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.
Fischetti L, Perina F, Sarli G, Ellero N, Freccero F, Castagnetti C, Mariella J.A 286-day pregnant mare was referred for signs of impending abortion. The ultrasonographic evaluation revealed a high normal combined thickness of the utero-placental unit (CTUP), oligohydroallantois and a living fetus. No vulvar discharge was observed, and the cervical swab culture was negative. After a choke, the mare received NSAIDs and antibiotics and then developed systemic inflammatory response syndrome (SIRS) and aborted. The amniotic portion of the umbilical cord was excessively long and twisted and the chorionic side of the placenta showed a brown discoloration and rough surface area....
Martins AS, Romanowski TNA, Campos JS, Vieira RC, Silva TA, Borsanelli AC.Brucellosis is a zoonosis caused by bacteria of Brucella genus, which affects domestic and wild animals and humans. In horses, the infection can be caused by Brucella canis, Brucella suis or Brucella abortus, through the ingestion of contaminated food, contact of bacteria with skin wounds or through the respiratory tract, manifesting with signs such as fistulous withers and reduced performance. The present study aimed to evaluate the seroprevalence of Brucella abortus infection in equids in the state of Goiás. Sampling was carried out on 299 farms across 132 municipalities, with a total of 89...
Nadal C, Chanet C, Delaunay C, Pitel PH, Marsot M, Bonnet SI.Equine piroplasmosis, caused by the protozoan parasites Babesia caballi and Theileria equi, is endemic in Europe's Mediterranean basin, creating significant health and economic challenges for the equine sector. With no available vaccine, an eco-epidemiological approach is essential in order to identify and implement effective preventive measures. With this aim in view, we identified risk factors associated with B. caballi and T. equi infections and tick infestation for draught horses in the Auvergne-Rhône-Alpes region of France, known for its high piroplasmosis seroprevalence. During the spri...
Wilkins PA, Wong D, Slovis NM, Collins N, Barr BS, MacKenzie C, De Solis CN, Castagnetti C, Mariella J, Burns T, Perkins G, Delvescovo B, Sanchez LC....Sepsis has been defined in humans as the concurrent proven or suspected presence of microbial infection and the systemic inflammatory response syndrome (SIRS). Sepsis is the leading cause of morbidity and mortality in neonatal foals. The clinical utility of using SIRS or its individual components to predict infection and mortality in critically ill foals is currently unknown. Objective: Assess the ability of history and signalment, clinical findings, laboratory results, and SIRS-related indices to predict infection and mortality in critically ill foals. Methods: Retrospective, multi-center, cr...
McTernan SP, Heller J, Clulow JR, Gannon L, Huang R, Tidd N, Blishen A, Hughes KJ.Salmonella enterica subsp. enterica is responsible for substantial morbidity and mortality within horse populations, worldwide. The prevalence of Salmonella shedding in faeces has largely been reported in hospital settings, with limited information from general horse populations. Further, there is little understanding of the serotypes and antibiograms of Salmonella isolates from horses in Australia. The objectives of this study were to (1) estimate the prevalence of Salmonella in stud farm horse populations, (2) determine serotypes and antibiograms for isolates, and (3) determine whether seaso...
Cullinane A, Nelly M, Dayot L, Lukaseviciute G, Garvey M, Healy J, Gallagher R.This study describes a comparison of the detection of rotavirus in clinical samples from foals using two commercially available rapid antigen detection (RAD) kits, with the detection of rotavirus nucleic acid via a laboratory-based, in-house, real-time reverse transcription polymerase chain reaction (RT-PCR) assay. One hundred and forty freeze-thawed samples (70 that were RT-PCR-positive and 70 that were RT-PCR-negative on original tests) submitted to the diagnostic laboratory over a seven-year period were tested in addition to 123 fresh samples (15 RT-PCR-positive and 108 RT-PCR-negative) sub...
is the leading cause of acute gastroenteritis worldwide in young humans and animals. In 2023-2024, a relatively high rotavirus detection rate (34.5%) was detected in children with diarrhea in Caracas. All rotavirus strains were typed as P[8], using a multiplex RT-PCR assay, while the G-type was not identified. This unusual pattern, not previously observed in Venezuela, prompted the VP7 gene sequencing of nineteen strains, which displayed a high sequence identity (99.3-100%) compatible with the G3 genotype. These strains clustered into a well-supported lineage IX encompassing human reassortant...
