Infectious diseases in horses encompass a range of illnesses caused by bacteria, viruses, fungi, or parasites. These diseases can affect various systems within the equine body, leading to symptoms that range from mild discomfort to severe systemic illness. Common infectious diseases in horses include equine influenza, strangles, equine herpesvirus, and West Nile virus. These diseases can be transmitted through direct contact with infected animals, contaminated surfaces, or vectors such as insects. Understanding the mechanisms of transmission, pathogenesis, and immune response is essential for effective prevention and control. This page compiles peer-reviewed research studies and scholarly articles that explore the epidemiology, diagnosis, treatment, and management of infectious diseases in horses.
Lee H, Yun SH, Hyon JY, Lee SY, Yi YS, Choi CW, Jun S, Park EC, Kim SI.Streptococcus equi subspecies equi is a pathogenic bacterium that causes strangles, a highly contagious respiratory infection in horses and other equines. The limitations of current vaccines against S. equi infection warrants the development of an affordable, safe, and effective vaccine. Because gram-positive extracellular vesicles (EVs) transport various immunogenic antigens, they are attractive vaccine candidates. Here, we purified the EVs of S. equi ATCC 39506 and evaluated them as a vaccine candidate against S. equi infection in mice. As an initial step, comparative proteomic analysis was ...
Spence KL, Rosanowski SM, Slater J, Cardwell JM.Exotic diseases pose a significant risk to horse health and welfare. Several stakeholder groups, including primary care veterinarians, share responsibility for maintaining freedom from pathogens that cause exotic diseases. However, little is known about the current state of exotic disease preparedness within the British horse industry. Objective: The aim of this study was to explore equine veterinarians' experiences of, and attitudes towards, exotic disease preparedness in Great Britain. Methods: This is a qualitative interview-based study. Methods: Semistructured interviews were conducted wit...
Pellizzoni SG, Costa SCL, Mery RBG, Barbieri JM, Munhoz AD, Silva AND, Sevá ADP, Alvarez MRDV, Albuquerque GR.The aims of this study were to determine the seroprevalence of Sarcocystis neurona antibodies in equines in the Ilhéus-Itabuna microregion (BA), and identify possible factors associated with infection. The presence of sporocysts/oocysts of Sarcocystis spp. was also verified in Didelphis spp. A total of 669 serum samples were collected from equines in 56 properties located in 12 municipalities in the region. Indirect fluorescent antibody test was performed with slides containing merozoites of the S. neurona, using a cut-off titer of 1:80. Occurrence of 7.92% of anti-S. neurona antibodies was o...
Bělková T, Bártová E, Řičařová D, Jahn P, Jandová V, Modrý D, Hrazdilová K, Sedlák K.Theileria equi and Babesia caballi are protozoan agents causing equine piroplasmosis, endemic in countries all over the world. The aim of this study was to detect antibodies to T. equi and B. caballi in horses in the Czech Republic and to investigate the origin of the infection. Blood sera from 711 horses were examined with competitive enzyme-linked immunosorbent assay; positive samples were verified with indirect fluorescence immunoassay. Antibodies to T. equi and B. caballi were detected in eight (1.1%) and three (0.4%) horses, respectively. Infection with T. equi was confirmed by PCR and se...
Barrett RS, Wiethoelter A, Halpin K.To elucidate veterinarians' and horse owners' perceptions towards the use of Hendra virus (HeV) antibody titre testing and how it influences veterinary advice. Methods: Six semi-structured phone interviews were conducted with veterinarians who have submitted samples for HeV antibody titre testing. Interviews were recorded, transcribed and thematically analysed to identify and report common themes within the data. Results: Veterinarians are predominantly using the titre tests as an alternative to vaccination due to clients' fear of vaccine reactions. The high cost of titre testing, the difficul...
Mayo CE, Weyer CT, Carpenter MJ, Reed KJ, Rodgers CP, Lovett KM, Guthrie AJ, Mullens BA, Barker CM, Reisen WK, MacLachlan NJ.The availability of rapid, highly sensitive and specific molecular and serologic diagnostic assays, such as competitive enzyme-linked immunosorbent assay (cELISA), has expedited the diagnosis of emerging transboundary animal diseases, including bluetongue (BT) and African horse sickness (AHS), and facilitated more thorough characterisation of their epidemiology. The development of assays based on real-time, reverse-transcription polymerase chain reaction (RT-PCR) to detect and identify the numerous serotypes of BT virus (BTV) and AHS virus (AHSV) has aided in-depth studies of the epidemiology ...
