Infectious diseases in horses encompass a range of illnesses caused by bacteria, viruses, fungi, or parasites. These diseases can affect various systems within the equine body, leading to symptoms that range from mild discomfort to severe systemic illness. Common infectious diseases in horses include equine influenza, strangles, equine herpesvirus, and West Nile virus. These diseases can be transmitted through direct contact with infected animals, contaminated surfaces, or vectors such as insects. Understanding the mechanisms of transmission, pathogenesis, and immune response is essential for effective prevention and control. This page compiles peer-reviewed research studies and scholarly articles that explore the epidemiology, diagnosis, treatment, and management of infectious diseases in horses.
Abad-Cobo A, Llorente F, Barbero MDC, Cruz-López F, Forés P, Jiménez-Clavero MÁ.West Nile fever/encephalitis (WNF) is an infectious disease affecting horses, birds and humans, with a cycle involving birds as natural reservoirs and mosquitoes as transmission vectors. It is a notifiable disease, re-emerging in Europe. In Spain, it first appeared in horses in the south (Andalusia) in 2010, where outbreaks occur every year since. However, in 2014, an outbreak was declared in horses in central Spain, approximately 200 km away from the closest foci in Andalusia. Before that, evidence of West Nile virus (WNV) circulation in central Spain had been obtained only from wildlife, bu...
Staiger EA, Tseng CT, Miller D, Cassano JM, Nasir L, Garrick D, Brooks SA, Antczak DF.The common equine skin tumors known as sarcoids have been causally associated with infection by bovine papillomavirus (BPV). Additionally, there is evidence for host genetic susceptibility to sarcoids. We investigated the genetic basis of susceptibility to sarcoid tumors on a cohort of 82 affected horses and 270 controls genotyped on a genome-wide platform and two custom panels. A Genome Wide Association Study (GWAS) identified candidate regions on six chromosomes. Bayesian probability analysis of the same dataset verified only the regions on equine chromosomes (ECA) 20 and 22. Fine mapping us...
Peel AJ, Field HE, Reid PA, Plowright RK, Broder CC, Skerratt LF, Hayman DT, Restif O, Taylor M, Martin G, Crameri G, Smith I, Baker M, Marsh GA....No abstract available
Walter S, Bollenbach A, Doerrbecker J, Pfaender S, Brown RJP, Vieyres G, Scott C, Foster R, Kumar A, Zitzmann N, Griffin S, Penin F, Pietschmann T....Nonprimate hepacivirus (NPHV), the closest homolog of hepatitis C virus (HCV) described to date, has recently been discovered in horses. Even though the two viruses share a similar genomic organization, conservation of the encoded hepaciviral proteins remains undetermined. The HCV p7 protein is localized within endoplasmic reticulum (ER) membranes and is important for the production of infectious particles. In this study, we analyzed the structural and functional features of NPHV p7 in addition to its role during virus assembly. Three-dimensional homology models for NPHV p7 using various nucle...
Kumar N, Bera BC, Greenbaum BD, Bhatia S, Sood R, Selvaraj P, Anand T, Tripathi BN, Virmani N.Equine influenza viruses (EIVs) of H3N8 subtype are culprits of severe acute respiratory infections in horses, and are still responsible for significant outbreaks worldwide. Adaptability of influenza viruses to a particular host is significantly influenced by their codon usage preference, due to an absolute dependence on the host cellular machinery for their replication. In the present study, we analyzed genome-wide codon usage patterns in 92 EIV strains, including both H3N8 and H7N7 subtypes by computing several codon usage indices and applying multivariate statistical methods. Relative synon...
Laroucau K, Colaneri C, Jaÿ M, Corde Y, Drapeau A, Durand B, Zientara S, Beck C.To evaluate the routine complement fixation test (CFT) used to detect Burkholderia mallei antibodies in equine sera, an interlaboratory proficiency test was held with 24 European laboratories, including 22 National Reference Laboratories for glanders. The panels sent to participants were composed of sera with or without B mallei antibodies. This study confirmed the reliability of CFT and highlighted its intralaboratory reproducibility. However, the sensitivity of glanders serodiagnosis and laboratory proficiency may be improved by standardising critical reagents, including antigens, and by dev...
Hedegaard CJ, Heegaard PM.Immunisation by administration of antibodies (immunoglobulins) has been known for more than one hundred years as a very efficient means of obtaining immediate, short-lived protection against infection and/or against the disease-causing effects of toxins from microbial pathogens and from other sources. Thus, due to its rapid action, passive immunisation is often used to treat disease caused by infection and/or toxin exposure. However immunoglobulins may also be administered prior to exposure to infection and/or toxin, although they will not provide long-lasting protection as is seen with active...
