The study of diseases in horses encompasses a wide range of conditions affecting equine health, including infectious diseases, metabolic disorders, and genetic abnormalities. These diseases can impact various systems within the horse, such as respiratory, gastrointestinal, and musculoskeletal systems, and can lead to significant health challenges. Research in this area focuses on understanding the pathophysiology, diagnosis, prevention, and treatment of equine diseases. Common diseases studied include equine influenza, equine herpesvirus, and laminitis. This page provides access to peer-reviewed research studies and scholarly articles that explore the etiology, clinical presentation, and management strategies of diseases in horses, contributing to the advancement of equine veterinary medicine.
Harte T, Smith D, Moore J, Wells B.An article published in 1992 by Marion M. Pollin and I.R. Griffiths reviewed the topic of primary dysautonomias of the autonomic nervous system of unidentified origin in multiple domestic species, specifically cats, dogs and horses. Thirty-one years later, we appear no closer to identifying the causal agents of these strikingly similar diseases. This article reviews the similarities and differences in clinical presentation and pathology of dysautonomia in canids, felids, equids, leporids and other less frequently reported species.
Suvanto MT, Truong Nguyen PT, Vauhkonen H, Olander V, Joensuu R, Culverwell CL, Kaansalo K, Hepojoki J, Vapalahti O, Korhonen EM, Smura T, Huhtamo E.The genus (, ) comprises several globally important vector-borne animal viruses, such as borne bluetongue virus, African horse sickness virus and epizootic haemorrhagic disease virus (EHDV). Orbiviruses that are associated with mosquitoes are a diverse group including established mosquito-borne animal pathogens such as the Peruvian horse sickness virus and phylogenetically related less well-characterized viruses isolated mostly from mammals. Although reported from various geographic regions, these viruses have not previously been detected in northern Europe. Using next-generation sequencing a...
Gamage C, Holl W, Parreño V, Thieulent CJ, Balasuriya UBR, Vissani MA, Barrandeguy ME, Carossino M.Group A rotavirus (RVA) infections are a leading cause of neonatal diarrhoea in foals. Neonatal mice could serve as a useful tool to study the pathogenesis of equine RVA (ERVA) as well as a preclinical model for assessment of vaccine efficacy. This study aimed to comparatively evaluate the clinical, virological and pathological features of ERVA G3P[12] and G14P[12] infection in neonatal mice and compare them with porcine OSU G5P[7] and bovine UK G6P[5] RVA reference strains. Neonatal mice orally inoculated with equine, bovine and porcine RVA developed short-lived diarrhoea at variable rates, G...
Donovan K, Torres J, Zhu D, Herrington WG, Staplin N.Genome-wide association studies (GWAS) of disease progression are vulnerable to collider bias caused by selection of participants with disease at study entry. This bias introduces spurious associations between disease progression and genetic variants that are truly only associated with disease incidence. Methods of statistical adjustment to reduce this bias have been published, but rely on assumptions regarding the genetic correlation of disease incidence and disease progression which are likely to be violated in many human diseases. MR-Horse is a recently published Bayesian method to estimate...
Nikvand AA, Jalali SM, Bahrami S, Rahij Torfi H.Trypanosoma evansi (T. evansi) is a hemoprotozoan parasite affecting camels and equids, such as horses, mules, and donkeys, and is known to cause surra disease in these animals. Despite the worldwide distribution of T. evansi infections in equids, surra has not been reported in Arabian horses in Khuzestan Province for over 60 years. In September 2018, a 7-year-old Arabian mare was referred from a 10-horse farm in the suburbs of Ahvaz City. The mare presented with a history of weight loss, poor appetite, and proximity to a camel herd. Physical examination revealed a poor body condition score ...
Parra MT, Ayala MSF.A retrospective study was conducted at the Foal Care Equine Perinatology Center in Colombia from October 2017 to May 2023. The goal was to analyze the most frequent pathologies, as well as assess the sexes, ages, and breeds of the patients, with an emphasis on the perinatal population. Out of 945 clinical histories, 776 pertained to perinatology. Survival rates were calculated, and a descriptive analysis was performed. The overall survival rate for neonates was 73.6%, with females constituting 57% of the neonatal patients. The most prevalent breed among mares and neonates was the Creole Colomb...
Carvalho KS, de Barros CSL, Mendonça FS, Machado M, Riet-Correa F.In Brazil, CNS diseases in equids were little known until the 1980s. Since then, several diagnostic laboratories have been operating in different universities, initially in the South and Southeast regions and, later, in the Central-West, Northeast and North regions. However, the knowledge accumulated from the diagnoses of nervous system diseases of equids made at these institutions over the years has not been reviewed comprehensively, and many papers are published in Portuguese. Here, we review 18 diseases that occur in the nervous system of equids in Brazil, including some critical infectious...
