Serology in horse research involves the study and analysis of blood serum to detect the presence of antibodies or antigens associated with infectious diseases and other health conditions. It is a diagnostic tool used to identify immune responses to pathogens, vaccination status, and exposure to specific diseases. Serological tests in equine research can include enzyme-linked immunosorbent assays (ELISA), complement fixation tests, and virus neutralization tests. These tests help in understanding the epidemiology of diseases, monitoring herd health, and informing vaccination strategies. This page compiles peer-reviewed research studies and scholarly articles that explore the methodologies, applications, and implications of serological testing in equine medicine.
The National Reference Center for equine infectious anemia (EIA) validated a commercial ELISA (Eradikit EIAV Indirect ELISA, In3diagnostic, Turin, Italy) employing a chimeric recombinant gag and env peptide for the detection of EIA virus antibodies, following the guidelines of the World Organization for Animal Health. The validation parameters evaluated were: analytical sensitivity (Se) and specificity (Sp); diagnostic Se and Sp; precision, based on repeatability and reproducibility through the estimation of the standard deviation (SD) and the coefficient of variation (CV); accuracy, estimated...
Rocheleau JP, Michel P, Lindsay LR, Drebot M, Dibernardo A, Ogden NH, Fortin A, Arsenault J.Periodic outbreaks of West Nile virus (WNV), Eastern equine encephalitis virus (EEEV) and to a lesser extent, California serogroup viruses (CSGV), have been reported in parts of Canada in the last decade. This study was designed to provide a broad assessment of arboviral activity in Quebec, Canada, by conducting serological surveys for these arboviruses in 196 horses, 1442 dogs and 485 humans. Sera were screened by a competitive enzyme linked immunosorbent assay and positive samples confirmed by plaque reduction neutralisation tests. The percentage of seropositive samples was 83·7%, 16·5%, 7...
Beck C, Lowenski S, Durand B, Bahuon C, Zientara S, Lecollinet S.West Nile Fever is a zoonotic disease caused by a mosquito-borne flavivirus, WNV. By its clinical sensitivity to the disease, the horse is a useful sentinel of infection. Because of the virus' low-level, short-term viraemia in horses, the primary tools used to diagnose WNV are serological tests. Inter-laboratory proficiency tests (ILPTs) were held in 2010 and 2013 to evaluate WNV serological diagnostic tools suited for the European network of National Reference Laboratories (NRLs) for equine diseases. These ILPTs were designed to evaluate the laboratories' and methods' performances in detectin...
Pavulraj S, Virmani N, Bera BC, Joshi A, Anand T, Virmani M, Singh R, Singh RK, Tripathi BN.Equine influenza viruses (EIVs) are responsible for acute contagious respiratory infection in equines and the disease remains a major threat for equine population throughout the world despite vaccination strategies in place. The present study was aimed to assess the suitability of BALB/c mice as a potential small animal model for preliminary screening of EI vaccine candidates. For this, we evaluated the immunogenicity and protective efficacy of an inactivated EIV (H3N8) vaccine in BALB/c mouse model after challenge with homologous H3N8 virus (Clade 2 virus, Florida sublineage) through serology...
Malalana F, Blundell RJ, Pinchbeck GL, Mcgowan CM.Equine recurrent uveitis (ERU) is a common cause of ocular pain and blindness in horses. Leptospira spp. have been commonly implicated in the pathophysiology of ERU in mainland Europe and the USA. No recent studies have been carried out in the UK, but Leptospira is reported not to be a major factor in the aetiology of ERU in the UK. Objective: To establish the prevalence of Leptospira-associated ERU in the UK and to identify the serovars involved in these cases; to compare serum vs. aqueous humour antibody levels in cases and controls in order to confirm the diagnosis of Leptospira-associated ...
ELISAs are known to have a higher diagnostic sensitivity than the agar gel immunodiffusion (AGID) when employed for serological diagnosis of equine infectious anaemia (EIA). For this purpose, an "in-house" and five commercial ELISAs available in Italy were assessed by the National Reference Centre for EIA for their analytic specificity (Sp); precocity, defined as capability of detecting first antibodies produced during a new infection; precision based on repeatability and reproducibility, estimated from the coefficient of variation (CV); accuracy, estimated from multiple K and relative Sp and ...
Becker E, Venter GJ, Greyling T, Molini U, van Hamburg H.Equine mortalities suspected to be due to African horse sickness (AHS) were reported from the arid Khomas Region, Namibia, in 2008. The area was previously considered a localized AHS-free area. Hartmann's mountain zebra (Equus zebra hartmannae), a potential but unconfirmed reservoir host of African horse sickness virus (AHSV), occurs in the region. Between 2009 and 2010 serum, blood and tissue samples from 31 culled E. z. hartmannae were analysed by reverse transcription-polymerase chain reaction (RT-PCR) (n = 31) and enzyme-linked immunosorbent assay (ELISA) (n = 18) to determine the p...