Johnson AL, McAdams-Gallagher SC, Aceto H.The laboratory diagnosis of botulism in horses traditionally has relied upon the mouse bioassay (MBA). The accuracy of this test for the diagnosis of botulism in horses is unknown. Objective: Our goal was to determine the sensitivity, specificity, positive predictive value, and negative predictive value of the MBA on laboratory-processed fecal and gastrointestinal samples for foals and adult horses. Methods: Cases included all horses with a final clinical diagnosis of botulism that were admitted between 1986 and 2011 and had MBA testing performed. Controls included horses without botulism that...
Kuroda T, Kinoshita Y, Niwa H, Shinzaki Y, Tamura N, Hobo S, Kuwano A.Meticillin-resistant Staphylococcus aureus (MRSA) infections have been confirmed in hospitalised Thoroughbred racehorses at the hospitals of two training centres in Japan since 2009. To investigate the source of infection, the authors examined the rate of nasal MRSA colonisation in 600 healthy Thoroughbred racehorses, 53 veterinarians and 16 office staff at the racehorse hospitals of the two training centres. MRSA was not isolated from healthy Thoroughbred racehorses or hospital office staff. However, MRSA was isolated from 16 veterinarians (30.1 per cent), and the colonisation rate was signif...
Andrews ES, Turell MJ.Emerging and re-emerging arboviruses continue to be a threat to global public health, and viral surveillance of mosquito populations is critical for mosquito control operations. Due to the tropical climate of many of the affected areas, it may be difficult to maintain a cold chain as the samples travel from collection sites to laboratories for testing. We determined how suboptimal holding temperatures affected the ability to detect viruses in pools of mosquitoes. Adult female Aedes albopictus and Ae. taeniorhynchus individuals were inoculated with chikungunya virus or Venezuelan equine encepha...
Bassarak B, Moser I, Menge C.A modified Baltz's in vitro cultivation system for the propagation of Trypanosoma equiperdum strain OVI was established to develop a replacement for the conventional production procedure of dourine diagnostic antigen in rats. To increase trypanosome yields we designed an optimized culture medium by addition of supplemental compounds. Trypanosomes were adapted to this medium by two succeeding cultivation steps which led to a substantial proliferation rate and an increased cell density tolerance, respectively. As a result, adapted parasites could be propagated to maximum cell densities of >2...
Cauchard S, Van Reet N, Büscher P, Goux D, Grötzinger J, Leippe M, Cattoir V, Laugier C, Cauchard J.Trypanozoon parasites infect both humans, causing sleeping sickness, and animals, causing nagana, surra, and dourine. Control of nagana and surra depends to a great extent on chemotherapy. However, drug resistance to several of the front-line drugs is rising. Furthermore, there is no official treatment for dourine. Therefore, there is an urgent need to develop antiparasitic agents with novel modes of action. Host defense peptides have recently gained attention as promising candidates. We have previously reported that one such peptide, the equine antimicrobial peptide eCATH1, is highly active a...
Habibi G, Esmaeilnia K, Hablolvarid MH, Afshari A, Zamen M, Bozorgi S.Equine piroplasmosis (EP) is the cause of persistent tick-borne infection with no symptoms, but the most important problem of EP is due to the persistent carrier state. Carrier animals to Babesia (Theileria) equi (Laveran 1901) and B. caballi (Nuttall, 1910) infestation could be identified by extremely sensitive PCR-based method. The purpose of this study was to identify the causative agents of equine piroplasmosis based on molecular and microscopic assays in equids from Kurdistan Province, Iran. Methods: Thirty one horse and mule blood samples were used with history of living in Kurdistan Pro...
Kumar J, Chaudhury A, Yadav SC.Trypanosomosis (Surra) is an economically important disease caused by Trypanosoma evansi which is an extracellular parasite present in the plasma, tissues and other body fluids of a wide range of hosts including domesticated animals. Currently, serological reports are based on detection of antibodies by ELISA using whole cell lysate (WCL) antigen, which has a limitation of persistence of anti-trypanosomal antibodies after successful treatment of the disease. Moreover, it has some ethical issues also like requirement of mice for in vivo maintenance of parasite for preparing the antigen. Therefo...
