Pathogenesis in horses refers to the biological mechanisms that lead to the development and progression of diseases within equine species. This process involves a complex interaction between the horse's immune system, genetic predispositions, environmental factors, and infectious agents such as bacteria, viruses, or parasites. Understanding pathogenesis is essential for identifying how diseases manifest and progress in horses, which can inform diagnostic and therapeutic strategies. Research in this area often focuses on specific diseases, examining factors such as pathogen entry, immune response, tissue damage, and recovery processes. This page compiles peer-reviewed research studies and scholarly articles that explore the mechanisms, contributing factors, and implications of pathogenesis in equine health.
Jurisic L, Auerswald H, Marcacci M, Di Giallonardo F, Coetzee LM, Curini V, Averaimo D, Ortiz-Baez AS, Cammà C, Di Teodoro G, Richt JA, Holmes EC....Members of the RNA virus order infect hosts ranging from marine invertebrates to terrestrial mammals. As such, understanding the determinants of host range in this group of viruses, as well as their patterns of emergence and disease potential, is of clear importance. The are a recently documented family within the . To date, mesoniviruses have only been associated with the infection of arthropod species, particularly mosquitoes, and hence are regarded as insect-specific viruses (ISVs). Herein, we report the first detection of a mesonivirus-Alphamesonivirus-1 -in mammals. Specifically, we uti...
Kabir A, Kelley WG, Glover C, Erol E, Helmy YA.Salmonella is a foodborne pathogen that poses a significant threat to global public health. It affects several animal species, including horses. Salmonella infections in horses can be either asymptomatic or cause severe clinical illness. Infections caused by Salmonella are presently controlled with antibiotics. Due to the formation of biofilms and the emergence of antimicrobial resistance, the treatment has become more complicated. Our study focused on investigating the prevalence of Salmonella enterica in necropsied horses, assessing the capability for biofilm formation, and motility, determi...
Parashar B, Malviya R, Sridhar SB, Wadhwa T, Talath S, Shareef J.Eastern equine encephalitis virus (EEEV) is a lethal transmitted by mosquitoes that primarily cycles between birds. Although rare, infections in humans and horses are associated with high mortality rates and severe neurological effects. Climate change appears to be increasing the spread of this virus. This study aims to provide a comprehensive analysis of EEEV, including its transmission dynamics, pathogenesis, induced host immune response, and long-term impacts on survivors. It also highlights the virus's unique immune evasion strategies that complicate disease management and contribute to ...
Mohamed E, Zarak I, Vereecke N, Theuns S, Laval K, Nauwynck H.Varicellovirus equidalpha 1, formerly known as Equid alphaherpesvirus 1 (EHV-1), is highly prevalent and can lead to various problems, such as respiratory problems, abortion, neonatal foal death, and neurological disorders. The latter is known as equine herpes myeloencephalopathy (EHM). Cases of EHM have significantly increased since the beginning of the twenty-first century. The genomic sequences of five isolates associated with the fatal neurological outbreak in Valencia, Spain, in 2021 were analyzed and documented. The genome and replication kinetics of the Belgian EHM isolate 21P40, associ...
Jensen A, Clarke EJ, Nugent Z, Paice E, Gringel I, Yamamoto K, Rocchigiani G, Peffers AJ, Cooper L, Peffers MJ.Equine dental diseases significantly impact a horse's overall health, performance and quality of life. They can result in secondary infections and digestive disturbances, potentially leading to colic. A recently described disease affecting the incisors of horses is equine odontoclastic tooth resorption and hypercementosis (EOTRH). Understanding EOTRH is crucial for early diagnosis, effective management and prevention of its severe consequences. Objective: To determine proteomic differences in incisor cementum in horses with and without clinical EOTRH. Methods: Comparative and observational cli...
Pradhan SS, Balena V, Bera BC, Anand T, Khetmalis R, Madhwal A, Kandasamy S, Pavulraj S, Bernela M, Mor P, Tripathi BN, Virmani N.Equine herpesvirus type 1 (EHV1) is a ubiquitous viral pathogen infecting the equine population worldwide. EHV1 infection causes respiratory illness, abortion, neonatal foal mortality, and myeloencephalopathy. The currently available modified live EHV1 vaccines have safety and efficacy limitations. The two mutant EHV1 viruses (vToH-DMV (∆IR6/gE) and vToH-QMV (∆IR6/UL43/gE/UL56)), generated by the deletion of genes responsible for virulence (gE and IR6) and immunosuppression (uL43 and uL56), have been previously characterized by our group and found to generate good immune responses. The pre...