Venturi SS, da Silva AF, Frazão-Teixeira E, de Oliveira FCR, Consalter A, Padilha FGF, Fonseca ABM, Ferreira AMR.The aim of this study was to perform a survey on the prevalence of anti-Toxoplasma gondii antibodies in horses from Rio de Janeiro State, Brazil. From 2012 to 2013, a total of 624 blood samples were collected from horses from the eight regions comprising Rio de Janeiro State (Baixadas Litorâneas, Serrana, Norte Fluminense, Noroeste Fluminense, Centro-Sul, Metropolitana, Médio Paraíba, and Costa Verde). All sera samples were tested for anti-T. gondii antibodies by performing the modified agglutination test with a cut-off of 1:25. Positive serology for T. gondii was detected in 22.8% (142/624...
Portella LP, Cadore GC, Sangioni LA, Pellegrini LF, Fighera R, Ramos F, Vogel FS.Sarcocystis spp., Neospora spp., and Toxoplasma gondii are Apicomplexa protozoa that can infect horses. This study aimed to investigate the occurrence of antibodies against Sarcocystis spp., Neospora spp., and T. gondii in horses slaughtered in southern Brazil. The presence of histological lesions, tissue cysts, and Sarcocystis spp. DNA in the hearts of these horses was also investigated. A total of 197 paired serum and heart samples were evaluated by serology and direct microscopic examination; 50 of these samples were subjected to histopathological and PCR analyses. Antibodies against at lea...
Oliveira FG, Cook RF, Naves JHF, Oliveira CHS, Diniz RS, Freitas FJC, Lima JM, Sakamoto SM, Leite RC, Issel CJ, Reis JKP.Equine infectious anemia virus (EIAV) is an important cause of morbidity and mortality throughout the world. Although the virus infects all members of the Equidae the vast majority of studies have been conducted in horses (Equus caballus) with comparatively little information available for other equid species. Brazil has one of the most abundant donkey (E. asinus) populations of any nation although the economic importance of these animals is declining as transportation becomes increasingly mechanized. As a result, considerable numbers of donkeys especially in the Northeast of the country have ...
Lopez KM, Fleming GJ, Mylniczenko ND.Reports of equine herpesvirus (EHV) 1 and EHV-9 causing clinical disease in a wide range of species have been well documented in the literature. It is thought that zebras are the natural hosts of EHV-9 both in the wild and in captive collections. Concerns about potential interspecies transmission of EHV-1 and EHV-9 in a mixed species savannah exhibit prompted serologic and polymerase chain reaction surveys. Eighteen Burchell's zebras ( Equus quagga ), 11 Hartmann's mountain zebras ( Equus zebra hartmannae), and 14 Thomson's gazelles ( Eudorcas thomsonii ) cohabitating the same exhibit were exa...
Pinto PS, Libonati H, Lilenbaum W.Leptospirosis is a worldwide zoonosis which can affect many species. Control programs need accurate diagnosis to be successful, and currently, diagnosis relies on serology. It presents three main issues: the sampling, the antigen panel, and the cutoff point. Herein, we propose a systematic review on leptospirosis among dogs, pigs, and horses in Latin America in order to improve the understanding of the seroepidemiology of leptospirosis in these species in the region as well as the temporal development of the research on this topic and, consequently, improve the chances of success on control pr...
Joó K, Bakonyi T, Szenci O, Sárdi S, Ferenczi E, Barna M, Malik P, Hubalek Z, Fehér O, Kutasi O.West Nile virus (WNV) mainly infects birds, horses and humans. Outcomes of the infection range from mild uncharacteristic signs to fatal neurologic disease. The main objectives of the present study were to measure serum IgG and IgM antibodies in naturally exposed and vaccinated horses and to compare results of haemagglutination inhibition test (HIT), enzyme-linked immunosorbent assay (ELISA) and plaque reduction neutralisation test (PRNT). Altogether 224 animals were tested by HIT for WNV antibodies and 41 horses were simultaneously examined by ELISA and PRNT. After primary screening for WNV a...
Adney DR, Brown VR, Porter SM, Bielefeldt-Ohmann H, Hartwig AE, Bowen RA.The Middle East respiratory syndrome coronavirus (MERS-CoV) was first recognized in 2012 and can cause severe disease in infected humans. Dromedary camels are the reservoir for the virus, although, other than nasal discharge, these animals do not display any overt clinical disease. Data from in vitro experiments suggest that other livestock such as sheep, goats, and horses might also contribute to viral transmission, although field data has not identified any seropositive animals. In order to understand if these animals could be infected, we challenged young goats and horses and adult sheep wi...