April Lawson and Gina Pinchbeck of the University of Liverpool introduce a new initiative that will use electronic health records to create an evidence base for equine research and surveillance.
West Nile Virus (WNV) is a mosquito-borne virus enzootically maintained in birds. However, it can incidentally infect other species, leading to sometimes severe clinical consequences like in horses and especially human beings. Despite the topic relevance, the presence and distribution of WNV are currently unknown in Namibia. Several countries implement surveillance systems based on virus detection in birds, mosquitoes, and vertebrate species including horses. The present study aimed to fill this knowledge gap by serologically evaluating WNV exposure in Namibian donkeys, whose population is rem...
Othman AA, Hiblu MA, Abbassi MS, Abouzeed YM, Ahmed MO.The present study investigated the colonization rates and antimicrobial susceptibility of Staphylococcus species isolated from the nostrils of healthy horses. A nonselective laboratory approach was applied, followed by confirmation using a Phoenix automated microbiological system. Among the 92 horses included in the study, 48.9% (45/92) carried Staphylococcus species of mostly the coagulase-negative staphylococci (CoNS) type yielding 70 Staphylococcus strains. Of these strains, 37.1% (26/70; 24 CoNS and 2 coagulase-positive staphylococci; CoPS) were identified as methicillin-resistant staphylo...
de Siqueira SM, da Costa Maia R, do Nascimento Ramos V, da Silva Rodrigues V, Szabó MPJ.We herein describe zebuine cattle tick infestation in a farm in southeast Brazil with an examination accurate enough to detect tick immatures and species other than R. microplus. Cattle were inspected monthly for ticks from May 2015 to May 2017 and 7604 ticks were collected along 276 bovine inspections. Rhipicephalus microplus was the dominant species (7197 specimens, 94.5% from the total), but Amblyomma sculptum was also collected (407/5.5%). Horse tick infestations were evaluated for comparison purposes of A. sculptum infestations of a primary host sharing pastures with bovines. Ticks were c...
Molla AM, Fentahun T, Jemberu WT.Epizootic lymphangitis (EL) is a chronic, contagious, fungal disease of equids. The disease is highly prevalent in cart pulling equines of Ethiopia affecting the livelihood of the cart owning households and welfare of the cart animals. This study estimated the economic impacts of EL and assessed cart owners' knowledge and practices related to the disease in northwest Ethiopia. A multistage cluster sampling approach was implemented to select cart animal owners for the study. A total of 274 cart animal owners were interviewed to collect data for the study. The average annual economic loss per ca...
Tanaka Y, Suganuma K, Watanabe K, Kobayashi Y.Dourine, caused by infection with Trypanosoma equiperdum, is one of the trypanosomiasis in equids. The clinical course of dourine is long-term, ranging from 1-2 months to several years. Since the pathogenesis of dourine has not yet been elucidated, experimental studies using mouse infection models are needed. Although mice are not susceptible to most T. equiperdum strains, some strains can infect mice. Even in such strains, infected mice develop rapidly transient parasitemia and die within 2-8 days. Therefore, mice experimentally infected with these T. equiperdum strains are not suitable for m...
Morris ERA, Boyle AG, Riihimäki M, Aspán A, Anis E, Hillhouse AE, Ivanov I, Bordin AI, Pringle J, Cohen ND.Streptococcus equi subsp. equi (SEE) is a host-restricted bacterium that causes the common infectious upper respiratory disease known as strangles in horses. Perpetuation of SEE infection appears attributable to inapparent carrier horses because it neither persists long-term in the environment nor infects other host mammals or vectors, and infection results in short-lived immunity. Whether pathogen factors enable SEE to remain in horses without causing clinical signs remains poorly understood. Thus, our objective was to use next-generation sequencing technologies to characterize the genome, me...
Pusterla N, Barnum S, Miller J, Varnell S, Dallap-Schaer B, Aceto H, Simeone A.Here we report on an EHV-1 outbreak investigation caused by a novel genotype H752 (histidine in amino acid position 752 of the ORF 30 gene). The outbreak involved 31 performance horses. Horses were monitored over a period of 35 days for clinical signs, therapeutic outcome and qPCR results of EHV-1 in blood and nasal secretions. The morbidity of the EHV-1 outbreak was 84% with 26 clinically infected horses displaying fever and less frequently anorexia and distal limb edema. Four horses showed mild transient neurological deficits. Clinically diseased horses experienced high viral load of EHV-1 i...
