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.
van Zyl A, Daniel J, Wayne J, McCowan C, Malik R, Jelfs P, Lavender CJ, Fyfe JA.Two horses were diagnosed as having Mycobacterium ulcerans infections. The first was a 21-year-old Quarterhorse-cross mare living in Mallacoota (a coastal town near the border of New South Wales and Victoria, Australia) that presented with lichenification, hair-loss and oedema on a fetlock, which subsequently ulcerated, as well as a non-healing ulcer on the wither. The second horse was a 32 year-old Standardbred gelding from Nicholson, near Bairnsdale, Victoria, that had an ulcerated lesion on its caudal thigh. Histologically, there were characteristic changes seen with M. ulcerans infections ...
Fasanella A, Garofolo G, Galante D, Quaranta V, Palazzo L, Lista F, Adone R, Jones MH.Anthrax is a disease of humans and animals caused by the encapsulated, spore-forming Bacillus anthracis. In Italy, anthrax is normally a sporadic disease. During the summer 2004, anthrax broke out in the Basilicata, in southern Italy, a region with a low prevalence of anthrax in which vaccination had been suspended since 1998. The disease involved several animals in few weeks and in a large area. Over 41 days, 81 cattle died, as well as 15 sheep, 9 goats, 11 horses and 8 deer. The Multiple-locus Variable-Number Tandem Repeats Analysis (MLVA) showed that all the 53 isolates belonged to the Clus...
Ousey JC, Palmer L, Cash RS, Grimes KJ, Fletcher AP, Barrelet A, Foote AK, Manning FM, Ricketts SW.Standard bacteriological methods for identifying Taylorella equigenitalis in cervical smears are time consuming. Therefore, a more rapid real-time PCR assay was evaluated for its suitability in screening swabs. Objective: To compare the results of a commercially available real-time PCR assay with routine microbiological culture for the identification of T. equigenitalis, the causative organism of contagious equine metritis, in equine genital swab samples, under 'field trial' conditions. Methods: Routine prebreeding genital swabs (n=2072) collected from Thoroughbred mares and stallions during 2...
Hajialilo E, Ziaali N, Harandi MF, Saraei M, Hajialilo M.In the present study, the prevalence of antibodies to Toxoplasma gondii in sport horses of Qazvin was examined using modified agglutination test (MAT). On 52 horse sera totally examined for anti-Toxoplasma antibodies, 37 horses (71.2%) were seropositive by MAT. Results of the present study showed a high rate of Toxoplasma infection in horses in Qazvin area. More comprehensive study on equine toxoplasmosis is recommended.
Rogers CW, Cogger N.To examine the on-farm biosecurity practices of a group of commercial Thoroughbred stud farms in the North Island of New Zealand, in the absence of an exotic disease outbreak. Methods: A cross-sectional survey of biosecurity practices was conducted during the 2006/2007 Thoroughbred breeding season, and consisted of data from commercial Thoroughbred farms in the North Island of New Zealand standing a stallion. Data were collected on-farm by a single interviewer, using 17 open, closed and multiple-choice questions examining general farm/operation size and features, general animal health and bios...
Abbott Y, Leggett B, Rossney AS, Leonard FC, Markey BK.A retrospective analysis and prospective surveillance study were conducted to determine isolation rates of meticillin-resistant Staphylococcus aureus (MRSA) in dogs, cats and horses in Ireland. Clinical samples that had been submitted to University College Dublin (UCD) for routine microbiological examination over a four-year period (2003 to 2006) were analysed in the retrospective analysis, which included clinical samples from 3866 animals. In the prospective surveillance study, samples from healthy animals presenting for elective surgery as well as from animals with a clinical presentation su...
Pronost S, Léon A, Legrand L, Fortier C, Miszczak F, Freymuth F, Fortier G.Equine herpesvirus 1 (EHV-1) is a common pathogen of the horse which may induce mild respiratory distress, abortion, neonatal death and neurological disease. A single nucleotide polymorphism in the EHV-1 DNA polymerase (ORF30 A(2254) to G(2254)) has been associated with clinical signs of Equine herpes myeloencephalopathy (EHM). The aim of this work was to analyze the ORF30 genomic region among a panel of EHV-1 DNA extract in order to estimate the prevalence of the EHV-1 neuropathogenic genotype in France. Samples coming from cases associated with EHM, horses with respiratory symptoms and abort...
