Disease diagnosis in horses involves the identification and characterization of illnesses through various diagnostic methods and tools. This process is essential for effective veterinary care and management of equine health. Techniques used in diagnosing diseases in horses include clinical examinations, laboratory tests, imaging modalities such as ultrasonography and radiography, and molecular diagnostics. Blood tests are frequently utilized to assess parameters such as complete blood count and biochemical profiles, which can indicate underlying health issues. Additionally, advancements in genetic testing and biomarker identification have enhanced the ability to detect specific diseases early. This page aggregates peer-reviewed research studies and scholarly articles that explore diagnostic methodologies, their applications, and their impact on equine health management.
Ellero N, Maggi A, Busoni V, Imposimato I, Castagnetti C, Lanci A, Mariella J, Freccero F.This study aimed to develop a standardized ultrasound (US) protocol using selected thoracic and abdominal acoustic windows, to assess its feasibility and applicability in healthy foals, and to evaluate its usefulness for detecting common thoracic and abdominal conditions in sick foals. The Focused US (FUS) protocol included 12 thoraco-abdominal windows (4 right-side, 3 ventral, 5 left-side) using a curved-array probe. It was applied to cohorts of healthy (n = 17) and sick (n = 23) foals by a veterinary clinician with limited US experience. The FUS showed good feasibility and applicabil...
Decoster C, Lefère L, Raes E, van Loon G, Dufourni A.Leptospirosis is a widespread zoonotic, infectious disease associated with abortion, stillbirth, as well as liver and kidney failure. Leptospiral Pulmonary Haemorrhage Syndrome (LPHS) has increasingly been reported in human and canine patients infected by Leptospira and is associated with a high fatality rate. In equine medicine, pulmonary haemorrhage has mainly been described in foals with leptospiral infections, but rarely in adult horses. Objective: To characterise the clinicopathological features of pulmonary haemorrhage as a distinct disease entity in adult horses with leptospirosis, term...
Jager MC, Luethy D, Shallop S, Cathcart J, Divers TJ, Tan JY, Beasley EM, Johnson P, Leduc L, Smith C, Jamieson CA, Magdesian KG, Van de Walle GR....Equine hepacivirus (EqHV) is closely related to hepatitis C virus (HCV), which causes persistent infection and chronic hepatitis in people. Information on persistent EqHV infection and hepatitis is limited. Objective: To report 19 cases of chronic hepatitis and persistent EqHV infection. Methods: Mixed retrospective and prospective case series. Methods: Inclusion criteria were: (1) chronic hepatitis, defined as persistently increased serum liver biomarkers, increased serum liver biomarkers accompanied by histopathological evidence of chronicity, for example, fibrosis, or both; (2) positive ser...
Ketphan W, Sato M, Tsujimura K, Mizutani T, Takemae H.Equine rhinitis B virus (ERBV), a member of the Picornaviridae family, is associated with mild to moderate respiratory illness in horses, yet its genomic diversity remains incompletely characterized. In this study, we performed metagenomic analysis on a rectal swab sample from a diarrheic foal confirmed to be positive for rotavirus A. Unexpectedly, we identified a highly divergent ERBV strain with a 9,448-nucleotide genome encoding a 2,721-amino-acid polyprotein. Sequence analysis revealed only 62.5-63.1% identity in the polyprotein and 47.1-49.8% in the VP1 region compared to known ERBV serot...
Girisgin O, Gülegen E, Girisgin AO, Cirak VY.Anoplocephalid species are responsible for causing tapeworm infection in horses. The disease may cause serious health issues, including discomfort, colic, and even intestinal perforation and death. A study was carried out to compare the detection rates of tapeworm eggs in naturally infected horses using two different examination solutions. For this purpose, faecal samples of 241 horses were examined with a combined sedimentation + centrifugation + flotation technique using saturated sugar solution (specific gravity (SG) = 1.30) as the basis and potassium carbonate (KCO) solution (S...
Pourmahdi Borujeni M, Ghobadian Diali H, Mashhadi AG, Aliabad MJ.The recent identification of novel viruses associated with hepatitis in horses has prompted equine veterinarians to investigate the viral factors contributing to equine hepatitis. Hepacivirus equi (EqHV), a member of the Flaviviridae family within the Hepacivirus genus, has been detected in horses affected by hepatitis. Globally, EqHV is highly conserved, existing as a single genotype with three distinct subtypes (Subtypes 1-3). Numerous studies have detected the virus by PCR and identified EqHV-specific antibodies through serological tests in different regions worldwide. However, to the best ...