Sun Y, Yu YT, Castillo XO, Anderson R, Wang M, Sun Q, Tallmadge R, Sams K, Reboul G, Zehr J, Brown J, Wang X, Marra N, Stanhope B, Grenier J....Fever of unknown origin (FUO) without a respiratory component is a frequent clinical presentation in horses. Multiple pathogens, both tick-borne and enteric, can be involved as etiologic agents. An additional potential mechanism is intestinal barrier dysfunction. This case-control study aimed to detect and associate microbial taxa in blood with disease state. Areas known for a high prevalence of tick-borne diseases in humans were chosen to survey horses with FUO, which was defined as fever of 101.5°F or higher with no signs of respiratory illness or other recognisable diseases. Blood samples ...
Wagner B, Schnabel CL, Rollins A.Equine herpesvirus type-1 (EHV-1) enters through the upper respiratory tract (URT) and causes respiratory disease, abortions, and myeloencephalopathy in equids. Pre-existing immunity at the viral entry site, especially mucosal IgG4/7 antibodies, has recently been shown to correlate with protection from disease and incomplete viral replication at the URT. Here, we tested whether intramuscular (i.m.) vaccination with a commercial inactivated EHV-1/4 vaccine can induce mucosal antibodies (mucAbs) at the URT. Methods: Adult horses with complete EHV-1 vaccination and/or exposure histories were vacc...
Yessinou RE, Farougou S, Olopade JO, Oluwayelu DO, Happi A, Happi C, Groschup M.Crimean-Congo hemorrhagic fever (CCHF) is a tick-borne zoonotic viral disease prevalent in Africa. While infection is asymptomatic in animals, it can cause severe illness with hemorrhagic manifestations and high mortality rates in humans. This study aimed to determine the seroprevalence and potential risk factors of CCHF in wild (rodents, birds) and domestic (cattle, horses) animals in Benin. A cross-sectional study was carried out from 2022 to 2024 with the assistance of cattle breeders, hunters, farmers and bushmeat sellers in 15 districts found in three agroecological zones in the country. ...
Godoi APDS, Sobral GG, da Silva Vieira JC, Carneiro GF, Conceição FR, da Silva ER, Mendonça M.Equine rhodococcosis is caused by Rhodococcus equi, an intracellular coccobacillus whose main virulence factor is a plasmid that harbors genes encoding proteins from the Vap family, with the vapA gene being the most important in equine isolates. Furthermore, other factors observed in R. equi strains, such as antimicrobial resistance and biofilm production, may represent significant challenges in the treatment of affected animals. The objective of this study was to characterize four isolates of R. equi from foals in the state of Pernambuco, Brazil. All isolates were identified as R. equi throug...
Brys M, Claerebout E, Saey V, Chiers K.A cross-sectional study was conducted to estimate the prevalence of chorioptic mange affecting the distal legs of horses in Belgium, focusing on the association between mange and chronic progressive lymphedema (CPL) in Belgian draft horses. Clinical examinations and skin scrapings were performed on the distal legs of 156 Belgian draft horses and 142 Belgian warmblood horses. In the Belgian draft horse breed, 144 (92.31%) horses were infested with Chorioptes bovis mites, and 126 (80.77%) displayed clinical signs of CPL. CPL prevalence in draft horses aged < 1 year was 17.86%, while mites we...
Hoerdemann M, Sahoo DK, Allbaugh RA, Kubai MA.To assess if an affordable, commercially available 275 nm ultraviolet C (UV-C) device can inhibit fungal pathogens associated with equine keratomycosis and to establish the optimal exposure time/dose required in vitro. Methods: Fungal inhibition zone surface areas of isolates from two fungal genera (Aspergillus and Fusarium spp.) were compared in triplicates after UV-C exposure at distances of 10, 15, and 20 mm with single or repeat doses (4 h apart) of 5, 10, 15, or 30 s duration after 24, 48, and 72 h of incubation. Inhibition zones were microscopically assessed, and regrowth chec...
Ichikawa Y, Iinuma Y, Okagawa T, Shimbo R, Enkhtuul B, Khurtsbaatar O, Kinoshita Y, Niwa H, Aoshima K, Kobayashi A, Batbaatar V, Ohashi K, Kimura T.Glanders is a World Organization for Animal Health (WOAH)-notifiable equine disease caused by the infection of Burkholderia mallei, and is endemic in Mongolia, South Asia, Africa, and South America. While the complement fixation test (CFT) has been widely used for serodiagnosis of glanders and is considered a standard serological test, it has several limitations. These limitations include poor specificity, labor intensive techniques, variability in antigen and protocol. Consequently, indirect enzyme-linked immunosorbent assays (iELISAs) based on recombinant proteins have been developed as alte...
