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.
Soboll G, Hussey SB, Minke JM, Landolt GA, Hunter JS, Jagannatha S, Lunn DP.Equine influenza virus remains an important problem in horses despite extensive use of vaccination. Efficacy of equine influenza vaccination depends on the onset and duration of protective immunity, and appropriate strain specificity of the immune response. This study was designed to test the protective immunity resulting from vaccination with the North American commercial ALVAC equine influenza vaccine (RECOMBITEK Influenza, Merial, USA)(1) against challenge with American lineage influenza viruses. In experiment 1, 12 ponies were vaccinated twice, at a 35 day interval, using the ALVAC-influen...
Jaffer O, Abdishakur F, Hakimuddin F, Riya A, Wernery U, Schuster RK.A total of 105 serum samples from endurance horses from different stables in Dubai were examined for the presence of antibodies against Theileria equi and Babesia caballi using immunofluorescence antibody test (IFAT) and competitive enzyme-linked immunosorbent assay (cELISA). A TaqMan real-time polymerase chain reaction (PCR) was used to detect DNA of piroplasms in specimens of clotted blood or EDTA blood samples of the same animals. Out of the 105 serum samples, the IFAT detected antibodies against T. equi in 35 (33.3%) cases while the cELISA gave 34 (32.4%) positive results. Eleven (10.5%) o...
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...
Shirafuji H, Kanehira K, Kamio T, Kubo M, Shibahara T, Konishi M, Murakami K, Nakamura Y, Yamanaka T, Kondo T, Matsumura T, Muranaka M, Katayama Y.A group of horses immunized with inactivated Japanese encephalitis (JE) vaccine (JE-Immune Group) and a group of non-immunized horses (Non-Immune Group) were infected with West Nile virus (WNV). After WNV infection, neutralizing (Nt) antibody (Ab) titers to WNV were higher than those to JE virus (JEV) in the Non-Immune Group, but the NtAb titers to JEV were higher than those to WNV during most of the post-challenge observation period in the JE-Immune Group. Immunoglobulin M (IgM) Abs to WNV tested positive in the Non-Immune Group but negative in the JE-Immune Group, except for in one horse. Th...
Zoonoses and public healthJuly 30, 2009
Volume 57, Issue 7-8 476-486 doi: 10.1111/j.1863-2378.2009.01245.x
Monaco F, Lelli R, Teodori L, Pinoni C, Di Gennaro A, Polci A, Calistri P, Savini G.In August 2008, West Nile disease re-emerged in Italy. The infection is affecting the North Eastern regions and, as of November 2008, has caused 33 clinical cases and five fatalities in horses. Until now, no deaths have been reported in birds. Mosquitoes, blood, serum and tissue samples, from horses and birds, within and around the outbreak area, have been collected and tested by various methods both serologically and virologically. West Nile virus strains have been isolated from blood samples of one horse and one donkey and from pools of brain, kidneys, heart and spleen of a pigeon and three ...
Yamanaka T, Nemoto M, Tsujimura K, Kondo T, Matsumura T.In horse populations, influenza A virus subtype H3N8 (equine influenza virus, EIV) is a very important pathogen that leads to acute respiratory disease. Recently, EIV has emerged in dogs, and has become widespread among the canine population in the United States. The interspecies transmission route had thus far remained unclear. Here, we tested whether the interspecies transmission of EIV to dogs could occur as a result of close contact with experimentally EIV-infected horses. Three pairs consisting of an EIV-infected horse and a healthy dog were kept together in individual stalls for 15 conse...
Moretti A, Mangili V, Salvatori R, Maresca C, Scoccia E, Torina A, Moretta I, Gabrielli S, Tampieri MP, Pietrobelli M.Babesia caballi and Theileria equi are the causative agents of equine piroplasmosis. In this preliminary epidemiological study, 412 horses reared in central and northern Italy were sampled and three diagnostic methods compared, namely, the microscopy, the indirect fluorescent antibody test (IFAT) and a PCR. Possible risk factors (such as area, season, breed, activity, sex, age, and grazing) associated with serological positivity were evaluated. A seroprevalence of 68.4% was found: 12.4% of the animals had anti-T. equi antibodies, 17.9% anti-B. caballi antibodies and 38.1% had antibodies agains...