Groppelli E, Tuthill TJ, Rowlands DJ.Equine rhinitis A virus (ERAV) is genetically closely related to foot-and-mouth disease virus (FMDV), and both are now classified within the genus Aphthovirus of the family Picornaviridae. For disease security reasons, FMDV can be handled only in high-containment facilities, but these constraints do not apply to ERAV, making it an attractive alternative for the study of aphthovirus biology. Here, we show, using immunofluorescence, pharmacological agents, and dominant negative inhibitors, that ERAV entry occurs (as for FMDV) via clathrin-mediated endocytosis and acidification of early endosomes...
Araujo JM, Araújo JV, Braga FR, Carvalho RO.Three isolates of predator fungi Duddingtonia flagrans (AC001), Monacrosporium thaumasium (NF34), and Arthrobotrys robusta (I-31) were assessed in in vitro test regarding the capacity of prey infective larvae (L(3)) Strongyloides westeri. Compared to control, without fungus, there was a significant decrease (P 0.01) in vitro test. Linear regression coefficients of treated and control groups were -0.21 for control, -0.32 for D. flagrans, -0.34 for M. thaumasium, and -0.22 for A. robusta. In the following, isolates AC001 and NF34 were assessed in vivo regarding the capacity of supporting the pa...
Medina-Torres CE, Weese JS, Staempfli HR.Clostridium difficile infection (CDI) is a recognized cause of colitis in the horse. Identification of its toxins is important for management of individual cases and for prevention of transmission and zoonosis. In humans, CDI diagnosis is performed with enzyme immunoassays, none of which have been validated for horses. Objective: (1) Establish which test for CDI diagnosis was more frequently used by diagnostic laboratories, (2) determine the identified test's performance, sensitivity, and specificity, and (3) validate its use in diarrheic horses. Methods: Samples were obtained from 72 horses p...
Panchaud Y, Gerber V, Rossano A, Perreten V.Bacterial infections present a major challenge in equine medicine. Therapy should be based on bacteriological diagnosis to successfully minimize the increasing number of infections caused by multidrug-resistant bacteria. The present study is a retrospective analysis of bacteriological results from purulent infections in horses admitted at the University Equine Clinic of Bern from 2004 to 2008. From 378 samples analyzed, 557 isolates were identified, of which Staphylococcus aureus, Streptococcus equi subsp. zooepidemicus and coliforms were the most common. Special attention was paid to infectio...
Brooks BW, Lutze-Wallace CL, Maclean LL, Vinogradov E, Perry MB.Lipopolysaccharides (LPSs) from Taylorella equigenitalis, the causative agent of contagious equine metritis, and T. asinigenitalis were compared by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). Lipopolysaccharide profiles of 11 T. equigenitalis strains were similar, but different from the profiles of 3 T. asinigenitalis strains, and the profiles of 2 T. asinigenitalis strains were similar to each other. The serological specificities of the LPSs from these 14 strains were examined by immunoblotting and enzyme-linked immunosorbent assay with monoclonal antibodies (MAbs) ...
Hagos A, Goddeeris BM, Yilkal K, Alemu T, Fikru R, Yacob HT, Feseha G, Claes F.Trypanocidal sensitivity studies were conducted to assess the efficacy of Diminazene diaceturate (Diminasan) and Bis (aminoethylthio) 4-melaminophenylarsine dihydrochloride (Cymelarsan) against Trypanosoma equiperdum (isolated from two mares with chronic cases of dourine) 713/943 and 834/940 Dodola strains in experimentally infected mice and horses. Diminasan at doses from 3.5 mg/kg to 28 mg/kg and Cymelarsan at doses of 0.25 mg/kg and 0.5 mg/kg body weight failed to cure any of the mice, indicating a clear dose dependent relationship in the mean time of relapse observed in mice. Indeed, mice ...