Liu D, Zhao X, Wang X.Equine herpesvirus 1 (EHV-1), EHV-4, EHV-8, and EHV-9, are classified within the subfamily and are recognized as causative agents of respiratory, urogenital, and neurological disorders in horses. These viruses, collectively referred to as αEHVs, exhibits both unique and shared characteristics in terms of host interaction, pathogenesis, epidemiology, and immune evasion, which arise from both the identities and discrepancies among respective genomic homologs. The genomic architecture of αEHVs is similar to other members of the same subfamily, such as well-known HSV-1, VZV, and PRV. However, r...
Parashar R, Singla LD, Kaur P, Sharma SK.Relative association of haemato-biochemical findings with oxidative stress markers was evaluated between natural patent and latent infection of in horses to divulge the role of these parameters in the pathogenesis of illness due to non-availablity in literature. Blood samples were collected from 429 equines of 16 districts of the Punjab and samples positive by conventional microscopy (patent Group I; oll = 13), by polymerase chain reaction (PCR) (latent group II; = 38) and healthy control (group III, = 64) were compared for haematological-biochemical index and stress parameters....
Tsujimura K, Bannai H, Kambayashi Y, Nemoto M, Ohta M.Equid alphaherpesvirus 1 (EqAHV1; Orthoherpesviridae, Varicellovirus equidalpha1) spreads by viremia to susceptible organs. Because EqAHV1 circulates in the bloodstream in a cell-associated manner, serum samples are not considered valuable for detecting EqAHV1 and have therefore not been tested by highly sensitive detection methods such as real-time PCR (rtPCR). We investigated whether EqAHV1 could be detected by this method in equine serum samples. We performed rtPCR on archived sera and peripheral blood mononuclear cells (PBMCs) collected from 3 horses experimentally inoculated with EqAHV1. ...
Yu Y, Wang J, Ruan L, Chen L, Khan MZ, You A, Wang C, Li L, Ren H, Wang T, Liu W.Equid alphaherpesvirus type 8 (EHV-8) is a contagious pathogen that causes reproductive disorders, respiratory diseases, and viral encephalitis in equids, resulting in significant economic losses for the global horse and donkey industries. Currently, there are no approved antiviral drugs or vaccines available for EHV-8 control. In this study, we investigated the antiviral efficacy of celastrol against EHV-8 both in vitro and in vivo. Our results demonstrated that celastrol significantly inhibited EHV-8 infection in Rabbit kidney (RK-13) and equine dermal cells (NBL-6) in a dose-dependent manne...
McNabb L, McMahon A, Woube EG, Agnihotri K, Colling A, Broder CC, Kucinskaite-Kodze I, Petraityte-Burneikiene R, Bowden TR, Halpin K.Hendra virus (HeV) is a bat-borne zoonotic agent which can cause a severe and highly fatal disease and can be transferred from animals to humans. It has caused over 100 deaths in horses since it was discovered in 1994. Four out of seven infected humans have died. Since the release of the HeV vaccine (Equivac® HeV Hendra Virus Vaccine for Horses, Zoetis Australia Pty Ltd., Rhodes, NSW 2138) in Australia, there has been an urgent requirement for a serological test for differentiating infected from vaccinated animals (DIVA). All first-line diagnostic serological assays at the Australian Centre f...
Abdul-Latif SAK, Yousif AA.Strangles is a highly contagious equine respiratory disease caused by . It is a globally significant pathogen and one of the most common infectious agents in horses. In Iraq, no sequencing data on this pathogen are available, and only two molecular studies have been published to date. This study provides preliminary insights into strain diversity and provides a foundation for future large-scale investigations. Unassigned: This study aimed to investigate the molecular characteristics, identify gene alleles, and perform a phylogenetic analysis of isolates from horses in Baghdad, Iraq. Unassign...
Blomström AL, Källse A, Riihimäki M.Viral infections pose a significant challenge to the equine population, compromising welfare and causing substantial economic losses for the global equine industry. While numerous equine viral pathogens have been identified, many suspected viral infections remain undiagnosed. This highlights the need for further identification and characterization of viruses circulating within the equine population. In this study, we utilized viral metagenomics to investigate viruses present in serum samples and nasal swabs collected from horses in Sweden. The primary focus was on horses presenting with fever,...
Hardefeldt LY, Thomas K, Begg L.Antimicrobial resistance (AMR) is a problem for equine practitioners in Australia, but antimicrobial use in practice has been largely understudied. We aimed to evaluate equine veterinarians' intentions of prescribing antimicrobials in areas where we perceived there to be wide ranges of practice - dentistry, reproduction and for nonbactericidal effects. Methods: An online cross-sectional survey of veterinarians working in equine practice was conducted over 4 months in 2023 and 2024. Antimicrobial use, including compounding practices, for reproductive and dental disorders, and nonbactericidal...