Kamiński S, Bejda J, Lewczuk D.The method for identifying the causative mutation for Warmblood Fragile Foal Syndrome (WFFS) involved PCR amplification of a 259-base pair fragment of the PLOD1 gene and its digestion with the restriction enzyme Aci I was developed, allowing for the clear detection of WFFS carriers. Eight WFFS carriers were detected among 308 warmblood horses kept in different farms across Poland, giving an overall frequency of 2.59%, which indicates a rather low frequency of the causative mutation for WFFS in Poland. Further research should be conducted on a larger number of horses, particularly those breeds ...
Guadalupi M, Girelli CR, Della Tommasa S, Corte FD, Crovace AM, Fanizzi FP, Brehm W, Lacitignola L.Joint and tendon sheath diseases are a major cause of lameness and reduced performance in horses. Synovial fluid composition changes in response to pathological processes and metabolomic profiling offers a promising approach to detect these alterations. While equine joint metabolomics has been explored, little is known about the metabolomic profile of tendon sheaths. This study aimed to characterize and compare the synovial fluid metabolomic profiles of healthy and pathological joints and tendon sheaths in horses using high-resolution H Nuclear Magnetic Resonance spectroscopy, and to identify ...
Hiblu MA, Ahmed MO.This case report documents the first identified Brucella infection in a 6-year-old male Thoroughbred horse in Libya. The horse exhibited muscle and joint pain, inflammation over the shoulders with a pulpy texture (fistulous withers), stress, fatigue, and potential systemic infection. Its diagnosis was confirmed through serological testing, with agglutination titers of 1/80 for B. melitensis and 1/160 for B. abortus, and a blood culture revealing Gram-negative coccobacilli. After 3 weeks of combination therapy with rifampicin and doxycycline, the inflammation resolved, systemic signs disappeare...
Underberg BA, Van der Vekens E, Drews B, Kaessmeyer S.Equine laminitis is a complex and potentially fatal disease characterized by severe vascular and inflammatory alterations within the equine foot. This study aimed to develop immunohistochemistry (IHC) protocols for the detection of cyclooxygenase-2 (COX-2) and von Willebrand factor (vWF) in equine feet with and without laminitis, post-mortem perfused with paraffin oil. Unassigned: A total of 12 equine forelimbs from 8 horses were utilized in this study, divided into two study cohorts: one with laminitis and the other as a non-laminitis control. To develop the IHC protocols thoroughly, the tiss...
Harpke M, Brangsch H, Melzer F.In Germany, Contagious Equine Metritis (CEM) is a persistent problem in equine populations. The often subclinical nature of the disease, which is caused by the bacterium Taylorella equigenitalis, poses a problem for the breeding industry. However, there is a lack of knowledge about the genomic diversity of the pathogen in Germany, as studies on the genome level are lacking. Thus, in this study we sequenced 63 T. equigenitalis isolates from a strain collection and contemporary clinical isolates from before 2007-2024. Most of these isolates came from Icelandic horses in southern Germany. Based...
Nowicka B, Łopuszyński W, Krajewska-Wędzina M, Biazik A, Sobuś M, Polkowska I, Szacawa E.Gastrointestinal mycobacteriosis in horses is difficult to diagnose because of the pathogen's intracellular nature and the non-specific clinical symptoms. Effective accurate diagnosis facilitates prognosis and treatment. Current diagnostic procedures and methods of collecting material do not permit definitive antemortem diagnosis. However, culturing, acid-fast bacilli staining, histopathology, PCR and immunological marker evaluation may prove useful. Unassigned: Three horses were admitted to a clinic for intensive care and a final diagnosis. Physical examination and additional tests were perfo...
Silva JG, Martins KR, Rahal NM, Schuch LFD, Cunha RC, Meireles MCA.Neorickettsia risticii, an obligate intracellular bacterium, is the causative agent of Potomac Horse Fever (PHF) - a systemic, acute, and potentially fatal diarrheal disease. This pathogen is an endosymbiont of digenetic trematodes, with freshwater snails playing a role in its biological cycle. The disease exhibits endemic and seasonal patterns, primarily affecting horses in wetlands during warmer months, and has been documented in the United States, Canada, Europe, and South America. Previous studies confirmed the pathogen's presence in herds from southern Brazil via serology and PCR; however...