Kirkland PD, Finlaison DS, Crispe E, Hurt AC.During the 2007 equine influenza outbreak in Australia, respiratory disease in dogs in close contact with infected horses was noted; influenza (H3N8) virus infection was confirmed. Nucleotide sequence of the virus from dogs was identical to that from horses. No evidence of dog-to-dog transmission or virus persistence in dogs was found.
Alvarez I, Gutierrez G, Barrandeguy M, Trono K.The purpose of this study was to develop and evaluate a simple immunochromatographic lateral flow (ICLF) test for specific detection of Equine infectious anemia virus (EIAV) antibodies in equine sera. Viral recombinant p26 capsid protein (rp26) was used as the capture protein in the test line and as the detector reagent conjugated to colloidal gold. The performance of rp26-ICLF was evaluated, and the results obtained were compared with a commercially available agar gel immunodiffusion (AGID) test used as a standard of comparison according to international guidelines. The values obtained for co...
Ackerson LK, Viswanath K.Previous research has found that members of the public have a skewed sense of health risk. The purpose of this research was to investigate how mass media use influences perceptions of threat from cancer and eastern equine encephalitis (EEE). Investigators performed a media content analysis of 253 health-related articles from 11 Massachusetts newspapers, then used logistic regression to analyze responses to a health communication survey of 613 Massachusetts adults. A greater proportion of cancer articles compared to those about EEE mentioned progress in combating the disease (61.0% vs. 16.2%, P...
Turowska A, Pajak B, Godlewski MM, Dzieciatkowski T, Chmielewska A, Tucholska A, Banbura M.Viruses can reorganize the cytoskeleton and restructure the host cell transport machinery. During infection viruses use different cellular cues and signals to enlist the cytoskeleton for their mission. However, each virus specifically affects the cytoskeleton structure. Thus, the aim of our study was to investigate the cytoskeletal changes in homologous equine dermal (ED) and heterologous Vero cell lines infected with either equine herpesvirus 1 (EHV-1) strain Rac-H or Jan-E. We found that Rac-H strain disrupted actin fibers and reduced F-actin level in ED cells, whereas the virus did not infl...
Paillot R, Prowse L, Donald C, Medcalf E, Montesso F, Bryant N, Watson J, Jeggo M, Elton D, Newton R, Trail P, Barnes H.An outbreak of H3N8 Equine Influenza virus (EIV) that occurred in vaccinated horses in Japan was caused by a genetically divergent EIV isolate of the Florida clade 1 sub-lineage. This virus subsequently entered Australia where it infected thousands of immunologically naïve horses. The objective of this study was to evaluate the ability of a non-updated whole inactivated equine influenza (EI) vaccine to protect if used in the face of an outbreak induced by a virus similar to the ones circulating in Japan and Australia in 2007. Seven naïve Welsh mountain ponies were immunised twice with the co...
Quan M, Lourens CW, MacLachlan NJ, Gardner IA, Guthrie AJ.Nucleotide sequences of 52 South African isolates of African horse sickness virus (AHSV) collected during 2004-2005 and including viruses of all nine AHSV serotypes, were used to design and develop a duplex real-time reverse transcription quantitative PCR (RT-PCR) assay targeting the VP7 (S8) and NS2 (S9) genes of AHSV. The assay was optimized for detection of AHSV in fresh and frozen blood of naturally infected horses. Assay performance was enhanced using random hexamers rather than gene-specific primers for RT, and with denaturation of double-stranded RNA in the presence of random hexamers. ...
Harris SP, Fujiwara N, Mealey RH, Alperin DC, Naka T, Goda R, Hines SA.Immune adult horses have CD8(+) cytotoxic T lymphocytes (CTLs) that recognize and lyse Rhodococcus equi-infected cells in an equine lymphocyte alloantigen (ELA)-A [classical major histocompatibility complex (MHC) class I]-unrestricted fashion. As protein antigens are MHC class I-restricted, the lack of restriction suggests that the bacterial antigens being recognized by the host are not proteins. The goals of this study were to test the hypothesis that these CTLs recognize unique R. equi cell-wall lipids related to mycobacterial lipids. Initial experiments showed that treatment of soluble R. e...
