Infections in horses encompass a range of diseases caused by various pathogens, including bacteria, viruses, fungi, and parasites. These infections can affect different systems within the horse, such as the respiratory, gastrointestinal, and integumentary systems, leading to a variety of clinical signs depending on the pathogen and the severity of the infection. Common infectious diseases in horses include equine influenza, strangles, and equine herpesvirus. Diagnosis often involves clinical examination, laboratory testing, and sometimes imaging, to identify the causative agent and assess the extent of the disease. Treatment strategies may include antimicrobial therapy, supportive care, and preventive measures such as vaccination and biosecurity practices. This page aggregates peer-reviewed research studies and scholarly articles that explore the pathogenesis, diagnosis, treatment, and prevention of infectious diseases in equine populations.
Wickstead FA, Milner PI, Bardell DA.Wound infusion catheters (WICs) have been used in humans and some veterinary species for post-operative local anesthetic administration following a variety of surgical procedures, aiming to reduce post-operative analgesia requirements and improve patient comfort. Benefit in reduction in pain, post-operative analgesia requirements and length of hospital stay are well documented in humans, but use of WICs may not have been widely adopted in veterinary species due to the concern of increased complications, such as dehiscence or surgical site infection (SSI), creating a barrier to their use. This ...
Ramadan RM, Taha NM, Auda HM, Elsamman EM, El-Bahy MM, Salem MA.Equine piroplasmosis is not fully understood regarding pathogenicity, prophylaxis, host immune response expression, and specific vectors. Accurately identifying the parasite vector is crucial for developing an effective control plan for a particular infection. This study focused on morphologically identifying two Hyalomma species (H. anatolicum and H. marginatum) and one Rhipicephalus annulatus (R. annulatus) at the species level. The identification process was followed by phylogenetic analysis using the neighbor-joining method based on the cytochrome oxidase subunit 1 (COXI) gene as a specifi...
Pusterla N, Lawton K, Barnum S.In populations of healthy show horses, the subclinical transmission and circulation of respiratory pathogens can lead to disease outbreaks. Due to recent outbreaks of equine herpesvirus-1 myeloencephalopathy (EHM) in the USA and Europe, many show organizers have instituted various biosecurity protocols such as individual horse testing, monitoring for early clinical disease and increasing hygiene and cleanliness protocols. The aim of this study was to determine the accuracy of detecting EHV-1 in the various environmental samples collected from the stalls of subclinical shedders. Four healthy ad...
Ryt-Hansen P, Johansen VK, Cuicani MM, Larsen LE, Hansen S.Equine herpesvirus 4 (EHV-4) causes respiratory disease in horses, and the virus is considered endemic in the global equine population. However, outbreaks can occur when several horses are gathered in relation to shows, competitions, breeding units and at hospitals. In the spring year 2022, an EHV-4 outbreak occurred at the Large Animal Teaching Hospital, University of Copenhagen, Denmark. Nine horses were tested EHV-4 positive during the outbreak, which lasted approx. seven weeks. In addition, a tenth horse "Eq10" tested EHV-4 positive almost three weeks after the last of the outbreak horses ...
Hu Y, Wu G, Jia Q, Zhang B, Sun W, Sa R, Zhang S, Cai W, Jarhen , Ran D, Liu J.Equid alphaherpesvirus 1 (EqAHV1) is a viral pathogen known to cause respiratory disease, neurologic syndromes, and abortion storms in horses. Currently, there are no vaccines that provide complete protection against EqAHV1. Marker vaccines and the differentiation of infected and vaccinated animals (DIVA) strategy are effective for preventing and controlling outbreaks but have not been used for the prevention of EqAHV1 infection. Glycoprotein 2 (gp2), located on the envelope of viruses (EqAHV1), exhibits high antigenicity and functions as a molecular marker for DIVA. In this study, a series of...
Toner S, Leguillette R, Israel J, Legge C, Samani ARE, Kavanagh M, Goodmanson M.A 21-year-old retired polo Argentinian thoroughbred horse from a teaching herd was presented for a routine bronchoalveolar lavage demonstration, during which an incidental finding of a granulomatous mass on the dorsal aspect of the epiglottis was made. Rhinosporidium seeberi was suspected from a histological section obtained from an initial biopsy, and the mass was removed via laser surgery for cytology and PCR. Sequencing of the PCR amplicons confirmed the diagnosis of R. seeberi. A treatment protocol of nebulized voriconazole for 10 d postoperatively was used. Long-term follow-up required 2 ...