Kumar S, Kumar R, Sugimoto C.The donkey population has remained unchanged in the last two decades despite a decrease in the overall population of equids, emphasizing the usefulness of the donkey as a draught and pack animal. Piroplasmosis in donkeys, caused by Theileria equi and Babesia caballi, has been recognized as a serious problem of major economic importance as the affected animals manifest decreased working capacity, loss of appetite, etc. In tropical countries, T. equi infections are more wide-spread and pathogenic than those caused by B. caballi. Donkeys usually remain asymptomatic carriers with positive antibody...
Kaiser A, Meier HP, Doherr MG, Perler L, Zanoni R, Gerber V.Since 1991, no cases of Equine Infectious Anemia (EIA) have been reported in Switzerland. Risk factors for introduction of the virus into Switzerland are still present or have even increased as frequent inapparent infections, large numbers of imported horses, (since 2003) absence of compulsory testing prior to importation, EIA cases in surrounding Europe, possible illegal importation of horses, frequent short-term stays, poor knowledge of the disease among horse owners and even veterinarians. The aim of this study was to provide evidence of freedom from EIA in imported and domestic horses in S...
Berlin D, Loeb E, Baneth G.Trypanosomiasis caused by Trypanosoma evansi ("Surra") is mainly a wasting disease affecting equids, camels and cattle as well as other domestic and wild animal species. In horses, infection may cause severe neurological abnormalities; however, the clinical progression, pathogenesis and molecular ante-mortem detection of this form of the disease have not been described in detail. A mare with progressive ataxia, head tilt, nystagmus and cranial nerve deficits submitted to treatment was diagnosed with central nervous system trypanosomiasis following the detection of a Trypanosoma tryposmastigote...
Blaga R, Cretu CM, Gherman C, Draghici A, Pozio E, Noeckler K, Kapel CM, Dida I, Cozma V, Boireau P.Herbivorous animals are usually, by virtue of their diet, outside the major transmission cycles of Trichinella spp. However, since 1975, the year of the first report of human trichinellosis caused by the consumption of infected horse meat, the domestic horse has appeared as a novel vector of Trichinella spp. infection to humans, with 15 outbreaks documented in France and Italy. Romania, one of the main countries exporting horses into the European Union (EU), experienced a dramatic increase of Trichinella spp. infection in both domestic pigs and humans in the 1990s. Some Trichinella spiralis-in...
Szeredi L, Tenk M, Jánosi S, Pálfi V, Hotzel H, Sachse K, Pospischil A, Bozsó M, Glávits R, Molnár T.Cases of equine abortion and perinatal foal losses were investigated in Hungary during a three-year period (1998-2000). Samples from aborted equine fetuses and newborn foals (total n = 96) were examined using bacteriological, virological, pathological, immunohistochemical (IHC), molecular biological and serological methods. The cause of abortion and perinatal foal loss was identified in 67/96 cases (70%); viral infection was found in 22 (23%), viral and bacterial coinfection in 1 (1%), bacterial infection in 23 (24%), protozoan infection in 1 (1%) and fungal infection in 2 cases (2%). Morpholo...
Pusterla N, Hilton H, Wattanaphansak S, Collier JR, Mapes SM, Stenbom RM, Gebhart C.Equine proliferative enteropathy (EPE) caused by Lawsonia intracellularis has recently been recognized as an emerging disease in foals. Whilst the clinical entity, diagnostic evaluation and treatment of affected foals have been well established and described, preventive measures for EPE have remained largely unaddressed. The objectives of this study were to investigate the humoral immune response and onset and duration of fecal shedding in foals after oral and intra-rectal administration of a modified-live vaccine of L. intracellularis. Foals were vaccinated twice, 3 weeks apart, via oral dren...
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...
