Medicine and Health Sciences Commons^™

Parasite Dynamics In Untreated Horses Through One Calendar Year, Ashley E. Steuer, Haley P. Anderson, Taylor Shepherd, Morgan Clark, Jessica A. Scare, Holli S. Gravatte, Martin K. Nielsen

Veterinary Science Faculty Publications

BACKGROUND: Horses are host to a plethora of parasites. Knowledge of the seasonality of parasite egg shedding and transmission is important for constructing parasite control programs. However, studies describing these patterns are sparse, and have largely been conducted only in the United Kingdom. This study evaluated strongylid egg shedding patterns and transmission dynamics of Strongylus vulgaris in naturally infected and untreated mares and foals through one calendar year in Kentucky, USA. The study also investigated the existence of a peri-parturient rise (PPR) in strongylid egg counts in foaling mares and collected information about Strongyloides westeri and Parascaris spp. in the …

Equine Arteritis Virus Long-Term Persistence Is Orchestrated By Cd8+ T Lymphocyte Transcription Factors, Inhibitory Receptors, And The Cxcl16/Cxcr6 Axis, Mariano Carossino, Pouya Dini, Theodore S. Kalbfleisch, Alan T. Loynachan, Igor F. Canisso, R. Frank Cook, Peter J. Timoney, Udeni B. R. Balasuriya

Veterinary Science Faculty Publications

Equine arteritis virus (EAV) has the unique ability to establish long-term persistent infection in the reproductive tract of stallions and be sexually transmitted. Previous studies showed that long-term persistent infection is associated with a specific allele of the CXCL16 gene (CXCL16S) and that persistence is maintained despite the presence of local inflammatory and humoral and mucosal antibody responses. Here, we performed transcriptomic analysis of the ampullae, the primary site of EAV persistence in long-term EAV carrier stallions, to understand the molecular signatures of viral persistence. We demonstrated that the local CD8⁺ T lymphocyte response is predominantly orchestrated …

Development And Evaluation Of A One-Step Multiplex Real-Time Taqman® Rt-Qpcr Assay For The Detection And Genotyping Of Equine G3 And G14 Rotaviruses In Fecal Samples, Mariano Carossino, Maria E. Barrandeguy, Erdal Erol, Yanqiu Li, Udeni B. R. Balasuriya

Veterinary Science Faculty Publications

Background: Equine rotavirus A (ERVA) is the leading cause of diarrhea in neonatal foals and has a negative impact on equine breeding enterprises worldwide. Among ERVA strains infecting foals, the genotypes G3P[12] and G14P[12] are the most prevalent, while infections by strains with other genomic arrangements are infrequent. The identification of circulating strains of ERVA is critical for diagnostic and surveillance purposes, as well as to understand their molecular epidemiology. Current genotyping methods available for ERVA and rotaviruses affecting other animal species rely on Sanger sequencing and are significantly time-consuming, costly and labor intensive. Here, we developed the first one-step …

Lipidomic Analysis Of Immune Activation In Equine Leptospirosis And Leptospira-Vaccinated Horses, Paul L. Wood, Margaret Steinman, Erdal Erol, Craig Carter, Undine Christmann, Ashutosh Verma

Veterinary Diagnostic Laboratory Faculty Publications

Currently available diagnostic assays for leptospirosis cannot differentiate vaccine from infection serum antibody. Several leptospiral proteins that are upregulated during infection have been described, but their utility as a diagnostic marker is still unclear. In this study, we undertook a lipidomics approach to determine if there are any differences in the serum lipid profiles of horses naturally infected with pathogenic Leptospira spp. and horses vaccinated against a commercially available bacterin. Utilizing a high-resolution mass spectrometry serum lipidomics analytical platform, we demonstrate that cyclic phosphatidic acids, diacylglycerols, and hydroperoxide oxidation products of choline plasmalogens are elevated in the serum of naturally …

An Epidemiologic Study Of Antimicrobial Resistance Of Staphylococcus Species Isolated From Equine Samples Submitted To A Diagnostic Laboratory, Ronita Adams, Jackie Smith, Stephan Locke, Erica Phillips, Erdal Erol, Craig N. Carter, Agricola Odoi