Atasoy MO, Turan T, Özbek R, Işıdan H, Naggar RFE, Afify AF, Rohaim MA.The genus (HCV) has long been a dynamic group, increasing its number by myriads of species collectively referred to as non-primate hepaciviruses (NPHVs). NPHV exhibits a broad hepatotropism and is often attributed to chronic infection in horses and dogs. However, recent studies and meta-analyses on NPHV in horses have remained inconclusive regarding the determination of risk factors for infection. Therefore, our main goal was to investigate the frequencies and molecular characteristics of NPHV infection linked to geographical location, horse breeds, genders, and ages. For this purpose, we tes...
Healy SR, Yaffy D, Miller HG.Setaria equina is a species of filarial nematode parasite transmitted by mosquitoes, which infects horses and other equids. Adult worms reside in the abdominal cavity with apparently little pathogenic significance, but larvae can migrate to other regions of the body with resulting clinical disease. Cases in the UK are rare, with the last published report in 2001. A recent case of S. equina infection was detected in a 13-year-old, UK-resident mare during postmortem examination in Hertfordshire, UK. Adult worms were collected from the abdominal cavity, their DNA extracted and subjected to PCR an...
In 2017, Spain reported its first equine infectious anemia virus (EIAV) outbreak in 34 years, affecting three horses in two unrelated holdings in Candeleda (Ávila) and Serradilla (Cáceres), with no apparent epidemiological link between premises. Phylogenetic analysis of whole genome and the gene revealed that the Spanish EIAV strains form a distinct monophyletic clade, sharing more than 99% nucleotide identity, suggesting a common contamination event. Interestingly, these three viral strains seem to cluster with North American strains, sharing up to 80.12% nucleotide identity, notably with ...
Ozger ZB, Cihan P, Ozaydin I.Artificial intelligence (AI) has emerged as one of the most transformative tools for developing clinical decision-support systems in veterinary medicine. Despite its growing use, its full potential remains underutilized in equine medicine, an area of both high economic and clinical importance. Accurate survival prediction in horses with colic is crucial for timely intervention and improved clinical outcomes. Methods: This study aimed to predict survival outcomes in horse colic cases by developing models that combine traditional machine-learning algorithms (XGBoost, Light Gradient Boosting Mach...
McAdams ZL, Campbell EJ, Dorfmeyer RA, Turner G, Shaffer S, Ford T, Lawson J, Terry J, Raju M, Coghill L, Cresci L, Lascola K, Pridgen T....Horses and other equids are reliant on the gut microbiome for health, and studies have reported associations between certain clinical conditions and features of the fecal microbiome. However, research to date on the equine fecal microbiome has often relied on small sample sizes collected from single and relatively localized geographic regions. Previous work also largely employs single timepoint analyses, or horses selected based on limited health criteria. Results: To address these limitations and expand our understanding of the core microbiome in health, and the changes associated with advers...
Mules (Equus mulus), as sterile hybrids between mares and donkeys, present a unique uterine morphology and physiology that remains poorly characterized. This study provides the first histomorphometric evaluation and transcriptional profiling of the endometrium in adult mules. To achieve this, endometrial biopsies were analysed using quantitative stereology, histological classification (Kenney-Doig system), and qPCR of key immune-related and fibrotic genes. Histometric analyses revealed that the stratum spongiosum was the predominant component of the mule endometrium (mean volume density: 84.7...
Almaqhawi AA, El-Jalii IM, Al-Sabi MNS, Al-Ali A, Khalid AM, Abduljawad M, Shawaf T.Equine babesiosis is a widespread protozoan disease in Saudi Arabia. The most common finding of clinical babesiosis is splenomegaly, which can be detected using non-invasive splenic ultrasonography. Unassigned: This study aimed to investigate changes in the spleen size in horses infected with babesiosis using ultrasonography before and after treatment. Unassigned: This study employed 15 male and female Arabian horses. Each animal was examined clinically for clinical signs, and blood samples were collected in plain tubes to detect antibodies against . The spleens of healthy and affected horses ...
