Pathogenic Microbiology Commons^™

Ticks Elicit Variable Fibrinogenolytic Activities Upon Feeding On Hosts With Different Immune Backgrounds, Ashish Vora, Vikas Taank, John F. Anderson, Durland Fish, Daniel E. Sonenshine, John D. Catravas, Hameeda Sultana, Girish Neelakanta

Biological Sciences Faculty Publications

Ticks secrete several anti-hemostatic factors in their saliva to suppress the host innate and acquired immune defenses against infestations. Using Ixodes scapularis ticks and age-matched mice purchased from two independent commercial vendors with two different immune backgrounds as a model, we show that ticks fed on immunodeficient animals demonstrate decreased fibrinogenolytic activity in comparison to ticks fed on immunocompetent animals. Reduced levels of D-dimer (fibrin degradation product) were evident in ticks fed on immunodeficient animals in comparison to ticks fed on immunocompetent animals. Increased engorgement weights were noted for ticks fed on immunodeficient animals in comparison to ticks fed on …

First Evidence For A Vibrio Strain Pathogenic To Mytilus Edulis Altering Hemocyte Immune Capacities, Yosra Ben Cheikh

2nd International Conference of Fish & Shellfish Immunology

No abstract provided.

Implication Of Biological And Synthetic Nanoparticles In Evolution And Development Of Antibiotic Resistance Relevant For Aquaculture, Petter Langlete

2nd International Conference of Fish & Shellfish Immunology

No abstract provided.

Aeromonas Hydrophila In Amphibians: Harmless Bystander Or Opportunistic Pathogen, Zachary P. Rivas

Honors Undergraduate Theses

For several decades amphibian populations have been declining. Historically, the bacterium A. hydrophila (Ah) was hypothesized to be the causal factor in amphibian disease and population declines. However, with the discovery of a chytrid fungus, Batrachochytrium dendrobatidis (Bd) in 1998, which was identified on the skin of amphibians during documented mortality events, Ah research became of minor interest as focus shifted to Bd. Recent studies into the immunocompromising abilities of Bd, however, have opened new questions about its relationship with Ah and their combined effects on a host.

In this study, I explore the …

Phylogenetic Investigation Of Enteric Bovine Coronavirus In Ireland Reveals Partitioning Between European And Global Strains, Lynda Gunn, P. J. Collins, M. J. O'Connell, Helen O'Shea

Department of Biological Sciences Publications

Background

Bovine coronavirus is a primary cause of neonatal calf diarrhea worldwide, and is also associated with acute diarrhea in adult cattle during the winter season. There are no reports on molecular characterization of bovine coronavirus in Ireland, and little data exists apart from serological studies.

Findings

In this study, 11 neonatal (mean age 9 days) calf BCoV strains from the south of Ireland were collected over a one year period and characterized using molecular methods. The spike gene which encodes a protein involved in viral entry, infectivity and immune response shows the most variability amongst the isolates and was …

A Tail Of Two Phages: Genomic And Functional Analysis Of Listeria Monocytogenes Phages Vb_Lmos_188 And Vb_Lmos_293 Reveal The Receptor-Binding Proteins Involved In Host Specificity, Aidan Casey, Kieran Jordan, Horst Neve, Aidan Coffey, Olivia Mcauliffe

Department of Biological Sciences Publications

The physical characteristics of bacteriophages establish them as viable candidates for downstream development of pathogen detection assays and biocontrol measures. To utilize phages for such purposes, a detailed knowledge of their host interaction mechanisms is a prerequisite. There is currently a wealth of knowledge available concerning Gram-negative phage-host interaction, but little by comparison for Gram-positive phages and Listeria phages in particular. In this research, the lytic spectrum of two recently isolated Listeria monocytogenes phages (vB_LmoS_188 and vB_LmoS_293) was determined, and the genomic basis for their observed serotype 4b/4e host-specificity was investigated using comparative genomics. The late tail genes of these …

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.