Carvalho Serena G, Marchezan Piva M, Viezzer Bianchi M, Fernandes da Fonseca HC, Chitolina Pupin R, Martins Basso R, Secorun Borges A....In horses, systemic calcinosis is a rare syndrome characterised by muscle lesion associated with the mineralisation of large muscle groups or other organs, in the absence of an alternative cause for the calcification, such as toxic, enzootic or metabolic. Molecular and histopathological aspects of the disease are still poorly elucidated. Objective: To describe the epidemiological, pathological and molecular aspects of systemic calcinosis in a convenience sample of six horses submitted to necropsy in the Southern and Midwestern regions of Brazil. Methods: Retrospective exploratory study. Method...
Gerras J, Young K, Roberts D, Waldman G, Salmon JH, Gilger BC.To describe the ocular findings, chronology of disease, and serum leptospiral titers in a group of horses, mules, and donkeys following an outbreak of leptospirosis. Unassigned: Fifty Equidae in central North Carolina had ophthalmic examinations and serum leptospiral microscopic agglutination test (MAT) titers performed every 3-6 months for 24 months followed by a final examination at 34 months. Unassigned: Throughout the nearly three-year study period, 17 horses (34%; 17/49 horses) developed signs of uveitis; 20 eyes (20/34; 58.8%) of these 17 horses were visual at the initial examinati...
Styková E, Valocký I, Kačírová J, Fecskeová LK.Equine pastern dermatitis (EPD) is a multifactorial disease with a change in the skin microbiome. The present study monitored the influence of Weissella cibaria Biocenol™ 4/8 D37 CCM 9015 stabilized on alginite on the skin microbiota of healthy horses and model patients with EPD. Based on clinical signs, EPD lesions were identified as exudative or proliferative forms. A comparison of the initial microbial community based on 16S rRNA amplicon sequencing revealed that there was a statistically significant difference between healthy vs. exudative (R = 0.52, p = 0.003) and exudative vs. ...
Monecke S, Burgold-Voigt S, Feßler AT, Krapf M, Loncaric I, Liebler-Tenorio EM, Braun SD, Diezel C, Müller E, Reinicke M, Reissig A, Cabal Rosel A....Leukocidins of (.) are bicomponent toxins that form polymeric pores in host leukocyte membranes, leading to cell death and/or triggering apoptosis. Some of these toxin genes are located on prophages and are associated with specific hosts. The genes have been described from equine isolates. We examined the genomes, including the prophages, of strains belonging to clonal complexes CC1, CC350, CC816, and CC8115. In addition to sequencing, phages were characterised by mitomycin C induction and transmission electron microscopy (TEM). All prophages integrated into the = gene, and all included...
Ishikawa Y, Tufa SF, Keene DR, Bächinger HP, Winand NJ.Mutations in the collagen-modifying enzyme lysyl hydroxylase 1 (LH1) cause Warmblood Fragile Foal Syndrome (WFFS) in horses. We investigated the impact of this mutation on collagen structure and function. Our results show that LH1 deficiency leads to reduced lysine hydroxylation, altered collagen fibril organization, and tissue abnormalities resembling human Ehlers-Danlos syndrome. These findings highlight the critical role of LH1 in collagen biosynthesis and provide insights into the pathogenesis of WFFS.
Hrala M, Andrla P, Bosák J, Fedrová P, Mugutdinov A, Karpíšková R, Nedbalcová K, Raichová J, Faldyna M, Hořín P, Šmajs D.Taylorella equigenitalis is the causative agent of sexually transmitted contagious equine metritis. Infections manifest as cervicitis, vaginitis and endometritis and cause temporary infertility and miscarriages of mares. While previous studies have analyzed this organism for various parameters, the evolutionary dynamics of this pathogen, including the emergence of antibiotic resistance, remains unresolved. The aim of this study was to isolate contemporary strains, determine their genome sequences, evaluate their antibiotic resistance and compare them with other strains. We determined nine comp...
Vinijkumthorn R, Kingkaw A, Yanyongsirikarn P, Phaonakrop N, Roytrakul S, Vongsangnak W, Tesena P.Equine melanocytic neoplasm (EMN) represents a form of skin tumor observed predominantly in grey horses aged over 15 years. Despite its prevalence, current therapeutic and preventive strategies for EMN have been subject to limited investigation. This study endeavors to shed light on potential phosphoproteins present in equine serum and fecal samples, potentially linked to EMN, with a specific focus on functional interactions in EMN pathogenesis. We examined 50 samples (25 serum, 25 feces), divided into three groups based on EMN severity: normal (n = 16), mild (n = 18), and severe EMN (...