Fu DJ, Ramachandran A, Miller C.A 3-y-old, female Quarter Horse with a history of acute neurologic signs was found dead and was submitted for postmortem examination. Areas of petechial and ecchymotic hemorrhage were present on cross-sections of the cerebrum, cerebellum, and brainstem. Histologic examination of the brain revealed severe, purulent meningoencephalitis and vasculitis with a myriad of intralesional gram-positive cocci. was identified from formalin-fixed, paraffin-embedded tissue obtained from sites with active lesions by PCR and nucleotide sequencing of bacterial 16S ribosomal RNA. should be considered as a cau...
Paz GSD, Camargo GG, Cury JE, Apolonio EVP, Garces HG, Prado ACD, Chechi JL, Oliveira AL, Watanabe MJ, Bagagli E, Bosco SMG.Pythiosis is a disease caused by the oomycete Pythium insidiosum, mainly reported in equines, dogs and humans and directly transmitted through contaminant zoospores in aquatic environments. We report the first outbreak of equine pythiosis in five equines. Wound samples were submitted for diagnostic testing including mycological culture and nested PCR. Treatment approaches consisted of conventional and alternative therapies. Microbiological analyses were performed using water samples from the riverbanks close to where the animals had grazed. All animals were positive for P. insidiosum cultures...
Zarski LM, Vaala WE, Barnett DC, Bain FT, Soboll Hussey G.Equine herpesvirus 1 (EHV-1) ubiquitously infects horses worldwide and causes respiratory disease, abortion, and equine herpesvirus myeloencephalopathy. Protection against EHV-1 disease is elusive due to establishment of latency and immune-modulatory features of the virus. These include the modulation of interferons, cytokines, chemokines, antigen presentation, and cellular immunity. Because the modulation of immunity likely occurs at the site of first infection-the respiratory epithelium, we hypothesized that the mucosal influenza vaccine Flu Avert I.N. (Flu Avert), which is known to stimulat...
Subbiah M, Thirumalapura N, Thompson D, Kuchipudi SV, Jayarao B, Tewari D.Metagenomic sequencing of clinical diagnostic specimens has a potential for unbiased detection of infectious agents, diagnosis of polymicrobial infections and discovery of emerging pathogens. Herein, next generation sequencing (NGS)-based metagenomic approach was used to investigate the cause of illness in a subset of horses recruited for a tick-borne disease surveillance study during 2017-2019. Blood samples collected from 10 horses with suspected tick-borne infection and five apparently healthy horses were subjected to metagenomic analysis. Total genomic DNA extracted from the blood samples ...
Nielsen MK, Facison C, Scare JA, Martin AN, Gravatte HS, Steuer AE.Strongylus vulgaris is the most pathogenic intestinal helminth parasite infecting horses. The migrating larvae in the mesenteric blood vessels can cause non-strangulating intestinal infarctions, which have a guarded prognosis for survival. Infections are typically diagnosed by coproculture, but a PCR test is available in some countries. While it is ideal to test horses individually, many veterinarians and clients wish to pool samples to reduce workload and cost of the diagnostic method. The purpose of this study was to determine if pooling of fecal samples would negatively impact diagnostic pe...
Chen X, Zhao Y, Su L, Wang L, Ma X, Zhang B, Su Y.Strangles, which is caused by Streptococcus equi subspecies equi, is one of the most prevalent equine infectious diseases and poses heavy economic losses worldwide. Although various vaccines have been used for decades, they seemed to be sub-optimal to demonstrate effective protection, and the antigen component of vaccines against S. equi remains to be optimized. In the present study, three target antigens (M-like protein, α2-macroglobulin and IgG-binding protein, and glyceraldehyde-3-phosphate dehydrogenase) were selected and expressed. Mice were immunized and challenged, and their immune res...