Koziy RV, Bracamonte JL, Katselis GS, Udenze D, Hayat S, Hammond SA, Simko E.Septic arthritis (SA) in horses has long-term health implications. The success of its resolution hinges on the implementation of early, aggressive treatment, which is often sustained over a prolonged period. Common diagnostic methods do not allow for the reliable detection of the eradication of joint infection. A potential alternative is the discovery and characterization of mRNA biomarkers. The purpose of this study was to identify potential mRNA biomarkers for the eradication of joint infection in equine SA and to compare their expression with our previously published proteomics data. In add...
Khan Y, El-Shalofy A, Kaps M, Gautier C, Aurich C.We aimed to determine associations between experimentally impaired uterine clearance or treatment with ecbolic drugs on luteal development in estrous mares after insemination. In a crossover design, eight mares were treated with saline (CON), clenbuterol (CLEN), oxytocin (OXY) and carbetocin (CARB) from the day of first insemination until 2 days after ovulation. Between treatments, the mares rested for one cycle. Estrous mares were examined for the presence of free intrauterine fluid by transrectal ultrasound. Endometrial swabs for cytology and bacteriology were collected on days 1 and 14. Blo...
Sedgwick RL, ElBohy O, Daly JM.In this review, we explore how pseudotyped viruses (PVs) are being applied to the study of viruses affecting both humans and horses. For the purposes of this review, we define PVs as non-replicative viruses with the core of one virus and the surface protein(s) of another and encapsulating a reporter gene such as luciferase. These 'reporter' PVs enable receptor-mediated entry into host cells to be quantified, and thus can be applied to study the initial stages of viral replication. They can also be used to test antiviral activity of compounds and measure envelope protein-specific antibodies in ...
Lovett AL, Riley CB, Chapman V, Bell B, Bishop B, Grierson A, Johnstone LJ, Sykes BW.Horses are exquisitely sensitive to tetanus neurotoxin and are exposed to the risk of infection with throughout life. The vaccine against tetanus is highly effective at preventing disease, whereas tetanus in unvaccinated populations is associated with high mortality rates. Current guidelines in New Zealand and Australia for the available vaccine contain contradictions and limitations surrounding the optimal tetanus immunisation protocols for both adult horses and foals. This review critically evaluates the scientific literature on tetanus prophylaxis in horses within the context of equine pra...
Atabek B, Zhyldyz A, Aitakin K, Rysbek N, Jailobek O, Ahedor B, Mumbi NNM, Ma Y, Otgonsuren D, Perera WPPSI, Guswanto A, Sivakumar T, Yokoyama N.Equine piroplasmosis is caused by Theileria equi and Babesia caballi, which are hemoprotozoan parasites. Understanding the epidemiology and genotypes of T. equi and B. caballi is crucial for developing effective control strategies in endemic countries. However, the endemic status of these two parasite species remains uncertain in Kyrgyzstan due to lack of surveys. Our study, therefore, aimed to detect T. equi and B. caballi infections in Kyrgyzstan and identify their genotypes. Blood samples were collected from 226 horses across all seven provinces of Kyrgyzstan, namely Chuy, Issyk-Kul, Naryn,...
Öhrmalm J, Cholleti H, Theelke AK, Berg M, Gröndahl G.Equid alphaherpesvirus 1 (EHV-1) is a ubiquitous and significant viral pathogen in horses worldwide, causing a range of conditions, including fever, respiratory disease, abortion in pregnant mares and the severe neurological disease called equine herpes myeloencephalopathy (EHM). Despite that EHV-1 is a notifiable animal disease in Sweden, there is limited knowledge about the circulating strains. This study aimed to analyze the genetic diversity of EHV-1 strains in equine samples from different Swedish outbreaks by partial genome sequencing. Genotyping based on three selected open reading fram...
Grabatin M, Fux R, Zablotski Y, Goehring LS, Witte TS.Contagious equine metritis (CEM) is caused by Taylorella equigenitalis. It is a venereal disease that is detected in some breeds more than others and can cause temporary infertility with substantial costs for regular testing, sanitation and retesting. There was a perceived increase in T. equigenitalis-positive cases in Icelandic intact males where natural cover is common. Objective: We aimed to investigate the prevalence of T. equigenitalis in Icelandic intact males and compare to draught horse and Haflinger intact males. We hypothesised that prevalence of T. equigenitalis is higher in Iceland...