Costa VMD, de Aguiar Filho RN, Braz GF, Paz CFR, Drumond BP, Teixeira BM, Kroon EG.Equine infectious anemia (EIA) is a chronic disease caused by the equine infectious anemia virus (EIAV), a member of the Retroviridae family and the Lentivirus genus. Most infected animals are asymptomatic carriers, which makes clinical diagnosis challenging. This study aimed to conduct a clinical and laboratory evaluation of EIA in equids used for equestrian tourism in Jericoacoara National Park, Ceará, Brazil. A total of 112 equids (104 horses and 8 mules) underwent clinical, hematological, biochemical, serological, and molecular assessments. The EIAV seropositivity rates were 11.6% by AGID...
Morales J, Ruano MJ, Tena-Tomás C, van Schalkwyk A, Loundras EA, Valero-Lorenzo M, López-Herranz A, Romito M, Batten C, Villalba R, Agüero M.African horse sickness (AHS) is a disease affecting equids caused by the AHS virus (AHSV). The World Organisation for Animal Health (WOAH) includes AHS as a notifiable disease and, upon detection within the European Union, immediate control and eradication measures are mandated. Thus, validated diagnostic methods for rapid AHSV detection are essential. The Agüero 2008 and Guthrie 2013 rRT-PCR methods have been widely validated for detection of any AHSV strain and are included as reference rRT-PCRs in the WOAH manual. However, the WOAH Reference Laboratory for AHS in the Republic of South Afri...
Lawson JM, Verheyen KL, Laroucau K, Bryan JS, Smith KC, Foote AK, de Mestre AM.Umbilical cord torsion (UCT) is the most frequent pathology of the equine umbilical cord (UC) and a prominent cause of abortion, yet objective data on its features remain limited. This study compared UCT with clinically normal pregnancies (CNP) to (i) identify gross and histological features of the UC and fetal membranes, (ii) determine whether UCT is associated with fetal growth restriction, and (iii) rule out infectious aetiologies. Gross and histological features of the UC, chorioallantois and amnion were compared between groups. Fetal weight and crown-rump length were analysed relative to ...
Hellige M, Schröder C, Seehusen F, Rohn K, Geburek F.Computed tomographic myelography (CTM) is diagnostic for extradural spinal cord compression but knowledge about vertebral ratios from transverse images in flexion and normal position of unaffected horses is lacking. Objective: To compare the ratios of the cross-sectional areas (CSAs) of the spinal cord, the vertebral canal and of the contrast enhanced dural tube on transverse CTM images at C3-C4 in neutral and flexed positions in unaffected Warmbloods. Methods: CTM was performed in 13 neurologically unaffected Warmbloods in neutral and flexed cervical vertebral column positions. Ratios were ca...
Castanheira CIGD, Taylor S, Skiöldebrand E, Rubio-Martinez LM, Hackl M, Clegg PD, Peffers MJ.The aim of this study was to identify differentially expressed microRNAs (miRNAs) in serum and synovial fluid (SF) samples of control horses and those with osteoarthritis (OA) to identify potential candidates for biomarkers of disease. Total RNA was extracted from serum and SF samples of control (n = 4) and OA (n = 9) horses and sequenced. Differential expression analysis, pathway analysis and miRNA target prediction were performed. A group of six miRNAs (eca-miR-199a-3p, eca-miR-148a, eca-miR-99b, eca-miR-146a, eca-miR-423-5p and eca-miR-23b) was selected for validation in an independent coho...
Hananeh W, Al Rukibat R, Hammad H, Mukbel R.Leishmaniosis is an endemic parasitic infection in Jordan and the Middle East. Despite the endemicity of leishmaniosis in Jordan and frequently reported humancases, no singleclinical case has been documented in animals throughout the country. This report documents the first two animal Leishmania cases in two different animal species with a current literature review. Cutaneous leishmaniosis was diagnosed in an adult horse that presented with multiple variably sized skin nodules, some of which ulcerated. Visceral leishmaniosis was diagnosed in a stray dog. Cytological, histopathological, and mol...
Haywood LMB, Clark A, Hause B, Sheahan B.Many cases of equine enterocolitis are suspected to be infectious in nature, but no pathogen is identified in many cases. Objective: Perform next-generation sequencing on faeces collected from cases of equine enterocolitis for the presence of novel viruses and determine if an identified novel virus is associated with cases of equine enterocolitis. Methods: Retrospective cohort study. Methods: Next generation sequencing was performed targeting viral genomes from n = 13 pooled faecal samples (n = 5 horses/pool) with enterocolitis. Subsequent qPCR was performed targeting the highly conser...