Torres R, Hurtado C, Pérez-Macchi S, Bittencourt P, Freschi C, de Mello VVC, Machado RZ, André MR, Müller A.This study aimed to serologically and molecularly survey and in thoroughbred horses from racecourses in Chile. Additionally, the genetic diversity of the positive samples was assessed. A total of 286 thoroughbred horses from the Santiago and Valparaíso racecourses had their serum samples submitted to an ELISA for and , and 457 samples (from the Santiago, Valparaíso, and Concepción racecourses) were tested with nested PCRs for the 48 KDa rhoptry protein (RAP-1) and 18S rRNA genes. Selected RAP-1 and 18S positive products were sequenced to perform phylogenetic and haplotype analyses. An ...
Onyiche TE, Sivakumar T, Tuvshintulga B, Nugraha AB, Ahedor B, Mofokeng L, Luka J, Mohammed A, Mbaya AW, Biu AA, Yokoyama N, Thekisoe O.Equine piroplasmosis is caused by apicomplexan parasites, namely, and , which are transmitted to equids principally through ticks. To ascertain the exposure of equines to agents of equine piroplasms, we tested serum samples collected from horses (n = 272) and donkeys (n = 170) in North-Western Nigeria for the presence of antibodies against and using IFAT and ELISA. The seroprevalence of in the horses determined using IFAT and ELISA was 48.89% and 45.96%, respectively, while for , it was 6.3% and 0.4%, respectively. For , the seroprevalence based on IFAT and ELISA results in donkeys was...
Samoilowa S, Giessler KS, Torres CEM, Hussey GS, Allum A, Fux R, Jerke C, Kiupel M, Matiasek K, Sledge DG, Goehring LS.Equid herpesvirus-1 (EHV-1) causes respiratory disease, abortion and myeloencephalopathy in horses worldwide. As member of the , latency is key to EHV-1 epidemiology. EHV-1 latent infection has been detected in the trigeminal ganglion (TG), respiratory associated lymphoid tissue (RALT) and peripheral blood mononuclear cells (PBMC) but additional locations are likely. The aim of this study was to investigate the distribution of viral DNA throughout the equine body. Twenty-five horses divided into three groups were experimentally infected via intranasal instillation with one of three EHV-1 virus...
Liu J, Zhang Z, Bai A, Sha Y, Ma L, Qin S, Chen F, Qin S, Wu J.Feline parvovirus (FPV), a type of parvovirus prevalent worldwide, can cause foetal death and acute enteritis in adult cats with severe leukopenia, and yet there are no effective drugs to prevent or treat FPV. Here, the immune effects of two FPV vaccines on horses were compared. IgG was extracted from FPV-immunized horse sera. Equine F(ab') fragments were obtained from pepsin-digested IgG and then purified by protein-G column chromatography. The results showed that the inactivated FPV oil vaccine was more effective than the inactivated FPV propolis vaccine in helping healthy horses to produce ...
Nielsen SS, Bicout DJ, Calistri P, Canali E, Drewe JA, Garin-Bastuji B, Gonzales Rojas JL, Gortazar Schmidt C, Herskin M, Michel V, Miranda Chueca MA....The European Commission requested EFSA assess antimicrobial-resistant bacteria responsible for animal transmissible diseases, with a view to listing such pathogens for European Union action. This Scientific Opinion addresses the ad hoc method developed: (i) to give a global state of play as regards resistant animal pathogens that cause transmissible animal diseases, (ii) to identify the most relevant bacteria in the EU and (iii) to summarise their actual or potential animal health impact, and to perform their assessment for being listed and categorised according to the criteria of Articles 7, ...
Dionísio L, Medeiros F, Pequito M, Faustino-Rocha AI.Influenza is an extremely contagious respiratory disease, which predominantly affects the upper respiratory tract. There are four types of influenza virus, and pigs and chickens are considered two key reservoirs of this virus. Equine influenza (EI) virus was first identified in horses in 1956, in Prague. The influenza A viruses responsible for EI are H7N7 and H3N8. Outbreaks of EI are characterized by their visible and rapid spread, and it has been possible to isolate and characterize H3N8 outbreaks in several countries. The clinical diagnosis of this disease is based on the clinical signs pre...
Zendri F, Isgren CM, Sinovich M, Richards-Rios P, Hopkins KL, Russell K, Groves N, Litt D, Fry NK, Timofte D. () may cause diphtheria in humans and can be carried by a wide range of animal species including dairy cows and, more recently, dogs and cats that have been increasingly involved in zoonotic trasmission. We isolated and characterized, by WGS, a toxigenic strain from a diseased horse in the United Kingdom showing clinical signs of respiratory diphtheria comparable to those seen in people. Our results indicate a role for horses as reservoirs for zoonotic .
