Polymerase Chain Reaction (PCR) is a molecular biology technique used to amplify specific DNA sequences, allowing for detailed genetic analysis in horses. This method enables the detection and quantification of genetic material, facilitating research in areas such as genetic disorders, infectious diseases, and population genetics in equine species. PCR applications in horses include identifying pathogens, verifying parentage, and studying genetic variations. The technique's sensitivity and specificity make it a valuable tool in equine veterinary diagnostics and research. This page compiles peer-reviewed research studies and scholarly articles that explore the applications, methodologies, and advancements of PCR in equine science.
Ybañez AP, Ybañez RHD, Talle MG, Arreglo RMT, Geens MJC, Villas JGI, Villar SR, Laruga CL, Cao S, Moumouni FPA, Liu M, Igarashi I, Xuan X.Theileria equi and Babesia caballi are tick-borne protozoan parasites that can cause anemia in horses. In the Philippines, serological detection of these parasites has only been reported in the Northern area (Luzon). In this study, 105 horses from Cebu and Bohol, Philippines were tested using peripheral blood smear examination (PBSE), immunochromatographic test (ICT) strips, and PCR. Clinical history, presenting clinical signs and complete blood count were obtained. Results revealed that although all horses were negative using PBSE, 23 (21.9%) were positive (12 for T. equi, and 11 for B. cabal...
Vissani MA, Tordoya MS, Tsai YL, Lee PA, Shen YH, Lee FC, Wang HT, Parreño V, Barrandeguy M.Equine coital exanthema (ECE) is an infectious, venereally transmitted muco-cutaneous disease affecting mares and stallions, caused by equid alphaherpesvirus 3 (EHV3). Diagnostic tools for rapid identification of EHV3 are of primary importance to diminish the risk of EHV3 dissemination at the time of breeding. In the last years, it has been shown that the performance of the insulated-isothermal polymerase chain reaction (iiPCR) is comparable to virus isolation, nested PCR and real-time PCR (qPCR) in detecting pathogens of various animal species. Analytical sensitivity and specificity of the ii...
Saleem S, Ijaz M, Farooqi SH, Ghaffar A, Ali A, Iqbal K, Mehmood K, Zhang H.Equine granulocytic anaplasmosis (EGA) is an important tick borne disease of equines that is caused by Anaplasma phagocytophilum (A. phagocytophilum). The etiological agent has veterinary as well as public health importance because of its zoonotic nature. A. phagocytophilum causes an acute illness in equines with loss of appetite, lethargy, hemorrhages and lameness. Clinically, EGA is diagnosed upon examination of morulae within neutrophils especially granulocytes in the blood. The best diagnostic tool for the detection of EGA is Polymerase chain reaction (PCR). Previous studies suggested that...
Mira J, Herman M, Zakia LS, Olivo G, Araújo JP, Borges AS, Oliveira-Filho JP.Despite the reported association between aural plaques and the presence of Equus caballus papillomavirus (EcPV), there are few data regarding the distribution of viral types in different geographic regions or possible correlations for different papillomaviruses and lesion characteristics. We detected the presence and frequency of EcPV (1-7) DNA in aural plaque biopsies of horses from different regions of Brazil and identified the patterns of these infections or coinfections and their possible association with lesion severity. A total of 108 aural plaque biopsies from horses in the 5 geopolitic...
Rivera-Páez FA, Martins TF, Ossa-López PA, Sampieri BR, Camargo-Mathias MI.Rickettsiosis are emerging or re-emerging diseases, with a worldwide distribution associated to transmission by arthropod vectors. Rickettsia species belong to the spotted fever group (SFG) and are transmitted by hard ticks (Acari: Ixodidae) that may act as vectors and reservoirs. This study carried out a molecular detection of Rickettsia from 7 species of the family Ixodidae collected from domestic hosts by PCR amplification of fragments of the citrate synthase "gltA" gene and outer membrane protein "ompA" gene. Of the 204 samples analyzed, 11.3% (23) were positive for rickettsial infection. ...
Lobanov VA, Peckle M, Massard CL, Brad Scandrett W, Gajadhar AA.Equine piroplasmosis (EP) is an economically significant infection of horses and other equine species caused by the tick-borne protozoa Theileria equi and Babesia caballi. The long-term carrier state in infected animals makes importation of such subclinical cases a major risk factor for the introduction of EP into non-enzootic areas. Regulatory testing for EP relies on screening of equines by serological methods. The definitive diagnosis of EP infection in individual animals will benefit from the availability of sensitive direct detection methods, for example, when used as confirmatory assays ...