Kormann DC, Locatelli-Dittrich R, Richartz RR, Antunes J, Dittrich JR, Patrício LF.In order to evaluate the seroprevalence and the dynamic of anti-Neospora antibodies in pregnant mares, serum samples from 14 animals in the 8th, 9th, 10th and 11th month of pregnancy were analyzed using indirect immunofluorescense technique. Samples diluted 1:50 showed higher seroprevalence on the 8th month (57%) and higher seropositive conversion on the 10th month. 85,7% of the mares were positive for Neospora sp. on at least one month of pregnancy, and seven from that total were positive on the 11th month, three of which showed the highest titles of 1:200 and 1:400. For the samples diluted 1...
Zimmerman KL, Crisman MV.This article is presented with two main goals: (1) to provide equine clinicians with a resource for identifying types of serum tests available and (2) to outline briefly the necessary sample type, assay principle, and relative strengths and weakness of the various methods. Specific etiologies are presented and grouped by clinical diagnosis categories, along with brief comments concerning each disorder and its relevant diagnostic assays. This organization provides an abstracted list of infectious disorders commonly considered for the various clinical presentations and a summary of available ser...
Davidson A, Traub-Dargatz JL, Magnuson R, Hill A, Irwin V, Newton R, Waller A, Smith K, Callan RJ, Meehan M, Owen P, Salman M.Previously published studies have neither used nor reported the results of an indirect enzyme-linked immunosorbent assay (iELISA) to measure serologic responses in natural outbreaks of strangles. The concept of using serologic responses to identify persistent carriers of Streptococcus equi has been proposed but not scientifically evaluated. The specific aims of the current study were to determine the duration and level of truncated fibrinogen-binding protein-specific (SeM allele 1) antibody production in ponies involved in a natural outbreak of strangles and to determine if test results from t...
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...
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-...
Marenzoni ML, Passamonti F, Cappelli K, Veronesi F, Capomaccio S, Supplizi AV, Valente C, Autorino G, Coletti M.Fifteen unweaned thoroughbred foals, born on a stud farm to vaccinated mares, were clinically monitored during their first six months of life and repeatedly tested for equine herpesvirus type 1 (EHV-1) and equine herpesvirus type 4 (EHV-4). Nasopharyngeal swabs and blood samples were collected and screened respectively by PCR and seroneutralisation to detect the presence of the virus, explore its role as a possible cause of respiratory disease, and to assess the efficiency of the pcr for the diagnosis of this disease. The foals were divided into three groups on the basis of their clinical sign...
Hornok S, Edelhofer R, Földvári G, Joachim A, Farkas R.In order to evaluate the seroconversion of horses to Babesia caballi and B. canis in Hungary, blood samples were collected from 371 animals on 23 different locations of the country. The presence of antibodies to B. caballi was screened with a competitive ELISA. All 29 positive samples came from one region (the Hortobágy). The prevalence of infection did not show correlation with sexes, and reached 100% in the age group of 2-5 years. Babesia canis-specific antibodies were demonstrated by IFAT in 6.74% of animals kept in 7 regions. The titres were low or medium level (1:40 to 1:160), indicating...
Duthie S, Mills H, Burr P.Infection with equine arteritis virus is a notifiable disease with sporadic occurrence in the UK. As stallions may harbour the virus after infection, horses are screened for exposure by serological testing prior to breeding. The virus neutralisation test is considered the 'gold standard' serological screening test, but it is time-consuming and labour intensive; consequently there is a move towards more rapid screening methodology. In this study, a commercially available EVA antibody ELISA is assessed. The ELISA performed poorly with a specificity [corrected] of 26% and a sensitivity [corrected...
Nielsen CF, Reisen WK, Armijos MV, Maclachlan NJ, Scott TW.Although horse cases frequently are reported during West Nile virus (WNV) outbreaks, few investigations have focused on the epidemiology of this transmission. From April to October 2003 to 2005, mosquito abundance and infection were monitored 3 days per week at an equine research facility at the University of California, Davis. Thirty-two nonvaccinated horses enrolled as controls in a vaccine study were bled monthly, and their serum was tested for evidence of WNV infection by plaque reduction neutralization test (PRNT). In 2004, one positive Culex pipiens pool was associated with a single hors...