Veterinary Science Faculty Publications

Background

Antimicrobial resistance limits traditional treatment options and increases costs. It is therefore important to estimate the magnitude of the problem so as to provide empirical data to guide control efforts. The aim of this study was to investigate the burden and patterns of antimicrobial resistance (AMR) among equine Staphylococcus samples submitted to the University of Kentucky Veterinary Diagnostic Laboratory (UKVDL) from 1993 to 2009. Retrospective data of 1711 equine Staphylococcus samples submitted to the UKVDL during the time period 1993 to 2009 were included in the study. Antimicrobial susceptibility testing, that included 16 drugs, were performed using cultures followed …

Equine Arteritis Virus Elicits A Mucosal Antibody Response In The Reproductive Tract Of Persistently Infected Stallions, Mariano Carossino, Bettina Wagner, Alan T. Loynachan, R. Frank Cook, Igor F. Canisso, Lakshman Chelvarajan, Casey L. Edwards, Bora Nam, John F. Timoney, Peter J. Timoney, Udeni B. R. Balasuriya

Maxwell H. Gluck Equine Research Center Faculty Publications

Equine arteritis virus (EAV) has the ability to establish persistent infection in the reproductive tract of the stallion (carrier) and is continuously shed in its semen. We have recently demonstrated that EAV persists within stromal cells and a subset of lymphocytes in the stallion accessory sex glands in the presence of a significant local inflammatory response. In the present study, we demonstrated that EAV elicits a mucosal antibody response in the reproductive tract during persistent infection with homing of plasma cells into accessory sex glands. The EAV-specific immunoglobulin isotypes in seminal plasma included IgA, IgG1, IgG3/5, and IgG4/7. Interestingly, seminal …

A Serosurvey Of Selected Cystogenic Coccidia In Spanish Equids: First Detection Of Anti-Besnoitia Spp. Specific Antibodies In Europe, Daniel Gutiérrez-Expósito, Ignacio García-Bocanegra, Daniel K. Howe, Antonio Arenas-Montes, Michelle R. Yeargan, Sallyanne L. Ness, Luis M Ortega-Mora, G. Álvarez-García

Veterinary Science Faculty Publications

Background: Equine besnoitiosis, caused by Besnoitia bennetti, and equine protozoal myeloencephalitis (EPM), caused by Sarcocystis neurona and Neospora hughesi are relevant equine diseases in the Americas that have been scarcely studied in Europe. Thus, a serosurvey of these cystogenic coccidia was carried out in Southern Spain. A cross-sectional study was performed and serum samples from horses (n = 553), donkeys (n = 85) and mules (n = 83) were included. An in-house enzyme-linked immunosorbent assay (ELISA) was employed to identify a Besnoitia spp. infection and positive results were confirmed by an a posteriori western blot. For Neospora …

Allelic Variation In Cxcl16 Determines Cd3+ T Lymphocyte Susceptibility To Equine Arteritis Virus Infection And Establishment Of Long-Term Carrier State In The Stallion, Sanjay Sarkar, Ernest Bailey, Yun Young Go, R. Frank Cook, Ted Kalbfleisch, John E. Eberth, R. Lakshman Chelvarajan, Kathleen M. Shuck, Sergey Artiushin, Peter J. Timoney, Udeni B. R. Balasuriya

Maxwell H. Gluck Equine Research Center Faculty Publications

Equine arteritis virus (EAV) is the causative agent of equine viral arteritis (EVA), a respiratory, systemic, and reproductive disease of horses and other equid species. Following natural infection, 10–70% of the infected stallions can become persistently infected and continue to shed EAV in their semen for periods ranging from several months to life. Recently, we reported that some stallions possess a subpopulation(s) of CD3⁺ T lymphocytes that are susceptible to in vitro EAV infection and that this phenotypic trait is associated with long-term carrier status following exposure to the virus. In contrast, stallions not possessing the CD3⁺ T …

Equine Arteritis Virus Uses Equine Cxcl16 As An Entry Receptor, Sanjay Sarkar, Lakshman Chelvarajan, Yun Young Go, Frank Cook, Sergey Artiushin, Shankar Mondal, Kelsi Anderson, John E. Eberth, Peter J. Timoney, Theodore S. Kalbfleisch, Ernest F. Bailey, Udeni B. R. Balasuriya