Sánchez-Matamoros A, Nieto-Pelegrín E, Beck C, Rivera-Arroyo B, Lecollinet S, Sailleau C, Zientara S, Sánchez-Vizcaíno JM.African horse sickness (AHS) is considered a fatal re-emergent vector-borne disease of horses. In the absence of any effective treatment for AHS, vaccination remains the most effective form of disease control. The new generation of vaccines, such as one based on purified, inactivated AHS virus (AHSV, serotype 4), which does not induce antibodies against non-structural protein 3 (NS3), enables the development of diagnostic methods that differentiate infected from vaccinated animals (DIVA assays). As detecting AHS in AHSV-free countries may lead to restrictions on international animal movements ...
Davitkov D, Vucicevic M, Stevanovic J, Krstic V, Slijepcevic D, Glavinic U, Stanimirovic Z.Equine piroplasmosis is significant tick-borne disease with wide distribution. The prevalence of equine piroplasmosis in Serbia, Montenegro and Bosnia and Herzegovina is unknown. In aim to obtain a first insight into the prevalence we performed molecular epidemiological study which included 142 horses, on seven locations in these three countries. We first performed PCR for the detection of a 450bp long section of the 18S rRNA of piroplasma-specific region. For all positive samples we have done multiplex PCR for the species detection. Species determination was further confirmed by sequencing PC...
Kalinowski M, Grądzki Z, Jarosz Ł, Kato K, Hieda Y, Kakuda T, Takai S.Rhodococcus equi is an important bacterial pathogen in foals up to 6 months old, widespread in horse farms all over the world. It was found that only virulent R. equi strains expressing 15-17 kDa virulence-associated protein (VapA) and having large virulence plasmid of 85-90 kb containing vapA gene are pathogenic for horses. To date, 12 plasmid types have been reported in VapA positive strains from horses. There are no data concerning plasmid types of Polish field R. equi strains isolated from horses and horse farm environment. The aim of the study is to determine plasmid profiles of virulent ...
Ardo MB, Abubakar DM.A cross-sectional study was conducted on the seroprevalence of horse brucellosis using the Rose Bengal Plate Test (RBPT) and Serum Agglutination Test (SAT) on the Mambilla plateau of Taraba state, Nigeria where horses are reared under a free range management system on cattle farms. The objectives of the study were to determine the prevalence of brucella antibodies in horses as well as the distribution of the infection according to sex and age. A total of 100 horses were sampled, 25 each from four locations where horses were concentrated on the plateau: Gembu, Nguroje, Dorofi, and Mayo Ndaga. S...
Takesue M, Osaka Y, Muranaka M, Katayama Y, Ikadai H.In the present study, the serum and cerebrospinal fluid of horses diagnosed with Setaria digitata cerebrospinal filariasis were analyzed by western blot. The results revealed S. digitata protein bands measuring 65, 34, 22, and 18 kDa in molecular weight. In particular, the 18 kDa band is a possible candidate for clinical immunodiagnosis on the basis of western blot findings.
Jarvis JA, Franke MA, Davis AD.An examination using the routine rabies direct fluorescent antibody test was performed on rabies or Eastern equine encephalitis positive mammalian brain tissue to assess inactivation of the virus. Neither virus was inactivated with acetone fixation nor the routine test, thus laboratory employees should treat all samples as rabies and when appropriate Eastern equine encephalitis positive throughout the whole procedure.
Souza CE, Camargo LB, Pinter A, Donalisio MR.Equines play a role in the epidemiology of Brazilian spotted fever (BSF) since they are a primary host for the tick Amblyomma sculptum. We studied the seroprevalence for three species of Rickettsia in equines in four endemic (with human cases) and in four non-endemic areas (no human cases) in the Piracicaba River Basin, São Paulo, Brazil. A serological survey of 504 equines was performed: around 63 animals were sampled in each area and tested through indirect immunofluorescence assay for R. rickettsii, R. parkeri, and R. bellii in 2012-2013. Blood samples were seropositive for 183 equines (36...
Sherman AB, Clode AB, Gilger BC.To determine the significance of Aspergillus and Fusarium spp., as identified by culture, on clinical outcome in equine keratomycosis. Methods: Retrospective analysis of 66 horses (66 eyes) evaluated at the NCSU-VH diagnosed with keratomycosis from which Aspergillus or Fusarium spp. were cultured. Horses were classified into those who improved with medical management alone or those who required surgical intervention to improve. Horses who underwent surgery were divided into globe-sparing procedures or enucleation. Effects of bacterial co-infection, previous topical steroid or antifungal use, a...