Traversa D, Fichi G, Campigli M, Rondolotti A, Iorio R, Proudman CJ, Pellegrini D, Perrucci S.Anoplocephala perfoliata (Cestoda, Cyclophyllidea), the commonest intestinal tapeworm of horses, can cause colic, intussusceptions, ileal impactions and intestinal perforations. Common diagnostic techniques for A. perfoliata infection, i.e. coprology and serology, show inherent limitations in terms of sensitivity and specificity and new approaches are thus required. Hence, the present study compared the reliability of coprological, serological (i.e. ELISA) and molecular (i.e. nested PCR) methods in detecting A. perfoliata infection in naturally infected horses and in horses treated with a comb...
Acici M, Umur S, Guvenc T, Arslan HH, Kurt M.The prevalence of Theileria equi and Babesia caballi was determined in equid blood samples in five provinces of the Black Sea region of Turkey by using the indirect fluorescent antibody test (IFAT). Of 153 samples, 53 (34.6%) and 33 (21.5%) were seropositive to B. caballi and T. equi, respectively. In addition, 8 (5.2%) of samples were seropositive to both T. equi and B. caballi. Anti T. equi and B. caballi antibodies were detected in all five regions. The prevalence of B. caballi was higher than T. equi in all counties. Antibodies to T. equi and B. caballi were detected in horses of all ages,...
Horta MC, Labruna MB, Pinter A, Linardi PM, Schumaker TT.This study investigated rickettsial infection in animals, humans, ticks, and fleas collected in five areas of the state of São Paulo. Eight flea species (Adoratopsylla antiquorum antiquorum, Ctenocephalides felis felis, Polygenis atopus, Polygenis rimatus, Polygenis roberti roberti, Polygenis tripus, Rhopalopsyllus lugubris, and Rhopalopsyllus lutzi lutzi), and five tick species (Amblyomma aureolatum, Amblyomma cajennense, Amblyomma dubitatum, Ixodes loricatus, and Rhipicephalus sanguineus) were collected from dogs, cats, and opossums. Rickettsia felis was the only rickettsia found infecting ...
Cullinane A, Quinlivan M, Nelly M, Patterson H, Kenna R, Garvey M, Gildea S, Lyons P, Flynn M, Galvin P, Neylon M, Jankowska K.In 2006 there was an outbreak of equine infectious anaemia (EIA) in Ireland. This paper describes the use of the diagnosis of clinical and subclinical cases of the disease. In acute cases the ELISAs and the immunoblot were more sensitive than the AGID. In one mare, fluctuating antibody levels were observed in all the serological assays before it seroconverted by AGID. Viral RNA and DNA were detected by RT-PCR and PCR in all the tissues from the infected animals examined postmortem. The PCR detected viral DNA in plasma regardless of the stage of the disease. In contrast, the RT-PCR detected RNA...
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...
Sahu SP, Alstad AD, Pedersen DD, Pearson JE.Immunoglobulin M (IgM) and G (IgG) capture enzyme-linked immunosorbent assays (ELISAs) were used as possible adjuncts to hemagglutination inhibition (HI) and virus neutralization (VN) tests to differentiate between reaction to recent exposure to eastern equine encephalomyelitis (EEE) virus and those due to prior vaccination. Serum samples were evaluated by the IgM-capture ELISA, and the results were compared with those of HI and VN tests. Of 381 serum samples, 51% (195 samples) were positive by HI test (> or = 1:40) and 54% (205 samples) were positive by VN test (> or = 1:10), but only 3...
EHV1 and EHV4 are the most important herpesviruses in horses. Repeated cases of abortion in mares regularly vaccinated, prompted us to investigate the immune response after vaccination with the same inactivated vaccine, but with three different protocols. Eighteen mares were chosen and randomly divided in three study groups (G-G-G) and a control group (Ctrl). For serologic and PCR investigations nasal swabs, sera and blood were collected. The protocol used in G (4 doses) increased the titer recorded by ELISA and seroneutralization (SN). Poor agreement and no correlation were observed in titer ...