Lale D, Dirks EE, Preining I, Lyrakis M, Gömer A, Steinmann E, Cavalleri JV, Ramsauer AS.Equine parvovirus hepatitis (EqPV-H) can cause Theiler's disease and subclinical hepatitis in horses. Objective: Assess the frequency of subclinical EqPV-H infection in hospitalized horses and to study viral transmission by investigating potential shedding routes. Methods: One hundred sixteen equids, that presented to the University Equine Hospital of the University of Veterinary Medicine Vienna between February 2021 and March 2022, for causes other than hepatopathy. Methods: In this cross-sectional study, samples (serum, feces, nasal, and buccal swabs) of hospitalized horses were collected. S...
Afify AF, Hassanien RT, El Naggar RF, Rohaim MA, Munir M.Equid herpesviruses (EHVs) are a group of highly impactful viral pathogens that affect horses, presenting a substantial risk to the global equine industry. Among these, equid herpesvirus-1 (EHV-1) primarily causes respiratory infections. However, its ability to spread to distant organs can lead to severe consequences such as abortion and neurological diseases. These viruses can enter a dormant phase, with minimal activity, and later reactivate to trigger active infections at any time. Recently, there has been a notable rise in the prevalence of a particularly devastating strains of EHV-1 known...
Da Silva E, Martín-Cano FE, Gómez-Arrones V, Gaitskell-Phillips G, Alonso JM, Rey J, Becerro L, Gil MC, Peña FJ, Ortega-Ferrusola C.Equine endometritis is one of the main causes of subfertility in the mare. Unraveling the molecular mechanisms involved in this condition and pinpointing proteins with biomarker potential could be crucial in both diagnosing and treating this condition. This study aimed to identify the endometritis-induced changes in the endometrial proteome in mares and to elucidate potential biological processes in which these proteins may be involved. Secondly, biomarkers related to bacterial endometritis (BE) in mares were identified. Uterine lavage fluid samples were collected from 28 mares (14 healthy: ne...
Bogdan AM, Mitrea IL, Ionita M.Equine granulocytic anaplasmosis (EGA) is a tick-borne disease affecting horses worldwide, caused by . The disease ranges from non-specific clinical signs to fatal outcomes. This paper aimed to analyze EGA cases reported in peer-reviewed journals, particularly on clinico-pathological findings, diagnosis, and therapeutic management. Overall, 189 clinical cases from 31 publications were included in the study. Extensive symptomatology for the EGA cases was reported, of which mostly was fever (90.30%), followed by limb edema (48.51%), anorexia (41.79%), depression (32.84%), icterus (22.39%), ataxi...
de Souza TC, Burford J, Busschers E, Freeman S, Suthers JM.To report the long-term survival of adult horses that were subjected to synovial lavage for treatment of contaminated and septic synovial structures. Methods: Multicenter, prospective observational trial. Methods: Horses (n = 240) presented for synovial sepsis at 10 UK referral centers. Methods: Data for horses presented for treatment of synovial sepsis were collected over a 15 month recruitment period. Owners were contacted a minimum of 365 days after surgery using a structured client interview to assess long term survival. Descriptive statistics, and univariable and Cox proportional haza...
Gandini M, Cerullo A, Giusto G.Surgical site infection (SSI) is a common complication after celiotomy in horses, leading to increased morbidity and costs. Increased concern about antibiotic resistance justifies evaluation of alternative preventive approaches, such a Manuka honey which has displayed antimicrobial properties. Pectin-Honey Hydrogels (PHH), composed by Manuka honey and pectin provide a moist wound environment and microbial growth inhibition. The aim of the study was to evaluate the effectiveness of PHHs in preventing SSI in horses subjected to emergency laparotomy. Horses undergoing laparotomy were evaluated. H...
Williams RAJ, Criollo Valencia HA, López Márquez I, González González F, Llorente F, Jiménez-Clavero MÁ, Busquets N, Mateo Barrientos M....West Nile virus (WNV) is a re-emerging flavivirus, primarily circulating among avian hosts and mosquito vectors, causing periodic outbreaks in humans and horses, often leading to neuroinvasive disease and mortality. Spain has reported several outbreaks, most notably in 2020 with seventy-seven human cases and eight fatalities. WNV has been serologically detected in horses in the Community of Madrid, but to our knowledge, it has never been reported from wild birds in this region. To estimate the seroprevalence of WNV in wild birds and horses in the Community of Madrid, 159 wild birds at a wildli...