Gardner SN, McLoughlin K, Be NA, Allen J, Weaver SC, Forrester N, Guerbois M, Jaing C.Venezuelan equine encephalitis virus (VEEV) is a mosquito-borne alphavirus that has caused large outbreaks of severe illness in both horses and humans. New approaches are needed to rapidly infer the origin of a newly discovered VEEV strain, estimate its equine amplification and resultant epidemic potential, and predict human virulence phenotype. We performed whole genome single nucleotide polymorphism (SNP) analysis of all available VEE antigenic complex genomes, verified that a SNP-based phylogeny accurately captured the features of a phylogenetic tree based on multiple sequence alignment, an...
Dominguez M, Münstermann S, Murray G, Timoney P.The 'high-health, high-performance' (HHP) horse concept has been developed by the World Organisation for Animal Health (OIE) together with the F6ddration Equestre Internationale and the International Federation of Horseracing Authorities. This concept is outlined in the OIE Terrestrial Animal Health Code (Chapter 4.16). It aims to address impediments to the international movement of competition horses through a harmonised, practically feasible, globally applicable framework based on simplified certification requirements for the temporary importation of HHP horses and for their return to their ...
Information on equine infectious anaemia (EIA) in mules, including those with an equivocal reaction in agar gel immunodiffusion test (AGIDT), is scarce. For this, a study was conducted to evaluate the clinical, viral loads and pathological findings of two groups of naturally infected asymptomatic mules, respectively with a negative/equivocal and positive AGIDT reactivity, which were subjected to pharmacological immune suppression (IS). A non-infected control was included in the study that remained negative during the observation period. Throughout the whole study, even repeated episodes of rec...
Jennings JE.A 21-year-old Appaloosa mare was presented with a pigmented cutaneous mass at the base of the right side of the neck. The diagnosis of phaeohyphomycosis due to pigmented fungi, known as Pyrenophora phaeocomes and Drechslera nobleae, was made based on a histopathology report followed by polymerase chain reaction (PCR) and 18S rRNA gene sequencing. The mass was surgically excised with clean margins, which is usually curative. Une jument Appaloosa âgée de 21 ans a été présentée avec une masse cutanée pigmentée à la base du côté droit du cou. Le diagnostic de phæohyphomycose causée p...
Carfora V, Caprioli A, Grossi I, Pepe M, Alba P, Lorenzetti S, Amoruso R, Sorbara L, Franco A, Battisti A.A Methicillin-resistantStaphylococcus aureus(MRSA) was isolated in Italy from a pathological sample of a mare presenting chronic purulent sinusitis and that had undergone frontal-sinus surgery three months before. Humans, horses, dogs and environmental samples were subsequently collected at the mare's stable and at the Veterinary Hospital, where the mare was operated/hospitalized, and screened for the presence of MRSA that was detected from other horses and from the environment at both sites. All the MRSA isolates belonged to clonal complex (CC)8, ST8-t11469-SCCmec-IVa, and showed similar phen...
Terron-Canedo N, Weir W, Nicolson L, Britton C, Nasir L.Bovine papillomavirus (BPV) types 1 and 2 play an important role in the pathogenesis of equine sarcoids (ES), the most common cutaneous tumour affecting horses. MicroRNAs (miRNAs), small non-coding RNAs that regulate essential biological and cellular processes, have been found dysregulated in a wide range of tumours. The aim of this study was to identify miRNAs associated with ES. Differential expression of miRNAs was assessed in control equine fibroblasts (EqPalFs) and EqPalFs transformed with the BPV-1 genome (S6-2 cells). Using a commercially available miRNA microarray, 492 mature miRNAs we...
Breathnach CC, Yeargan MR, Sheoran AS, Allen GP.Equine herpesvirus-1 (EHV-1) remains a frequent cause of upper respiratory tract infection and abortion in horses worldwide. However, little is known about the local antibody response elicited in the upper airways of horses following exposure to EHV-1. This study analysed the mucosal humoral immune response of weanling foals following experimental infection with virulent EHV-1, or vaccination with either of 2 commercial vaccines. Twenty weanlings were assigned to 5 groups and were inoculated with, or vaccinated against, EHV-1 following different regimens. Finally, all weanlings were simultaneo...
Lawton KOY, Arthur RM, Moeller BC, Barnum S, Pusterla N.More and more studies are reporting on the natural transmission of SARS-CoV-2 between humans with COVID-19 and their companion animals (dogs and cats). While horses are apparently susceptible to SARS-CoV-2 infection based on the homology between the human and the equine ACE-2 receptor, no clinical or subclinical infection has yet been reported in the equine species. To investigate the possible clinical role of SARS-CoV-2 in equids, nasal secretions from 667 horses with acute onset of fever and respiratory signs were tested for the presence of SARS-CoV-2 by qPCR. The samples were collected from...