Wasiński B, Paschalis-Trela K, Trela J, Czopowicz M, Kita J, Żychska M, Cywińska A, Markowska-Daniel I, Carter C, Witkowski L.Leptospirosis is one of the most common zoonotic infections worldwide, including in most livestock, some companion animals, horses, wildlife, and humans. Epidemiological estimation of its prevalence in all species is difficult due to the variety of clinical presentations and challenges regarding laboratory diagnosis. The purpose of this study was to measure the seroprevalence of leptospiral infection in Arabian horses kept in the largest breeding farms in Poland, representing over 15% of the Polish Arabian horse population. Leptospira antibodies were detected by MAT (cut-off 1:100) in 33.2% of...
Nielsen SS, Bicout DJ, Calistri P, Canali E, Drewe JA, Garin-Bastuji B, Gonzales Rojas JL, Gortazar Schmidt C, Herskin M, Michel V, Miranda Chueca MA....The European Commission requested EFSA assess antimicrobial-resistant bacteria responsible for animal transmissible diseases, with a view to listing such pathogens for European Union action. This Scientific Opinion addresses the ad hoc method developed: (i) to give a global state of play as regards resistant animal pathogens that cause transmissible animal diseases, (ii) to identify the most relevant bacteria in the EU and (iii) to summarise their actual or potential animal health impact, and to perform their assessment for being listed and categorised according to the criteria of Articles 7, ...
Mitchell CJ, Monath TP, Sabattini MS, Daffner JF, Cropp CB, Calisher CH, Darsie RF, Jakob WL.Mosquitoes were collected in Santa Fe and Rio Negro provinces, Argentina, in 1982-1983 during a western equine encephalitis (WEE) epizootic. Totals of 153,084 mosquitoes from Santa Fe Province and 484 from Rio Negro Province were tested for virus in 2,351 pools. Seventeen virus strains were isolated, all from Santa Fe collections, as follows: 4 WEE, 6 Venezuelan equine encephalitis, 1 St. Louis encephalitis, 2 Antequera, 1 Maguari, 1 Melao, 1 new vesiculovirus (Calchaqui), and 1 Gamboa. The WEE virus isolates were from Aedes albifasciatus, Anopheles albitarsis, Mansonia species, and Psorophora...
Hammond SA, Raabe ML, Issel CJ, Montelaro RC.We previously demonstrated in trials of a variety of experimental vaccines to equine infectious anemia virus (EIAV) a remarkable spectrum of efficacy ranging from sterilizing protection to severe enhancement of virus replication and disease, depending on the immunization strategy used. This range of vaccine efficacy observed in vivo offers a unique opportunity for evaluating potential in vitro immune correlates of protection and enhancement. We describe here a comprehensive analysis and comparison of EIAV envelope-specific antibody responses elicited by attenuated, inactivated whole virus and ...
van Balen J, Mowery J, Piraino-Sandoval M, Nava-Hoet RC, Kohn C, Hoet AE.The role that environmental contamination might play as a reservoir and a possible source of Methicillin-resistant Staphylococcus aureus (MRSA) for patients and personnel at equine veterinary hospitals remains undefined, as the environment has only been monitored during outbreaks or for short periods. Therefore, the objectives of this study were to determine the monthly presence, distribution, and characteristics of environmental MRSA at an equine hospital, and to establish patterns of contamination over time using molecular epidemiological analyses. For this purpose, a yearlong active MRSA su...
Kojima K, Taniguchi K, Kobayashi N.We have sequenced gene 5 encoding NSP1 for three human, two porcine, two bovine, one feline, and five equine rotavirus strains, and compared the nucleotide and deduced amino acid sequences with the published sequences for other various strains. Subgroup I human strains L26, 69M, and DS-1 were found to have a similar NSP1 sequence despite their different G serotypes, VP4 genotypes, and RNA patterns. The NSP1 sequence of the human strain K8 showed a high degree of homology to those of porcine strains OSU and YM. A high degree of homology was found among three equine strains (H2, FI-14, and FI23)...