The Journal of infectionMarch 25, 1999
Volume 38, Issue 1 22-23 doi: 10.1016/s0163-4453(99)90023-3
McCormack JG, Allworth AM, Selvey LA, Selleck PW.Determination of potential infectivity of a new paramyxovirus equine morbillivirus (EMV) from horses to humans and humans to humans as a result of two outbreaks in Queensland which involved 23 horses and three humans. Methods: Seroepidemiological testing using neutralizing and immunofluorescing antibodies on people with variable levels of exposure to infected horses and humans. Results: All serological testing on a total of 298 individual contacts was negative. Conclusions: While the three human cases of EMV were probably infected as a result of very close contact with horses, these data sugge...
Jonsdottir S, Torsteinsdottir S, Svansson V, Gudbrandsson J, Stefansdottir SB, Mar Bjornsson J, Runarsdottir A, Marti E.Insect bite hypersensitivity (IBH) is an allergic dermatitis of horses, an IgE-mediated reaction to Culicoides midges. Causative Culicoides spp. are not indigenous in Iceland resulting in high prevalence of IBH in horses born in Iceland and exported as compared to Icelandic horses born in a Culicoides rich environment. The aims were (i) to compare IgE levels in sera of IBH-affected horses born in Iceland (n = 47) with horses of the Icelandic breed (n = 23) and of other breeds (n = 27) born in Culicoides infested area; (ii) to investigate if barley could be a useful production system of allerge...
Martínez J, Montgomery DL, Uzal FA.Vascular mineralization (siderocalcinosis) in the brain of horses has been usually assumed to be an incidental age-related finding with no clinic significance. In the present study, eight 15-32-year-old horses of different breeds with cerebral siderocalcinosis were studied. Four of these horses had acute and severe central nervous system clinical signs of unknown etiology, 2 horses had neurological signs of known cause, and 2 horses did not have neurological signs. Gross examination of the brains in 4 animals revealed symmetrical foci of malacia in the cerebellar white matter. Histologically, ...
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...
Hoane JS, Morrow JK, Saville WJ, Dubey JP, Granstrom DE, Howe DK.Sarcocystis neurona is the primary causative agent of equine protozoal myeloencephalitis (EPM), a common neurologic disease of horses in the Americas. We have developed a set of enzyme-linked immunosorbent assays (ELISAs) based on the four major surface antigens of S. neurona (SnSAGs) to analyze the equine antibody response to S. neurona. The SnSAG ELISAs were optimized and standardized with a sample set of 36 equine sera that had been characterized by Western blotting against total S. neurona parasite antigen, the current gold standard for S. neurona serology. The recombinant SnSAG2 (rSnSAG2)...
Pusterla N, Sanchez-Migallon Guzman D, Vannucci FA, Mapes S, White A, DiFrancesco M, Gebhart C.The aim of this study was to investigate whether feces from rabbits experimentally infected with Lawsonia intracellularis were infectious to foals. Two rabbits were infected with L. intracellularis, while two rabbits served as controls. Eight foals received daily feces from either the infected or the control rabbits. All rabbits and foals were monitored daily for clinical signs for the entire study period (21days for rabbits, 42days for foals). Feces and blood were collected for the PCR detection of L. intracellularis and serologic analysis, respectively. None of the infected rabbits or foals ...