Hildreth SW, Beaty BJ, Maxfield HK, Gilfillan RF, Rosenau BJ.Enzyme immunoassays (EIAs) for eastern equine encephalomyelitis (EEE) and Highlands J (HJ) virus antigens were compared in a retrospective study with standard virus isolation procedures (VIP) for detection of alpha virus-infected mosquito pools. The original VIP was a plaque assay in chick embryo cell culture, and was performed in the years from 1979 to 1981. Using the original VIP as the reference standard, the sensitivity rate of the EIA was 0.7674 and the false negative rate was 0.2326. However, when the storage age and the initial virus titer of the sample were considered, the sensitivity ...
Parreira DR, Jansen AM, Abreu UG, Macedo GC, Silva AR, Mazur C, Andrade GB, Herrera HM.Equine infectious anemia virus (EIAV) and Trypanossoma evansi are endemic in Brazilian Pantanal Biome, an important area for livestock production. In this sense, we evaluated the epidemiological single and co-infection effects of T. evansi and EIAV in naturally infected horses in the southern Pantanal wetland by serological tests and hematological assays. Both higher seroprevalence and heath poor condition of the sampled animals were associated with differences in horse management between farms. We found that the negative animals for both infectious agents (NN) represented the major group in F...
Patel JR, Bateman H, Williams J, Didlick S.A German abortion isolate of EHV-1 (strain M8) was grown in equine dermal (ED) cells at a low multiplicity of infection in presence of 5-bromo-2-deoxy uridine. The resulting stock was dialysed, titrated and cloned by terminal dilution in ED cells grown in 96-well microtitration plates. Of 192 clones each originating from a single focus, clone 147 (C147) was found to be restricted for growth at and above temperatures of 38.5 degrees C. It was also restricted for growth at 37 degrees C in rabbit kidney (RK-13) cells which are widely used for the isolation and titration of EHV-1; hence clone 147 ...
Katz JB, Evans LE, Hutto DL, Schroeder-Tucker LC, Carew AM, Donahue JM, Hirsh DC.To characterize clinical, serologic, bacteriologic, cytologic, and pathologic endometrial responses of mares to 2 donkey-origin atypical bacterial isolates resembling Taylorella equigenitalis. Methods: Prospective in vivo study. Methods: 10 healthy mares. Methods: Mares in estrus (2/group) were inoculated by intrauterine infusion with 2 isolates of classic T equigenitalis or 2 isolates of atypical Taylorella sp or were sham-inoculated. Bacteriologic, serologic, clinical, uterine, cytologic, and pathologic endometrial responses were assessed 4, 11, 21, 35, and 63 days after inoculation and on d...
Dunowska M, Howe L, Hanlon D, Stevenson M.The significance of infection with Equid herpesvirus 2 (EHV-2) remains unresolved, mainly due to its widespread distribution, and frequent isolation of the virus not only from diseased animals, but also from clinically normal horses. It has been suggested that EHV-2 exerts its effects on the host indirectly, through predisposition to secondary infections. The aim of this study was to determine kinetics of EHV-2 infection among foals and to investigate the role that EHV-2 may play in development of Rhodococcus equi pneumonia on one farm. Serial blood samples were collected from 43 foals over a ...
Zevenhoven-Dobbe JC, Greve S, van Tol H, Spaan WJM, Snijder EJ.Equine arteritis virus (EAV) contains seven structural proteins that are all required to produce infectious progeny. Alphavirus-based expression vectors have been generated for each of these proteins to explore the possibilities for their constitutive expression in cell lines. This approach was successful for minor glycoproteins GP(2b), GP(3) and GP(4) and for the E protein. Subsequently, it was demonstrated that cell lines expressing these proteins could rescue EAV mutants that were disabled in the expression of the corresponding gene, resulting in the production of virus particles carrying t...
Mumford EL, Traub-Dargatz JL, Carman J, Callan RJ, Collins JK, Goltz KL, Romm SR, Tarr SF, Salman MD.Horses vaccinated against common agents of infectious upper respiratory disease (IURD) may not have detectable serum antibody and may not be protected from clinical disease. Objective: The objectives of this study were to 1) investigate the serological response of horses to vaccination against influenza virus (H3N8 and H7N7) and equine herpesviruses (EHV) in a field setting and 2) evaluate associations among vaccination status, serum antibody concentrations, and occurrences of IURD in monitored horses. Methods: In this study, horses on 6 Colorado premises were vaccinated parenterally against i...