Kyle-LaBell E, Andersson A, Baughman B.Fibrocartilaginous embolic myelopathy (FCE) was diagnosed in a 15-year-old pony mare by histopathologic examination of the spinal cord. The horse was euthanized and submitted for necropsy following focal seizures and lateral recumbency for approximately 12 h. Histopathology of spinal cord segments C5-C7 revealed severe ischemic myelomalacia with intravascular amorphous material that stained positive with Alcian Blue, consistent with cartilaginous matrix. These features in addition to the acute onset of clinical signs are characteristic for FCE. This case report describes the clinical and histo...
Harel B, Sévin C, Le Hello S, Moreau P, Giard JC, Petry S, Gravey F.Enterobacteriaceae are opportunistic pathogens responsible for local or systemic infections in both human and veterinary medicine. To monitor circulating strains in stud farms in Normandy (France), we investigated a collection of Enterobacteriaceae isolated from necropsied equids performed in the region between 1997 and 2020. These strains were initially identified using MALDI-TOF; however, as this method failed to identify some isolates, whole genome sequencing followed by rMLST analysis was subsequently performed. Different genera were identified: Enterobacter spp., Huaxiibacter spp., Lellio...
Gleerup KB, Forkman B, Lindegaard C, Andersen PH.The objective of this study was to investigate the existence of an equine pain face and to describe this in detail. Methods: Semi-randomized, controlled, crossover trial. Methods: Six adult horses. Methods: Pain was induced with two noxious stimuli, a tourniquet on the antebrachium and topical application of capsaicin. All horses participated in two control trials and received both noxious stimuli twice, once with and once without an observer present. During all sessions their pain state was scored. The horses were filmed and the close-up video recordings of the faces were analysed for alterat...
McIlwraith CW, Frisbie DD, Kawcak CE, Fuller CJ, Hurtig M, Cruz A.Equine models of osteoarthritis (OA) have been used to investigate pathogenic pathways of OA and evaluate therapeutic candidates for naturally occurring equine OA which is a significant clinical disease in the horse. This review focuses on the macroscopic and microscopic criteria for assessing naturally occurring OA in the equine metacarpophalangeal joint as well as the osteochondral fragment-exercise model of OA in the equine middle carpal joint. Methods: A review was conducted of all published OA studies using horses and the most common macroscopic and microscopic scoring systems were summar...
Sangioni LA, Horta MC, Vianna MC, Gennari SM, Soares RM, Galvão MA, Schumaker TT, Ferreira F, Vidotto O, Labruna MB.We compared the rickettsial infection status of Amblyomma cajennense ticks, humans, dogs, and horses in both Brazilian spotted fever (BSF)-endemic and -nonendemic areas in the state of Sao Paulo, Brazil. Most of the horses and few dogs from BSF-endemic areas had serologic titers against Rickettsia rickettsii antigens. In contrast, no dogs or horses from BSF-nonendemic areas had serologic titers against R. rickettsii antigens, although they were continually exposed to A. cajennense ticks. All human serum samples and ticks from both areas were negative by serologic assay and polymerase chain rea...
Durham AE, Frank N, McGowan CM, Menzies-Gow NJ, Roelfsema E, Vervuert I, Feige K, Fey K.Equine metabolic syndrome (EMS) is a widely recognized collection of risk factors for endocrinopathic laminitis. The most important of these risk factors is insulin dysregulation (ID). Clinicians and horse owners must recognize the presence of these risk factors so that they can be targeted and controlled to reduce the risk of laminitis attacks. Diagnosis of EMS is based partly on the horse's history and clinical examination findings, and partly on laboratory testing. Several choices of test exist which examine different facets of ID and other related metabolic disturbances. EMS is controlled ...
Wise LN, Kappmeyer LS, Mealey RH, Knowles DP.Equine piroplasmosis is caused by one of 2 erythrocytic parasites Babesia caballi or Theileria equi. Although the genus of the latter remains controversial, the most recent designation, Theileria, is utilized in this review. Shared pathogenesis includes tick-borne transmission and erythrolysis leading to anemia as the primary clinical outcome. Although both parasites are able to persist indefinitely in their equid hosts, thus far, only B. caballi transmits across tick generations. Pathogenesis further diverges after transmission to equids in that B. caballi immediately infects erythrocytes, wh...