Tirosh-Levy S, Blum SE, Steward KF, Waller AS, Steinman A.The purpose of this cross-sectional study was to determine the seroprevalence of Streptococcus equi in Israel, to monitor seropositive horses over time and to identify archived strains that were recovered from Israeli horses. A serological survey of 200 healthy horses on 20 farms throughout Israel was performed to detect recent exposure to S equi antigens A and C via indirect ELISA. Seroprevalence was 9.5 per cent (19/200) and positive horses were found in 30 per cent (6/20) of the farms. Sixteen horses that returned a positive serology result were retested three and six months later. Most (12...
Harvey AM, Watson JL, Brault SA, Edman JM, Moore SM, Kass PH, Wilson WD.OBJECTIVE To investigate the impact of age and inferred prior vaccination history on the persistence of vaccine-induced antibody against rabies in horses. DESIGN Serologic response evaluation. ANIMALS 48 horses with an undocumented vaccination history. PROCEDURES Horses were vaccinated against rabies once. Blood samples were collected prior to vaccination, 3 to 7 weeks after vaccination, and at 6-month intervals for 2 to 3 years. Serum rabies virus-neutralizing antibody (RVNA) values were measured. An RVNA value of ≥ 0.5 U/mL was used to define a predicted protective immune response on the b...
Gather T, Walter S, Todt D, Pfaender S, Brown RJP, Postel A, Becher P, Moritz A, Hansmann F, Baumgaertner W, Feige K, Steinmann E, Cavalleri JV.Non-primate hepacivirus (NPHV), a recently discovered hepatotropic virus infecting horses, is phylogenetically the closest known homologue of hepatitis C virus (HCV). The main route for acquiring HCV infection in childhood is vertical transmission. However, nothing is known about the natural mode of transmission for NPHV. To investigate the possibility of vertically transmitted NPHV infection in horses, 20 Thoroughbred broodmares and their foals were monitored during foaling season 2015 until 6 months post-partum. Prepartal serum was taken from the mares, and during foaling umbilical cord bloo...
Sant C, d'Abadie R, Pargass I, Basu AK, Asgarali Z, Charles RA, Georges KC.Equine piroplasmosis caused by Theileria equi and Babesia caballi is endemic in Trinidad and Tobago. Transmission occurs by ticks of the family Ixodidae. T. equi can also be transmitted transplacentally; however transplacental transmission of B. caballi is unknown. This study aims to investigate transplacental transmission of equine piroplasmosis from thoroughbred mares naturally infected via the tick vector. Whole blood and serum samples were collected from 117 mares in the fifth month of pregnancy. Blood samples were also collected from each of their foals (89 in total) within the first 36h ...
Tagliabue S, Figarolli BM, D'Incau M, Foschi G, Gennero MS, Giordani R, Giordani R, Natale A, Papa P, Ponti N, Scaltrito D, Spadari L, Vesco G....Nowadays, leptospirosis is a re‑emerging widespread infectious disease often underestimate worldwide. The National Reference Centre for Leptospirosis (NRCL), at the Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Brescia (Italy), with the cooperation of all the other Istituti Zooprofilattici Sperimentali (IIZZSS), evaluated the distribution of such important zoonosis in Italy. Serological data obtained between 2010‑2011 by each laboratory were collected by the NRCL and discussed. Serum samples collected from 43,935 animal specimens were analysed by the Microsco...
Johnstone LK, Engiles JB, Aceto H, Buechner-Maxwell V, Divers T, Gardner R, Levine R, Scherrer N, Tewari D, Tomlinson J, Johnson AL.Equine neuroborreliosis (NB), Lyme disease, is difficult to diagnose and has limited description in the literature. Objective: Provide a detailed description of clinical signs, diagnostic, and pathologic findings of horses with NB. Methods: Sixteen horses with histologically confirmed NB. Methods: Retrospective review of medical records at the University of Pennsylvania and via an ACVIM listserv query with inclusion criteria requiring possible exposure to Borrelia burgdorferi and histologic findings consistent with previous reports of NB without evidence of other disease. Results: Sixteen hors...
Lee H, Kim EJ, Cho IS, Song JY, Choi JS, Lee JY, Shin YK.Severe fever with thrombocytopenia syndrome (SFTS) is caused by the SFTS virus (SFTSV). The SFTSV appears to have a wide host range, as SFTSV-positive ticks have been isolated from both farm animals and wild rodents. Therefore, it is important to monitor SFTSV-positive animals to prevent the transmission of SFTSV from animals to humans. Previously, we developed a competitive enzyme-linked immunosorbent assay (cELISA) to detect SFTSV-specific antibodies from field animals and compared the cELISA results to those from an indirect immunofluorescence assay (IFA). In this study, cELISA results were...