Lawrence GL, Gilkerson J, Love DN, Sabine M, Whalley JM.Sets of primers were designed which enabled specific amplification of homologous regions of the glycoprotein C and gene 76 genetic loci of equine herpesviruses 1 and 4 (EHV-1 and EHV-4). The resultant virus-specific polymerase chain reaction (PCR) products arising from each loci could be discriminated easily on the basis of size on an agarose gel, allowing rapid differentiation of the two equine herpesviruses. Specificity of the amplifications were confirmed by Southern hybridization and restriction endonuclease digestion. The PCR test was applied to nasal swab samples from weanling foals and ...
Nasci RS, Berry RL, Restifo RA, Parsons MA, Smith GC, Martin DA.During August and September of 1991, an epizootic of eastern equine encephalitis (EEE) virus in horses occurred in Wayne and Holmes countries, OH. This was the first recorded epizootic of EEE virus in the state. Twelve horses were confirmed positive for EEE virus through virus isolation or seroconversion, and seven additional horses with compatible symptoms were in close spatial and temporal proximity to the confirmed cases and were presumed to have died from EEE virus. The outbreak was centered around the Killbuck Wildlife Area, a 2,147-ha tract maintained by the state, half of which consists...
May JP, Walker CA, Maskell DJ, Slater JD.Streptococcus equi subsp. equi is the causative agent of the equine disease strangles. In this study we describe the development of an in vivo Himar1 transposon system for the random mutagenesis of S. equi and, potentially, other Gram-positive bacteria. We demonstrate efficient and random transposition of a modified mini-transposon onto the chromosome by Southern blot analysis and insertion site sequencing. Non-haemolytic mutants were isolated at a frequency of 0.2%, and acapsular mutants at a frequency of 0.04%. Taken together, these data demonstrate that in vivo Himar1 mutagenesis can be use...
Becher AM, Mahling M, Nielsen MK, Pfister K.For 9 consecutive months (March-November 2008), faecal samples were collected monthly from 129 horses residing within 40 km of Salzburg, Austria. Samples were analysed quantitatively using a modified McMaster egg counting technique. Whenever a faecal egg count (FEC) result exceeded 250 eggs per gram (EPG), the horse was treated with pyrantel, ivermectin or moxidectin. In 52 of 129 horses (40.3%), no strongyle eggs were ever detected over the course of 9 months. In 39 horses (30.2%), strongyle eggs were detected in at least 1 sample, but the egg count never exceeded 250 EPG. The remaining 38 (2...
Ntafis V, Fragkiadaki E, Xylouri E, Omirou A, Lavazza A, Martella V.Severe outbreaks of diarrhoeic syndrome occurred in young foals at the same stud farm during two consecutive breeding periods namely spring 2006 and 2007. Rotavirus-like particles were detected by electron microscopy in the faeces of the affected foals and group A rotavirus infection was confirmed by Reverse-Transcription (RT)-PCR with selected sets of rotavirus-specific primers. Sequence analysis of the genes encoding the outer capsid rotavirus proteins VP7 and VP4 enabled classification of the viruses as G3AP[12] and revealed that the viruses were highly similar to recently reported equine r...
Franzén P, Berg AL, Aspan A, Gunnarsson A, Pringle J.A 19-year-old horse that was one of a group of six horses infected experimentally with Anaplasma phagocytophilum for a study of the pathogenesis of equine granulocytic ehrlichiosis died suddenly two days after first showing clinical signs of disease. The clinical signs and laboratory findings observed before its death were similar to all those of the other infected horses, and to previous reports of this disease. A postmortem examination revealed widespread haemorrhaging in its internal organs, and vasculitis and thrombosis in the kidneys. These changes are consistent with disseminated intrava...
Howell PG, Nurton JP, Nel D, Lourens CW, Guthrie AJ.Cohorts of yearlings were sampled over a period of 6 years in a retrospective serological survey to establish the annual prevalence of serotype specific antibody to equine encephalosis virus on Thoroughbred stud farms distributed within defined geographical regions of South Africa. Seasonal seroprevalence varied between 3.6% and 34.7%, revealing both single and multiple serotype infections in an individual yearling. During the course of this study serotypes 1 and 6 were most frequently and extensively identified while the remaining serotypes 2, 3, 4, 5 and 7 were all identified as sporadic and...