Collins EN, Barr EM, Westermeyer H, Gilger BC, Oh A.To determine the predictive value of corneal ultrasound biomicroscopy (UBM) findings for the outcome of equine corneal disease. Methods: 46 horses with a clinical diagnosis of either infectious ulcerative keratitis or stromal abscess. Methods: Corneal UBM (VevoMD; UHF70; VisualSonics) of horses with infectious corneal disease presenting to the North Carolina State University Equine Ophthalmology Service from 2019 to 2023 were evaluated. Size and depth of lesion, presence of Descemet membrane disruption (DMD), corneal thickness, and aqueous humor cell counts (AHCC) were assessed. Comparisons of...
Getahun YA, Tsalke BS, Buzuneh AW, Mejo MM, Habtewold WT.Equines are indispensable in reducing the huge burden on children and women and income generation. On the other hand, minimal attention is given to improving their health and welfare. Objective: This study examined the prevalence and associated risk factors of helminth parasites of equine in the Gamo Gofa Zone. Methods: A cross-sectional study was employed from June 2019 to March 2020. The study districts and were selected purposively based on agroecology whereas selection of study households and animals were performed based on simple random sampling techniques. Identification of nematode, tr...
Li L, Cui X, Yu Y, Sun Q, Li W, Li Y, Li S, Chen L, Khan MZ, Wang C, Wang T.Equid herpesvirus type 8 (EqHV-8) poses a significant threat to equine health, leading to miscarriages and respiratory diseases in horses and donkeys, and results in substantial economic losses in the donkey industry. Currently, there are no effective drugs or vaccines available for EqHV-8 infection control. Unassigned: In this study, we investigated the and antiviral efficacy of Blebbistatin, a myosin II ATPase inhibitor, against EqHV-8. Unassigned: Our results demonstrated that Blebbistatin significantly inhibited EqHV-8 infection in Rabbit kidney (RK-13) and Madin-Darby Bovine Kidney (MDB...
Easton-Jones CA.Primary immune mediated hemolytic anemia (IMHA) and thrombocytopenia (IMTP) are rare in horses with the conditions more commonly occurring secondary to underlying disease. Several case reports have suggested a link between neoplasia and immune-mediated destruction of platelets and red blood cells. Diagnostic investigations should therefore focus on identifying possible underlying causes such as infections and neoplasia. Immunosuppressive therapy with corticosteroids and azathioprine is the mainstay of treatment but should be used cautiously in cases where underlying infection has not been excl...
Munday JS, Knight CG, Bodaan CJ, Codaccioni C, Hardcastle MR.Penile squamous cell carcinomas (SCCs) are common, potentially life-threatening neoplasms of horses. They are well-recognized to be caused by Equus caballus papillomavirus (EcPV) type 2, although EcPV2 cannot be detected in all cases. A 23-year-old standardbred gelding developed multiple penile in situ and invasive SCCs that contained histological evidence of PV infection. By using both consensus and specific PCR primers, these lesions were found to contain EcPV7 DNA, but not DNA from EcPV2 or any other PV type. To determine how frequently EcPV7 is present in equine penile SCCs, specific prime...
Pandit PS, Smith WA, Finno CJ, Aleman M, Conrad PA, Packham A, Plancarte M, Woolard K, Marsh A, Pusterla N.Equine protozoal myeloencephalitis (EPM) is a challenging disease to diagnose in horses with neurological signs. To optimize contemporary diagnostic testing, including the use of serum:CSF antibody ratios, the SarcoFluor antibody test for Sarcocystis neurona requires revalidation. The SarcoFluor, a previously validated immunofluorescent antibody test (IFAT) for the detection of antibodies specific to S. neurona in serum and cerebrospinal fluid (CSF) of naturally infected horses was analyzed using recent data and considering a serum:CSF antibody ratio threshold. Utilization of serum and CSF pho...