Boyle AG, Timoney JF, Newton JR, Hines MT, Waller AS, Buchanan BR.This consensus statement update reflects our current published knowledge and opinion about clinical signs, pathogenesis, epidemiology, treatment, complications, and control of strangles. This updated statement emphasizes varying presentations in the context of existing underlying immunity and carrier states of strangles in the transmission of disease. The statement redefines the "gold standard" for detection of possible infection and reviews the new technologies available in polymerase chain reaction diagnosis and serology and their use in outbreak control and prevention. We reiterate the impo...
Gressler LT, Machado G, da Silveira BP, Cohen ND, Corbellini LG, Leotti VB, Diehl GN, Dos Santos LC, de Vargas AC.Rhodococcus equi is an important cause of foal pneumonia. While its isolation from different sources has been widely evaluated, there is a need to better understand the R. equi epidemiology from samples of the nasal cavity of healthy horses. Objective: To determine the prevalence of R. equi from the nasal cavity of healthy horses, along with its virulence profile, antimicrobial susceptibility and environmental variables associated. Methods: Cross-sectional study. Methods: Swabs from the nasal cavity of 1010 apparently healthy horses from 341 farms were submitted for bacteriological analyses. T...
Socoloski SNG, de Castro BG, Cordeiro MD, da Fonseca AH, Cepeda MB, Nicolino RR, Lopes LB.Borrelia burgdorferi sensu stricto is the main etiological agent of Lyme disease (LD) in the USA. In Brazil, it is believed that a similar spirochete is the causal agent of the Baggio-Yoshinari syndrome (BYS), a zoonosis also transmitted by ticks, whose clinical manifestations are similar to those of LD. Despite the epidemiological importance, there are no studies reporting the presence and the prevalence of B. burgdorferi among horses in Mato Grosso State. The aim of this study was to detect and measure the frequency of IgG antibodies anti-B. burgdorferi American strain G39/40 in horses in th...
Pöschke A, Krähling B, Failing K, Staszyk C.The equine periodontal ligament (PDL) is a fibrous connective tissue that covers the intra-alveolar parts of the tooth and anchors it to the alveolar bone-it, therefore, provides a similar function to a tendinous structure. While several studies have considered the formation and structure of tendons, there is insufficient information particularly on the molecular composition of the PDL. Especially for the equine PDL, there is limited knowledge concerning the expression of genes commonly regarded as typical for tendon tissue. In this study, the gene expression of, e.g., (, and fibrocartilage m...
Vieira MIB, Costa MM, de Oliveira MT, Gonçalves LR, André MR, Machado RZ.Equine piroplasmosis is a disease caused by the hemoparasites Babesia caballi and Theileria equi and is considered to be the most important parasitic infection affecting Equidae. The objective of the present study was to carry out an epidemiological molecular and serological survey for the presence of these two protozoal organisms in equids from the northwestern region of the State of Rio Grande do Sul (RS), south Brazil. For this purpose, blood samples were collected from 90 equids in the city of Passo Fundo, RS, Brazil. Those were animals used for sport activities, outdoor recreational ridin...
Tesena P, Korchunjit W, Taylor J, Wongtawan T.Gastric tissue biopsy and gene expression analysis are important tools for disease diagnosis and study of the physiology of the equine stomach. However, RNA extraction from gastric biopsy samples is a complex procedure because the samples contain low quantities of RNA and are contaminated with mucous protein and bacterial flora. The objectives of these studies were to compare the performance of RNA extraction methods and to investigate the sensitivity of commercial qPCR master mixes for gene expression analysis of gastric biopsy samples. Three commercial RNA extraction methods (TRIzol, GENEzol...
Sabir N, Chaudhry ZI, Aslam A, Muhammad K, Shahid M, Hussain A, Khan SA, Ahmad I.Trypanosomiasis is an important protozoal disease with a diverse range of susceptible host including human. In the current study, molecular characterization of prevalent species was done through a pan-trypanosome polymerase chain reaction (PCR) followed by restriction fragment length polymorphism (RFLP). A total of three hundred (n = 300) equines including horses, donkeys and mules (100 each) were randomly selected and the equine blood samples were subjected to screening for trypanosomes through microhaematocrit centrifuge technique (MHCT), conventional PCR, semi-nested PCR and RFLP. Overall...