Hermans LM, Bonsergent C, Josson A, Rocafort-Ferrer G, Le Guyader M, Angelloz-Pessey S, Leblond A, Malandrin L.Equine piroplasmosis is a tick-borne disease mainly caused by Theileria equi and Babesia caballi. The objectives of this study were to analyse the frequency and routes of vertical transmission of these blood parasites from 179 asymptomatic mares to their foals. Foals were sampled within 72 h post-partum. The seroprevalences determined by Indirect Immunofluorescent Antibody Test (IFAT) and based on a subset sample of 107 couples, were 59.8% and 42.1% for T. equi and B. caballi, respectively in the mare population, and 54.2% and 40.2% in the foal population. A species-specific nested PCR was per...
Equine infectious anemia virus (EIAV) is the simplest described within the family, related to the human immunodeficiency viruses (HIV-1 and HIV-2). There is an important interplay between host cells and viruses. Viruses need to hijack cellular proteins for their viral cycle completion and some cellular proteins are antiviral agents interfering with viral replication. HIV cellular partners have been extensively studied and described, with a special attention to host proteins able to inhibit specific steps of the viral cycle, called restriction factors. Viruses develop countermeasures against ...
Koziy RV, Katselis GS, Yoshimura S, Simko E, Bracamonte JL.Prompt diagnosis of equine septic arthritis is crucial for successful treatment. Serum amyloid A (SAA) has been suggested as a reliable biomarker. However, we previously found that synovial fluid SAA increases in nonaffected joints of horses with septic arthritis. We hypothesized that systemic SAA may leak into the nonaffected joints. If this is the case, we also hypothesized that locally produced joint SAA isoforms may be better candidates for septic arthritis biomarkers. Thus, our objectives were 1) to evaluate the temporal kinetics of systemic and synovial fluid SAA in horses with septic ar...
Toft K, Honoré ML, Ripley N, Nielsen MK, Mardahl M, Fromm B, Hedberg-Alm Y, Tydén E, Nielsen LN, Nejsum P, Thamsborg SM, Cirera S, Pihl TH.The equine bloodworm, Strongylus vulgaris, is a common and highly pathogenic parasite in horses due to its migratory life cycle involving the intestinal arteries. Current diagnostic techniques cannot detect the prepatent migrating stages of S. vulgaris, highlighting the need for new biomarkers. Parasites release microRNAs (miRNAs) into their environment, which could potentially be detectable in host blood samples. Additionally, host miRNA expression patterns may change in response to infection. This study aimed to identify miRNAs associated with S. vulgaris infection by profiling the horse's m...
François AC, Renaud B, Kruse CJ, Marcillaud-Pitel C, Votion DM.Anne-Christine François, Benoît Renaud, Caroline-Julia Kruse, Christel Marcillaud-Pitel and Dominique-Marie Votion of the Atypical Myopathy Alert Group discuss insights from 20 years of research and surveillance on equine atypical myopathy.
Guest DJ, Birch HL, Thorpe CT.The suspensory ligament (SL) is a key component of the elaborate and highly adapted suspensory apparatus in the horse. In addition to contributing to stabilisation of the metacarpophalangeal joint, the SL has a spring like function to reduce the energetic cost of locomotion. Although the SL is highly prone to injury in horses of all ages and competing in a wide range of disciplines, knowledge regarding fundamental structure-function relationships in the SL is lacking, particularly compared with other injury-prone tendinous structures such as the superficial digital flexor tendon. In this revie...
Hain-Saunders N, Knight DR, Bruce M, Riley TV.Recent increases in community-associated Clostridioides difficile infections have highlighted the importance of monitoring toxigenic C. difficile from animal and environmental sources. We provide the complete circularized genomes of two toxigenic C. difficile strains isolated from feral horse faeces. Genome N64 (sequence type 964) consists of a single chromosome of 4,078,791 bp, while genome H251 (sequence type 963) comprises one chromosome (4,304,722 bp) and three plasmids (150,942 bp, 11,534 bp, and 9,074 bp).
Rodrigues GG, Alves DS, Bromberger CR, Nomelini QSS, Borges AS, de Oliveira-Filho JP, Delfiol DJZ.The association between aural plaques, Equus caballus papillomavirus (EcPV), and the different breeds of horses and risk factors is poorly described. The objective of this study was to determine the clinical prevalence of aural plaques in Mangalarga Marchador (MM) and Quarter Horse (QH) horses in Brazil, to evaluate the association of this prevalence with some risk factors, and to detect the presence of EcPV DNA (types 1-10) in aural plaques biopsies. A total of 400 MM and 425 QH horses, were clinically evaluated. For each horse, an identification form was completed, containing information on ...