Mohtasebi S, Ahn S, Rosa B, Moyes K, Kuzmina TA, Gilleard JS, Poissant J.Equids are infected by a diversity of gastrointestinal nematode parasites, including 64 species of equine strongyle nematodes from19 genera. Despite numerous surveys of horse strongyles worldwide, certain geographic regions and rare species remain understudied. In 1964, a new species of equine strongyle, Cylicocyclus pekingensis, was described from a donkey in China. Subsequently, this species was recorded in horses from Kazakhstan and reclassified as Hsiungia pekingensis (K'ung and Yang, 1964), the only species in this genus. Since then, H. pekingensis has not been reported elsewhere, with li...
Sheahan BJ, Schubert AG, Schubert W, Sheats MK, Schnabel LV, Gilbertie JM.Neutrophil extracellular traps (NETs) play a significant role in response to a variety of infectious and inflammatory stimuli in human and veterinary medicine. Although entrapment of bacteria can be an important function of NETs, the exuberant release of DNA and other intracellular molecules has also been negatively implicated in the pathogenesis of different diseases. Thus, NET formation must be tightly controlled and represents an opportunity for therapeutic interventions. Horses are particularly sensitive to bacterial stimuli that have previously been shown to cause NETs in other species, b...
Yuen NKY, Eng M, Hudson NJ, Sole-Guitart A, Coyle MP, Bielefeldt-Ohmann H.Our current understanding of the pathogenesis of Ross River virus (RRV) infection has been derived from murine models, which do not reproduce clinical disease as experienced by infected humans and horses. This prompted us to establish more relevant host model systems to study host-virus interactions using ex vivo peripheral blood mononuclear cells (PBMCs) and in vitro primary synovial fibroblast and epidermal keratinocyte cultures. Transcriptomic analysis revealed that the expression of the transmembrane protein matrix remodelling associated 8 (mxra8), recently found to be responsible for RRV ...
Shnaiderman-Torban A, Meltzer L, Zilberman-Daniels T, Navon-Venezia S, Cohen A, Sutton GA, Blum SE, Amit S, Steinman A.Infections with extended-spectrum beta-lactamase-producing Enterobacterales (ESBL-PE) contribute to morbidity and mortality in human neonates. In foals, data are scarce. Objective: Determine the association between ESBL-PE gastrointestinal colonization on hospital admission and infections in hospitalized neonates. Methods: Sixty-seven foals. Methods: Prospective study of foals admitted to a veterinary hospital. Foals were screened for ESBL-PE colonization and for infections. Risk factors and clinical outcomes were analyzed. Results: Seventy-six percent of foals suffered from at least 1 bacteri...
Sijtsema M, Stringer T, Hopman NEM, van der Graaf-van Bloois L, Duim B, van den Brom-Spierenburg A, Theelen M, Zomer A, Broens EM.Healthcare-associated infections (HAIs) associated with ESKAPEE pathogens are an emerging concern in equine hospitals, especially in the intensive care unit (ICU). To gain insight into the occurrence of HAIs and to identify potential reservoirs and transmission routes of ESKAPEE pathogens in an equine ICU, a pilot study of two periods (December 2022-January 2023 and April-June 2023) was performed, where patient and environmental samples were obtained upon ICU admission and discharge. A sampling and laboratory protocol for the detection and identification of different ESKAPEE pathogens and Salm...
Kelly RF, Galbraith E, Zahid O, Chaundhry U, Sargison N.Grazing animal species kept in zoological collections can be at risk of significant gastrointestinal nematode (GIN) infections. Little work has been undertaken to understand GIN species dynamics within co-grazed hosts. This study aimed to describe the species diversity of GINs found in faeces of grazing animals in a Scottish zoological collection. Methods: At a single time-point, freshly voided faecal samples were collected randomly from horses, sheep, goats, alpacas and deer. Faecal worm egg counts (FWECs) were conducted using a saturated saline centrifugal flotation cuvette technique. The ne...
Christie KD, Epstein KL, Tyma JF, Afonso T, Fultz LE, Giguère S.Surgical site infection (SSI) is an important complication following emergency celiotomy in the horse. Judicious antimicrobial use is important for the prevention of antimicrobial resistance and the limitation of antimicrobial-associated complications. Previous studies in horses have found no association between SSI and perioperative antimicrobial duration, but the ideal duration of antimicrobial administration in horses undergoing exploratory celiotomy remains unclear. Objective: To compare SSI and describe post-operative complications, survival, duration and cost of hospitalisation in horses...