Lab on a chipMay 28, 2025
Volume 25, Issue 11 2795-2796 doi: 10.1039/d5lc90048d
Heidenberger J, Reihs EI, Strauss J, Frauenlob M, Gültekin S, Gerner I, Toegel S, Ertl P, Windhager R, Jenner F, Rothbauer M.Correction for 'The effect of cyclic fluid perfusion on the proinflammatory tissue environment in osteoarthritis using equine joint-on-a-chip models' by Johannes Heidenberger et al., Lab Chip, 2025, 25, 2256-2269, https://doi.org/10.1039/d4lc01078g.
Death studiesMay 28, 2025
1-11 doi: 10.1080/07481187.2025.2510477
Kaufman SVA, Nieforth LO.For practitioners involved in equine-assisted services (EAS), the death of a horse can be a significant life disruption. This study aims to understand the communicative resilience processes that equine-assisted service practitioners express following the death of an equine in their program. This study analyzed secondary qualitative data from a cross-sectional online survey completed by 84 participants. Analysis revealed practitioners engaged in all five communicative resilience processes following the death of an equine in their program. This research extends current resilience research by exa...
Ochigbo GO, Ahn S, Belhumeur KA, Poissant J, Rosa BV.Unmanaged feral horses, naïve to dewormers, offer a unique opportunity to study natural communities of equine parasites. These communities may include parasites that are rare in managed populations, and these may be transmitted to domestic horses in areas where there is contact between feral and domestic equine populations. There have been only a few studies of gastrointestinal parasite populations in horses, and very few from North American equine populations. This study aimed to gain insights into parasite biology through identification of the strongyle parasite species infecting feral hors...
MacNeill AL, Micheloud JF, Parvin R, Gjessing M, Airas NA, Sant'Ana FJF, Adamek M.Zoonotic poxviruses, including monkeypox virus (MPV), the causative agent for Mpox disease, have gained significant media and scientific attention due to recent outbreaks in human populations across the globe. The increase in human cases of poxvirus infection is not unexpected, as routine vaccination against smallpox (a disease caused by the poxvirus variola virus, which cross protects against other orthopoxviruses) was discontinued in the 1980s after its eradication. Large numbers of vertebrate and invertebrate species are susceptible to infection by . Clinical signs and histologic lesions ca...
Silva VVD, Leite DPSBM, Gonçalves LMT, Pinto GOA, Oliveira PRF, Mota RA.Rabies is a lethal zoonosis caused by the rabies virus (RABV), primarily transmitted by the common vampire bat (Desmodus rotundus). Brazil, home to the largest equine population in South America, faces ongoing challenges with equine rabies, which impacts both the economy and public health. This study aimed to identify spatial and temporal patterns of rabies in equines in Brazil between 2006 and 2023. Data from the Zoosanitary Information System (SIZ) of the Brazilian Ministry of Agriculture, Livestock, and Food Supply (MAPA) were used. The incidence risk (IR) was calculated for each region and...
Firdausy LW, Fikri F, Wicaksono AP, Çalışkan H, Purnama MTE.Trypanosomiasis is a vector-borne parasitic disease with significant implications for animal health and rural livelihoods in Indonesia. Despite surveillance efforts, comprehensive national-level estimates of its prevalence in domesticated animals remain lacking. This study aimed to synthesize the pooled prevalence of trypanosomiasis across Indonesian provinces, identify contributing factors, and assess trends over time using a systematic review and meta-analysis. Unassigned: A systematic search was conducted in seven electronic databases (PubMed, Scopus, Web of Science, ScienceDirect, Cochrane...
Bordoni T, Dini FM, Morini M, Rinnovati R, Spadari A, Galuppi R.Mycetoma is a fungal chronic skin proliferative lesion rarely encountered in horses and often associated with fungi such as Scedosporium spp., Madurella spp., Phialophora spp., Curvularia spp., and less frequently with Aspergillus spp. A case of subcutaneous mycetoma in the cervical region in a 7-year-old male Quarter Horse, diagnosed through cytological, histological, cultural and molecular methods, is reported. Aspergillus nidulans, usually implicated in guttural pouch mycosis, was identified. This unusual case represents the second case report of mycetoma caused by Aspergillus nidulans in t...