Kitai Y, Kondo T, Konishi E.A complement-dependent cytotoxicity (CDC) assay was established to measure antibodies to the West Nile virus (WNV) nonstructural protein 1 (NS1) in horses. Sera collected from a WNV-infected horse mediated lysis of WNV NS1-expressing cells in a dose-dependent manner at higher percentages than sera from a Japanese encephalitis virus (JEV)-infected horse. The percentages of specific lysis for sera diluted 1:10 to 1:80 were <19.8% (assay cutoff) for almost all of the 100 JEV-infected or uninfected horses tested, in contrast to 55 to 76% in WNV-infected horses. Experimental infection revealed t...
Garner MG, Cowled B, East IJ, Moloney BJ, Kung NY.In August 2007, Australia which had previously been free of equine influenza, experienced a large outbreak that lasted approximately 4 months before it was eradicated. The outbreak required a significant national response by government and the horse industries. The main components of the response were movement controls, biosecurity measures, risk-based zoning and, subsequently, vaccination to contain the outbreak. Although not initially used, vaccination became a key element in the eradication program, with approximately 140000 horses vaccinated. Vaccination is recognised as a valuable tool fo...
Malik P, Khurana SK, Dwivedi SK.Glanders, a notifiable highly contagious disease primarily of equids, is a disease of high zoonotic importance. Caused by gram-negative bacillus, Burkholderia mallei, the disease was restricted to certain pockets of India with sporadic cases. Recently, a major outbreak of glanders occurred in India starting from Maharashtra. Following clinical signs and symptoms and laboratory investigations on serum, nasal swab and pus swab samples, it was confirmed as glanders among equines in Pune and Panchgani areas of Maharashtra. One pus sample and three nasal swabs yielded B. mallei isolates while 23 se...
Nishiura H, Satou K.An outbreak of equine influenza (H3N8) occurred among fully vaccinated racehorses in Japan from August to September, 2007. To assess the potential effectiveness of public health interventions other than vaccination (i.e. movement restriction, isolation and quarantine), which started immediately on the date of detection of the first febrile case, a simple epidemiological model was developed and applied to the observed data. The epidemic curves in five racehorse facilities revealed consistent temporal patterns: (i) a sharp increase in symptom onset of cases during the first 3 days, which is thou...
Johnson AL, McAdams SC, Whitlock RH.The objective of the current retrospective study was to describe naturally occurring type A botulism in horses in the United States. In the past 10 years, the Botulism Laboratory at the University of Pennsylvania's School of Veterinary Medicine has identified 3 isolated cases and 8 outbreaks of type A botulism in horses via samples positive for Clostridium botulinum type A toxin or spores using the mouse bioassay test. Additional information was obtained by review of submission forms and by telephone or email interviews. Almost all type A cases and outbreaks occurred in the western United Stat...
Meehan M, Burke FM, Macken S, Owen P.Streptococcus equi possesses a haem-uptake system homologous to that of Streptococcus pyogenes and Streptococcus zooepidemicus. The system consists of two ligand-binding proteins (Shr and Shp) and proteins (HtsA-C) with homology to an ABC transporter. The haem-uptake system of S. equi differs from that of S. pyogenes and S. zooepidemicus in that Shr is truncated by two-thirds. This study focused on the SeShr, SeShp and SeHtsA proteins of S. equi. Analysis of shr, shp and shphtsA knockout mutants showed that all three proteins were expressed in vitro and that expression was upregulated under co...
Pusterla N, Wattanaphansak S, Mapes S, Collier J, Hill J, Difrancesco M, Gebhart C.Equine proliferative enteropathy (EPE) is an emerging disease of weanling foals. Objective: Describe clinical, hematologic, biochemical, serologic, molecular, and ultrasonographic findings in foals experimentally infected with Lawsonia intracellularis. Methods: Eight foals. Methods: Recently weaned foals were assigned to either the challenge (n = 3), the sentinel (n = 3), or the control (n = 2) group. Foals were experimentally challenged via intragastric inoculation of 3 x 10(10)L. intracellularis organisms grown in culture. Each experimentally infected foal was housed with a sentinel foal in ...