Martínez-Boví R, Gaber JTH, Sala-Ayala L, Plaza-Dávila M, Cuervo-Arango J.The effect of embryo reinsertion immediately after embryo flushing was studied. In Experiment 1, eight mares were used during 32 cycles (8 cycles in each group). For the first two groups, inseminated mares were flushed 8 days after ovulation and prostaglandin F2α was not administered: in group EF-ET (embryo flushing and embryo transfer) the embryo was reinserted in the same donor mare, while in the EF group, no further procedure was performed. In the third group (ET), non-inseminated mares (recipients) received a Day 8 embryo. Progesterone concentration was measured before EF/ET and 72 h afte...
Fortier C, El-Hage C, Normand C, Hue ES, Sutton G, Marcillaud-Pitel C, Jeffers K, Bamford N, Oden E, Paillot R, Hartley C, Gilkerson J, Pronost S.Reports of newly discovered equine hepatotropic flavi- and parvoviruses have emerged throughout the last decade in many countries, the discovery of which has stimulated a great deal of interest and clinical research. Although commonly detected in horses without signs of disease, equine parvovirus hepatitis (EqPV-H) and equine hepacivirus (EqHV) have been associated with liver disease, including following the administration of contaminated anti-toxin. Our aim was to determine whether EqPV-H and EqHV are present in Australian horses and whether EqPV-H was present in French horses and to examine ...
Pitchers KG, Boakye OD, Campeotto I, Daly JM.African horse sickness is a devastating viral disease of equids. It is transmitted by biting midges of the genus with mortalities reaching over 90% in naïve horses. It is endemic to sub-Saharan Africa and is seasonally endemic in many parts of southern Africa. However, outbreaks in Europe and Asia have occurred that caused significant economic issues. There are attenuated vaccines available for control of the virus but concerns regarding the safety and efficacy means that alternatives are sought. One promising alternative is the use of virus-like particles in vaccine preparations, which have...
Brandt S, Haralambus R, Schoster A, Kirnbauer R, Stanek C.Bovine papillomaviruses of types 1 and 2 (BPV-1 and -2) chiefly contribute to equine sarcoid pathogenesis. However, the mode of virus transmission and the presence of latent infections are largely unknown. This study established a PCR protocol allowing detection of <or=10 copies of the BPV-1/-2 genes E5 and L1. Subsequent screening of peripheral blood mononuclear cell (PBMC) DNA derived from horses with and without BPV-1/2-induced skin lesions demonstrated the exclusive presence of E5, but not L1, in PBMCs of BPV-1/2-infected equines. To validate this result, a blind PCR was performed from ...
Allen GP, Bolin DC, Bryant U, Carter CN, Giles RC, Harrison LR, Hong CB, Jackson CB, Poonacha K, Wharton R, Williams NM.An emerging problem of equine herpesvirus-1 (EHV-1) infection in horses in the USA is a high-mortality myeloencephalopathy that commonly occurs where large numbers of horses are stabled. EHV-1 isolates recovered from recent neurological outbreaks represent a mutant virus strain that possesses enhanced neuropathogenicity. A central question of EHV-1 myeloencephalopathy is the latency carriage rate for these mutants of EHV-1 in USA horse populations. Objective: To estimate the prevalence of neuropathogenic strains of EHV-1 as latent infections in the Thoroughbred broodmare population of central ...
Faber NA, Crawford M, LeFebvre RB, Buyukmihci NC, Madigan JE, Willits NH.Leptospiral organisms have long been presumed to be associated with the presence of equine recurrent uveitis. This project was undertaken to determine the presence of Leptospira spp. in the aqueous humor of horses with uveitis to determine if there was an association with inflammation. Thirty horses were determined to have recurrent uveitis based on clinical evaluation or history. Sixteen horses were judged clinically and historically to be free of uveitis and were used as controls. Aqueous humor samples were cultured and evaluated by PCR for the presence of Leptospira DNA. Serum was collected...
Middleton D.Hendra virus infection of horses occurred sporadically between 1994 and 2010 as a result of spill-over from the viral reservoir in Australian mainland flying-foxes, and occasional onward transmission to people also followed from exposure to affected horses. An unprecedented number of outbreaks were recorded in 2011 leading to heightened community concern. Release of an inactivated subunit vaccine for horses against Hendra virus represents the first commercially available product that is focused on mitigating the impact of a Biosafety Level 4 pathogen. Through preventing the development of acut...