Thermal Inactivation Of Shiga Toxin-Producing Escherichia Coli In Foods, Malcond David Valladares

Doctoral Dissertations

Emerging non-O157 Shiga toxin-producing Escherichia coli (STEC) were recently added to the zero tolerance policy by the USDA-FSIS. Therefore, the precise characterization of their thermal inactivation kinetics in different foods and the effect of stress on thermal inactivation are needed. This research aimed at determining the heat inactivation kinetics of non-O157 and O157 STECs in buffer and model food matrices and the effects of DnaK levels on thermal resistance after acid and heat-shock. Thermal inactivation was carried out in either in 2-ml glass vials or nylon vacuum-sealed bags for buffer and food (spinach, ground-beef, turkey deli-meat, pasta) samples, respectively. Vials …

The Shellfish Corner--Shellfish Sanitation And The Price Of Shellfish, Michael A. Rice

Michael A Rice

Prices of raw molluscan shellfish in different countries around the world are tied to perceived risk of becoming ill if consumed. Wholesale prices of oysters in the southern New England from 1880 to 2010 are analyzed in relation to introduction of flush toilets and sewer systems in the early 20th Century, the initiation of the US National Shellfish Sanitation Program in 1925 and renewed consumer interest in consuming raw shellfish in the latter half of the 20th Century.

Methane Production By A Packed-Bed Anaerobic Digester Fed Dairy Barn Flush Water, Sean Richard Thomson

Master's Theses

Packed-bed digesters are an alternative to covered lagoon digesters for methane production and anaerobic treatment of dilute wastewaters such as dairy barn flush water. The physical media of packed-beds retain biofilms, often allowing increased treatment rates. Previous studies have evaluated several types of media for digestion of dilute wastewaters, but cost and media fouling have setback commercial development. A major operational cost has been effluent recirculation pumping.

In the present effort, a novel approach to anaerobic digestion of flush dairy water was developed at pilot-scale: broken walnut shells were used as a low-cost packed-bed medium and effluent recirculation was replaced …

Characterization Of Corynebacterium Pseudotuberculosis Biovar Equi Isolates Obtained From Cal Poly Horses And Review Of Application Of Transposons To Better Prevent Pigeon Fever In Horses, Irene Hasen

Animal Science

No abstract provided.

Poultry Performance And Food Safety Impacts Of Selected Organic Acids And Probiotics, Anita Menconi

Graduate Theses and Dissertations

Improving production parameters and controlling foodborne pathogens have been challenges to the poultry industry. Salmonella has been the most common bacterial pathogen in laboratory confirmed foodborne illness cases, and contaminated poultry and poultry products have been identified as the most important source of transmission of Salmonella to humans. Therefore, research on effective interventions to reduce Salmonella transmission at the poultry production level has gained attention. Initially, a series of studies was conducted to evaluate the use of selected organic acids in controlling foodborne pathogens and improving poultry performance. Then, the characterization and application of lactic acid bacteria and Bacillus spp. …

Phages Of Non-Diary Lactococci: Isolation And Characterization Of Phi L47, A Phage Infecting The Grass Isolate Lactococcus Lactis Ssp Cremoris Dpc6860, Daniel Cavanagh, Caitríona M. Guinane, Horst Neve, Aidan Coffey, R. Paul Ross, Gerald F. Fitzgerald, Olivia Mcauliffe

Department of Biological Sciences Publications

Lactococci isolated from non-dairy sources have been found to possess enhanced metabolic activity when compared to dairy strains. These capabilities may be harnessed through the use of these strains as starter or adjunct cultures to produce more diverse flavor profiles in cheese and other dairy products. To understand the interactions between these organisms and the phages that infect them, a number of phages were isolated against lactococcal strains of non-dairy origin. One such phage, ΦL47, was isolated from a sewage sample using the grass isolate L. lactis ssp. cremoris DPC6860 as a host. Visualization of phage virions by transmission electron …