Sillerud CL, Bey RF, Ball M, Bistner SI.After the observation of 2 horses with uveitis on a horse farm in the Minnesota River valley, 100 horses from this geographic area were given ophthalmologic examinations and were evaluated serologically for leptospirosis. A statistically significant (P less than 0.001) association was observed between the finding of antibodies against Leptospira interrogans serovar pomona and uveitis.
van den Ingh TS, Binkhorst GJ, Kimman TG, Vreeswijk J, Pol JM, van Oirschot JT.A horse with neurological signs and severe meningoencephalitis caused by Aujeszky's disease is described. The diagnosis was established by immunohistochemistry, DNA-in situ hybridization and serological tests. Aujeszky's disease virus antigen and Aujeszky's disease viral DNA were detected in neurons of the cerebrum. In the serum of the horse antibodies against Aujeszky's disease virus were detected in a virus neutralization test, in a blocking ELISA which specifically detects antibodies against the glycoprotein I (Ig) of the virus, in an indirect double sandwich ELISA and with colloidal gold i...
Bhagwan J, Kumar A, Kumar R, Goyal L, Goel P, Kumar S.A sizeable Indian equine population is considered to be pre-immune carrier of Theileria equi infection. In this study we confirmed the presence of T. equi specific DNA in Hyalomma anatolicum ticks which were infested on sero-positive horses. Fifty two Indigenous horses were randomly selected from endemic areas and their blood and tick samples were collected. Tick salivary glands and blood samples were processed for separation of DNA and serum, respectively. Serum samples were analyzed by EMA-2ELISA and nine horses were found positive for T. equi specific antibodies. Species-specific primers we...
Skalka B.The occurrence of equi-factor antibodies in sera of mares and their foals was studied on two horse breeding farms, one of which (Farm A) had a positive and the other (farm B) a negative history of R. equi infection of foals. The equi-factor neutralization (EFN) and the reverse Elek-Ouchterlony (REO) precipitation were used as assays. On Farm A, 25 mares positive in both tests (EFN+ REO+) and 25 mares negative in both tests (EFN- REO-) was chosen. On Farm B, a group of 25 EFN- REO+ mares and a group of 25 EFN- REO- mares were studied. The first serum samplings in mares were 1 week ante partum a...
Schvartz G, Epp T, Burgess HJ, Chilton NB, Lohmann KL.To investigate the agreement between available serologic tests for the detection of antibodies against Anaplasma phagocytophilum and Borrelia burgdorferi, 50 serum samples from horses of unknown clinical status and at low risk for infection were tested. In addition to a point-of-care enzyme-linked immunosorbent assay (pocELISA), the evaluated tests included 2 indirect fluorescent antibody tests (IFATs) for antibodies against A. phagocytophilum and an IFAT, an ELISA confirmed with Western blot, and the Lyme multiplex assay for antibodies against B. burgdorferi. For each pair-wise comparison bet...
Cauchard J, Soldan A, Madeline A, Johnson P, Büscher P, Petry S.To evaluate the reproducibility of routine serological methods to detect Trypanosoma equiperdum antibodies in equine sera, two inter-laboratory ring trials were organized involving 22 European and 4 non-European reference laboratories for dourine. The serological methods were the complement fixation test (CFT; 25 laboratories) and the indirect fluorescent antibody test (IFAT; 4 laboratories). Three of the laboratories applied both these methods. The sample panels were composed of sera that were negative, positive or suspected for dourine. Of the negative sera, one was from a donkey naturally i...
Ammar AM, Heitmann J, Kirchhoff H.After abortion sera were taken from 58 thoroughbred and other mares of the northwestern part of Germany and investigated by ELISA (enzyme linked immuno-sorbent assay) for antibodies against Mycoplasma equirhinis, M. subdolum, M. equigenitalium, M. pulmonis, M. felis, Acholeplasma laidlawii, A. hippikon, and A. equifetale. Reactions at serum dilutions of 1:32 and higher were considered as positive. At serum dilution 1:32 no antibodies were found in 11 sera. The remaining sera showed antibodies against one or more of the mycoplasma antigens investigated. The number of multiple reactions decrease...
Bażanów B, Pawęska JT, Pogorzelska A, Florek M, Frącka A, Gębarowski T, Chwirot W, Stygar D.Huculs () are an old breed of primitive mountain horses, originating from the Carpathian Mountains. To the best of our knowledge, data concerning the epidemiology of viral infections observed within this breed are sparse. The objective of this study was to estimate the serological status of a semi-isolated, unvaccinated Hucul herd, with respect to both common equine viral infections and horse-infecting arboviruses, the presence of which was previously reported in Poland. Twenty horses of the Hucul breed, living in a remote area in Poland, were studied in 2018 from March to May. Using nasal sec...