Nyaoke AC, Navarro MA, Beingesser J, Uzal FA.A 14-y-old bay Quarter Horse gelding was presented with progressive neurologic signs, elevated rectal temperature, and icterus for 3 d prior to death. Postmortem examination revealed icterus, large amounts of serosanguineous fluid in the abdominal cavity, widespread petechiae and ecchymoses in several organs, and a large, pale, and well-demarcated focus of necrosis in the liver. Histologically, there was coagulative necrosis surrounded by a rim of inflammatory cells and large numbers of gram-positive rods, which were identified as Clostridium novyi by immunohistochemistry. Liver samples tested...
Haspeslagh M, Vlaminck L, Martens A.The association between bovine papillomavirus (BPV) and equine sarcoids is well established, but it is unclear how the virus spreads. Although evidence in support of viral spread through direct animal contact exists, this does not explain sarcoid development in isolated equids. BPV DNA has been detected in flies, which could indicate that these insects serve as a vector. This study aimed to investigate whether BPV-negative stable flies (Stomoxys calcitrans) become positive for BPV DNA after exposure to equine sarcoid or bovine papilloma tissue under experimental conditions and, if so, for how ...
Peat FJ, Colbath AC, Bentsen LM, Goodrich LR, King MR.This study aimed to examine the influence of neodymium-doped yttrium aluminum garnet (Nd:YAG) laser irradiation on equine bone marrow-derived mesenchymal stem cell (MSC) viability, proliferation, and cytokine expression in vitro. Background: Photobiomodulation of cells using monochromatic light is a technique designed to influence cellular processes. Previous studies have shown dose-dependent effects of low-level laser irradiation on cell proliferation and cytokine expression in a range of cell types and species. Evidence for the influence of 1064 nm wavelength near-infrared irradiation on M...
Vieira FT, Acosta ICL, Martins TF, Filho JM, Krawczak FDS, Barbieri ARM, Egert L, Fernandes DR, Braga FR, Labruna MB, Dietze R.This work aims to identify and quantify the percentage of Rickettsia spp., Ehrlichia spp., Babesia spp. and Hepatozoon spp. positive pet dogs, and to identify ticks collected on these animals in the state of Espírito Santo, in the Southeast region of Brazil. The study included 378 dogs, 226 females and 152 males, of various breeds and ages (mean age of 4.1 years). All animals were examined for ticks, and whole blood was collected and processed by conventional PCR protocols for Babesia spp., Anaplasmataceae, Hepatozoon spp. and by real-time PCR for Ehrlichia canis. Of the 378 dogs examined, 15...
Dong J, Bao H, Mang L.Rhinoestrus sp. (Diptera: Oestridae) is an economically important parasite that can cause severe nasal myiasis in equids and can also affect humans. The ultrastructure of all Rhinoestrus sp. larval instars from Mongolian horse was examined by light and scanning electron microscopy to characterize the features of Rhinoestrus. The structure of the anterior region, posterior region, and the spines of the third segment was analyzed for 10 specimens in each larval stage. Additionally, 34 third-instar (L3) larvae of Rhinoestrus sp. from Mongolian horse were subjected to molecular characterization by...
Magni E, Bertelloni F, Sgorbini M, Ebani VV.To investigate the occurrence of Bartonella sp. infection in asymptomatic horses and donkeys living in Tuscany, Central Italy. Methods: Blood samples were collected from 77 horses and 15 donkeys and tested by indirect immunofluorescent test to detect antibodies against Bartonella sp. and by PCR to detect the pathogen. Results: Fifty-four (58.69%; 95% CI: 47.95%-68.87%) animals, 9 donkeys and 45 horses, were seropositive with antibody titers ranging from 1:64 to 1:512. PCR assays detected 9 horses positive for Bartonella sp. and 3 donkeys for Bartonella henselae genotype I. Conclusions: The det...
Sharav T, Konnai S, Ochirkhuu N, Ts EO, Mekata H, Sakoda Y, Umemura T, Murata S, Chultemdorj T, Ohashi K.The genetic characterization and actual prevalence of EIAV in Mongolian horse in the disease endemic region is currently unknown. Here, 11 of 776 horse serum samples from four Mongolian provinces tested positive on agar gel immunodiffusion test. Genomic DNA extracted from all seropositive samples was subjected to nested PCR assay. Among these, three samples tested positive with nested PCR assay and were identified by sequencing analysis based on long termination repeat and tat gene of the virus. Two of the three sequences were identical, with 94.0% identity with the third. These two independen...