Murgue B, Murri S, Zientara S, Durand B, Durand JP, Zeller H.On September 6, 2000, two cases of equine encephalitis caused by West Nile (WN) virus were reported in southern France (Hérault Province), near Camargue National Park, where a WN outbreak occurred in 1962. Through November 30, 76 cases were laboratory confirmed among 131 equines with neurologic disorders. The last confirmed case was on November 3, 2000. All but three cases were located in a region nicknamed "la petite Camargue," which has several large marshes, numerous colonies of migratory and resident birds, and large mosquito populations. No human case has been confirmed among clinically ...
Seyedmousavi S, Guillot J, Arné P, de Hoog GS, Mouton JW, Melchers WJ, Verweij PE.The importance of aspergillosis in humans and various animal species has increased over the last decades. Aspergillus species are found worldwide in humans and in almost all domestic animals and birds as well as in many wild species, causing a wide range of diseases from localized infections to fatal disseminated diseases, as well as allergic responses to inhaled conidia. Some prevalent forms of animal aspergillosis are invasive fatal infections in sea fan corals, stonebrood mummification in honey bees, pulmonary and air sac infection in birds, mycotic abortion and mammary gland infections in ...
Ytrehus B, Carlson CS, Ekman S.Osteochondrosis is a common and clinically important joint disorder that occurs in human beings and in multiple animal species, most commonly pigs, horses, and dogs. This disorder is defined as a focal disturbance of enchondral ossification and is regarded as having a multifactorial etiology, with no single factor accounting for all aspects of the disease. The most commonly cited etiologic factors are heredity, rapid growth, anatomic conformation, trauma, and dietary imbalances; however, only heredity and anatomic conformation are well supported by the scientific literature. The way in which t...
Habarugira G, Suen WW, Hobson-Peters J, Hall RA, Bielefeldt-Ohmann H.West Nile virus (WNV) is an important zoonotic flavivirus responsible for mild fever to severe, lethal neuroinvasive disease in humans, horses, birds, and other wildlife species. Since its discovery, WNV has caused multiple human and animal disease outbreaks in all continents, except Antarctica. Infections are associated with economic losses, mainly due to the cost of treatment of infected patients, control programmes, and loss of animals and animal products. The pathogenesis of WNV has been extensively investigated in natural hosts as well as in several animal models, including rodents, lagom...
Wang LF, Yu M, Hansson E, Pritchard LI, Shiell B, Michalski WP, Eaton BT.An outbreak of acute respiratory disease in Hendra, a suburb of Brisbane, Australia, in September 1994 resulted in the deaths of 14 racing horses and a horse trainer. The causative agent was a new member of the family Paramyxoviridae. The virus was originally called Equine morbillivirus but was renamed Hendra virus (HeV) when molecular characterization highlighted differences between it and members of the genus Morbillivirus. Less than 5 years later, the closely related Nipah virus (NiV) emerged in Malaysia, spread rapidly through the pig population, and caused the deaths of over 100 people. W...
Barlough JE, Madigan JE, DeRock E, Bigornia L.A nested polymerase chain reaction for detecting Ehrlichia equi in horses and ticks (Ixodes pacificus) was developed. A major second-round PCR product of 928 bp could be readily visualized in ethidium bromide-stained agarose minigels. An internal probe was used to verify the identity of the amplified product by non-radioactive (digoxigenin-based) Southern blotting; additional confirmation was provided by DNA sequence analysis. A dilution study testing the sensitivity of the PCR indicated that DNA derived from 3 infected neutrophils was sufficient to generate a PCR signal. The specificity of t...
Nugent J, Birch-Machin I, Smith KC, Mumford JA, Swann Z, Newton JR, Bowden RJ, Allen GP, Davis-Poynter N.Equid herpesvirus 1 (EHV-1) can cause a wide spectrum of diseases ranging from inapparent respiratory infection to the induction of abortion and, in extreme cases, neurological disease resulting in paralysis and ultimately death. It has been suggested that distinct strains of EHV-1 that differ in pathogenic capacity circulate in the field. In order to investigate this hypothesis, it was necessary to identify genetic markers that allow subgroups of related strains to be identified. We have determined all of the genetic differences between a neuropathogenic strain (Ab4) and a nonneuropathogenic ...