Soares IR, Silva SO, Moreira FM, Prado LG, Fantini P, Maranhão Rde P, da Silva Filho JM, Melo MN, Palhares MS.This study reports the first evidence of infection by Leishmania infantum in Equus caballus in Americas and the first mixed infection of L. infantum/Leishmania braziliensis on this mammalian species in the world. The diagnoses was based on presence of parasites in lesions and bone marrow aspirates, their identification by using specific primers for L. infantum and L. braziliensis complexes and also serological methods IFAT and ELISA. The analysis of the PCR products suggested mixed infection in three animals. Further studies involving equine leishmaniasis are carrying out in order to clarify t...
Nielsen MK, Haaning N, Olsen SN.Knowledge of horses that shed the same number of strongyle eggs over time can lead to the optimization of parasite control strategies. This study evaluated shedding of strongyle eggs in 424 horses on 10 farms when a selective anthelmintic treatment regime was used over a 3-year period. Faecal egg counts were performed twice yearly, and horses exceeding 200 eggs per gram (EPG) of faeces were treated. The results are presented as probabilities of the egg count outcome, when two previous egg counts are known. A horse with no strongyle eggs detected in the two previous faecal examinations had an 8...
Songer JG, Beckenbach K, Marshall MM, Olson GB, Kelley L.Isolates (n = 94) of Corynebacterium pseudotuberculosis were obtained from sheep, goats, horses, and cattle from various parts of the world. The isolates were characterized biochemically and by restriction endonuclease analysis of DNA. We found near homogeneity in the ability of isolates to ferment carbohydrates and to produce urease. All isolates produced phospholipase D and catalase. The ability of isolates from horses to reduce nitrate, the inability of isolates from sheep and goats to do so, and the correlation of this characteristic with results of restriction endonuclease analyses confir...
Kamada M, Ando Y, Fukunaga Y, Kumanomido T, Imagawa H, Wada R, Akiyama Y.A primary enzootic of equine Getah virus infection involving 722 of 1,903 racehorses occurred at a training center in Japan between September and November of 1978. Sixty-two viral agents were isolated from the plasma of 209 sick horses which exhibited pyrexia with rectal temperatures ranging from 38.5--40 degrees C, urticarial rash on various portions of the body, and edema of the hind legs. The viruses were antigenically related to the AMM 2021, Haruna, and Sagiyama strains of Getah virus. Infection and disease were produced experimentally in horses when inoculated by the intramuscular or int...
Fingerhut L, Ohnesorge B, von Borstel M, Schumski A, Strutzberg-Minder K, Mörgelin M, Deeg CA, Haagsman HP, Beineke A, von Köckritz-Blickwede M....Equine recurrent uveitis (ERU) is considered one of the most important eye diseases in horses and typically appears with relapsing inflammatory episodes without systemic effects. Various disorders have been described as an initial trigger, including infections. Independent of the initiating cause, there are numerous indications that ERU is an immune-mediated disease. We investigated whether neutrophil extracellular traps (NETs) are part of the ERU pathogenesis. Therefore, vitreous body fluids (VBF), sera, and histological sections of the eye from ERU-diseased horses were analyzed for the prese...
Woolcock JB, Farmer AM, Mutimer MD.The development of a selective medium for the isolation of Corynebacterium equi is described. The medium has been used to examine fecal samples from 127 horses of which 90 have been found to carry the organism.
Li F, Craigo JK, Howe L, Steckbeck JD, Cook S, Issel C, Montelaro RC.Previous evaluations of inactivated whole-virus and envelope subunit vaccines to equine infectious anemia virus (EIAV) have revealed a broad spectrum of efficacy ranging from highly type-specific protection to severe enhancement of viral replication and disease in experimentally immunized equids. Among experimental animal lentivirus vaccines, immunizations with live attenuated viral strains have proven most effective, but the vaccine efficacy has been shown to be highly dependent on the nature and severity of the vaccine virus attenuation. We describe here for the first time the characterizati...
Rwambo PM, Issel CJ, Adams WV, Hussain KA, Miller M, Montelaro RC.Three ponies were inoculated with plasma containing 10(4.8) TCID50 of equine infectious anemia virus (EIAV) and observed for 165 to 440 days. Each pony developed a febrile response within 3 weeks of infection during which a plasma viremia greater than or equal to 10(3.5) TCID50/ml was observed. Analyses of four isolates from sequential febrile episodes in a single pony were conducted by two-dimensional tryptic peptide maps and with monoclonal antibodies in immunoblots. Structural and antigenic alterations were observed in the envelope glycoproteins gp90 and gp45, with greatest variation in gp9...