Scholz HC, Pearson T, Hornstra H, Projahn M, Terzioglu R, Wernery R, Georgi E, Riehm JM, Wagner DM, Keim PS, Joseph M, Johnson B, Kinne J, Jose S....Glanders, caused by the gram-negative bacterium Burkholderia mallei, is a highly infectious zoonotic disease of solipeds causing severe disease in animals and men. Although eradicated from many Western countries, it recently emerged in Asia, the Middle-East, Africa, and South America. Due to its rareness, little is known about outbreak dynamics of the disease and its epidemiology. Results: We investigated a recent outbreak of glanders in Bahrain by applying high resolution genotyping (multiple locus variable number of tandem repeats, MLVA) and comparative whole genome sequencing to B. mallei i...
Savu AN, Schoenbrunner AR, Politi R, Janis JE.Animal bites are common worldwide. Due to the plethora of animals, there are diverse pathogens with specific associated risks and treatment algorithms. It is crucial to understand these to develop and execute appropriate management plans. This practical review was designed to amalgamate the most common bites worldwide and synthesize data to help guide treatment plans. Methods: A PubMed literature search was performed focusing on the major animal bites. High-level studies were preferred and analyzed but lower-level studies were also used if high-level studies did not exist. Results: The tables ...
Ruzauskas M, Siugzdiniene R, Klimiene I, Virgailis M, Mockeliunas R, Vaskeviciute L, Zienius D.Among coagulase-negative staphylococci, Staphylococcus haemolyticus is the second most frequently isolated species from human blood cultures and has the highest level of antimicrobial resistance. This species has zoonotic character and is prevalent both in humans and animals. Recent studies have indicated that methicillin-resistant S. haemolyticus (MRSH) is one of the most frequent isolated Staphylococcus species among neonates in intensive care units. The aim of this study was to determine the presence of MRSH in different groups of companion animals and to characterize isolates according the...
Passamonti F, Veronesi F, Cappelli K, Capomaccio S, Coppola G, Marenzoni ML, Piergili FD, Verini SA, Coletti M.Anaplasma phagocytophilum, the causative agent of granulocytic ehrlichiosis, affects several species of wild and domesticated mammals, including horses. In this work we compared direct and indirect methods to evaluate A. phagocytophilum presence in Central Italy: 135 sera were screened by IFA for A. phagocytophilum and other haemopathogens (Theileria equi and Babesia caballi). Each horse was also tested for A. phagocytophilum 16S rRNA with a nested-PCR technique. In order to examine the risk of A. phagocytophilum transmission, 114 ticks were examined for the presence of A. phagocytophilum by P...
Provitera P, Bouamr F, Murray D, Carter C, Scarlata S.Human immunodeficiency virus (HIV) and equine infectious anemia virus (EIAV) are closely related lentiviruses that infect immune cells, but their pathogenesis differ. Localization to the cytosolic leaflet of the plasma membrane is critical for replication of both viruses. This localization is accomplished through the matrix (MA) domain of the Gag precursor protein. In HIV-1, association of MA to anionic membranes appears to be primarily driven by a linear cluster of basic residues in the MA domain and an N-myristoylation signal. Interestingly, the MA protein of EIAV does not contain either of ...
Nagata K, Tsukita S, Tamura T, Sone N.A Helicobacter pylori membrane fraction oxidized yeast and equine cytochrome c, and N,N,N',N'-tetramethyl-p-phenylenediamine (TMPD). When ascorbate was used as reductant, the Vmax and apparent Km values were 612 nmol electron min-1 (mg protein)-1 and 14 microM for yeast, and 419 nmol electron min-1 (mg protein)-1 and 19 microM for equine cytochrome c, respectively. For TMPD oxidation, the Vmax and Km values were 640 nmol electron min-1 (mg protein)-1 and 182 microM, respectively. These oxidase activities showed a high affinity for oxygen. Inhibition of both cytochrome-c and TMPD oxidase activi...
Frey J.RTX toxins are bacterial pore-forming toxins that are particularly abundant among pathogenic species of Pasteurellaceae, in which they play a major role in virulence. RTX toxins of several primary pathogens of the family of Pasteurellaceae are directly involved in causing necrotic lesions in the target organs. Many RTX toxins are known as haemolysins because they lyse erythrocytes in vitro, an effect that is non-specific, but which serves as a useful marker in bacteriological identification and as an easily measurable signal in vitro in experimental studies. More recent studies have shown that...