Veterinary Science Faculty Publications

Previous studies in our laboratory have identified equine CXCL16 (EqCXCL16) to be a candidate molecule and possible cell entry receptor for equine arteritis virus (EAV). In horses, the CXCL16 gene is located on equine chromosome 11 (ECA11) and encodes a glycosylated, type I transmembrane protein with 247 amino acids. Stable transfection of HEK-293T cells with plasmid DNA carrying EqCXCL16 (HEK-EqCXCL16 cells) increased the proportion of the cell population permissive to EAV infection from < 3% to almost 100%. The increase in permissiveness was blocked either by transfection of HEK-EqCXCL16 cells with small interfering RNAs (siRNAs) directed against EqCXCL16 or by pretreatment with guinea pig polyclonal antibody against EqCXCL16 protein (Gp anti-EqCXCL16 pAb). Furthermore, using a virus overlay protein-binding assay (VOPBA) in combination with far-Western blotting, gradient-purified EAV particles were shown to bind directly to the EqCXCL16 protein in vitro. The binding of biotinylated virulent EAV strain Bucyrus at 4°C was significantly higher in HEK-EqCXCL16 cells than nontransfected HEK-293T cells. Finally, the results demonstrated …

Equine Protozoal Myeloencephalitis: An Updated Consensus Statement With A Focus On Parasite Biology, Diagnosis, Treatment, And Prevention, S. M. Reed, M. Furr, Daniel K. Howe, A. L. Johnson, R. J. Mackay, J. K. Morrow, N. Pusterla, S. Witonsky

Veterinary Science Faculty Publications

Equine protozoal myeloencephalitis (EPM) remains an important neurologic disease of horses. There are no pathognomonic clinical signs for the disease. Affected horses can have focal or multifocal central nervous system (CNS) disease. EPM can be difficult to diagnose antemortem. It is caused by either of 2 parasites, Sarcocystis neurona and Neospora hughesi, with much less known about N. hughesi. Although risk factors such as transport stress and breed and age correlations have been identified, biologic factors such as genetic predispositions of individual animals, and parasite-specific factors such as strain differences in virulence, remain largely undetermined. This consensus statement …

The Distribution Pattern Of Halicephalobus Gingivalis In A Horse Is Suggestive Of A Haematogenous Spread Of The Nematode, Christina Henneke, Anna Jespersen, Stine Jacobsen, Martin K. Nielsen, Fintan Mcevoy, Henrik E. Jensen

Veterinary Science Faculty Publications

The majority of Halicephalobus gingivalis-infections in horses have been fatal and are usually not diagnosed before necropsy. Therefore, knowledge about the nematode and the pathogenesis of infection in horses is limited. This has resulted in an on-going discussion about the port of entry and subsequent dissemination of H. gingivalis within the host. The present case of H. gingivalis-infection in a horse was diagnosed ante mortem. Post mortem findings, the distribution pattern of H. gingivalis nematodes in the brain, a high prevalence of inflammation in close relation to blood vessels, and the presence of the nematode in multiple organs …

Svsxp: A Strongylus Vulgaris Antigen With Potential For Prepatent Diagnosis, Ulla V. Andersen, Daniel K. Howe, Sriveny Dangoudoubiyam, Nils Toft, Craig R. Reinemeyer, Eugene T. Lyons, Susanne N. Olsen, Jesper Monrad, Peter Nejsum, Martin K. Nielsen

Veterinary Science Faculty Publications

BACKGROUND: Strongyle parasites are ubiquitous in grazing horses. Strongylus vulgaris, the most pathogenic of the large strongyles, is known for its extensive migration in the mesenteric arterial system. The lifecycle of S. vulgaris is characterised by a long prepatent period where the migrating larvae are virtually undetectable as there currently is no test available for diagnosing prepatent S. vulgaris infection. Presence of S. vulgaris larvae in the arterial system causes endarteritis and thrombosis with a risk of non-strangulating intestinal infarctions. Emergence of anthelmintic resistance among cyathostomins has led to recommendations of reduced treatment intensity by targeting horses that exceed a …

Inflammatory Responses To Induced Infectious Endometritis In Mares Resistant Or Susceptible To Persistent Endometritis, Mette Christoffersen, Elizabeth Woodward, Anders M. Bojesen, Stine Jacobsen, Morten R. Petersen, Mats H. T. Troedsson, Henrik Lehn-Jensen

Veterinary Science Faculty Publications

BACKGROUND: The objective of the study was to evaluate the gene expression of inflammatory cytokines (interleukin [IL]-1β, IL-6, IL-8, IL-10, tumor necrosis factor [TNF]-α, IL-1 receptor antagonist [ra] and serum amyloid A (SAA) in endometrial tissue and circulating leukocytes in response to uterine inoculation of 105 colony forming units (CFU) Escherichia coli in mares. Before inoculation, mares were classified as resistant or susceptible to persistent endometritis based on their uterine inflammatory response to infusion of 109 killed spermatozoa and histological assessment of the endometrial quality. Endometrial biopsies were obtained 3, 12, 24 and 72 hours (h) after bacterial inoculation and …