Botía M, Martín-Cuervo M, Martínez-Subiela S, Cerón JJ, Ayala I, Hansen S, Muñoz-Prieto A.Equine Gastric Ulcer Syndrome (EGUS) is a widespread disease with a very high prevalence and importance in horses. It includes two conditions: Equine squamous gastric disease (ESGD), linked to acid disturbances, and Equine Glandular Gastric Disease (EGGD), associated with inflammation and immune system issues. In saliva, increased levels of immunological markers have been observed in this disease, indicating immune system involvement. In addition, changes in biomarkers of oxidative stress have been described. In horses, IgG and IgA are proteins that appear in saliva and serum and are considere...
Gagliardi R, Koch DW, Loeser R, Schnabel LV.Osteoarthritis (OA) is a debilitating disease that impacts millions of individuals and has limited therapeutic options. A significant hindrance to therapeutic discovery is the lack of in vitro OA models that translate reliably to in vivo preclinical animal models. An alternative to traditional inflammatory cytokine models is the matrikine stimulation model, in which fragments of matrix proteins naturally found in OA tissues and synovial fluid, are used to stimulate cells of the joint. The objective of this study was to determine if matrikine stimulation of equine synovial fibroblasts and chond...
Ryu SH, Jang B, Kim BS, Park KT.This is the first report describing the isolation and genome sequence of Flavobacterium ceti (F. ceti IJFC025) from a draining submandibular lymph node abscess in a 6-year-old mixed-breed mare in Korea. Since F. ceti is not a usual infectious pathogen that causes equine health problems, this study presents the complete genome sequence of F. ceti isolated from a submandibular lymph node abscess sample in Jeju, South Korea, in 2022. The entire genome sequence of F. ceti IJFC025 consisted of a 3,144,426-bp chromosome with 35.6 % G + C content. Gene prediction revealed that this strain possesse...
Luan Y, Zhong L, Li C, Yue X, Ye M, Wang J, Zhu Y, Wang Q.Polydactyly was recorded before 100 BCE and attracted widespread interest because of its relationship to limb health and ancestral traits in horses. However, the underlying reasons for the development of polydactyly remain unclear. To search for polydactyly-related genes, we utilize a paternal half-sib family and screen for variants that match the mode of inheritance. Through this screening process, 77 variants in 65 genes are filtered. A missense variant (EqCab3.0 chr4: <107353368> A > G) (rs1138485164) in the 3rd exon of LMBR1 is identified as a source of amino acid sequence variatio...
Muñoz-Prieto A, Rubić I, Rešetar Maslov D, González-Sánchez JC, Mrljak V, Cerón JJ, Hansen S.Equine gastric ulcer syndrome (EGUS) is a common condition in horses. This study explores the use of liquid proteomics to identify new biomarkers in saliva and serum to monitor EGUS treatment. The proteomes of horses with EGUS before and after a successful treatment with omeprazole were analysed. In saliva, 503 proteins were identified, with 7 upregulated and 6 downregulated post-treatment. Among the proteins that changed, there was an increase in vimentin, linked to wound healing, and a decrease in podocalyxin, associated with tissue damage. In serum, 206 proteins were found, with significant...
Köhne M, Hüsch R, Tönissen A, Schmidt M, Müsken M, Böttcher D, Hirnet J, Plötz M, Kittler S, Sieme H. subspecies (subsp.) is an important facultative pathogen in horses and can cause severe infections in other species including humans. Facing the post-antibiotic era, novel antimicrobials are needed for fighting bacterial infections. Bacteriophages (phages) are the natural predators of bacteria and discussed as a promising antimicrobial treatment option. The objective of this study was to isolate and characterize subsp. specific phages for the first time and to evaluate their efficacy and . In total, 13 phages with lytic activity were isolated and host ranges were determined. Two phages wit...
Kambayashi Y, Nemoto M, Ochi A, Kishi D, Ueno T, Tsujimura K, Bannai H, Kawanishi N, Ohta M, Suzuki T.In this study, equine intestinal enteroids (EIEs) were generated from the duodenum, jejunum, and ileum and inoculated with equine coronavirus (ECoV) to investigate their suitability as in vitro models with which to study ECoV infection. Immunohistochemistry revealed that the EIEs were composed of various cell types expressed in vivo in the intestinal epithelium. Quantitative reverse-transcription PCR (qRT-PCR) and virus titration showed that ECoV had infected and replicated in the EIEs. These results were corroborated by electron microscopy. This study suggests that EIEs can be novel in vitro ...