Short MA, Clark CK, Harvey JW, Wenzlow N, Hawkins IK, Allred DR, Knowles DP, Corn JL, Grause JF, Hennager SG, Kitchen DL, Traub-Dargatz JL.A 7-year-old Quarter Horse gelding was hospitalized in Ocala, Fla, because of lethargy, fever, anorexia, and swelling of distal aspects of the limbs. A tentative diagnosis of equine piroplasmosis (EP) was made on the basis of examination of a blood smear. The case was reported to the Florida State Veterinarian, and infection with Babesia equi was confirmed. The subsequent investigation included quarantine and testing of potentially exposed horses for B equi and Babesia caballi infections, tick surveillance, and owner-agent interviews. Results: 210 horses on 25 premises were tested for infectio...
Wada R, Kamada M, Anzai T, Nakanishi A, Kanemaru T, Takai S, Tsubaki S.Twelve foals, between 27 and 83 days old, were infected with 2 strains of Rhodococcus equi by intratracheal administration. Ten of the 12 foals were inoculated with 10(4)-10(10) colony forming units (cfu) of ATCC 33701 strain. The other 2 foals were inoculated with 10(9) cfu of a plasmid-cured derivative of the ATCC 33701 strain (ATCC 33701P-). All of the 10 foals challenged with the ATCC 33701 strain showed clinical signs of pulmonary disease within 5-13 days, such as gross lesions associated with acute bronchopneumonia and microscopic lesions associated with granulomatous pneumonia. The two ...
Taniguchi K, Urasawa T, Urasawa S.We determined the nucleotide and deduced amino acid sequences of the VP4 genes of five equine, two feline, and two canine rotavirus strains. A high degree of homology (> 97.0%) was found among the VP4 amino acid sequences of the equine strains H2, FI-14, and FI23. Equine strain L338 has a distinct VP4 amino acid sequence from those of the other equine strains (78.1% or less homology), and the L338 VP4 exhibited more than 17.0% divergence at the amino acid level from those of rotavirus strains published so far. The VP4 amino acid sequence of equine strain H1, which showed low homology with t...
Issel CJ, Adams WV, Meek L, Ochoa R.Twenty seven adult horses positive to the agar gel immunodiffusion (AGID) test for equine infectious anemia (EIA), but with no history of clinical EIA, were used in transfusion studies to determine whether infectious EIA virus was present in 1 to 5 ml of their blood. Of 27 recipients, 21 (78%) became AGID test-positive at an average of 24 days after inoculation. Two horses that were initially negative when screened were retested and found to carry infectious virus in 5-300 ml of whole blood; the other 4 horses were not retested. Horse flies (Tabanus fuscicostatus Hine) were unable to transmit ...
Milinovich GJ, Klieve AV, Pollitt CC, Trott DJ.Equine laminitis is the most serious foot disease of the horse, often resulting in death or euthanasia. Laminitis has long been recognized as an affliction of horses, as has the association of this condition with the ingestion of carbohydrates. Research into the pathophysiology of this condition has been facilitated by the development of reliable models for experimentally inducing laminitis, and DNA-based techniques for profiling complex microbiomes have dramatically increased the knowledge of the microbiology of this disease. Recent studies have provided substantial evidence showing equine hi...
Gieling F, Peters S, Erichsen C, Richards RG, Zeiter S, Moriarty TF.Bacterial osteomyelitis in veterinary patients can be challenging to diagnose and treat, given limited therapeutic options and reported success rates. Osteomyelitis is frequently associated with surgical implant devices, including those required to optimise stability and healing of fractures. However, management of osteomyelitis sometimes necessitates the removal of these surgical implant devices in order to eradicate infection or limit implant-related osteolysis. The goal of this article is to provide a general and species-specific review of bacterial osteomyelitis in a selection of domestic ...
Engvall EO, Pettersson B, Persson M, Artursson K, Johansson KE.A PCR-based assay was developed for detecting DNA of granulocytic ehrlichiae in blood samples from dogs, horses, and cattle, Primers were designed from 16S rRNA sequence information to specifically amplify DNA from a newly identified Swedish Ehrlichia species. The 16S rRNA nucleotide sequence of this Swedish species differs in only two and three positions from the sequences of Ehrlichia phagocytophila and Ehrlichia equi, respectively, which were also amplified by this PCR system. For evaluation, PCR results were compared with microscopic examination of stained blood smears for the detection of...