Rossi SL, Guerbois M, Gorchakov R, Plante KS, Forrester NL, Weaver SC.Venezuelan equine encephalitis virus (VEEV) is an arbovirus that causes periodic outbreaks that impact equine and human populations in the Americas. One of the VEEV subtypes located in Mexico and Central America (IE) has recently been recognized as an important cause of equine disease and death, and human exposure also appears to be widespread. Here, we describe the use of an Internal Ribosome Entry Site (IRES) from encephalomyocarditis virus to stably attenuate VEEV, creating a vaccine candidate independent of unstable point mutations. Mice infected with this virus produced antibodies and wer...
Cullinane AA, Rixon FJ, Davison AJ.The genome structure of equine herpesvirus 1 (EHV-1) subtype 2 was shown by electron microscopic studies and restriction endonuclease site mapping to comprise two covalently linked segments (L, 109 kbp; S, 35 kbp). The S segment contains a unique sequence (US) flanked by a substantial inverted repeat (TRS/IRS). Thus, the genome structure of EHV-1 subtype 2 is similar to that published previously for EHV-1 subtype 1, but the two subtypes differ in the occurrences of EcoRI and BamHI restriction sites. Hybridization studies using cloned EHV-1 DNA showed that the genome of EHV-1 subtype 2 is colin...
Gohari IM, Arroyo L, Macinnes JI, Timoney JF, Parreira VR, Prescott JF.Up to 60% of cases of equine colitis have no known cause. To improve understanding of the causes of acute colitis in horses, we hypothesized that Clostridium perfringens producing enterotoxin (CPE) and/or beta2 toxin (CPB2) are common and important causes of severe colitis in horses and/or that C. perfringens producing an as-yet-undescribed cytotoxin may also cause colitis in horses. Fecal samples from 55 horses (43 adults, 12 foals) with clinical evidence of colitis were evaluated by culture for the presence of Clostridium difficile, C. perfringens, and Salmonella. Feces were also examined by...
Wang T, Hu L, Wang Y, Liu W, Liu G, Zhu M, Zhang W, Wang C, Ren H, Li L.Equine herpesvirus-8 (EHV-8) is one of the most economically significant viruses that infect mammals of the genus Equus worldwide, which cause severe respiratory diseases and abortion in horses. However, there is no report of abortion caused by EHV-8 in donkeys. The present case report is about a 4-year-old donkey having an abortion and showing a serious respiratory issue on the 296th day of pregnancy. Bacteriological and molecular tests were used to screen possible bacterial/viral pathogens to detect the etiological agent. Salmonella abortus equi, EHV-1, EHV-4, and EAV were all negative in th...
Ereqat S, Nasereddin A, Al-Jawabreh A, Al-Jawabreh H, Al-Laham N, Abdeen Z.Trypanosoma evansi is the causative agent of surra, a disease that occurs in many animal species. The disease is responsible for substantial losses in global production and can be fatal if not diagnosed early. This study aims to determine the prevalence of T. evansi in livestock, equids and dromedary camels in Palestine. Methods: Blood samples were collected during 2015-2017 from domesticated animals (n = 259 animals; 77% females and 23% males) including camels (n = 87), horses (n = 46), donkeys (n = 28), mules (n = 2), sheep (n = 49) and goats (n = 48) from eight districts: Ariha (Jericho), N...
Landolt GA.For decades the horse has been viewed as an isolated or "dead-end" host for influenza A viruses, with equine influenza virus being considered as relatively stable genetically. Although equine influenza viruses are genetically more stable than those of human lineage, they are by no means in evolutionary stasis. Moreover, recent transmission of equine-lineage influenza viruses to dogs also challenges the horse's status as a dead-end host. This article reviews recent developments in the epidemiology and evolution of equine influenza virus. In addition, the clinical presentation of equine influenz...
García-Bocanegra I, Belkhiria J, Napp S, Cano-Terriza D, Jiménez-Ruiz S, Martínez-López B.During the last decade, West Nile virus (WNV) outbreaks have increased sharply in both horses and human in Europe. The aims of this study were to evaluate characteristics and spatio-temporal distribution of WNV outbreaks in horses in Spain between 2010 and 2016 in order to identify the environmental variables most associated with WNV occurrence and to generate high-resolution WNV suitability maps to inform risk-based surveillance strategies in this country. Between August 2010 and November 2016, a total of 403 WNV suspected cases were investigated, of which, 177 (43.9%) were laboratory confirm...