Haspeslagh M, Jordana Garcia M, Vlaminck LEM, Martens AM.Previous studies mention the use of topical acyclovir for the treatment of equine sarcoids. Success rates vary and since the bovine papillomavirus (BPV) lacks the presence of a kinase necessary to activate acyclovir, there is no proof of its activity against equine sarcoids. Results: Twenty-four equine sarcoids were topically treated with acyclovir cream and 25 with a placebo. Both creams were applied twice daily during 6 months. Before the start of the treatment and further on a monthly basis, photographs and swabs were obtained. On the photographs, sarcoid diameter and surface area were meas...
Almeida S, Dorneles EMS, Diniz C, Abreu V, Sousa C, Alves J, Carneiro A, Bagano P, Spier S, Barh D, Lage AP, Figueiredo H, Azevedo V.Corynebacterium pseudotuberculosis is classified into two biovars, nitrate-negative biovar Ovis which is the etiologic agent of caseous lymphadenitis in small ruminants and nitrate-positive biovar Equi, which causes abscesses and ulcerative lymphangitis in equines. The aim of this study was to develop a quadruplex PCR assay that would allow simultaneous detection and biovar-typing of C. pseudotuberculosis. Methods: In the present study, genomes of C. pseudotuberculosis strains were used to identify the genes involved in the nitrate reduction pathway to improve a species identification three-pr...
Montes-Cortés MG, Fernández-García JL, Martínez-Estéllez MÁH.Equine piroplasmosis is caused by two haemoprotozoan parasites: and . Negative economic impact on international trade has been associated to endemic sites. This is the reason why carrier detection requires reliable diagnostic methods. Various diagnostic modalities can be used alone or in combination including PCR. However, genetic variation of commonly used genes is still of debate. The aim of this research was to sequence the β-tubulin gene of a strain from Spain and to compare it with known β-tubulin sequences. Methods: DNA was isolated from a cryopreserved strain from Spain and acute an...
Usuga A, Rojano BA, Restrepo G.Contribution of seminal plasma proteins to semen freezability has been reported in several species, suggesting these proteins as genetic markers. The aim of this study was to evaluate the relationship between cysteine-rich secretory protein-3 (CRISP-3) and some of its single-nucleotide polymorphisms (SNPs) with post-thawing semen quality in stallions. DNA was obtained from 100 stallions, regions of interest were amplified by polymerase chain reaction and sequenced. Evaluated SNPs within the equine CRISP-3 gene were CRISP3c.+199A>G (SNP1), CRISP3c.+566C>A (SNP2), CRISP3c.+622G>A (SNP3)...
Wise LN, Kappmeyer LS, Silva MG, White SN, Grause JF, Knowles DP.Certain countries including the United States remain non-endemic for particular infectious diseases such as equine piroplasmosis through import restrictions and surveillance. Endemic regions often employ premunition as the primary method to control disease, however in non-endemic countries, chemosterilization combined with methods to confirm parasite elimination are required to maintain disease-free status. The ability of imidocarb diproprionate (ID) to clear persistent Theileria equi infection from infected horses has been shown through the inability of treated horses to transmit via blood tr...
Bera BC, Virmani N, Kumar N, Anand T, Pavulraj S, Rash A, Elton D, Rash N, Bhatia S, Sood R, Singh RK, Tripathi BN.Equine influenza is a major health problem of equines worldwide. The polymerase genes of influenza virus have key roles in virus replication, transcription, transmission between hosts and pathogenesis. Hence, the comprehensive genetic and codon usage bias of polymerase genes of equine influenza virus (EIV) were analyzed to elucidate the genetic and evolutionary relationships in a novel perspective. Results: The group - specific consensus amino acid substitutions were identified in all polymerase genes of EIVs that led to divergence of EIVs into various clades. The consistent amino acid changes...
Linder KE, Bizikova P, Luff J, Zhou D, Yuan H, Breuhaus B, Nelson E, Mackay R.Currently, seven equine papillomaviruses (PV) are known and are associated with one of three different and distinct clinical presentations. Objective: To report the clinical, histopathological and immunohistochemical findings in horses with generalized papillomatosis associated with a novel equine PV, Equus caballus papillomavirus 8 (EcPV8). Methods: Three client-owned quarter horses. Methods: Case report, retrospective. Results: Dozens to thousands of papillomas involved the axilla, inguinal area and proximal limbs as well as the ventral and lateral neck, thorax and abdomen. Lesions were some...
Sim RR, Joyner PH, Padilla LR, Anikis P, Aitken-Palmer C.Anaplasma phagocytophilum is a tick-borne pathogen of domestic horses and the causative agent of equine granulocytic anaplasmosis. This case series describes three confirmed cases of clinical anaplasmosis, and a fourth case of presumptive anaplasmosis in Przewalski's horses ( Equus ferus przewalskii) housed at the Smithsonian Conservation Biology Institute from 2008 to 2014. Clinical signs varied among individuals with affected horses exhibiting lethargy, weakness, pyrexia, hypophagia, reluctance to move, or ataxia. Anaplasmosis cases were confirmed with a combination of identification of neut...