Zhao Y, Holden VR, Smith RH, O'Callaghan DJ.The UL3 protein of equine herpesvirus 1 (EHV-1) KyA strain is a homolog of the ICP27 alpha regulatory protein of herpes simplex virus type 1 (HSV-1) and the ORF 4 protein of varicella-zoster virus. To characterize the regulatory function of the UL3 gene product, a UL3 gene expression vector (pSVUL3) and a vector expressing a truncated version of the UL3 gene (pSVUL3P) were generated. These effector plasmids, in combination with an EHV-1 immediate-early (IE) gene expression vector (pSVIE) and chimeric EHV-1 promoter-chloramphenicol acetyltransferase (CAT) reporter constructs, were used in trans...
Vázquez-Boland JA, Meijer WG.Rhodococcus equi is the only recognized animal pathogenic species within an extended genus of metabolically versatile Actinobacteria of considerable biotechnological interest. Best known as a horse pathogen, R. equi is commonly isolated from other animal species, particularly pigs and ruminants, and causes severe opportunistic infections in people. As typical in the rhodococci, R. equi niche specialization is extrachromosomally determined, via a conjugative virulence plasmid that promotes intramacrophage survival. Progress in the molecular understanding of R. equi and its recent rise as a nove...
Chan J, Doyle B, Branley J, Sheppeard V, Gabor M, Viney K, Quinn H, Janover O, McCready M, Heller J.In November 2014, New South Wales Health was notified of a cluster of respiratory illness in a veterinary school. Active case finding identified another case at a local equine stud. All cases had exposure to the equine fetal membranes of Mare A. This tissue subsequently tested positive for Chlamydia psittaci using quantitative real-time polymerase chain reaction. We conducted a cohort study of the university and stud farm staff to determine risk factors for disease. Nine people were exposed to the fetal membranes of Mare A. Of these, five cases of psittacosis were identified. Two required hosp...
Scott Weese J.Antimicrobial resistance (AMR) is an emerging problem in companion animals, because of difficult-to-treat infections, possible pressure to use antimicrobials that are important in human medicine, and potential zoonotic transmission. The extent and importance of AMR in companion animals are poorly understood, in part because of limited surveillance; however, it is clear that resistance is problematic in many pathogens and commensals, including staphylococci, enterococci, Escherichia coli and Salmonella.
McGuire TC, Tumas DB, Byrne KM, Hines MT, Leib SR, Brassfield AL, O'Rourke KI, Perryman LE.Cytotoxic T lymphocytes (CTL) can control some viral infections and may be important in the control of lentiviruses, including human immunodeficiency virus type 1. Since there is limited evidence for an in vivo role of CTL in control of lentiviruses, dissection of immune mechanisms in animal lentiviral infections may provide needed information. Horses infected with equine infectious anemia virus (EIAV) a lentivirus, have acute plasma viremia which is terminated in immunocompetent horses. Viremic episodes may recur, but most horses ultimately control infection and become asymptomatic carriers. ...
Nielsen MK, Vidyashankar AN, Andersen UV, Delisi K, Pilegaard K, Kaplan RM.Fecal analyses are becoming increasingly important for equine establishments as a means of parasite surveillance and detection of anthelmintic resistance. Although several studies have evaluated various egg counting techniques, little is known about the quantitative effects of pre-analytic factors such as collection and storage of fecal samples. This study evaluated the effects of storage temperature, storage time and airtight versus open-air storage on fecal egg counts. The experimental protocols were replicated in two study locations: Copenhagen, Denmark and Athens, Georgia, USA. In both loc...
Campbell AJ, Gasser RB, Chilton NB.In the current study, molecular techniques were evaluated for the species identification of individual strongyle eggs. Adult worms of Strongylus edentatus, S. equinus and S. vulgaris were collected at necropsy from horses from Australia and the U.S.A. Genomic DNA was isolated and a ribosomal transcribed spacer (ITS-2) amplified and sequenced using polymerase chain reaction (PCR) techniques. The length of the ITS-2 sequence of S. edentatus, S. equinus and S. vulgaris ranged between 217 and 235 nucleotides. Extensive sequence analysis demonstrated a low degree (0-0.9%) of intraspecific variation...
Nielsen MK, Vidyashankar AN, Olsen SN, Monrad J, Thamsborg SM.Nematodes belonging to the order Strongylida are ubiquitous in grazing horses, and the large strongyle Strongylus vulgaris is considered the most pathogenic. This parasite was originally described widely prevalent in equine establishments, but decades of frequent anthelmintic treatment appears to have reduced the prevalence dramatically. Increasing levels of anthelmintic resistance in cyathostomin parasites have led to implementation of selective therapy to reduce further development of resistance. It has been hypothesized that S. vulgaris could reoccur under these less intensive treatment cir...