Lightbody KL, Davis PJ, Austin CJ.Tapeworm infections pose a significant threat to equine health as they are associated with clinical cases of colic. Diagnosis of tapeworm burden using fecal egg counts (FECs) is unreliable, and, although a commercial serologic ELISA for anti-tapeworm antibodies is available, it requires a veterinarian to collect the blood sample. A reliable diagnostic test using an owner-accessible sample such as saliva could provide a cost-effective alternative for tapeworm testing in horses, and allow targeted deworming strategies. Objective: The purpose of the study was to statistically validate a saliva ta...
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...
Abrahão JS, de Souza Trindade G, Pereira-Oliveira G, de Oliveira Figueiredo P, Costa G, Moreira Franco-Luiz AP, Lopes Assis F, Bretas de Oliveira D....In August 2014, an outbreak of oral exanthematous disease in equids was reported in Brazil, affecting 11 donkeys and 3 mules. Objective: To investigate if Vaccinia virus (VACV) was the aetiological agent in this outbreak. Methods: Investigation of clinical cases using serological, molecular and phylogenetic approaches. Methods: To analyse the presence of neutralising antibodies against VACV, samples were submitted in triplicate to a plaque-reduction neutralisation test (PRNT ). On the basis of previous studies which detected VACV DNA in sera, we submitted extracted DNA samples to different pol...
Nardini R, Autorino GL, Ricci I, Frontoso R, Rosone F, Simula M, Scicluna MT.The Italian National Reference Center for equine infectious anemia (CRAIE; Rome, Italy) developed and validated a monoclonal, recombinant p26-based competitive enzyme-linked immunosorbent assay (cELISA) for the detection of EIA virus antibodies employing the 2010 criteria of the World Organization for Animal Health (OIE). The following parameters were evaluated: cutoff values, repeatability, reproducibility, concordance, analytical sensitivity (Se), absolute analytical specificity (Sp), and diagnostic Se and Sp. Positive and negative predictive values were also defined in relation to the estim...
Ricotti S, Garcia MI, Veaute C, Bailat A, Lucca E, Cook RF, Cook SJ, Soutullo A.Molecular and serological techniques for Equine Infectious Anemia Virus (EIAV) diagnosis were compared using samples from 59 clinically normal horses stabled on five farms in the Santa Fe Province of Argentina. Of these 26 (44.1%) were positive in official AGID tests and/or gp45/gp90-based ELISA. Surprisingly 18 of the 33 seronegative horses were positive in a PCR against viral sequences encoding gp45 (PCR-positive/AGID-negative) with all but one remaining EIAV-antibody negative throughout a two year observation period. The gp45 PCR results are supported by fact that 7/18 of these horses were ...
Kinsley R, Scott SD, Daly JM.Serological assays provide an indirect route for the recognition of infectious agents via the detection of antibodies against the infectious agent of interest within serum. Serological assays for equine influenza A virus can be applied for different purposes: diagnosing infections; subtyping isolates; surveillance of circulating strains; and to evaluate the efficacy of vaccines before they reach the market. Haemagglutination inhibition (HI) and single radial haemolysis (SRH) assays are most commonly used in the equine field. This review outlines how both these assays together with virus neutra...
Durand B, Haskouri H, Lowenski S, Vachiery N, Beck C, Lecollinet S.A serosurvey of 349 military working horses and 231 military working dogs was conducted in ten sites in Morocco in 2012. This survey revealed a high level of exposure of these animals to flaviviruses: seroprevalence rates of 60% in horses and of 62% in dogs were observed using a competitive West Nile virus (WNV) enzyme-linked immunosorbent assay (cELISA). Seroneutralization test results showed that the majority of cELISA-positive results were due to exposure to WNV. Further assays conducted in vaccinated horses with a DIVA (Differentiating Infected from Vaccinated Animals) test indicated that ...
Kang BK, Hwang JM, Moon H, Han SY, Kim JM, Yang DK, Park BK, Song D.The Japanese encephalitis virus (JEV) genotype circulating in Korea has changed from G3 to G1. Therefore, the purpose of this study was to compare the antigenic relationship between the two genotypes by using antibody tests. Methods: Blood samples from 42 sows and 216 horses were collected, and their seroprevalence was monitored using the hemagglutination inhibition and virus neutralization tests. Antisera against JEV G1 and G3 were isolated and prepared from guinea pigs. The cross-reactivity of these two viruses was then compared using the neutralizing antibody test. Results: We found that th...