Manikantan V, Ripley NE, Nielsen MK, Dangoudoubiyam S.Parascaris spp. represent a significant threat to equine health worldwide, particularly in foals. The long-term survival of parasites in the host necessitates persistent modulation of the host immune response. Intercellular communication achieved through the exchange of molecules via extracellular vesicles (EVs) released from the parasite could be a crucial factor in this regard. This study aimed to isolate and characterize EVs released by adult male and female Parascaris worms and conduct a proteomic analysis to identify sex-specific proteins and potential immunomodulatory factors. Methods: L...
Ríos Carrasco M, Gröne A, van den Brand JMA, de Vries RP.Influenza A viruses (IAVs) from the H5N1 2.3.4.4b clade are circulating in dairy farms in the USA.; ruminants were presumed not to be hosts for IAVs. Previously, IAV-positive mammalian species were hunters and scavengers, possibly getting infected while feeding on infected birds. It is now recognized that H5N1 viruses that circulate in US dairy cattle transmit through a mammary gland route, in contrast to transmission by aerosols via the respiratory tract. The sialome in the cow mammary and respiratory tract is so far solely defined using plant lectins. Here, we used recombinant HA proteins re...
Rebordão MR, Carneiro C, Alexandre-Pires G, Brito P, Pereira C, Nunes T, Galvão A, Leitão A, Vilela C, Ferreira-Dias G.Besides the classical functions, neutrophils (PMNs) are able to release DNA in response to infectious stimuli, forming neutrophil extracellular traps (NETs) and killing pathogens. The pathogenesis of endometritis in the mare is not completely understood. The aim was to evaluate the in vitro capacity of equine PMNs to secrete NETs by chemical activation, or stimulated with Streptococcus equi subspecies zooepidemicus (Szoo), Escherichia coli (Ecoli) or Staphylococcus capitis (Scap) strains obtained from mares with endometritis. Ex vivo endometrial mucus from mares with bacterial endometritis wer...
Carpenter S, Chesebro B.Similar to other human and animal lentiviruses, equine infectious anemia virus (EIAV) is detectable in vivo in cells of the monocyte-macrophage lineage. Owing to their short-lived nature, horse peripheral blood macrophage cultures (HMC) are rarely used for in vitro propagation of EIAV, and equine dermal (ED) or kidney cell cultures, which can be repeatedly passed in vitro, are used in most studies. However, wild-type isolates of EIAV will not grow in these cell types without extensive adaptation, a process which may attenuate viral virulence. To better define the effect of host cell tropism on...
Mumford JA, Hannant D, Jessett DM.Infection of seronegative Welsh mountain ponies was established by intranasal instillation or exposure to nebulised aerosol of egg grown H3N8 viruses. Pyrexia and coughing were noted following intranasal instillation and high titres of virus were recovered from the nasopharynx. Exposure to aerosol resulted in more severe clinical signs characterised by high temperatures, dyspnoea, anorexia and coughing; lower levels of virus were recovered from the nasopharynx. The severity of clinical signs and the kinetics of virus shedding were dose-related with the minimal infectious dose being 10(2)EID50/...
Fortier G, van Erck E, Pronost S, Lekeux P, Thiry E.Equine gammaherpesviruses (γEHV) have been widely studied over the past 45 years and many isolates have been characterised. Despite this, the diagnosis of γEHV infection remains difficult to establish as its clinical manifestations lack specificity, ranging from mild respiratory signs in a small number of animals to outbreaks in large groups of young horses. This review focuses on the epidemiology, pathogenesis, clinical manifestations and diagnosis of equine herpesvirus (EHV)-2 and -5 infections, as well as on the genetic variation of these viruses. Study of these variations has resulted in...
Kawcak CE, McIlwraith CW, Norrdin RW, Park RD, James SP.Subchondral bone plays a role in the pathogenesis of osteochondral damage and osteoarthritis in horses and humans. Osteochondral fragmentation and fracture, subchondral bone necrosis and osteoarthritis are common diseases in athletic horses, and subchondral bone is now thought to play an integral role in the pathogenesis of these diseases. There have been numerous research efforts focused on articular cartilage damage and its pathogenesis, yet comparatively little effort focused on subchondral bone pathology or the coordinated disease states of the osteochondral tissues. The purpose of this re...
Pusterla N, Hussey GS.Equine myeloencephalopathy (EHM), an uncommon manifestation of equine herpesvirus 1 (EHV-1) infection, can cause devastating losses on individual farms, boarding stables, veterinary hospitals, and show and racing venues. An improved understanding of EHM has emerged from experimental studies and from data collected during field outbreaks at riding schools, racetracks, horse shows, and veterinary hospitals throughout North America and Europe. These outbreaks have highlighted the contagious nature of EHV-1 and have prompted a reevaluation of diagnostic procedures, treatment modalities, preventati...