van Kasteren PB, Bailey-Elkin BA, James TW, Ninaber DK, Beugeling C, Khajehpour M, Snijder EJ, Mark BL, Kikkert M.Protein ubiquitination regulates important innate immune responses. The discovery of viruses encoding deubiquitinating enzymes (DUBs) suggests they remove ubiquitin to evade ubiquitin-dependent antiviral responses; however, this has never been conclusively demonstrated in virus-infected cells. Arteriviruses are economically important positive-stranded RNA viruses that encode an ovarian tumor (OTU) domain DUB known as papain-like protease 2 (PLP2). This enzyme is essential for arterivirus replication by cleaving a site within the viral replicase polyproteins and also removes ubiquitin from cell...
Hauck SM, Dietter J, Kramer RL, Hofmaier F, Zipplies JK, Amann B, Feuchtinger A, Deeg CA, Ueffing M.Autoimmune uveitis is a blinding disease presenting with autoantibodies against eye-specific proteins as well as autoagressive T cells invading and attacking the immune-privileged target tissue retina. The molecular events enabling T cells to invade and attack the tissue have remained elusive. Changes in membrane protein expression patterns between diseased and healthy stages are especially interesting because initiating events of disease will most likely occur at membranes. Since disease progression is accompanied with a break-down of the blood-retinal barrier, serum-derived proteins mask the...
Bunning ML, Bowen RA, Cropp CB, Sullivan KG, Davis BS, Komar N, Godsey MS, Baker D, Hettler DL, Holmes DA, Biggerstaff BJ, Mitchell CJ.A total of 12 horses of different breeds and ages were infected with West Nile virus (WNV) via the bites of infected Aedes albopictus mosquitoes. Half the horses were infected with a viral isolate from the brain of a horse (BC787), and half were infected with an isolate from crow brain (NY99-6625); both were NY99 isolates. Postinfection, uninfected female Ae. albopictus fed on eight of the infected horses. In the first trial, Nt antibody titers reached >1:320, 1:20, 1:160, and 1:80 for horses 1 to 4, respectively. In the second trial, the seven horses with subclinical infections developed Nt a...
Guy JS, Breslin JJ, Breuhaus B, Vivrette S, Smith LG.A coronavirus was isolated from feces of a diarrheic foal and serially propagated in human rectal adenocarcinoma (HRT-18) cells. Antigenic and genomic characterizations of the virus (isolate NC99) were based on serological comparison with other avian and mammalian coronaviruses and sequence analysis of the nucleocapsid (N) protein gene. Indirect fluorescent-antibody assay procedures and virus neutralization assays demonstrated a close antigenic relationship with bovine coronavirus (BCV) and porcine hemagglutinating encephalomyelitis virus (mammalian group 2 coronaviruses). Using previously des...
Snijder EJ, Wassenaar AL, Spaan WJ.To study the proteolytic processing of the equine arteritis virus (EAV) replicase open reading frame 1a (ORF1a) protein, specific antisera were raised in rabbits, with six synthetic peptides and a bacterial fusion protein as antigens. The processing of the EAV ORF1a product in infected cells was analyzed with Western blot (immunoblot) and immunoprecipitation techniques. Additional information was obtained from transient expression of ORF1a cDNA constructs. The 187-kDa ORF1a protein was found to be subject to at least five proteolytic cleavages. The processing scheme, which covers the entire OR...
Marklund L, Moller MJ, Sandberg K, Andersson L.The melanocyte-stimulating hormone receptor gene (MC1R) is the major candidate gene for the chestnut coat color in horses since it is assumed to be controlled by an allele at the extension locus. MC1R sequences were PCR amplified from chestnut (e/e) and non-chestnut (E/-) horses. A single-strand conformation polymorphism was found that showed a complete association to the chestnut coat color among 144 horses representing 12 breeds. Sequence analysis revealed a single missense mutation (83Ser-->Phe) in the MC1R allele associated with the chestnut color. The substitution occurs in the second ...
Steelman SM, Chowdhary BP, Dowd S, Suchodolski J, Janečka JE.The nutrition and health of horses is closely tied to their gastrointestinal microflora. Gut bacteria break down plant structural carbohydrates and produce volatile fatty acids, which are a major source of energy for horses. Bacterial communities are also essential for maintaining gut homeostasis and have been hypothesized to contribute to various diseases including laminitis. We performed pyrosequencing of 16S rRNA bacterial genes isolated from fecal material to characterize hindgut bacterial communities in healthy horses and those with chronic laminitis. Results: Fecal samples were collected...