Yuki N, Shimazaki T, Kushiro A, Watanabe K, Uchida K, Yuyama T, Morotomi M.Selective adhesion to only certain epithelia is particularly common among the bacterial members of the indigenous microflora of mammals. We have found that the stratified squamous epithelium of the nonsecreting area of horse stomach is colonized by gram-positive rods. The microscopic features of a dense layer of these bacteria on the epithelium were found to be similar to those reported in mice, rats, and swine. Adhering microorganisms were isolated and identified as Lactobacillus salivarius, L. crispatus, L. reuteri, and L. agilis by DNA-DNA hybridization and 16S rRNA gene sequencing techniqu...
Burrell MH, Wood JL, Whitwell KE, Chanter N, Mackintosh ME, Mumford JA.A longitudinal study of respiratory disease in racehorses was carried out to assess its relative associations with different infectious agents and to examine any role that the environmental conditions might play. The relationships between coughing, nasal discharge, pyrexia and lower respiratory tract disease were also examined to provide information for improving clinical diagnosis, particularly of disease of the lower respiratory tract. Lower airway disease was closely associated with infection with Streptococcus zooepidemicus. It was also found that equine herpesvirus seroconversions and S p...
Carpenter S, Evans LH, Sevoian M, Chesebro B.Equine infectious anemia virus was isolated from peripheral blood leukocytes collected during two early febrile cycles of an experimentally infected horse. RNase T1-resistant oligonucleotide fingerprint analyses indicated that the nucleotide sequences of the isolates differed by approximately 0.25% and that the differences appeared randomly distributed throughout the genome. Serum collected in the interval between virus isolations was able to distinguish the isolates by membrane immunofluorescence on live cells. However, no neutralizing antibody was detected in the interval between virus isola...
Derse D, Dorn PL, Levy L, Stephens RM, Rice NR, Casey JW.The long terminal repeats (LTRs) of equine infectious anemia virus (EIAV) were examined with respect to their ability to function as transcriptional promoters in various cellular environments. Nucleotide sequence analyses of the LTRs derived from two unique proviral clones revealed the requisite consensus transcription and processing signals. One of the proviruses possessed a duplication of a 16-base-pair sequence in the CCAAT box region of the LTR which was absent in the other provirus. To assess its functional activity, each LTR was coupled to the bacterial chloramphenicol acetyltransferase ...
Mancuso VA, Hope TJ, Zhu L, Derse D, Phillips T, Parslow TG.By systematically dissecting the Rev proteins of feline immunodeficiency virus (FIV) and equine infectious anemia virus (EIAV), we have identified within each a short peptide that is functionally interchangeable with the effector domains found in Rev-like proteins from other retroviruses. The active sequences from FIV and EIAV differ in several respects from other known effectors and may represent a distinct class of effector domain.
Qablan MA, Oborník M, Petrželková KJ, Sloboda M, Shudiefat MF, Hořín P, Lukeš J, Modrý D.Microscopic diagnosis of equine piroplasmoses, caused by Theileria equi and Babesia caballi, is hindered by low parasitaemia during the latent phase of the infections. However, this constraint can be overcome by the application of PCR followed by sequencing. Out of 288 animals examined, the piroplasmid DNA was detected in 78 (27·1%). Multiplex PCR indicated that T. equi (18·8%) was more prevalent than B. caballi (7·3%), while mixed infections were conspicuously absent. Sequences of 69 PCR amplicons obtained by the 'catch-all' PCR were in concordance with those amplified by the multiplex str...
Hoopes JT, Stark CJ, Kim HA, Sussman DJ, Donovan DM, Nelson DC.Streptococcus equi is the causative agent of the purulent infection equine strangles. This disease is transmitted through shedding of live bacteria from nasal secretions and abscess drainage or by contact with surfaces contaminated by the bacteria. Disinfectants are effective against S. equi, but inactivation by environmental factors, damage to equipment, and toxicity are of great concern. Bacteriophage-encoded lysins (cell wall hydrolases) have been investigated as therapeutic agents due to their ability to lyse susceptible gram-positive organisms. Here, we investigate the use of one lysin, P...
Giles RC, Donahue JM, Hong CB, Tuttle PA, Petrites-Murphy MB, Poonacha KB, Roberts AW, Tramontin RR, Smith B, Swerczek TW.Pathology case records of 3,514 aborted fetuses, stillborn foals, or foals that died < 24 hours after birth and of 13 placentas from mares whose foals were weak or unthrifty at birth were reviewed to determine the cause of abortion, death, or illness. Fetoplacental infection caused by bacteria (n = 628), equine herpesvirus (143), fungi (61), or placentitis (351), in which an etiologic agent could not be defined, was the most common diagnosis. Complications of birth, including neonatal asphyxia, dystocia, or trauma, were the second most common cause of mortality and were diagnosed in 19% of the...