Tewari D, Gibson JS, Slater JD, O'Neill T, Hannant D, Allen GP, Field HJ.EHV-1 was inoculated into specific pathogen-free (SPF) foals in order to study uncomplicated primary responses. Infection resulted in a strong serological response recognizing EHV-1-specific antigens; this contrasts with a previous publication where a weak response was recorded in SPF animals. Antibodies to EHV-1 were readily detected by four techniques (virus neutralization, complement fixation, Western blots and immune precipitation), yet there was comparatively little cross-reaction to EHV-4 target antigen. Re-inoculation with the same virus strain stimulated antibodies to EHV-1 but no addi...
Ogilvie TH, Rosendal S, Blackwell TE, Rostkowski CM, Julian RJ, Ruhnke L.Mycoplasma felis was the only organism recovered from the thoracic cavity of a horse with pleuritis. Large numbers of mildly degenerative neutrophils were in the pleural fluid. The horse developed a serologic response to M felis and recovered during hospitalization. Experimentally, a pony was inoculated in the thoracic cavity with a pure culture of the M felis isolate suspended in the pony's serum. A control pony was inoculated with serum only. Within 48 hours, the principal pony developed fever, increased respiratory rate, pleural effusion, and signs of pain. A highly cellular exudate with no...
Carmichael RC, Duell JR, Holbrook TC, Herrin BH, Leutenegger CM, O'Connor TP, Little SE.Abstract Tick infestations and infection with tick-borne agents are commonly recognized in horses in North America, but equine infection with true Ehrlichia spp. has not been described. To determine the degree to which horses in the south-central United States are naturally exposed to and infected with tick-borne disease agents, serum samples were collected at random (n=240) or from horses with active tick infestations (n=73) and tested by immunofluorescence antibody assay (IFA) and/or enzyme-linked immunosorbent assay (ELISA) for evidence of antibodies reactive to Ehrlichia spp., Anaplasma sp...
Quigley A, Sekiya M, Garcia-Campos A, Paz-Silva A, Howell A, Williams DJL, Mulcahy G.Fasciola hepatica is a common parasite of livestock in Ireland, causing significant economic losses and affecting animal welfare. A previous abattoir study of 200 horses led to an estimated 9.5 % prevalence of infection in horses slaughtered in Ireland. However, the epidemiology and pathogenic significance of this infection in this species is not well-described. The objectives of this study were to determine the susceptibility of horses to oral challenge infection with F. hepatica metacercariae, and to document the course of the infection along with serological and biochemical response. We att...
Kleiboeker SB, Loiacono CM, Rottinghaus A, Pue HL, Johnson GC.The North American West Nile virus (WNV) epizootic, which began in 1999, has caused significant morbidity and mortality in horses. Because experimental infection has failed to consistently produce encephalitis in inoculated horses, investigation of naturally occurring cases was used to optimize strategies for diagnosis of this disease. Although WNV RNA could be detected by reverse transcriptase-polymerase chain reaction (RT-PCR) performed on whole blood collected from both clinically affected horses and unaffected herdmates, the diagnostic sensitivity of this approach was low compared with IgM...
Sofronic-Milosavljevic L, Pozio E, Patrascu IV, Skerovic N, Gomez Morales MA, Gamble HR.From 1998 to 2000, 5,267 horse sera were collected from several Trichinella regions in Romania. Sera were initially screened in laboratories in Romania, Serbia and Italy with an ELISA and a Western blot (Wb) using an excretory/secretory (ES) antigen and several conjugates (protein A, protein G, and sheep or goat anti-horse). Differences in serology results were obtained among the different conjugates and also between ELISA and Wb. Depending on the test used, specific antibodies were found at a prevalence rate of 3-6% of horses. Serum samples classified as positive were tested again by ELISA us...