Weiss M, Horzinek MC.In equine dermis cells infected with Berne virus particles were first detected 10 h after infection. Virions were encountered in all parts of the Golgi system and, infrequently, in the rough endoplasmic reticulum. A unique form of budding of preassembled rigid tubular nucleocapsids was demonstrated. Masses of tubular nucleocapsids of a lesser diameter and electron density were prominent in the cytoplasm and the nucleus of infected cells. Within the Golgi system and cytoplasmic cisternae virions appeared as straight or slightly curved rods. Extremely long, aberrant virions (250 nm) were occasio...
McFarlane D, Dybdal N, Donaldson MT, Miller L, Cribb AE.Equine pituitary pars intermedia dysfunction (PPID) is a spontaneously occurring progressive disease affecting aged horses and ponies. The pathogenesis of PPID is poorly understood, but the available evidence supports a loss of dopaminergic inhibition of the melanotropes of the pars intermedia. Horses with PPID have increased plasma concentrations of pars intermedia pro-opiomelanocortin-derived peptides that decrease in response to dopamine or dopamine agonist administration. Dopamine and dopamine metabolite concentrations are decreased in the pars intermedia of affected horses compared to age...
Gerber V, Lindberg A, Berney C, Robinson NE.Mucus accumulation and neutrophilic inflammation in the airways are hallmarks of heaves. Endoscopically visible mucus accumulations, however, have not been studied during exposure to dusty hay and allergens (ie, environmental challenge). We hypothesized that (1) heaves-affected horses have increased mucus accumulation compared with controls, (2) mucus accumulations increase in heaves-affected horses during environmental challenge, and (3) environmental challenge also induces neutrophilic inflammation and mucus accumulation in control horses. Mucus accumulation was graded endoscopically (mucus ...
Verma A, Stevenson B, Adler B.Leptospirosis in horses has been considered a relatively uncommon infection. However, recent data suggest that the infection is widespread, with the incidence and infecting serovars varying considerably in different geographical regions. The majority of infections remain asymptomatic. Clinical signs in equine leptospirosis resemble those seen in other animal species. However, leptospirosis as a cause of acute respiratory distress is becoming more frequently recognised. A particular feature of equine leptospirosis is post infection recurrent uveitis (moon blindness or periodic ophthalmia), whic...
Denoix JM.Knowledge of the normal functional behavior and mechanical properties of the vertebral column is important to understand the pathogenesis of back lesions, to identify the clinical manifestations of back pain, and to ensure a rational approach to physical therapy. The purpose of this article is to present a synthesis of in vivo and in vitro data obtained from different but complementary investigations. Presently, in vivo studies are limited; few gait-specific kinematic and electromyographic investigations are in process. Higher stresses to reach the maximal range of intervertebral motion can be...
de Jong NWM, Vrieling M, Garcia BL, Koop G, Brettmann M, Aerts PC, Ruyken M, van Strijp JAG, Holmes M, Harrison EM, Geisbrecht BV, Rooijakkers SHM.Staphylococcus aureus is a versatile pathogen capable of causing a broad range of diseases in many different hosts. S. aureus can adapt to its host through modification of its genome (e.g. by acquisition and exchange of mobile genetic elements that encode host-specific virulence factors). Recently, the prophage φSaeq1 was discovered in S. aureus strains from six different clonal lineages almost exclusively isolated from equids. Within this phage, we discovered a novel variant of staphylococcal complement inhibitor (SCIN), a secreted protein that interferes with activation of the human complem...
Côté O, Clark ME, Viel L, Labbé G, Seah SY, Khan MA, Douda DN, Palaniyar N, Bienzle D.Secretoglobin family 1A member 1 (SCGB 1A1) is a small protein mainly secreted by mucosal epithelial cells of the lungs and uterus. SCGB 1A1, also known as club (Clara) cell secretory protein, represents a major constituent of airway surface fluid. The protein has anti-inflammatory properties, and its concentration is reduced in equine recurrent airway obstruction (RAO) and human asthma. RAO is characterized by reversible airway obstruction, bronchoconstriction and neutrophilic inflammation. Direct effects of SCGB 1A1 on neutrophil functions are unknown. We have recently identified that the SC...
Allen GP, Breathnach CC.Neurological disease in horses caused by infection with certain 'paralytic' strains of equine herpesvirus-1 (EHV-1) is a potentially devastating condition the pathogenesis of which is poorly understood. Preliminary observations in both experimentally induced and naturally occurring cases of the central nervous system disease have revealed a more robust cell-associated viraemia in horses infected with paralytic isolates of EHV-1, relative to horses infected with abortigenic isolates. To investigate further this pathogenesis-relevant question, the present study was performed using a greater numb...