Sumbria D, Singla LD, Kumar S, Sharma A, Dahiya RK, Setia R.Equine piroplasmosis is a febrile, tick-borne disease of equids predominately caused by obligatory intra-erythrocytic protozoa Theileria equi in the Indian sub-continent. A cross-sectional study was carried out on 464 equids (426 horses and 38 donkeys/mules) in Punjab, India to assess the level of exposure to equine piroplasmosis by 18S rRNA gene nested polymerase chain reaction (nPCR) and equine merozoite antigen-2 (EMA2) indirect-ELISA (enzyme linked immunosorbent assay), to investigate risk factors and haemato-biochemical alterations associated with the infection. The endemicity of the dise...
Sentsui H, Kono Y.During the autumn of 1978 a disease characterised by fever and occasionally by exanthema and/or oedema of the limbs was seen in approximately 13 per cent of horses in a training stable in the Kanto district of Japan. A virus was isolated by the intracerebral inoculation of one-day-old mice from blood and nasal swabs taken from naturally and experimentally infected horses. The virus was subsequently passaged in two monkey kidney cell lines in which it produced complete cytopathic changes. Infected horses developed neutralising, complement fixing and haemagglutinin inhibiting antibodies to the v...
Pusterla N, Lutz H, Braun U.Four clinically healthy horses which were negative for antibodies to Ehrlichia phagocytophila, the agent of bovine ehrlichiosis, were infected experimentally with E phagocytophila-containing bovine leucocytes, administered intravenously. The horses were examined daily for four weeks, and blood samples were collected daily for cytological, haematological and biochemical examination and for a nested polymerase chain reaction (PCR). An indirect immunofluorescence test was used to determine when the horses seroconverted and the duration of positive titres. There were no abnormal clinical, haematol...
Guimarães-Ladeira CV, Palhares MS, Oliveira JS, Ramirez MA, Guedes RM.Proliferative enteropathy, caused by the intracellular bacterium Lawsonia intracellularis, has been described in horses in Australia, the USA, Canada and European countries but has not been reported in Latin America. The prevalence of the disease in horses worldwide is unknown. Objective: To evaluate the presence of subclinical L. intracellularis infection in horses in the state of Minas Gerais, Brazil. Methods: A longitudinal study using serology and PCR for detecting antibodies (IgG) and shedding of L. intracellularis in faecal samples, respectively, was conducted using a total of 223 horses...
Herr S, Huchzermeyer HF, Te Brugge LA, Williamson CC, Roos JA, Schiele GJ.The same techniques may be used in the complement fixation test (CFT) for the serological diagnosis of bovine brucellosis, Johne's disease (paratuberculosis), dourine, equine piroplasmosis and Q fever (caused by Coxiella burnetii). The reproducibility of results is excellent, falling for the most part within the twofold range and never exceeding the fourfold range. Agreement with other laboratories is excellent (i.e. within twofold) in the case of brucellosis and equine piroplasmosis antibody titres. A good correlation between the occurrence of the disease and serological reactions is found on...
Frey R, Bergvall K, Egenvall A.Insect bite hypersensitivity (IBH) and atopy can both be causes of pruritus in horses and are associated with allergen-specific IgE to biting insects and environmental allergens respectively. Information with respect to differences in IgE levels in diseased and healthy animals is crucial in enabling an understanding of the clinical relevance of results of allergen-specific IgE tests. The aim of this study was (i) to evaluate and compare levels of allergen-specific IgE, using an ELISA method, in Icelandic horses, with and without IBH, from Iceland and Sweden respectively; (ii) to investigate pa...
Motloang MY, Thekisoe OM, Alhassan A, Bakheit M, Motheo MP, Masangane FE, Thibedi ML, Inoue N, Igarashi I, Sugimoto C, Mbati PA.The prevalence of Theileria equi and Babesia caballi infections in the north-eastern Free State Province of South Africa was determined by examination of thin and thick Giemsa-stained blood smears, IFAT and PCR. No parasites were detected by microscopy from any blood samples collected at five study sites, Qwaqwa, Kestell, Harrismith, Vrede and Warden. Of the tested serum samples, 28/29 (96.5%), 20/21 (95.2%) and 42/42 (100%) were positive by IFAT for T. equi infections in Harrismith, Kestell and Qwaqwa, respectively, and 5/29 (17.2%), 13/21 (61.9%) and 30/42 (71.4%) were sero-positive for B. c...
Salvagni CA, Dagnone AS, Gomes TS, Mota JS, Andrade GM, Baldani CD, Machado RZ.Ehrlichiosis is a zoonotic disease caused by gram-negative and intracellular obligatory bacterial organisms. Equine Granulocytic Anaplasmosis - EGA (formerly Equine Granulocytic Ehrlichiosis, EGE) is a seasonal disease, normally self-limited in horses. There are few reports in Brazil about this ehrlichial agent, as well as its natural vectors. Nowadays, veterinarians are considering the suspicion of EGA in horses with suggestive symptoms of ehrlichiosis and which do not respond to piroplasmosis treatment. The aim of the present study was to identify horses exposed to the agent A. phagocytophil...