Rogers GN, Pritchett TJ, Lane JL, Paulson JC.Human and animal (avian and equine) influenza A virus isolates of the H3 serotype exhibit marked differences in their ability to bind specific sialyloligosaccharide sequences that serve as cell surface receptor determinants (G. Rogers and J. Paulson, 1983, Virology 127, 361-373). Whereas human isolates of this subtype strongly agglutinate enzymatically modified human erythrocytes containing the terminal SA alpha 2,6Gal sequence, avian and equine isolates preferentially agglutinate erythrocytes bearing the SA alpha 2, 3Gal sequence. As shown in this report, a glycoprotein found in horse serum, ...
Dutkiewicz J, Mackiewicz B, Kinga Lemieszek M, Golec M, Milanowski J.Pantoea agglomerans, a bacterium associated with plants, is not an obligate infectious agent in humans. However, it could be a cause of opportunistic human infections, mostly by wound infection with plant material, or as a hospital-acquired infection, mostly in immunocompromised individuals. Wound infection with P. agglomerans usually follow piercing or laceration of skin with a plant thorn, wooden splinter or other plant material and subsequent inoculation of the plant-residing bacteria, mostly during performing of agricultural occupations and gardening, or children playing. Septic arthritis ...
Dougal K, de la Fuente G, Harris PA, Girdwood SE, Pinloche E, Newbold CJ.The horse has a rich and complex microbial community within its gastrointestinal tract that plays a central role in both health and disease. The horse receives much of its dietary energy through microbial hydrolysis and fermentation of fiber predominantly in the large intestine/hindgut. The presence of a possible core bacterial community in the equine large intestine was investigated in this study. Samples were taken from the terminal ileum and 7 regions of the large intestine from ten animals, DNA extracted and the V1-V2 regions of 16SrDNA 454-pyrosequenced. A specific group of OTUs clustered...
Garmashova N, Atasheva S, Kang W, Weaver SC, Frolova E, Frolov I.The encephalitogenic New World alphaviruses, including Venezuelan (VEEV), eastern (EEEV), and western equine encephalitis viruses, constitute a continuing public health threat in the United States. They circulate in Central, South, and North America and have the ability to cause fatal disease in humans and in horses and other domestic animals. We recently demonstrated that these viruses have developed the ability to interfere with cellular transcription and use it as a means of downregulating a cellular antiviral response. The results of the present study suggest that the N-terminal, approxima...
Love S, Murphy D, Mellor D.Cyathostomes are now the principle parasitic pathogen of the horse: a remarkable transformation during the last 25 years from virtual obscurity to focus of attention in equine parasitology. This rise to prominence coincides with the marked decrease in prevalence of large strongyle infections as a result of widespread use of modern anthelmintic compounds. On the basis that strongyle-associated diseases continue to commonly occur in the absence of these large strongyle species, clinical attention has turned to the pathogenicity of cyathostomes. Although many horses harbour burdens of tens of tho...
Savini G, Afonso A, Mellor P, Aradaib I, Yadin H, Sanaa M, Wilson W, Monaco F, Domingo M.Epizootic haemorrhagic disease (EHD) is an infectious non-contagious viral disease transmitted by insects of the genus Culicoides which affects wild and domestic ruminants. The causative agent, the epizootic haemorrhagic disease virus (EHDV), belongs to the family Reoviridae, genus Orbivirus and shares many morphological and structural characteristics with the other members of the genus such as bluetongue, African horse sickness and equine encephalosis viruses. In recent years EHD outbreaks have been reported in countries bordering the European Union. They caused disease in cattle and severe r...
Singh S, Jindal AK, Pilania RK.Kawasaki disease (KD) is a medium vessel vasculitis with predilection for coronary arteries. Due to lack of a reliable confirmatory laboratory test, the diagnosis of KD is based on a constellation of clinical findings that appear in a typical temporal sequence. These diagnostic criteria have been modified from time to time and the most recent guidelines have been proposed by the American Heart Association (AHA) in 2017. However, several children may have incomplete or atypical forms of KD and the diagnosis can often be difficult, especially in infants and young children. In this review, we hav...