Coccidia Of Gerbils From Mongolia, Ethan T. Jensen

School of Biological Sciences: Dissertations, Theses, and Student Research

In this study, gerbils collected in the Mongolia over the summers of 2009-2012 were examined for coccidia. In total, 171 gerbils of three species from 22 localities were examined for coccidia. Coccidian oocysts were identified from 21 gerbils, but those found in 1 of those gerbils were probably pseudoparasites of the host from which they were recovered. From the remaining 20 gerbils, 7 morphotypes of Eimeria and 1 morphotype of Isospora were identified. Four of the 7 morphotypes of Eimeria were attributed to new species which were described in this study. In addition, 10 previously described species of Eimeria were …

Equine Serum Antibody Responses To Streptococcus Equi And Streptococcus Zooepidemicus, Rafaela De Negri

Theses and Dissertations--Veterinary Science

Streptococcus zooepidemicus (Sz) and Streptococcus equi (Se) share 98% DNA sequence homology, but display different pathogenic properties. Infection by one organism does not cross-protect against the other. To better understand pathogenic differences between these organisms and gain information about which proteins are expressed in horses infected experimentally with Se, intrauterine Sz or naturally with respiratory Sz we compared antibody specificities of convalescent sera using ELISA. These comparisons were based on sets of 8 and 14 immunoreactive recombinant proteins of Se strain CF32 and Sz strain NC78, respectively. Sera from donkeys that were previously naturally affected with strangles and later developed …

Seroprevalence Of Brucellosis In Livestock Within Three Endemic Regions Of The Country Of Georgia, Eliso Mamisashvili, Ian T. Kracalik, Tinatin Onashvili, Lela Kerdzevadze, Ketevan Goginashvili, Tamar Tigilauri, Marina Donduashvili, Marina Nikolaishvili, Irma Beradze, Marina Zakareishvili, Maka Kokhreidze, Makvala Gelashvili, Nino Vepkhvadze, S. Elizabeth Rácz, Philip H. Elzer, Mikeljon P. Nikolich, Jason K. Blackburn

Harold W. Manter Laboratory of Parasitology: Faculty and Staff Publications

Brucellosis is the one of most common livestock zoonoses in Georgia, resulting in significant economic losses. Livestock were sampled in three regions of Georgia (Kakheti, Kvemo Kartli, Imereti). Districts that historically reported high numbers of brucellosis related morbidity were selected for serological, bacteriological and molecular surveys. Surveying efforts yielded samples from 10,819 large and small ruminants. In total, 735 serological tests were positive on Rose Bengal and 33 bacterial isolates were recovered and identified as Brucella melitensis or Brucella abortus by microbiology and AMOS-PCR. A Bayesian framework was implemented to estimate the true prevalence of the disease given an imperfect …

Changes To The Equine Hindgut Microflora In Response To Antibiotic Challenge, Brittany E. Harlow

Theses and Dissertations--Animal and Food Sciences

Antibiotics are important to equine medicine, but can cause detrimental side-effects including reduced feed intake, allergic reactions, and diarrhea. Antibiotic-associated diarrhea (AAD) is attributed to disruption of the hindgut microflora, permitting proliferation of pathogenic microbes. The objectives were to evaluate the effects of antibiotics on beneficial fecal bacteria, AAD-associated pathogens, microbial species richness and fermentation. Horses were assigned to treatment groups: control (no antibiotics, n=6), trimethoprim-sulfadiazine (oral, n=6), or sodium ceftiofur (IM, n=6). Fecal samples were taken during adaptation (3 wk), antibiotic challenge (1 wk), and withdrawal (1 wk). Fecal cellulolytics decreased by >99% during challenge and did not recover …

Group Size And Nest Spacing Affect Buggy Creek Virus (Togaviridae: Alphavirus) Infection In Nestling House Sparrows, Valerie A. Brown, Charles R. Brown