Oas1 Polymorphisms Are Associated With Susceptibility To West Nile Encephalitis In Horses, Jonathan J. Rios, Joann G. W. Fleming, Uneeda K. Bryant, Craig N. Carter, John C. Huber Jr., Maureen T. Long, Thomas E. Spencer, David L. Adelson

Veterinary Diagnostic Laboratory Faculty Publications

West Nile virus, first identified within the United States in 1999, has since spread across the continental states and infected birds, humans and domestic animals, resulting in numerous deaths. Previous studies in mice identified the Oas1b gene, a member of the OAS/RNASEL innate immune system, as a determining factor for resistance to West Nile virus (WNV) infection. A recent case-control association study described mutations of human OAS1 associated with clinical susceptibility to WNV infection. Similar studies in horses, a particularly susceptible species, have been lacking, in part, because of the difficulty in collecting populations sufficiently homogenous in their infection and …

Whole-Genome Snp Association In The Horse: Identification Of A Deletion In Myosin Va Responsible For Lavender Foal Syndrome, Samantha A. Brooks, Nicole Gabreski, Donald Miller, Abra Brisbin, Helen E. Brown, Cassandra Streeter, Jason Mezey, Deborah Cook, Douglas F. Antczak

Veterinary Science Faculty Publications

Lavender Foal Syndrome (LFS) is a lethal inherited disease of horses with a suspected autosomal recessive mode of inheritance. LFS has been primarily diagnosed in a subgroup of the Arabian breed, the Egyptian Arabian horse. The condition is characterized by multiple neurological abnormalities and a dilute coat color. Candidate genes based on comparative phenotypes in mice and humans include the ras-associated protein RAB27a (RAB27A) and myosin Va (MYO5A). Here we report mapping of the locus responsible for LFS using a small set of 36 horses segregating for LFS. These horses were genotyped using a newly available single nucleotide polymorphism (SNP) …

The Mare Reproductive Loss Syndrome And The Eastern Tent Caterpillar: A Toxicokinetic/Statistical Analysis With Clinical, Epidemiologic, And Mechanistic Implications, Manu Sebastian, Marie G. Gantz, Thomas Tobin, J. Daniel Harkins, Jeffrey M. Bosken, Charlie Hughes, Lenn R. Harrison, William V. Bernard, Dana L. Richter, Terrence D. Fitzgerald

Maxwell H. Gluck Equine Research Center Faculty Publications

During 2001, central Kentucky experienced acute transient epidemics of early and late fetal losses, pericarditis, and unilateral endophthalmitis, collectively referred to as mare reproductive loss syndrome (MRLS). A toxicokinetic/statistical analysis of experimental and field MRLS data was conducted using accelerated failure time (AFT) analysis of abortions following administration of Eastern tent caterpillars (ETCs; 100 or 50 g/day or 100 g of irradiated caterpillars/day) to late-term pregnant mares. In addition, 2001 late-term fetal loss field data were used in the analysis. Experimental data were fitted by AFT analysis at a high (P < .0001) significance. Times to first abortion (“lag time”) and abortion rates were dose dependent. Lag times decreased and abortion rates increased exponentially with dose. Calculated dose × response data curves allow interpretation of abortion data in terms of “intubated ETC equivalents.” Analysis suggested that field exposure to ETCs in 2001 in central Kentucky commenced on approximately April 27, was initially equivalent to approximately 5 g of intubated ETCs/day, and increased to approximately 30 g/day at the outbreak peak. This analysis accounts for many aspects of the epidemiology, clinical presentations, and manifestations of MRLS. It allows quantitative interpretation of experimental and field MRLS data and has implications for the basic mechanisms underlying MRLS. The results support suggestions that MRLS is caused by exposure to or ingestion of ETCs. The results also show that high levels of ETC exposure produce intense, focused outbreaks of MRLS, closely linked in time and place to dispersing ETCs, as occurred in central Kentucky in 2001. With less intense exposure, lag time is longer and abortions tend to spread out over time and may occur out of phase with ETC exposure, obscuring both diagnosis of this syndrome and the role of the caterpillars.