old male Cobb-500 chickens were distributed in 72 cages. The design consisted of 12 treatments. Three anticoccidial control programs [ionophore (IO), coccidian vaccine (COV), and coccidia-vaccine + enzymes (COV + EC)] were evaluated under 3 CP levels (19, 21, and 23%), and 3 unmedicated-uninfected (UU) negative controls were included for each one of the protein levels. All …
Effects Of Feed Additives And Mixed Eimeria Species Infection On Intestinal Microbial Ecology Of Broilers, M. E. Hume, S. Clemente-Hernandez, E. O. Oviedo Rondon
Effects Of Feed Additives And Mixed Eimeria Species Infection On Intestinal Microbial Ecology Of Broilers, M. E. Hume, S. Clemente-Hernandez, E. O. Oviedo Rondon
Faculty Publications
Evaluation of digestive microbial ecology is necessary to understand effects of growth-promoting feed. In the current study, the dynamics of intestinal microbial communities (MC) were examined in broilers fed diets supplemented with a combination of antibiotic (bacitracin methylene disalicylate) and ionophore (Coban 60), and diets containing 1 of 2 essential oil (EO) blends, Crina Poultry (CP) and Crina Alternate (CA). Five treatments were analyzed: 1) unmedicated uninfected control; 2) unmedicated infected control; 3) feed additives monensin (bacitracin methylene disalicylate) + monensin (Coban 60; AI); 4) EO blend CP; and 5) EO blend CA. Additives were mixed into a basal feed …
Characterization Of Microbial Activity, Mark P. Buttner, Patricia Cruz, Klaus J. Stetzenbach, Abe Van Luik, Thomas Williams, Amy J. Smiecinski
Characterization Of Microbial Activity, Mark P. Buttner, Patricia Cruz, Klaus J. Stetzenbach, Abe Van Luik, Thomas Williams, Amy J. Smiecinski
Publications (YM)
The overall goal of this study is to investigate the phenomena that affect the fate and transport of radionuclides in the environment. The objective of this task, “Characterization of Microbial Activity”, is to develop a molecular biological method for the characterization of the microbial population indigenous to the Yucca Mountain Project site, with emphasis in detection and measurement of species or groups of microorganisms that could be involved in actinide and/or metal reduction, and subsurface transport. Subtasks consist of QA planning and preparation, and literature review. This task is part of a cooperative agreement between the UNLV Research Foundation and …
Microbial Endemism And Biogeography, Brian P. Hedlund, James T. Staley
Microbial Endemism And Biogeography, Brian P. Hedlund, James T. Staley
Life Sciences Faculty Research
The topic of microbial biogeography is almost 100 years old, however, when confronted with questions about the existence and extent of endemism in the microbial world, many microbiologists respond with opinions and theoretical arguments rather than examples of well-conducted studies. We begin this chapter with an overview of this debate as it applies to free-living prokayotes in part because there are relatively few good microbial biogeography studies. Furthermore, the arguments help to frame microbial biogeography in the larger context of biodiversity in that if endemism is common, then many more species exist.