Wagner B, Goodman LB, Rollins A, Freer HS.Lyme disease is caused by Borrelia burgdorferi, which is transmitted by infected ticks (Ixodes spp.). Reports on Lyme disease in horses have increased in recent years. Nevertheless, the diagnosis of Lyme disease in horses is still challenging owing to its vague clinical presentation and the limitations of diagnostic tests. Objective: This study used a new serological Lyme multiplex assay to examine antibody responses to 3 antigens of B. burgdorferi, outer surface protein (Osp) C, OspF and C6, and to verify their use as markers for early and late infection stages in horses. Methods: Multiplex...
Hamond C, Martins G, Bremont S, Medeiros MA, Bourhy P, Lilenbaum W.A strain of Leptospira kirschneri (serogroup Grippotyphosa) was cultured from urine of a mare post-abortion in Brazil and characterized by serogrouping, multiple-locus variable-number tandem repeat analysis, PGFE, and sequencing of genes rrs and secY. Strains of L. kirschneri have apparently never been recovered from horses in tropical area, only in Europe and USA. Knowledge of local epidemiology is important to interpret genetic profiles of leptospires circulating in an area.
Kitai Y, Kondo T, Konishi E.A complement-dependent cytotoxicity (CDC) assay was established to measure antibodies to the West Nile virus (WNV) nonstructural protein 1 (NS1) in horses. Sera collected from a WNV-infected horse mediated lysis of WNV NS1-expressing cells in a dose-dependent manner at higher percentages than sera from a Japanese encephalitis virus (JEV)-infected horse. The percentages of specific lysis for sera diluted 1:10 to 1:80 were <19.8% (assay cutoff) for almost all of the 100 JEV-infected or uninfected horses tested, in contrast to 55 to 76% in WNV-infected horses. Experimental infection revealed t...
Johnson AL, Divers TJ, Chang YF.Confirmation of Borrelia burgdorferi infection in horses has required enzyme-linked immunosorbent assay (ELISA) or Western blot tests performed by reference laboratories. An in-clinic C6 ELISA SNAP kit has been marketed for dogs. This canine kit was evaluated for horses using serum from experimentally infected ponies. Serum samples originated from 2 previous studies. In the first study, 7 ponies were exposed to B. burgdorferi-infected ticks; 4 ponies served as uninfected controls. Serum samples were obtained bimonthly for 9 months. In the second study, 16 ponies were exposed to B. burgdorferi-...
Fischer NM, Favrot C, Birkmann K, Jackson M, Schwarzwald CC, Müller M, Tobler K, Geisseler M, Lange CE.The DNA of equine papillomavirus type 2 (EcPV2) is consistently found in equine papillomas and squamous cell carcinomas, indicating a causal association of EcPV2 in the pathogenesis of these tumours; however, little is known about the prevalence of this virus. Objective: The aim of this study was to determine the geno- and seroprevalence of EcPV2 in clinically healthy horses in Switzerland. Methods: Fifty horses presented to the equine department of the university clinic, displaying no skin or mucous membrane lesions or severe signs of other diseases, were sampled. Methods: Cytobrush samples ...
Balasuriya UB, Evermann JF, Hedges JF, McKeirnan AJ, Mitten JQ, Beyer JC, McCollum WH, Timoney PJ, MacLachlan NJ.A virus isolated from an aborted equine fetus was determined to be antigenically distinct from several other strains of equine arteritis virus (EAV) by use of a neutralization assay with a large panel of neutralizing monoclonal antibodies. The virus was readily neutralized by polyclonal equine anti-EAV serum. Comparative nucleotide and amino acid sequence analyses indicated that the virus (WA97) isolated from the aborted fetus was virtually identical to a virus (S1971) isolated from imported semen used to inseminate another mare on the farm. Phylogenetic analysis indicated that the WA97/S1971 ...
Albano AP, Klafke GB, Brandolt TM, Da Hora VP, Nogueira CE, Xavier MO, Meireles MC.Paracoccidioides brasiliensis is the etiological agent of the major systemic mycosis in Brazil, called paracoccidioidomycosis. Although the Rio Grande do Sul is considered an endemic area of the disease, there are few studies on the ecology of P. brasiliensis in the state. Therefore, this study aimed to evaluate the infection of P. brasiliensis in horses from the mesoregion of Southwest Riograndense, using these animals as sentinels. Serological techniques, such as double immunodiffusion in agar gel (AGID) and indirect ELISA, were performed to detect the anti-gp43 P. brasiliensis antibody in h...