Badenhorst M, de Heus P, Auer A, Tegtmeyer B, Stang A, Dimmel K, Tichy A, Kubacki J, Bachofen C, Steinmann E, Cavalleri JMV.Equine parvovirus-hepatitis (EqPV-H) research is in its infancy. Information regarding prevalence, geographical distribution, genetic diversity, pathogenesis and risk factors enhances understanding of this potentially fatal infection. Objective: Determining the prevalence of EqPV-H in Austrian equids. Investigating factors increasing probability of infection, liver-associated biochemistry parameters, concurrent equine hepacivirus (EqHV) infection and phylogenetic analysis of Austrian EqPV-H variants. Methods: Cross-sectional study. Methods: Sera from 259 horses and 13 donkeys in Austria were a...
van Maanen C, Sloet van Oldruitenborgh-Oosterbaan MM, Damen EA, Derksen AG.An outbreak of neurological disease caused by EHV-1 infection is described with emphasis on diagnosis and prognosis for recumbent horses. In April 1995, an outbreak of the neurological form of Equine herpesvirus type 1 (EHV-1) occurred in a well-managed riding school with 41 horses: 34 horses showed a temperature spike and 20 some degree of neurological signs, of which 10 were nursed intensively in the indoor arena of the riding school for 3 to 20 days, 8 having to be maintained in slings for 2-18 days, while 9 needed bladder catheterisation b.i.d. for 2-16 days. Within the first 3 days, one h...
Proudman CJ, Edwards GB.A centrifugation/flotation technique for the identification of equine tapeworm eggs is described. It was validated by using faeces samples from 80 horses of known tapeworm status, and had a sensitivity of 61 per cent and a specificity of 98 per cent. The exclusion of false negative results in animals with less than 20 tapeworms increased the sensitivity to 92 per cent. No significant correlation was found between the number of eggs observed and the number of tapeworms present in the horses.
Tenter AM, Friedhoff KT.The sensitivity and specificity of the complement fixation (CF) test for the diagnosis of Babesia infections in equines was assessed, using the indirect fluorescent antibody (IFA) test as a reference. Antibodies were first detected between 11 and 20 days post infection (dpi) in the CF test and between 7 and 14 dpi in the IFA test in ponies infected experimentally with B. equi (USDA strain). The CF test became negative in four of five ponies 63-174 dpi although B. equi was demonstrated microscopically in two of these four ponies up to 364 and 455 dpi. The IFA test remained positive up to 476 dp...
Kasel JA, Couch RB.The recognition of an antigenic relationship between the haemagglutinins of A/Equi-2 and A2/Hong Kong/68 viruses led to experimental studies in man and horses with these virus types.Human volunteers were inoculated with A/Equi-2/Miami/63 virus and virus shedding ensued in all subjects. The most common clinical response was a febrile illness indistinguishable from naturally occurring human influenza. After administration of A2/Hong Kong/68 virus to 10 ponies there was virus shedding from 9 and a febrile response in 6.When the human subjects previously inoculated with equine virus were challenge...
Ghosh M, Sharma N, Singh AK, Gera M, Pulicherla KK, Jeong DK.For more than a quarter of a century, sequencing technologies from Sanger's method to next-generation high-throughput techniques have provided fascinating opportunities in the life sciences. The continuing upward trajectory of sequencing technologies will improve livestock research and expedite the development of various new genomic and technological studies with farm animals. The use of high-throughput technologies in livestock research has increased interest in metagenomics, epigenetics, genome-wide association studies, and identification of single nucleotide polymorphisms and copy number va...
Zhang J.Prion diseases (e.g. Creutzfeldt-Jakob disease (CJD), variant CJD (vCJD), Gerstmann-Straussler-Scheinker syndrome (GSS), Fatal Familial Insomnia (FFI) and Kuru in humans, scrapie in sheep, bovine spongiform encephalopathy (BSE or 'mad-cow' disease) and chronic wasting disease (CWD) in cattles) are invariably fatal and highly infectious neurodegenerative diseases affecting humans and animals. However, by now there have not been some effective therapeutic approaches or medications to treat all these prion diseases. Rabbits, dogs, and horses are the only mammalian species reported to be resistant...