Mir IA, Kumar B, Taku A, Faridi F, Bhat MA, Baba NA, Maqbool T.Present study was undertaken to study the prevalence of β-haemolytic streptococci in equine of northern temperate region of Jammu and Kashmir, India. One hundred and forty one samples were collected in duplicate from nasopharyngeal tract of diseased (53) and apparently healthy equine (88) for isolation and direct PCR. A total of 77 isolates of streptococci were recovered from 141 samples with an overall prevalence rate of 54.60%. Out of these 77 isolates, 52 were from diseased and 25 from apparently healthy animals. Of the 77 isolates, 4 were identified as Streptococcus equi subsp. equi, 56 a...
Finger MA, de Barros Filho IR, Leutenegger C, Estrada M, Ullmann LS, Langoni H, Kikuti M, Dornbush PT, Deconto I, Biondo AW.Cart horses are a re-emerging population employed to carry recyclable material in cities. Methods: Sixty-two horses were sampled in an endemic area of human leptospirosis. The microscopic agglutination test (MAT) and real-time polymerase chain reaction (qPCR) were performed. Results: A seropositivity of 75.8% with serovar Icterohaemorrhagiae in 80.8% of the horses was observed. Blood and urine were qPCR negative. MAT showed positive correlations with rainfall (p = 0.02) and flooding (p = 0.03). Conclusions: Although horses may be constantly exposed to Leptospira spp. in the environment mostly ...
Morales GA, Wells EA, Angel D.Discovery of two ill horses and three dogs naturally infected with Trypanosoma evansi near an experimental station in the Eastern Plains of Colombia led to a search for reservoir hosts of the parasite. Infection was detected in 8/33 healthy capybaras (Hydrochoerus hydrochaeris), none of the remaining 14 horses, and none of 32 Zebu cattle (Bos indicus), 18 paca (Cuniculus paca) and 20 spiny rats (Proechimys sp.). Contrary to common opinion, the results indicated a carrier state in the capybara. Diagnosis was based on morphology, behaviour in albino rats, and pathogenicity and host range in dome...
Libardoni F, Vielmo A, Farias L, Matter LB, Pötter L, Spilki FR, de Vargas AC.Strangles is the main upper respiratory tract disease of horses. There are currently no studies on the changes in alleles of the M protein gene (seM) in Brazilian isolates of Streptococcus equi ssp. equi (S. equi). This study aimed to analyze and differentiate molecularly S. equi isolates from equine clinical specimens from southern Brazil, between 1994 and 2010. seM alleles were analyzed in 47 isolates of S. equi obtained from clinical cases of strangles (15 Thoroughbred horses, 29 Crioulo breed horses and three Brasileiro de Hipismo--BH). seM alleles characterization was performed by compari...
Hosseini M, Moraveji M, Tahamtan Y, Rahimian A, Mohammadi G, Namavari M.Neospora caninum, an obligate intracellular protozoan parasite, is recognized as a major cause of abortion in cattle, while limited information is presently available on the seroprevalence of Neospora antibodies in horses' worldwide. The aim of the present study was to determine serologic prevalence of Neospora infection in horses in Iran. Methods: Sera from 150 horses from Mashhad suburb in Razavi Khorasan Province, northeast Iran were examined for antibodies to Neospora spp. using Neospora modified direct agglutination test (N-MAT). Results: Antibodies to this parasite were detected in 45 (3...
Dutta SK.An adenovirus was isolated from a foal with respiratory tract disease. The virus produced cytopathic effects (CPE) in equine embryo kidney (EEK) cell culture, contained deoxyribonucleic acid (DNA), was resistant to chloroform and pH 3, and was moderately resistant to heat. The virus caused hemagglutination of human (type O) erythrocytes. Viral density was 1.34 g/cm,3 and diameter was 75 nm. An adenovirus-associated virus (AAV) isolated from the infected cell culture was 22 nm in diameter. These viruses are classified as equine adenovirus and equine AAV.