Gallhoefer NS, Spiess BM, Guscetti F, Hilbe M, Hartnack S, Hafezi F, Pot SA.CXL penetration depth is an important variable influencing clinical treatment effect and safety. The purposes of this study were to determine the penetration depth of CXL in rabbit and equine corneas in epithelium-on and epithelium-off procedures and to assess an ex vivo fluorescent biomarker staining assay for objective assessment of CXL penetration depth. Methods: CXL treatment was performed according to a standardized protocol on 21 and 17 rabbit eyes and on 12 and 10 equine eyes with and without debridement, respectively. Control corneas were treated similarly, but not exposed to CXL. Hem...
Fall M, Fall AG, Seck MT, Bouyer J, Diarra M, Balenghien T, Garros C, Bakhoum MT, Faye O, Baldet T, Gimonneau G.Culicoides biting midges (Diptera: Ceratopogonidae) are important vectors of arboviruses in Africa. Culicoides oxystoma has been recently recorded in the Niayes region of Senegal (West Africa) and its high abundance on horses suggests a potential implication in the transmission of the African horse sickness virus in this region. This species is also suspected to transmit bluetongue virus to imported breeds of sheep. Little information is available on the biology and ecology of Culicoides in Africa. Therefore, understanding the circadian host-seeking activity of this putative vector is of prima...
Goehring LS, Soboll Hussey G, Gomez Diez M, Benedict K, Maxwell LK, Morley PS, Sloet van Oldruitenborgh-Oosterbaan MM, Lunn DP.Central nervous system blood vessel thrombosis is a part of the pathogenesis of equid herpesvirus-associated myeloencephalopathy (EHM). D-dimers (DD) are stable breakdown products of cross-linked fibrin, and increased DD-plasma concentrations could reflect the degree of systemic coagulation during EHV-1 infection. Objective: We hypothesized that blood DD concentrations will be increased during periods of EHV-1 fever and viremia, reflecting an activated coagulation cascade with fibrinolysis. Methods: Twenty-eight equids were infected with EHV-1 in 3 experimental infection studies. Three (uninfe...
Ribeiro MJ, Rosa MH, Bruhn FR, Garcia Ade M, Rocha CM, Guimarães AM.The present study used the indirect fluorescent antibody test (IFAT) to determine the seroprevalence of Sarcocystis neurona, Toxoplasma gondii and Neospora spp., and evaluated the variables associated with these infections among 506 apparently healthy horses, reared in the south of the state of Minas Gerais, Brazil. This study was conducted between April 2012 and October 2013. Among the horses, the true prevalence of S. neurona was 26% (95% CI: 22.0-30.4%), T. gondii 19.9% (95% CI: 15.5-24.8%) and Neospora spp. 23.9% (95% CI: 19.9-28.1%); and among the farms, 88.3% (95% CI: 74.4-91.6%), 71.6% ...
Hamond C, Pinna A, Martins G, Lilenbaum W.Leptospirosis is a zoonotic disease of global importance and has a worldwide distribution. This infection displays clear seasonal nature in some regions of the tropics, where the rainy season is marked by high temperatures. Household and wild animals carry leptospires and contribute to their dissemination in nature. Transmission mainly occurs by contact with water contaminated with the urine of infected animals, and consequently, it is quite widespread especially in times of rain, since many areas are subject to flooding and have poor sanitation. Serological tests demonstrate that Leptospira s...
Rota A, Calicchio E, Nardoni S, Fratini F, Ebani VV, Sgorbini M, Panzani D, Camillo F, Mancianti F.A saprophytic bacterial flora is present on the penis and the distal part of the urethra of stallions. Little is known about the fungal flora of their reproductive tract. As micro organisms play an important role in mares fertility, the aim of the study was to describe the distribution of fungi and bacteria in the normal genital apparatus of stallions. The microbic flora of the reproductive tract of 11 healthy, fertile stallions was evaluated, collecting samples from 5 different locations: urethral fossa, penis/internal lamina of the prepuce, urethra pre- and post-ejaculation, and semen. For f...
Pusterla N, Barnum S, Lawton K, Wademan C, Corbin R, Hodzic E.Contemporary data on equine herpesvirus-1 (EHV-1) genotype (non-neuropathogenic or N, neuropathogenic or D and new variant or H) in clinically diseased equids is important in order to determine the frequency of these genotypes and their association with disease expression. A total of 297 EHV-1 qPCR-positive swabs collected from 2019 to 2022 from horses with respiratory disease (EHV-1), neurological disease (equine herpesvirus-1 myeloencephalopathy [EHM]) and abortion were tested for the three different EHV-1 genotypes (N, D and H) using qPCR allelic discrimination assays. All submissions origi...