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...
Niroomandi E, Maleki S, Abdollahpour G, Zakian A, Ahmadvand H.Leptospirosis is one of the important zoonotic bacterial diseases with a worldwide distribution that is often subclinical. We aimed to investigate the oxidant/antioxidant balance and acute-phase response in naturally infected horses and cattle with Leptospira interrogans. A total of 600 serum samples from horses and cattle were examined for L. interrogans antibodies using the microscopic agglutination test to determine anti-Leptospira IgG antibodies against a panel of eight important Leptospira antigens in Iran. Then, serum total antioxidant capacity, catalase, glutathione peroxidase, and malo...
Brown CC, Olander HJ, Biberstein EL, Moreno D.Fifteen goat kids were experimentally inoculated with Corynebacterium pseudotuberculosis. Five were given a strain of caprine origin (nitrate-negative biotype) intradermally, 5 were given a strain of equine origin (nitrate-positive biotype) intradermally, and 5 were inoculated intranasally with the caprine-origin strain. Animals were monitored for 127 days. The goats given the inocula intradermally developed abscesses; those given caprine-origin strain had multiple lesions both peripherally and in visceral locations (primarily endothoracic abscesses), whereas those given the equine-origin stra...
Ogunremi O, Georgiadis MP, Halbert G, Benjamin J, Pfister K, Lopez-Rebollar L.The indirect fluorescent antibody (IFA) test for Theileria equi was evaluated to assess test's suitability for the serological diagnosis of equine piroplasmosis, to provide performance parameters for the purpose of test validation, and to compare it with the complement fixation (CF) test. Using a protocol that included Evan's blue, the specificity of the IFA test was estimated at 99.0% for T. equi by the classical method of analysis, and 96.6% by the Bayesian method. The use of Evan's blue in the test protocol increased test specificity and contributed to an excellent test agreement between tw...
Monzón CM, Hoyos CB, Jara GA.Tests on 257 blood samples from 21 herds of horses in Formosa Province of Argentina, using the technique of centrifuging microhaematocrit capillary tubes, revealed Trypanosoma evansi in 90 of 137 animals in eight herds. Application of the direct agglutination test to serum samples from the same animals revealed antibodies to T. evansi in 107 horses. Antibody was also detected in nine horses from two herds where the parasite was not detected. Outbreaks of 'mal de caderas' occurred in the humid (eastern) and sub-humid (central) zones of Formosa. More than 95% of the equine population of the prov...
Hamond C, Adam EN, Stone NE, LeCount K, Anderson T, Putz EJ, Camp P, Hicks J, Stuber T, van der Linden H, Bayles DO, Sahl JW, Schlater LK, Wagner DM....Equine leptospirosis can result in abortion, stillbirth, neonatal death, placentitis, and uveitis. Horses can also act as subclinical reservoir hosts of infection, which are characterized as asymptomatic carriers that persistently excrete leptospires and transmit disease. In this study, PCR and culture were used to assess urinary shedding of pathogenic Leptospira from 37 asymptomatic mares. Three asymptomatic mares, designated as H2, H8, and H9, were PCR-positive for lipL32, a gene specific for pathogenic species of Leptospira. One asymptomatic mare, H9, was culture-positive, and the recovered...
Chevalier N, Migné CV, Mariteragi-Helle T, Dumarest M, De Mas M, Chevrier M, Queré E, Marcillaud-Pitel C, Lupo C, Bigeard C, Touzet T, Leblond A....The circulation of West Nile virus (WNV), Usutu virus (USUV), and tick-borne encephalitis virus (TBEV) was investigated in south-western France during the first six months of 2023, following the emergence of WNV in equids in Gironde, a département in south-western France, in 2022. Blood samples were collected from 494 horses located in the Gironde département and divided into three zones: the Confluence zone, the Intermediate zone and the Arcachon Basin. Samples were tested for WNV-, USUV- and TBEV-specific antibodies. An overall seroprevalence of 14% (95% CI [11-18%]) for orthoflavivirus an...