Clark C, Greenwood S, Boison JO, Chirino-Trejo M, Dowling PM.All bacterial samples of equine origin submitted to the diagnostic laboratory at the Western College of Veterinary Medicine from January 1998 to December 2003 from either "in-clinic" or Field Service cases were accessed (1323 submissions). The most common bacterial isolates from specific presenting signs were identified, along with their in vitro antimicrobial susceptibility patterns. The most common site from which significant bacterial isolates were recovered was the respiratory tract, followed by wounds. Streptococcus zooepidemicus was the most common isolate from most infections, followed ...
Hines SA, Stone DM, Hines MT, Alperin DC, Knowles DP, Norton LK, Hamilton MJ, Davis WC, McGuire TC.Rhodococcus equi is a gram-positive bacterium that infects alveolar macrophages and causes rhodococcal pneumonia in horses and humans. The virulence plasmid of R. equi appears to be required for both pathogenicity in the horse and the induction of protective immunity. An understanding of the mechanisms by which virulent R. equi circumvents protective host responses and by which bacteria are ultimately cleared is important for development of an effective vaccine. Six adult horses were challenged with either virulent R. equi or an avirulent, plasmid-cured derivative. By using a flow cytometric m...
Nordengrahn A, Rusvai M, Merza M, Ekström J, Morein B, Belák S.Equine herpesvirus type 2 (EHV-2), a member of the Gammaherpesvirinae subfamily, was studied in a two-phase respiratory disease complex of young foals as a predisposing factor for the secondary bacterial invasion of lungs with Rhodococcus equi (R. equi). Foals were immunized against EHV-2 on a farm where R. equi pneumonia regularly occurred during the last years. The immunizations were performed by using a subunit vaccine which selectively presents envelope glycoproteins of EHV-2 in a multimeric form of immunostimulating complexes (iscoms). The etiological role of EHV-2 was estimated by observ...
Paillot R, Prowse L, Montesso F, Huang CM, Barnes H, Escala J.Equine influenza (EI) is a serious respiratory disease of horses induced by the equine influenza virus (EIV). Surveillance, quarantine procedures and vaccination are widely used to prevent or to contain the disease. This study aimed to further characterise the immune response induced by a non-updated inactivated EI and tetanus vaccine, including protection against a representative EIV isolate of the Florida clade 2 sublineage. Seven ponies were vaccinated twice with Duvaxyn IE-T Plus at an interval of four weeks. Five ponies remained unvaccinated. All ponies were experimentally infected with t...
Park T, Cheong H, Yoon J, Kim A, Yun Y, Unno T.(1) Background: The intestinal microbiota plays an essential role in maintaining the host's health. Dysbiosis of the equine hindgut microbiota can alter the fermentation patterns and cause metabolic disorders. (2) Methods: This study compared the fecal microbiota composition of horses with intestinal disease and their healthy counterparts living in Korea using 16S rRNA sequencing from fecal samples. A total of 52 fecal samples were collected and divided into three groups: horses with large intestinal disease (n = 20), horses with small intestinal disease (n = 8), and healthy horses (n = 24). (...
Vo AT, van Duijkeren E, Fluit AC, Gaastra W.The aim of the present study was to contribute to the knowledge on extended-spectrum beta-lactamases (ESBL's), AmpC beta-lactamases and integrons in Enterobacteriaceae isolated from horses, which is still limited. The susceptibility of 1581 clinical isolates from animals to ceftiofur was tested. Most of these isolates (n=1347) originated from horses. Seven ceftiofur-resistant equine isolates (four Escherichia coli and three Klebsiella pneumoniae) were identified and all seven were multidrug-resistant. These isolates were further studied for the presence of ESBL's, AmpC beta-lactamases and clas...
Nielsen MK, Wang J, Davis R, Bellaw JL, Lyons ET, Lear TL, Goday C.The equine ascarid parasite Parascaris equorum is well known as a ubiquitous parasite infecting foals. A sibling species, Parascaris univalens, was first described over 130 years ago, but very little attention has been given to its existence and possible implications for anthelmintic resistance, clinical disease, or host age spectrum. P. univalens only possesses one germ line chromosome pair as opposed to two for P. equorum, but the two species are otherwise considered morphologically identical. For the present study, live worms obtained from the University of Kentucky parasitology horse herd ...