Papers in Ornithology

The transmission of parasites and pathogens among vertebrates often depends on host population size, host species diversity, and the extent of crowding among potential hosts, but little is known about how these variables apply to most vector-borne pathogens such as the arboviruses (arthropod-borne viruses). Buggy Creek virus (BCRV; Togaviridae: Alphavirus) is an RNA arbovirus transmitted by the swallow bug (Oeciacus vicarius) to the cliff swallow (Petrochelidon pyrrhonota) and the introduced house sparrow (Passer domesticus) that has recently invaded swallow nesting colonies. The virus has little impact on cliff swallows, but house sparrows are seriously …

A Multidisciplinary Approach To Food Safety Evaluation: Hummus Spoilage And Microbial Analysis Of Kitchen Surfaces In Residential Child Care Institutions (Rcci) In Massachusetts, U.S.A., Elsina E. Hagan

Masters Theses 1911 - February 2014

Food borne illnesses continues to be a public health challenge in the United States (U.S.); an estimated 9.4 million incident cases occurred in 2011. In view of this challenge we conducted two food safety studies; 1) related to product formulation (hummus spoilage challenge study) and 2) evaluating the microbial safety of domestic kitchen surfaces in Residential Child Care Institutions (RCCI pilot study).

Hummus is of Mediterranean origin but is currently eaten globally. This challenge study evaluates a variety of industrial hummus formulations (four in total, differing in pH and/or addition of a preservative (natamycin). Two batches were setup: batch 1; …

Communities Of Cloacal Bacteria In Tree Swallow Families, Michael Lombardo, Patrick Thorpe, R. Cichewicz, M. Henshaw, C. Millard, C. Steen, T. Zeller

Michael P Lombardo

Our aim in this study was to survey the communities of bacteria found in the cloacae of adult and nestling Tree Swallows (Tachycineta bicolor), determine if there were familial patterns of prevalence, and determine if there were relationships between bacteria loads and nestling size when 12 days old and fledging success.

On The Evolution Of Sexually Transmitted Diseases In Birds, Michael Lombardo

Michael P Lombardo

"The definitive version is available at www.blackwell-synergy.com".

Sexually transmitted diseases (STDs) in animals are caused by pathogens that are transmitted during copulation. Birds have played an important role in the development of STD-centered theories of mating behavior. However, it is not known whether STDs exist in wild bird populations. While the avian cloaca with its dual functions of gamete transfer and excretion seemingly predisposes birds for the evolution of STDs, the life history patterns of most birds (i.e., seasonal breeders with relatively brief annual periods of sexual activity) suggest otherwise. The importance of STDs as selective forces that shape host …

Effects Of The Pathogenic Water Mold Saprolegnia Ferax On Survival Of Amphibian Larvae, John M. Romansic, Kristin A. Diez, Elise M. Higashi, James E. Johnson, Andrew R. Blaustein

All Faculty Scholarship for the College of the Sciences

Infectious diseases are a significant threat to worldwide biodiversity. Amphibian declines, a significant part of current biodiversity losses, are in many cases associated with infectious disease. Water molds are one group of pathogens affecting amphibians on a worldwide basis. Although water molds have been studied extensively for their effects on host embryos, little information is available about how they affect post-embryonic amphibians. We tested the effects of one species of water mold, Saprolegnia ferax, in a comparative study of larvae of 4 amphibian species: Pseudacris regilla (Pacific treefrog), Rana cascadae (Cascades frog), Ambystoma macrodactylum (long-toed salamander), and R. aurora (red-legged …

Letter From The Dean, Lalit Verma

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

No abstract provided.

Host And Seasonal Effects On The Infection Dynamics Of Skrjabinoptera Phrynosoma (Ortlepp) Schulz, 1927, A Parasitic Nematode Of Horned Lizards, Kathryn Claire Hilsinger

Electronic Theses and Dissertations

Author's Abstract: Skrjabinoptera phrynosoma (Ortlepp) Schulz, 1927 is a common parasitic nematode of horned lizards. The life cycle of S. phrynosoma was described by Lee in 1957, but has received little attention since. The present study addressed effect of season as well as host characteristics on the infection dynamics in lizard hosts. In the Alvord Basin in southeastern Oregon, S. phrynosoma were collected from Phrynosoma platyrhinos Gerard 1852 horned lizards via stomach flushes, cloaca flushes and fecal pellet collections. Parasite load variables (number of nematodes per host, length of those nematodes, and total worm burden (ΣL)) were analyzed within three …