Bocklisch H, Ludwig C, Lange S.Between 1982 and 1989 59 equine fetuses were investigated for chlamydiae using animal experiments and embryonated eggs. Chlamydiae were isolated from 16 fetuses (27.1%) originating from 8 studs. The macroscopical lesions of the fetal organs were characterized by extensive haemorrhages. The histological picture shows severe lesions of the blood vessels of different organs. In 6 studs in which chlamydiae had been isolated, blood sera of clinically healthy and pregnant mares were investigated for antibodies during 1989 and 1990. Antibody titres between 1:10++ and 1:40 were detected by using compl...
Burrows R, Denyer M.The antigenic relationships between the haemagglutinins of five A/equine-1 viruses and between six A/equine-2 viruses were examined using post-infection ferret and immunized pony sera. Similar results were obtained with sera from both species for the A/equine-1 viruses and these confirmed minor antigenic differences between the prototype A/Prague 1/56 virus and viruses isolated in England in 1973 and 1977. Considerable antigenic differences were found between five of the A/equine-2 viruses, using ferret sera, but these differences were less evident using pony sera. The response of ponies to th...
Xuan X, Chahan B, Huang X, Yokoyama N, Makala LH, Igarashi I, Fujisaki K, Maruyama S, Sakai T, Mikami T.The prevalence of equine piroplasmosis in Xinjiang province, China, was examined by enzyme-linked immunosorbent assays (ELISAs). A total of 70 serum samples were taken from horses pastured on three farms in western Xinjiang, and examined for diagnosis of equine Babesia equi (B. equi) infection and B. caballi infection by ELISAs using recombinant equi merozoite antigen 1 (EMA-1) and recombinant P48 antigen, respectively. Of the 70 samples, 28 (40.0%) and 17 (24.3%) samples were positive for B. equi infection and B. caballi infection, respectively. In addition, 11 (15.7%) samples were positive f...
Collins MD, Rodriguez Jovita M, Lawson PA, Falsen E, Foster G.Two strains of an unknown Gram-positive, catalase-negative, facultatively anaerobic coccus originating from the reproductive tract of horses were characterized by phenotypic and molecular taxonomic methods. Comparative 16S rRNA gene sequencing studies demonstrated that the two strains constitute a new subline within the lactic-acid group of bacteria, close to, but distinct from, Abiotrophia defectiva, Globicatella sanguinis and close relatives. The unknown bacterium was readily distinguished from other described Gram-positive, catalase-negative cocci by biochemical tests and electrophoretic an...
Mutimer MD, Prescott JF, Woolcock JB.One hundred strains of Rhodococcus equi from various animal species and sources in Australia were examined for capsular serotype. Eighty-four of the strains fell into the existing 7 serotypes, and just under half of the strains belonged to serotype 1. Isolates from the intestines and faeces of horses, cattle, pigs and other species, and from soil, were found to belong to the same serotypes as those recovered from the lungs of foals with R. equi pneumonia. There was no clear relationships between capsular serotype and source of origin of the isolates.
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...
Echeverría MG, Pecoraro MR, Galosi CM, Etcheverrigaray ME, Nosetto EO.This paper describes the first isolation of equine arteritis virus (EAV) in Argentina. The virus was isolated from the semen of an imported seropositive stallion held in isolation at a breeding farm in Tandil in the Buenos Aires Province. In addition, viral nucleic acid was detected in seminal plasma using the reverse-transcription polymerase chain reaction. The isolated virus was propagated in cell cultures and confirmed as EAV by indirect immunofluorescence and virus neutralisation, using a serum specific for the reference Bucyrus strain of EAV. As far as the authors are aware, this is the f...
Vengust M, Staempfli H, Prescott JF.A 10-year-old warmblood gelding was evaluated for intermittent pyrexia, dullness, weight loss, and progressive respiratory disease. Multifocal necrotic pneumonia and pleuritis due to Rhodococcus equi infection was diagnosed. Case management is discussed, as well as factors that may have led to this rare cause of pleuropneumonia in an adult horse.