Yager JA.The pathogenesis of Rhodococcus equi pneumonia in foals is reviewed. The main routes of infection are respiratory and alimentary. The latter is probably the chief route of exposure in all foals and probably leads to development of specific immunity. Susceptible foals, those whose maternal immunity wanes before generation of their own immune response, readily develop disease if exposed aerogenously to sufficient numbers of R. equi. Management and environmental circumstances have a major role to play in determining the magnitude of this challenge and, therefore, in the prevalence of the disease....
Mumford JA, Wilson H, Hannant D, Jessett DM.Equine influenza vaccines containing inactivated whole virus and Carbomer adjuvant stimulated higher levels and longer lasting antibody to haemagglutinin in ponies than vaccines of equivalent antigenic content containing aluminium phosphate adjuvants. Five months after the third dose of vaccine containing Carbomer adjuvant, ponies were protected against clinical disease induced by an aerosol of virulent influenza virus (A/equine/Newmarket/79, H3N8). In contrast ponies which received vaccine containing aluminium phosphate adjuvant were susceptible to infection and disease. There was an inverse ...
Ríos Carrasco M, Gröne A, van den Brand JMA, de Vries RP.Influenza A viruses (IAVs) from the H5N1 2.3.4.4b clade are circulating in dairy farms in the USA.; ruminants were presumed not to be hosts for IAVs. Previously, IAV-positive mammalian species were hunters and scavengers, possibly getting infected while feeding on infected birds. It is now recognized that H5N1 viruses that circulate in US dairy cattle transmit through a mammary gland route, in contrast to transmission by aerosols via the respiratory tract. The sialome in the cow mammary and respiratory tract is so far solely defined using plant lectins. Here, we used recombinant HA proteins re...
Taylor KG, Paessler S.Equine encephalids have high mortality rates and represent a significant zoonotic public health threat. Of these the most pathogenic viruses to equids are the alphaviruses in the family Togaviridae. The focus of this review Venezualen equine encephalitis virus (VEEV) has caused the most widespread and recent epidemic outbreaks of disease. Circulation in naturally occuring rodent-mosquito cycles, results in viral spread to both human and equine populations. However, equines develop a high titer viremia and can transmit the virus back to mosquito populations. As such, the early recognition and c...
Soboll Hussey G, Hussey SB, Wagner B, Horohov DW, Van de Walle GR, Osterrieder N, Goehring LS, Rao S, Lunn DP.Equine herpesvirus-1 (EHV-1) infection remains a significant problem despite the widespread use of vaccines. The inability to generate a protective immune response to EHV-1 vaccination or infection is thought to be due to immunomodulatory properties of the virus, and the ORF1 and ORF2 gene products have been hypothesized as potential candidates with immunoregulatory properties. A pony infection study was performed to define immune responses to EHV-1, and to determine if an EHV-1 ORF1/2 deletion mutant (ΔORF1/2) would have different disease and immunoregulatory effects compared to wild type EH...
Risseti RM, Zastempowska E, Twarużek M, Lassa H, Pantoja JCF, de Vargas APC, Guerra ST, Bolaños CAD, de Paula CL, Alves AC, Colhado BS....Trueperella pyogenes is an opportunistic pathogen that causes diverse pyogenic infections in livestock. The genes that encode the exotoxin pyolysin (plo) and other putative factors that promote adhesion of pathogen to host cells (fimbriae fimA, fimC, fimE, fimG, neuraminidases nanH, nanP, and collagen-binding protein cbpA) have been associated with virulence, particularly in mastitis and uterus infections of dairy cows. However, the role of these virulence markers in the pathogenicity of the agent in domestic animals infections still is incompletely understood. The genes plo, fimA, fimC, fimE,...
Nichols AEC, Settlage RE, Werre SR, Dahlgren LA.Tendinopathies are common and difficult to resolve due to the formation of scar tissue that reduces the mechanical integrity of the tissue, leading to frequent reinjury. Tenocytes respond to both excessive loading and unloading by producing pro-inflammatory mediators, suggesting that these cells are actively involved in the development of tendon degeneration. The transcription factor scleraxis (Scx) is required for the development of force-transmitting tendon during development and for mechanically stimulated tenogenesis of stem cells, but its function in adult tenocytes is less well-defined. ...
Kitamoto N, Ramig RF, Matson DO, Estes MK.The production of viral antigen after infection of MA104, HepG2 (derived from human liver), and CaCo-2 (derived from human colon) cells with various cultivatable human and animal rotavirus strains was compared using immunofluorescence tests. All rotavirus strains examined expressed antigen in CaCo-2 cells and MA104 cells, but only some virus strains, namely, SA11-Cl3 (simian), RRV (simian), CU-1 (canine), and Ty1 (turkey), produced antigen in numbers of infected HepG2 cells comparable to infections in MA104 and CaCo-2 cells. Fl-14 (equine), OSU (porcine), NCDV (bovine), and Ch2 (chicken) strai...