Zhang Y, Chahan B, Liu S, Song R, Li Y, Huercha , Guo Q, Wu H, Zhu Y.In order to found the epidemiological situation of T. equi in the horse herds in Ili Prefecture of Xinjiang Province, 723 blood samples collected from 4 counties and districts were test for T. equi through microscopic detection and Polymerase chain Reaction (PCR). In the result, we found that the 295 of 723 blood samples (40.8%) were positive for T. equi infection. The results showed that the choosed counties have a varying degrees infection. To our knowledge, this is the first time that we detected T. equi infection using the molecular techniques from Ili in Xinjiang Uygur Autonomous region.
Laabassi F, Hue E, Fortier C, Morilland E, Legrand L, Hans A, Pronost S.An episode of acute equine respiratory infection was reported in western Algeria (Tiaret province) between February and March 2011, affecting a large population of horses. Nasal swabs (n=100) were taken from horses aged between 1 and 27 years, presenting with cough and mucopurulent nasal discharge. The prevalence of equine respiratory virus infections was examined using quantitative polymerase chain reaction (qPCR). One, or more, of four equine respiratory viruses were detected in the nasal swabs of 90 of 100 horses (90%) and the detection rate of equine herpesvirus type 1 (EHV-1), equine herp...
Langemeier JL, Cook SJ, Cook RF, Rushlow KE, Montelaro RC, Issel CJ.Control of equine infectious anemia (EIA) is currently based on detection of anti-EIA virus (EIAV) antibodies. However, serologic diagnostic methods may give false-negative results in infected horses that fail to respond adequately or are in the early stages of infection. We developed a reverse transcriptase nested PCR (RT-nPCR) assay for the detection of viral gag gene sequences in plasma from EIAV-infected horses. The ability of RT-nPCR to detect field strains of EIAV was investigated by assaying plasma samples from 71 horses stabled on EIA quarantine ranches. Positive PCR signals were detec...
Bhoora R, Buss P, Guthrie AJ, Penzhorn BL, Collins NE.Seventy EDTA blood samples collected from plains zebra (Equus quagga burchellii) and Cape mountain zebra (Equus zebra zebra) were screened for the presence of piroplasm parasite DNA using quantitative T. equi-specific and B. caballi-specific TaqMan real-time PCR (qPCR) tests. T. equi parasite DNA was detected in 60 samples, 19 of which were also positive for B. caballi. Approximately 1480bp of the piroplasm 18S rRNA gene was amplified and sequenced from 17 samples, while the V4 hypervariable region of the 18S rRNA gene was amplified, cloned and sequenced from 31 samples. BLASTN analysis reveal...
Binns MM, Daly JM, Chirnside ED, Mumford JA, Wood JM, Richards CM, Daniels RS.The haemagglutinin (HA) gene from the equine influenza H3N8 isolate Suffolk/89 has been cloned by reverse transcription and polymerase chain reaction amplification. The nucleotide sequence of the HA gene was determined from two independently cloned copies of the gene and was found to be most closely related to recent American isolates supporting the idea that most isolates of equine H3N8 are evolving as a single lineage. When the predicted amino acid sequence of the Suffolk/89 HA was examined, changes had taken place in at least four of the major antigenic sites, A, B, C, and D when compared t...
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...
Zientara S, Sailleau C, Moulay S, Cruciere C.A single tube reverse transcription-polymerase chain reaction (RT-PCR) method for detection of African horse sickness virus (AHSV) in splenic tissues from infected horses is described. Double stranded RNA was extracted from infected organs of horses and used to produce complementary DNA (cDNA) with the two primers selected for the PCR. The 1179 bp amplified product (the segment 7 which encodes for VP 7), detected by electrophoresis on agarose gel and ethidium bromide staining, was hydrolysed with eight restriction endonucleases for characterization of the AHSV. The sensitivity of this method i...
Dong JB, Zhu W, Cook FR, Goto Y, Horii Y, Haga T.Equine infectious anemia (EIA) has posed a major challenge and caused significant losses to the equine industry worldwide. PCR detection methods have considerable potential as an adjunct to conventional serological diagnostic techniques. However, most published PCR methods, including that recommended by the OIE, were designed using laboratory-adapted virus strains and do not function with field isolates of EIA virus (EIAV). In the present study, a nested PCR assay for detection of EIAV proviral DNA in peripheral blood cells of naturally infected horses was developed. Primer sets were designed ...