Klaus C, Hörügel U, Hoffmann B, Beer M.During a routine examination of 130 horse sera from 13 herds in Thuringia one TBEV antibody positive serum - with a very high titre - could be detected. The horse had been bought from a holding in Bavaria, and was reported to have clinical signs that may have been caused by a TBEV infection. To identify the source of the suspected TBEV infection, ticks from the surroundings of the barn in Thuringia as well as horse sera and ticks from two herds in Bavaria were examined. In the holding in Bavaria, where the horse was kept before, two out of ten horse sera were found to be TBEV antibody positive...
Kotilainen T, Huhtinen M, Katila T.The objective of this study was to investigate the inflammatory reaction induced in the equine uterus by insemination with fresh and frozen semen. Eleven groups (6 to 8 mares per group) were studied during 2 breeding seasons. The mares were inseminated using raw semen, frozen semen, extended fresh and frozen semen, concentrated fresh semen, seminal plasma and seminal extenders only. One group was bred naturally. Six hours after insemination, the uteri were flushed with 50 ml of phosphate-buffered saline (PBS). Seventeen out of 104 samples (16%) exhibited slight bacterial growth. Neutrophil con...
Nielsen MK, Reinemeyer CR, Donecker JM, Leathwick DM, Marchiondo AA, Kaplan RM.Anthelmintic resistance is becoming increasingly prevalent among equine nematode parasites. The first reports documenting resistance were published in the 1960s, just a short time after introduction of the first modern anthelmintics phenothiazine and thiabendazole. Several factors are known to influence development of resistance, but evidence specific to equine parasites is limited. Most current knowledge and applications have been extrapolated from research with trichostrongylid parasites of sheep. The number of cyathostomin species co-infecting horses adds to the complexity of investigating ...
Schoster A, Staempfli HR, Guardabassi LG, Jalali M, Weese JS.Diarrhea in foals affects up to 60% of foals during the first six months of life. The effect of diarrhea on the fecal bacterial microbiota in foals has not been investigated. Little is known on the fecal bacterial microbial richness and diversity of foals at a young age. The objective was to compare the fecal bacterial microbiota of healthy foals to foals with diarrhea at two and four weeks of life. Methods: Fecal samples were collected from foals (n = 20) at 1-14 (T1) and 15-28 (T2) days of age and analyzed using high throughput sequencing. Differences in relative abundance of bacterial tax...
Havelaar AH, Furuse K, Hogeboom WM.In an attempt to explain the presence of F-specific (RNA) bacteriophages in waste-water, faecal material from humans and a variety of animals was examined. The phages were detected in appreciable numbers only in faeces from pigs, broiler chickens, sheep and calves but not from dogs, cows, horses and humans. Parallel examinations for somatic coliphages, thermotolerant coliforms, faecal streptococci and spores of sulphite-reducing clostridia revealed the consistent presence of these organisms in all types of samples, albeit in variable numbers. The number of F-specific bacteriophages was related...
Wagnerová P, Sak B, Květoňová D, Buňatová Z, Civišová H, Maršálek M, Kváč M.Faecal samples were collected from 377 horses on 23 farms with varying management systems in the Czech Republic. Microsporidia were found on 16 farms and the overall prevalence of Enterocytozoon bieneusi and Encephalitozoon cuniculi was 17.3% (66/377) and 6.9% (26/377), respectively. The prevalence of E. cuniculi in horses over 3 years of age was significantly higher (10.0%) compared to younger horses (4.0%). No significant differences in prevalence were observed among stallions, geldings, and mares for both microsporidia. Significantly higher infection rates of E. bieneusi and E. cuniculi wer...
Welch HM, Bridges CG, Lyon AM, Griffiths L, Edington N.The polymerase chain reaction (PCR) and co-cultivation were used to identify the lymphoreticular system as the site of latency of equid herpesvirus I (EHV-1). Primers for PCR were designed from aligned nucleotide sequences of the glycoprotein gB genes to amplify the same region of both the EHV-1 and EHV-4 genomes. Subsequent restriction digests using specific enzymes distinguished the amplified fragments of the EHV-1 genome from those of the EHV-4 genome. Ten weeks following an experimental infection of five ponies with EHV-1, latent virus was detected by PCR and recovered by co-cultivation, p...