Antimicrobial Activity Screening Of Recombinant And Synthetic Varasin A Defensin From The Hard Tick Dermacentor Variabilis Against Various Bacteria, Julia A. Sharp

Biological Sciences Theses & Dissertations

Hematophagous arthropods, such as ticks and mosquitoes, rely on their innate immune system for defense against pathogens ingested in a blood meal as well as those acquired through injury. In response to pathogen recognition, the production of antimicrobial peptides, such as defensin, is typically upregulated. Varisin, a defensin, is thought to be a key component in the immunocompetence of the hard tick D. variabilis against Borrelia burgdorferi, the causative agent of Lyme disease. To study the antimicrobial effects of varisin, recombinant varisin was expressed by both insect cells and E coli. Purification of the protein followed by enterokinase treatment yielded …

Defensin Transcript Distribution In Tissues And Life Stages Of The Ixodid Ticks Amblyomma Americanum And Ixodes Scapularis, Stephanie M. Todd

Biological Sciences Theses & Dissertations

A number of bacterial, viral, and protozoan diseases are transmitted to humans via arthropods. Arthropods possess an innate immune system to destroy invading microorganisms. However, arthropods unable to rid their systems of pathogens function as disease vectors. The American dog tick, Dermacentor variabilis, destroys invading Borrelia burgdorferi spirochetes, preventing transmission. In contrast, the black-legged tick, Ixodes scapularis, which is unable to destroy acquired B. burgdorferi, successfully vectors the pathogen. The Lone Star tick, Amblyomma americanum, vectors a similar pathogen called Borrelia lonestari. The distribution of defensin, an antimicrobial peptide of the innate immune system, was examined in A. americanum and/. …

The Defensin Gene In Dermacentor Variabilis And Ixodes Scapularis, Katherine Corbett Seguin

Biological Sciences Theses & Dissertations

In response to microbial challenge, invertebrates rely on their innate immune response to recognize and destroy harmful pathogens. One of the primary proteins produced by the response and that has been observed in many invertebrates, including insects, mussels, and ticks, is defensin. These proteins are responsible for forming pores in the membranes of invading microbes thereby destroying them. This study examined the gene coding region for defensin in two important tick disease vectors, Dermacentor variabilis and Ixodes scapularis. PCR amplification of the genes from tick chromosomal DNA resulted in the amplification of a 225 base pair amplicon. Sequencing of …

Communities Of Cloacal Bacteria In Tree Swallow Families, Michael P. Lombardo, Patrick A. Thorpe, R. Cichewicz, M. Henshaw, C. Millard, C. Steen, T. K. Zeller

Peer Reviewed Publications

Our aim in this study was to survey the communities of bacteria found in the cloacae of adult and nestling Tree Swallows (Tachycineta bicolor), determine if there were familial patterns of prevalence, and determine if there were relationships between bacteria loads and nestling size when 12 days old and fledging success.

Lupinosis, M R. Gardiner

Journal of the Department of Agriculture, Western Australia, Series 4

In spite of many years of intensive investigation lupinosis remains a remarkably complex and baffling problem. Current research is throwing new light on the disease and it is now much better understood— although far from beaten.

Lupinosis research is co-ordinated by the Department of Agriculture's Lupinosis Committee, on which are represented all groups working on the disease. These include veterinary surgeons and pathologists, chemists, plant pathologists and animal husbandry specialists.

Chairman of the Committee is Dr M. R. Gardiner, Chief of the Department's Animal Division and a veteran of lupinosis research.

In this article Dr Gardiner summarises the current state …

A Survey Of The Incidence Of Salmonellosis In Three Groups Of Wild Animals, James T. Heiberger

Masters Theses

No abstract provided.