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 ...
Valente JDM, Mongruel ACB, Machado CAL, Chiyo L, Leandro AS, Britto AS, Martins TF, Barros-Filho IR, Biondo AW, Perotta JH, Campos ANS, Vidotto O....Tick-borne diseases (TBD) constitute an important group of illness affecting animals and humans worldwide. In Brazil, carthorses are frequently exposed to ticks and tick-borne pathogens, leading to impairment of horse performance and imposing restrictions by the international veterinary authorities for the importation of horses. Accordingly, this study has aimed to i) determine the prevalence of the TBD agents Theileria equi, Babesia caballi, Ehrlichia spp., and hemotropic mycoplasmas in carthorses, ii) identify the tick species parasitizing the animals, and iii) determine factors associated w...
Riihimäki M, Aspán A, Ljung H, Pringle J.The aim of the study was to use culture, qPCR and seM sequencing to map Streptococcus equi subspec. equi (S.equi) isolates in long term carrier animals. A strangles outbreak affecting 41 Icelandic horses was followed to determine strangles free status using nasal and/or guttural pouch lavages collected serially on eleven separate occasions over 13 months. Ten persistent carriers, of which eight had repeated culture positive samples for S. equi, were selected for the study. Of 115 samples collected, 61 were S. equi positive on qPCR; from which 32 were also culture positive. Amplification of par...
Baptista C, Lopes MS, Tavares AC, Rojer H, Kappmeyer L, Mendonça D, da Câmara Machado A.Equine piroplasmosis is a tick-borne disease of equids that is often caused by the parasite Theileria equi. We applied competitive ELISA (cELISA) and nested PCR diagnostic methods to detect this parasite in horses by screening 162 samples from mainland Portugal where the parasite is endemic, and 143 from the Azores representing both native and imported horse populations. We found that 2.8% of the Azorean samples tested positive exclusively by cELISA, 1.4% tested positive only by nested PCR, and 9.1% tested positive using both tests. Samples from the native Terceira Pony population were negativ...
Yao H, Osterrieder N, O'Callaghan DJ.The EICP0 gene (gene 63) of equine herpesvirus 1 (EHV-1) encodes an early regulatory protein that is a promiscuous trans-activator of all classes of viral genes. Bacterial artificial chromosome (BAC) technology and RecE/T cloning were employed to delete the EICP0 gene from EHV-1 strain KyA. Polymerase chain reaction, Southern blot analysis, and DNA sequencing confirmed the deletion of the EICP0 gene and its replacement with a kanamycin resistance gene in mutant KyA. Transfection of rabbit kidney cells with the EICP0 mutant genome produced infectious virus, indicating that the EICP0 gene is not...
Pusterla N, Mapes S, Johnson C, Slovis N, Page A, Gebhart C.The purpose of the current study was to compare the molecular detection rate of Lawsonia intracellularis between feces and rectal swabs collected from 42 foals with suspected equine proliferative enteropathy (EPE). Fecal samples and rectal swabs were processed for DNA purification by using an automated extraction system. The purified DNA was then analyzed by real-time polymerase chain reaction (PCR) for the presence of the aspartate ammonia lyase (aspA) gene of L. intracellularis. Absolute quantitation was calculated by using a standard curve for L. intracellularis and expressed as copy number...
Knight CG, Munday JS, Rosa BV, Kiupel M.A 9-year-old gelding presented with approximately 100 papillomas that covered about 75% of the distal penis. Biopsy was performed, and histology showed evidence of viral cytopathic change and koilocytosis. Polymerase chain reaction using DNA extracted from biopsied tissue amplified equine papillomavirus type 2 (EcPV-2) DNA sequences. Sixteen months later, the horse was re-examined and the appearance of the papillomas was unchanged. Equine papillomavirus type 2 DNA sequences were again amplified from both biopsied tissue and swabs of the penis. Papillomavirus was localized to the lesions by imm...
Weyer CT, Grewar JD, Burger P, Joone C, Lourens C, MacLachlan NJ, Guthrie AJ.African horse sickness (AHS) is a fatal disease of equids relevant to the global equine industry. Detection of AHS virus (AHSV) during outbreaks has become more rapid and efficient with the advent of group specific reverse transcriptase quantitative polymerase chain reaction (GS RT-qPCR) assays to detect AHSV nucleic acid. Use of GS RT-qPCR together with recently described type specific (TS RT-qPCR) assays cannot only expedite diagnosis of AHS but also facilitate further evaluation of the dynamics of AHSV infection in the equine host. A potential limitation to the application of these assays i...