Kooijman LJ, Mapes SM, Pusterla N.Equine coronavirus (EqCoV) infection has been documented in most reports through quantitative qPCR analysis of feces and viral genome sequencing. Although qPCR is used to detect antigen during the acute disease phase, there is no equine-specific antibody test available to study EqCoV seroprevalence in various horse populations. We developed an enzyme-linked immunosorbent assay (ELISA) targeting antibodies to the spike (S) protein of EqCoV and validated its use, using acute and convalescent sera from 83 adult horses involved in 6 outbreaks. The EqCoV S protein-based ELISA was able to reliably d...
Equine infectious anemia (EIA) is a viral disease, caused by the Equine Infectious Anemia virus (EIAV) belonging to the Retroviridae family, genus Lentivirus. Horses (or equids) infected with EIAV are lifelong carriers and they remain contagious for other horses even in the absence of clinical signs. So far, EIAV infection has been reported among horses in North and South America, France, Germany, Italy, Hungary and Romania, with no publication regarding the presence of EIAV in horses in Serbia. To determine the circulation of EIAV among, approximately, the 5000 horses of the Vojvodina region,...
Furrer E, Bilzer T, Stitz L, Planz O.Experimental Borna disease virus (BDV) infection of rats and natural infection of horses and sheep leads to severe central nervous system disease based on immunopathological pathways. The virus replicates slowly, and the cellular immune response results in immunopathology. CD8(+) T cells exert effector cell functions, and their activity results in the destruction of virus-infected cells. Previously, Oldach and colleagues (D. Oldach, M. C. Zink, J. M. Pyper, S. Herzog, R. Rott, O. Narayan, and J. E. Clements, Virology 206:426-434, 1995) have reported protection against Borna disease after inocu...
Bryant UK, Lyons ET, Bain FT, Hong CB.A 13-week-old Thoroughbred colt from central Kentucky was euthanized after an acute onset of ataxia, blindness, head tremors, leaning to the right, recumbency, and seizures. Microscopically, there was a verminous meningoencephalitis characterized by an eosinophilic and granulomatous inflammatory reaction primarily affecting the cerebellum. Dispersed within regions of inflammation were numerous cross and longitudinal sections of intact and degenerative small nematodes. The nematodes had dorsoflexed ovaries and ventroflexed vulvas, which are distinguishing features of Halicephalobus gingivalis. ...
Kumar K, Arshad SS, Selvarajah GT, Abu J, Toung OP, Abba Y, Yasmin AR, Bande F, Sharma R, Ong BL.Japanese encephalitis (JE) is a vector-borne zoonotic disease caused by the Japanese encephalitis virus (JEV). It causes encephalitis in human and horses, and may lead to reproductive failure in sows. The first human encephalitis case in Malaya (now Malaysia) was reported during World War II in a British prison in 1942. Later, encephalitis was observed among race horses in Singapore. In 1951, the first JEV was isolated from the brain of an encephalitis patient. The true storyline of JE exposure among humans and animals has not been documented in Malaysia. In some places such as Sarawak, JEV ha...
Jemmerson R, Margoliash E.Seven populations of site-specific antibodies were isolated from each of three sera of rabbits immunized against glutaraldehyde-polymerized horse cytochrome c. The antibodies were separated using an immunoadsorption scheme which employed the following cytochromes c: horse, beef, guanaco, rabbit, mouse testicular, pigeon, and the cyanogen-bromide cleaved fragment of the rabbit protein containing residues 1 to 65. The monovalent, antigen-binding fragments of the antibodies (Fab') gave 1:1 stoichiometries with native horse cytochrome c in fluorescence quenching assays. Cross-reactivities with het...
Traversa D, Kuzmina T, Kharchenko VA, Iorio R, Klei TR, Otranto D.This study investigated the genetic variability within Cylicocyclus nassatus (Nematoda, Strongylida, Cyathostominae) collected from different domestic and wild hosts (i.e. horse, donkey, Przewalskii horse, tarpan and Turkmen kulan) and localities in Europe and/or USA. The ribosomal Internal Transcribed Spacer 2 (ITS2) and the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene were PCR-amplified and sequences characterized from seventy individual parasitic specimens. While ITS2 displayed 0-0.6% variation rate among all individual adult specimens of C. nassatus examined, 22 different seque...