Kinsley R, Scott SD, Daly JM.Serological assays provide an indirect route for the recognition of infectious agents via the detection of antibodies against the infectious agent of interest within serum. Serological assays for equine influenza A virus can be applied for different purposes: diagnosing infections; subtyping isolates; surveillance of circulating strains; and to evaluate the efficacy of vaccines before they reach the market. Haemagglutination inhibition (HI) and single radial haemolysis (SRH) assays are most commonly used in the equine field. This review outlines how both these assays together with virus neutra...
Diaz-Méndez A, Hewson J, Shewen P, Nagy E, Viel L.To develop a method for experimental induction of equine rhinitis A virus (ERAV) infection in equids and to determine the clinical characteristics of such infection. Methods: 8 ponies (age, 8 to 12 months) seronegative for antibodies against ERAV. PROCEDURES-Nebulization was used to administer ERAV (strain ERAV/ON/05; n = 4 ponies) or cell culture medium (control ponies; 4) into airways of ponies; 4 previously ERAV-inoculated ponies were reinoculated 1 year later. Physical examinations and pulmonary function testing were performed at various times for 21 days after ERAV or mock inoculation. Va...
Chambers TM, Shortridge KF, Li PH, Powell DG, Watkins KL.The Directigen FLU-A enzyme immunoassay was tested for its ability to detect equine-2 influenza viruses in nasopharyngeal fluids from horses and ponies. A total of 125 swabs from experimental infections and from different sources of natural infection in the USA and Hong Kong were examined. The assay results were compared with the results of standard virus culture in embryonated chicken eggs or Madin-Darby canine kidney cells, and with the serology of the horses sampled. In comparison with virus culture the enzyme immunoassay exhibited 83 per cent sensitivity, 78 per cent specificity, 70 per ce...
Qi T, Ai J, Sun Y, Ma H, Kang M, You X, Li J.Toxoplasmosis is a zoonotic disease caused by the obligate intracellular protozoan parasite which is widely prevalent in humans and animals worldwide. The diagnosis of toxoplasmosis and distinguishing acute or chronic infections have utmost importance for humans and animals. The SAG1, GRA7, and BAG1 proteins were used in the present study to develop the serological rSAG1-ELISA, rGRA7-ELISA and rBAG1-ELISA methods for the testing of specific IgG and IgM antibodies and differentiating acute or chronic toxoplasmosis in 3733 animals, including Tibetan sheep, yaks, pigs, cows, cattle, horses, ch...
Veronesi F, Laus F, Passamonti F, Tesei B, Piergili Fioretti D, Genchi C.The aim of the study was to investigate Borrelia burgdorferi sensu lato (s.l.) infection in horses exposed to heavy tick infestations. Blood samples of 98 healthy horses from 5 stud farms were examined by SNAP(®) 4D× and PCR to detect antibodies against B. burgdorferi s.l. and Borrelia DNA, respectively. Ten samples (15.3%) were antibody positive and 5 samples (5.1%) were both antibody and PCR positive. Sequence analysis showed the highest homology with the B. lusitaniae genospecies. No differences were found between sexes and stud farms, while age was significantly related to seropositivity...
DOLL ER, WALLACE E, RICHARDS MG.Manninger and Csontos reported that mares inoculated with equine abortion virus developed a transient fever 2 to 4 days after pharyngeal or intravenous inoculation and that an uninoculated horse in contact with the experimentally inoculated mares contracted a febrile disease resembling equine influenza. Also, mares that had aborted virus-infected fetuses were resistant to inoculation with equine influenza virus. From these observations, they proposed that virus abortions were a manifestation of infection of pregnant mares by the equine influenza virus. In reports on equine virus abortions, Kre...
Svoboda WK, Martins LC, Malanski Lde S, Shiozawa MM, Spohr KA, Hilst CL, Aguiar LM, Ludwig G, Passos Fde C, Silva LR, Headley SA, Navarro IT.Saint Louis encephalitis virus (SLEV) primarily occurs in the Americas and produces disease predominantly in humans. This study investigated the serological presence of SLEV in nonhuman primates and horses from southern Brazil. Methods: From June 2004 to December 2005, sera from 133 monkeys (Alouatta caraya, n=43; Sapajus nigritus, n=64; Sapajus cay, n=26) trap-captured at the Paraná River basin region and 23 blood samples from farm horses were obtained and used for the serological detection of a panel of 19 arboviruses. All samples were analyzed in a hemagglutination inhibition (HI) assay; p...
Greenwood S, Chow-Lockerbie B, Ramsauer S, Wachoski-Dark G, Knight C, Wobeser B. papillomavirus type 2 (EcPV-2) has been recognized as a potential cause of a subset of genital squamous cell carcinomas (SCCs) in horses. In the current study, we measured EcPV-2 seropositivity in 50 healthy horses from Western Canada, and these were compared to a herd of horses with known EcPV-2 exposure. Second, the presence of EcPV-2 DNA was measured using EcPV-2-specific PCR (polymerase chain reaction), performed on a variety of tissues collected at necropsy from 70 horses that lacked any history, gross, or histologic evidence of neoplasia or papillomavirus-associated disease. EcPV-2-spec...