Löhr CV, Juan-Sallés C, Rosas-Rosas A, Parás García A, Garner MM, Teifke JP.Sarcoids were diagnosed in two captive zebras from different facilities. Zebra 1 (Equus burchellii boehmi) was a 4.5-yr-old, captive-born male that presented with a 9- by 7-cm inguinal mass. Seven months after surgical excision of the inguinal mass, the zebra presented with a similar lesion in the right upper eyelid that has relapsed repeatedly and has not responded to treatment including local cisplatin injections and cryosurgery. Zebra 2 (of undetermined taxon) was housed at a private wild animal farm. The zebra presented with a single, raised, 2.5- by 2.0- by 2.0-cm, ulcerated mass on the n...
Temesgen T, Getachew Y, Negussie H.Equine herpesvirus (EHV) infections have major economic, health, and welfare impacts on equids. This study was performed in three selected zones of central Ethiopia with the objectives of detecting EHV-1, -2, and -5 in horses and donkeys with suggestive signs of respiratory tract disease and to assess epidemiological risk factors associated with infections. Methods: A total of 58 nasopharyngeal swab samples were collected from donkeys and horses showing clinical signs of respiratory disease. Polymerase chain reaction (PCR) was used to detect EHV-1, -2, and -5. Evaluation of the associated risk...
Battsetseg B, Lucero S, Xuan X, Claveria F, Byambaa B, Battur B, Boldbaatar D, Batsukh Z, Khaliunaa T, Battsetseg G, Igarashi I, Nagasawa H....Babesia equi (EMA-1) and Babesia caballi (BC48) gene fragments were amplified by polymerase chain reaction (PCR), in blood samples, and partially fed-females and egg and larval progenies of Dermacentor nuttalli, collected from horses in Altanbulag, Tuv Province, Mongolia. While Babesia parasite DNA was detected in some horse blood samples during the first PCR, all positive cases in partially fed-female ticks, eggs and larvae were confirmed by nested PCR. Present study reinforces earlier similar findings in unfed D. nuttalli ticks collected from an open space vegetation in Bayanonjuul, Tuv Prov...
Walter J, Balzer HJ, Seeh C, Fey K, Bleul U, Osterrieder N.Equid herpesvirus 1 (EHV-1) is a highly prevalent pathogen in horse populations worldwide. Oronasal infection represents the classic route of disease transmission. Venereal shedding of EHV-1 is not regarded relevant in terms of virus spreading, which is in contrast to the close relatives of EHV-1, bovine and suid alphaherpesvirus, for which artificial insemination is a well-documented and accepted means of virus spread. Objective: Documentation of venereal EHV-1 shedding in 3 naturally infected stallions. Methods: Three stallions were infected during an acute outbreak by an EHV-1 strain with t...
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...
Phetkarl T, Fungwithaya P, Udompornprasith S, Amendt J, Sontigun N. and tabanid flies are of medical and veterinary importance because they play crucial roles in disease transmission as mechanical vectors of various hemopathogens. However, its role as a hemoprotozoan parasite vector in horse farms has not been studied. Therefore, we investigated the occurrence of hemoprotozoan parasites belonging to the genera , , and in and tabanid flies using conventional polymerase chain reaction (PCR) and DNA sequencing. Unassigned: All samples ( and tabanid flies) were collected using an Nzi trap for three consecutive days each month from November 2022 to March 2023. T...
Tartor YH, Hamad MH, Abouzeid NZ, El-Belkemy FA.Equine pythiosis is an emerging, devastating disease that is hard to treat. The tumour-like nodular skin masses grow rapidly and the outcome is generally fatal, and thus early diagnosis and intervention are important. Objective: (i) To highlight the clinical, histological and haematological findings in pythiosis, and (ii) to evaluate the efficacy of direct sample multiplex-PCR targeting the single nucleotide polymorphisms within the ribosomal DNA region for detection and genotyping of Pythium insidiosum. Methods: Two hundred and twenty horses including 204 Arabian and 16 draft horses were surv...
Camino E, Cruz-Lopez F, de Juan L, Dominguez L, Shiels B, Coultous RM.The intraerythrocytic protozoans Theileria equi and Babesia caballi are the causative agents of equine piroplasmosis (EP), one of the most important equine tick-borne diseases due to its significant impact on global international horse trade. Although EP is known to be endemic in Spain, previous phylogenetic studies have only been conducted for limited geographical regions. Therefore, the objective of this study was to evaluate the genetic diversity and distribution of these parasite species nationwide. This was performed by amplification of the 18S small subunit (SSU) rRNA gene from 100 EP ...