Christensen M, Jacobsen S, Ichiyanagi T, Kjelgaard-Hansen M.Major acute phase proteins (APPs) have proven diagnostically useful in dogs, cats and horses with routine use facilitated by commercially available automated heterologous assays. An automated assay applicable across all three species would highly facilitate further dissemination of routine use, and the aim of this study was to validate an automated latex agglutination turbidimetric immunoassay based on monoclonal anti-human serum amyloid A (SAA) antibodies for measurement of canine, feline and equine SAA. Serum samples from 60 dogs, 40 cats and 40 horses were included. Intra- and inter-assay i...
Matthijnssens J, Miño S, Papp H, Potgieter C, Novo L, Heylen E, Zeller M, Garaicoechea L, Badaracco A, Lengyel G, Kisfali P, Cullinane A, Collins PJ....In this study, the complete genome sequences of seven equine group A rotavirus (RVA) strains (RVA/Horse-tc/GBR/L338/1991/G13P[18], RVA/Horse-wt/IRL/03V04954/2003/G3P[12] and RVA/Horse-wt/IRL/04V2024/2004/G14P[12] from Europe; RVA/Horse-wt/ARG/E30/1993/G3P[12], RVA/Horse-wt/ARG/E403/2006/G14P[12] and RVA/Horse-wt/ARG/E4040/2008/G14P[12] from Argentina; and RVA/Horse-wt/ZAF/EqRV-SA1/2006/G14P[12] from South Africa) were determined. Multiple novel genotypes were identified and genotype numbers were assigned by the Rotavirus Classification Working Group: R9 (VP1), C9 (VP2), N9 (NSP2), T12 (NSP3), ...
Palmer JL, Bertone AL.The use of extremely small dosages of intra-articular E. coli lipopolysaccharide (LPS) endotoxin can create a model of synovitis that mimics acute synovitis in horses. Dosages of 5000 ng, 25 ng, 0.5 ng, 0.25 ng, 0.17 ng and 0.125 ng per joint were injected into various joints of a total of 6 horses. The dose response of LPS on clinical signs and synovial fluid parameters was evaluated at baseline and 12, 24, 36 and 48 h after LPS injection. Peripheral venous blood analysis was performed at baseline and at 0, 4, and 12 h after LPS injection. Dosages greater than 0.5 ng/joint resulted in clinica...
Hammond SA, Li F, McKeon BM, Cook SJ, Issel CJ, Montelaro RC.Persistent infection of equids by equine infectious anemia virus (EIAV) is typically characterized by a progression during the first year postinfection from chronic disease with recurring disease cycles to a long-term asymptomatic infection that is maintained indefinitely. The goal of the current study was to perform a comprehensive longitudinal analysis of the course of virus infection and development of host immunity in experimentally infected horses as they progressed from chronic disease to long-term inapparent carriage. We previously described the evolution of EIAV genomic quasispecies (C...
Böer U, Lohrenz A, Klingenberg M, Pich A, Haverich A, Wilhelmi M.Decellularized equine carotid arteries (dEAC) may represent a reasonable alternative to alloplastic materials in vascular replacement therapy. Acellularity of the matrix is standardly evaluated by DNA quantification what however may not record sufficiently the degree of matrix immunogenicity. Thus, our aim was to analyze dEAC with a low DNA content for residual cellular proteins. A detergent-based decellularization protocol including endonuclease treatment resulted in dEAC with 0.6 ± 0.15 ng DNA/mg dry weight representing 0.33 ± 0.14% of native tissue DNA content. In contrast, when matrices ...
Diallo IS, Hewitson G, Wright L, Rodwell BJ, Corney BG.Equid herpesvirus 1 (EHV1) is a major disease of equids worldwide causing considerable losses to the horse industry. A variety of techniques, including PCR have been used to diagnose EHV1. Some of these PCRs were used in combination with other techniques such as restriction enzyme analysis (REA) or hybridisation, making them cumbersome for routine diagnostic testing and increasing the chances of cross-contamination. Furthermore, they involve the use of suspected carcinogens such as ethidium bromide and ultraviolet light. In this paper, we describe a real-time PCR, which uses minor groove-bindi...
Morein B, Blomqvist G, Hu K.The maintenance of pregnancy requires suppression of the maternal immune system which would naturally recognize the developing fetus as an allograft and seek to destroy it by mounting a Th1 regulated cytotoxic immune response. During pregnancy a range of soluble factors are produced by the placenta which switch maternal immune regulation towards a protective Th2 phenotype. These factors also influence the developing fetal immune system and all newborns initially have an immunological milieu skewed towards Th2 immunity. Vaccination during the neonatal period must therefore overcome the dual cha...