Nugraha AB, Cahyaningsih U, Amrozi A, Ridwan Y, Agungpriyono S, Taher DM, Guswanto A, Gantuya S, Tayebwa DS, Tuvshintulga B, Sivakumar T, Yokoyama N....Equine piroplasmosis is an economically significant disease caused by Theileria equi and Babesia caballi, which are tick-borne hemoprotozoan parasites. Infections with these parasite species had never been reported in horses in Indonesia. The aim of the present study was to investigate the prevalence of T. equi and B. caballi in horses reared in parts of Western Java, Indonesia. Blood samples were collected randomly from 235 horses in four different districts (Bandung, Depok, Tangerang, and Bogor) in Western Java, Indonesia. Thin blood smears prepared from the sampled animals were stained by G...
Reis JK, Diniz RS, Haddad JP, Ferraz IB, Carvalho AF, Kroon EG, Ferreira PC, Leite RC.Equine infectious anemia (EIA) is an important viral infection affecting horses worldwide. The course of infection is accompanied generally by three characteristic stages: acute, chronic and inapparent. There is no effective EIA vaccine or treatment, and the control of the disease is based currently on identification of EIAV inapparent carriers by laboratory tests. Recombinant envelope protein (rgp90) was expressed in Escherichia coli and evaluated via enzyme-linked immunosorbent assay (ELISA). There was an excellent agreement (95.42%) between the ELISA results using rgp90 and agar gel immunod...
Erol E, Jackson CB, Steinman M, Meares K, Donahoe J, Kelly N, Locke S, Smith JL, Carter CN.A comprehensive evaluation of the real-time PCR assay for leptospirosis in comparison with other diagnostic assays on a large-scale basis is fundamental in validating the assay and determining the causes of equine abortions. Objective: To compare and evaluate the diagnostic value of real-time PCR assay for leptospirosis with traditional methods in equine leptospiral abortions. Methods: Cross-sectional observational study. Methods: A Leptospira spp. fluorescent antibody test (FAT), microscopic agglutination test (MAT) and real-time PCR (targeting the LipL32 gene) were compared and evaluated in ...
Cole JR, Hall RF, Gosser HS, Hendricks JB, Pursell AR, Senne DA, Pearson JE, Gipson CA.A group of 14 pregnant mares was exposed via contact to 4 mares bred to stallions infected with equine viral arteritis virus. There was a demonstrable febrile response in each donor mare and in 12 of the pregnant mares. All 18 mares became seropositive after exposure. Equine viral arteritis virus was isolated from the nasopharynx of 5 pregnant mares, but not from the donor mares. Ten of the pregnant mares aborted, and virus was isolated from fetal specimens or placenta of 8.
Glaser AL, Chirnside ED, Horzinek MC, de Vries AA.Equine arteritis virus (EAV) is a small, enveloped, positive-stranded RNA virus, in the family Arteriviridae , W.H.ich can infect both horses and donkeys. While the majority of EAV infections are asymptomatic, acutely infected animals may develop a wide range of clinical signs, including pyrexia, limb and ventral edema, depression, rhinitis, and conjunctivitis. The virus may cause abortion and has caused mortality in neonates. After natural EAV infection, most horses develop a solid, long-term immunity to the disease. Marzz and geldings eliminate the virus within 60 days, but 30 to 60% of acut...
Erganis O, Sayin Z, Hadimli HH, Sakmanoglu A, Pinarkara Y, Ozdemir O, Maden M.This study aimed to determine the effectiveness of a pregnant mare immunization of a Rhodococcus equi (R. equi) vaccine candidate containing a water-based nanoparticle mineral oil adjuvanted (Montanide IMS 3012) inactive bacterin and virulence-associated protein A (VapA), as well as the administration of anti-R. equi hyperimmune (HI) plasma against R. equi challenge in the mares' foals. The efficacy of passive immunizations (colostral passive immunity by mare vaccination and artificial passive immunity by HI plasma administration) was evaluated based on clinical signs, complete blood count, bl...
Fu ZF, Robinson AJ, Horner GW, Dickinson LG, Grimmett JB, Marshall RB.The epizootiology of equine herpesvirus type 2 (EHV-2) infection was investigated in Thoroughbred foals on a stud farm which in previous years had suffered economic loss due to respiratory disease. Sixteen pairs of foals and their dams were selected for this study and all of the foals became infected with EHV-2 by two to four months of age. These animals responded serologically to the virus infection as detected by an enzyme-linked immunosorbent assay (ELISA). EHV-2 infection persisted in these foals for two to six months with constant or intermittent virus recovery. This persistent infection ...