Silva MA, Silva KM, Jesus AL, Barros LO, Corteggio A, Altamura G, Borzacchiello G, Freitas AC.Papillomavirus (PV) are double-stranded DNA viruses that can cause both benignant and malignant tumours in mammals. Twelve genotypes of bovine papillomavirus (BPV1-12) have been identified so far. The presence of BPV1 and 2 has been found in the body fluids of cattle and horses. The aim of this study is to investigate the presence of BPV DNA and the expression of viral genes in the blood and sperm cells of healthy horses using PCR and RT-PCR. BPV-1 or 2 was detected in 14 of 70 blood samples (20%) and in 11 of 31 semen samples (35%). In five of fourteen blood samples, the E5 expression tested ...
de Leon PM, Campos VF, Dellagostin OA, Deschamps JC, Seixas FK, Collares T.In this study, polymerase chain reaction (PCR) reamplification of the first PCR product (2nd-PCR) and a qPCR assay were used to detect the sex determining region Y (SRY) gene from circulating cell-free fetal DNA (ccffDNA) in blood plasma of pregnant mares to determine fetal sex. The ccffDNA was isolated from plasma of 20 Thoroughbred mares (5-13 y old) in the final 3 mo of pregnancy (fetal sex was verified after foaling). For controls, plasma from two non-pregnant mares and two virgin mares were used, in addition to the non-template control. The 182 bp nucleotide sequence corresponding to the ...
Herrera C, Morikawa MI, Bello MB, von Meyeren M, Centeno JE, Dufourq P, Martinez MM, Llorente J.Preimplantation genetic diagnosis (PGD) allows identifying genetic traits in early embryos. Because in some equine breeds, like Polo Argentino, females are preferred to males for competition, PGD can be used to determine the gender of the embryo before transfer and thus allow the production of only female pregnancies. This procedure could have a great impact on commercial embryo production programs. The present study was conducted to adapt gender selection by PGD to a large-scale equine embryo transfer program. To achieve this, we studied (i) the effect on pregnancy rates of holding biopsied e...
Sharma PC, Cullinane AA, Onions DE, Nicolson L.The polymerase chain reaction (PCR) is a sensitive technique used to detect DNA of viral pathogens. We have applied the technique to the detection of Equid herpesviruses-1 and -4 (EHV-1 and EHV-4) DNA within nasopharyngeal swab samples from horses. Ninety-eight samples from suspected field cases and in-contact horses were analysed. The assays were conducted blind and later decoded and compared with virus isolation data. Our results indicate that PCR is a sensitive and rapid technique for the diagnosis of EHV-1 and EHV-4 infection.
Zimmermann W, Dürrwald R, Ludwig H.Borna disease virus in naturally infected horses, a donkey and sheep was detected for the first time by amplification of viral RNA using PCR. In contrast to a control group of healthy horses, brain tissue was positive by this assay in all animals with neurological symptoms. The use of a second round of PCR with nested primers following Southern hybridization confirmed the specificity and increased the sensitivity of the test. Comparison with conventional methods recommends this technique for monitoring of BDV infections at a molecular level.
Raftery AG, Jallow S, Rodgers J, Sutton DGM.Globally, working equines have a continued and growing socioeconomic role in supporting the livelihoods of between 300-600 million people in low income countries which is rarely recognised at a national or international level. Infectious diseases have significant impact on welfare and productivity in this population and equine trypanosomiasis is a priority disease due to its severity and prevalence. Strategies are required to improve the prevention, diagnosis, management and treatment of trypanosomiasis in equines and more data are required on the efficacy and safety of current trypanocidal dr...
Koblischke P, Kindahl H, Budik S, Aurich J, Palm F, Walter I, Kolodziejek J, Nowotny N, Hoppen HO, Aurich C.We tested the hypothesis that subclinical endometritis occurs after embryo transfer (ET) in the horse. Recipient mares were treated with meclofenamic acid (M) or flunixin meglumin (F) after ET or were left untreated (n=9 per group). Embryos were re-collected 4 days after transfer. Endometrial biopsies were taken for histology and analysis of cyclooxygenase-2 (COX-2) by immunohistochemistry and for PCR. Bacteriological swabs were collected from the uterus and lavage fluid of donor and recipient mares. Progesterone and prostaglandin F(2alpha) release was analysed in recipient mares after ET. Fou...