Larsen AB, Moon HW, Merkal RS.The susceptibility of horses to Mycobacterium paratuberculosis was studied. A total of 8 colts was used: 2 colts were exposed intravenously and 1 colt used as a contact control was placed with them; 2 colts were exposed intragastrically; 1 colt was administered killed M. paratuberculosis intravenously; and the remaining 2 colts were used as normal controls and were housed separately. Colts administered live bacilli intravenously began losing weight 84 days after exposure, and shortly thereafter they had clinical signs of disease, consisting of loss of body weight and rough coat. The exposed co...
Moorthy AR, Spradbrow PB, Eisler ME.Vaginal swabs from 19 mares and penile swabs from 4 stallions were cultured for mycoplasmas. A single semen sample from one of the stallions was also examined. Twelve vaginal swabs and 2 penile swabs yielded mycoplasmas. Ten of the positive vaginal swabs were from mares with vaginitis, or with a history of failure of conception. Two were from apparently healthy mares, but one had been served by an infected stallion. One positive penile swab was from a stallion with ulcerative lesions and the other from a stallion with breeding difficulties. All 14 strains of mycoplasma utilised arginine, and t...
Farah AW, Hegazy NA, Romany MM, Soliman YA, Daoud AM.Twenty-three blood samples were used in this study; five were from five naturally infected horses with Babesia equi (B. equi), while eighteen were from asymptomatic horses with equine babesiasis from different localities in Egypt. All samples were subjected to microscopic examination, indirect fluorescent antibody test (IFA) and polymerase chain reaction (PCR). The carrier animals were microscopically detected in 7 out of 18 samples (38.8%) and in 9 of 18 by using IFA (50%), whereas PCR revealed that 14 samples were positive (78%). Two synthetic oligonucleotide primers, based on the B. equi me...
Pearson EG, Hedstrom OR, Sonn R, Wedam J.A 4-day-old foal died with bloody diarrhea. Using a mouse neutralization test, Clostridium perfringens type C was isolated from intestinal contents, and alpha and beta toxins were identified. About 4 m of the jejunum had severe necrohemorrhagic enteritis. Microscopically, large, rod-shaped, gram-positive bacteria were seen on necrotic intestinal villi by use of Brown and Hopp's stains.
Easton-Jones C.Equid gammaherpesviruses are ubiquitous and widespread in the equine population. Despite their frequent detection, their contribution to immune system modulation and the pathogenesis of several diseases remains unclear. Genetic variability and the combination of equid gammaherpesvirus strains a horse is infected with might be clinically significant. Initial gammaherpesvirus infection occurs in foals peripartum with latency then established in peripheral blood mononuclear cells. A novel EHV-5 study suggests that following inhalation equid gammaherpesviruses might obtain direct access to T and B...
Richter M, Hauser B, Kaps S, Spiess BM.A 5-year-old Holsteiner gelding from Germany was presented 2 months after a whitish discoloration of the left cornea was observed. Cytologic examination revealed intra- and extracellular globular structures, up to 4 micro m in size, consisting of a central spherical deeply basophilic body surrounded by an unstained halo. The structures were morphologically consistent with Histoplasma spp. Infection with Histoplasma organisms is not endemic in Europe. Topical use of fluconazole was successful in eliminating Histoplasma organisms within 10 days of initiation of treatment.
Gerhardt R.The accidental introduction of West Nile Virus into New York City from the Old World in 1999 resulted in an epidemic in humans, horses, and birds that swept to the west coast in just 3 years. The virus is transmitted by infective mosquitoes among susceptible native birds, which serve as amplifying hosts. Clinical disease occurs in humans and horses, but not enough virus is produced in their blood to infect other mosquitoes; therefore, humans and horses are considered dead-end hosts. Humans can best protect themselves by remaining indoors during periods of high mosquito activity and/or by using...
Carpio MM, Iversen JO.Leptospira interrogans serotype pomona antibody titres of 1:100 or greater were detected in 12.8% of 408 adult horses from seven of eight sampled herds in Saskatchewan. The geographical distribution of the seropositive horses was widespread throughout the agricultural area of the province. The geographical distribution and the cumulative increase in prevalence with age suggested that serotype pomona is enzootic in the equine population of Saskatchewan.