Heim A, Passos LM, Ribeiro MF, Costa-Júnior LM, Bastos CV, Cabral DD, Hirzmann J, Pfister K.Blood samples were collected from 487 adult horses, including 83 pregnant mares, at a slaughterhouse located in Araguari, Minas Gerais State, Brazil. For each blood sample, the packed cell volume (PCV) was determined, and Giemsa-stained smears were microscopically examined for the presence of hemoparasites. The plasma was examined by the indirect fluorescent antibody test for detection of antibodies against Babesia caballi and Theileria equi. In addition, DNA was extracted and analyzed by a multiplex real-time polymerase chain reaction (PCR), specific for B. caballi and T. equi. Products of PC...
Quintana AM, Landolt GA, Annis KM, Hussey GS.Our understanding of innate immunity within the equine respiratory tract is limited despite growing evidence for its key role in both the immediate defense and the shaping of downstream adaptive immune responses to respiratory disease. As the first interface to undergo pathogen invasion, the respiratory epithelium is a key player in these early events and our goal was to examine the innate immune characteristics of equine respiratory epithelia and compare them to an in vitro equine respiratory epithelial cell model cultured at the air-fluid interface (AFI). Respiratory epithelial tissues, isol...
Tijms MA, Snijder EJ.Non-structural protein 1 (nsp1), the N-terminal subunit of the replicase polyprotein of the arterivirus Equine arteritis virus (EAV), is essential for viral subgenomic mRNA synthesis, but fully dispensable for genome replication. However, at the molecular level, the role of nsp1 in EAV subgenomic mRNA synthesis is poorly understood. A yeast two-hybrid screen did not reveal interactions between EAV nsp1 and other viral non-structural proteins or the nucleocapsid protein, although both nsp1 and the nucleocapsid protein were found to form homomers. Subsequently, a yeast two-hybrid screen of a HeL...
Li F, Puffer BA, Montelaro RC.Equine infectious anemia virus (EIAV) contains the simplest genome among lentiviruses in that it encodes only three putative regulatory genes (S1, S2, S3) in addition to the canonical gag, pol, and env genes, presumably reflecting its limited tropism to cells of monocyte/macrophage lineage. Tat and Rev functions have been assigned to S1 and S3, respectively, but the specific function for the S2 gene has yet to be determined. Thus, the function of S2 in virus replication in vitro was investigated by using an infectious molecular viral clone, EIAVUK. Various EIAVUK mutants lacking S2 were constr...
Hussey GS, Goehring LS, Lunn DP, Hussey SB, Huang T, Osterrieder N, Powell C, Hand J, Holz C, Slater J.Equine herpesvirus myeloencephalitis (EHM) remains one of the most devastating manifestations of equine herpesvirus type 1 (EHV-1) infection but our understanding of its pathogenesis remains rudimentary, partly because of a lack of adequate experimental models. EHV-1 infection of the ocular vasculature may offer an alternative model as EHV-1-induced chorioretinopathy appears to occur in a significant number of horses, and the pathogenesis of EHM and ocular EHV-1 may be similar. To investigate the potential of ocular EHV-1 as a model for EHM, and to determine the frequency of ocular EHV-1, our ...
Van de Walle GR, May ML, Sukhumavasi W, von Einem J, Osterrieder N.Glycoprotein G (gG) of alphaherpesviruses has been described to function as a viral chemokine-binding protein (vCKBP). More recently, mutant viruses devoid of gG have been shown to result in increased virulence, but it remained unclear whether the potential of gG to serve as a vCKBP is responsible for this observation. In this study, we used equine herpesvirus type 1 (EHV-1) as a model to study the pathophysiological importance of vCKBP activity. First, in vitro chemotaxis assays studying migration of immune cells, an important function of chemokines, were established. In such assays, supernat...
Schöniger S, Schoon HA.Mares are seasonally polyestric. The breeding season in spring and summer and the winter anestrus are flanked by transitional periods. Endometrial diseases are a frequent cause of subfertility and have an economic impact on the horse breeding industry. They include different forms of endometrosis, endometritis, glandular maldifferentiation, and angiosis. Except for suppurative endometritis, these are subclinical and can only be diagnosed by the microscopic examination of an endometrial biopsy. Endometrosis is characterized by periglandular fibrosis and nonsuppurative endometritis by stromal in...