Lin H, Deng D, Yan Z, Zou G, Shen Y.Staphylococcus aureus can transfer from animals to humans. Lichuan horse is an isolated breed living in a high-altitude area with limited use of antibiotics and is bred for use in tourism. To evaluate the risk of human-animal cross-transmission, the S. aureus was isolated from three horse farms in Lichuan, including healthy horses and horses with skin infections, farm workers and environment. From a collection of 111 samples, 18 S. aureus isolates were obtained. All the isolates were genome sequenced and their biological characteristics including antimicrobial susceptibility, virulence and bi...
Taylor K, Harrison A, Capaldo T.One of the most problematic situations for the estimated 60 million working donkeys and mules across the world is within the brick kiln environment. In countries such as Egypt, Nepal, India and Pakistan, donkeys and mules carry dried bricks into small kilns either by pulling carts or carrying loaded packs. The health and welfare problems of this environment are well documented: they may carry excessive loads; work long hours, have difficulties accessing food, water and rest options; and can frequently suffer untreated illnesses including dental problems, lameness and open wounds from poorly fi...
Mizuguchi Y, Niwa H, Inoue H, Iwano H.Hypoproteinaemia/hypoalbuminaemia is a typical clinical feature of Lawsonia intracellularis infection in horses, but amino acid perturbations in these horses have not been investigated. Objective: Clarifying blood amino acid levels in horses suffering from Lawsonia intracellularis infection to identify novel aspects of the disease. Methods: Retrospective observational study. Methods: A total of 135 serum samples collected from horses from 59 farms were used in this study. Horses diagnosed with the clinical form of equine proliferative enteropathy (EPE) were enrolled as a clinical group (n =...
Duaso J, Perez-Ecija A, Martínez E, Navarro A, De Las Heras A, Mendoza FJ.Equine piroplasmosis (EP) is a tick-borne disease affecting equids worldwide. Diagnosis is based on direct methods (blood smear or PCR) or indirect methods (serology); however, these techniques yield positive and negative results. Thus, an alternative, reliable, rapid, and cost-effective complementary tool, such as hematologic parameters and newly described hematologic ratios, could help in the EP diagnosis. This study describes the changes induced by piroplasmosis infection on hematologic parameters and ratios in horses. PCR-positive horses exhibited anemia and thrombocytopenia, whereas PCR...
Ballados-González GG, Cruz-Romero A, Martínez-Hernández JM, Aguilar-Domínguez M, Vieira RFC, Grostieta E, Becker I, Sánchez-Montes S.Hemotropic mycoplasmas (HM) are emerging pathogens known to infect a wide range of mammals, including ungulates like horses. These infections can lead to severe haematological conditions, posing a threat to animal health and welfare. Recent studies have begun shedding light on the prevalence and impact of HM on horse populations worldwide. For instance, in Germany, Iran, Nigeria, and Brazil, at least three species of HM have been identified in horses, with a lack in knowledge in Latin American countries like Mexico. Our research aims to fill a crucial knowledge gap regarding the presence of HM...
Elmahallawy EK, Hassan MF, Cano-Terriza D, Albalawi NO, Fajardo T, Gouda AA, Atiba A, Hendawy A, Villena I, Barakat AM, Alzaylaee H, Almería S....Toxoplasmosis, caused by the intracellular protozoan (), continues to be a widespread parasitic zoonotic disease globally. The seroepidemiology of infection in Egyptian equids, particularly donkeys, remains insufficiently explored. The present study was designed to assess the seroprevalence of in equines from Northern Egypt. Unassigned: A total of 360 serum samples from two equine species (157 horses and 203 donkeys) were obtained during 2023. The Modified Agglutination Test (MAT, cut-off of 1:25) was used to screen for the anti- antibodies. The study also analyzed potential risk factors th...
Liu J, Baumwart R, Kwon S.Ventriculophasic response (VR) in atrioventricular nodal (AVN) block is characterized by a shortening of the sinoatrial cycle length when a QRS complex is interposed between two P waves. This has been well documented in humans and dogs with AVN blocks but not in horses. Herein, we describe a horse with second-degree AVN blocks and constant PR intervals that exhibited 5:3 conduction and suspected VR at rest but less consistently after submaximal exercise. Proposed VR mechanisms include (1) inhibition of the Bezold-Jarisch reflex from reduced end-systolic volume during ventricular contraction; (...
Asti V, Summer A, Ablondi M, Sartori C, Giontella A, Pilastro V, Mecocci S, Cappelli K, Mancin E, Oian A, Mantovani R, Capomaccio S, Sabbioni A.Horses have undergone extensive natural and artificial selection, shaping the diversity of breeds observed today. Native Italian breeds present unique traits influenced by natural selection, such as adaptation to harsh climates, or hoof strength, but face challenges due to population declines and the reduction of their original breeding purpose. This study focuses on five local Italian breeds: Bardigiano, Haflinger, Maremmano, Murgese, and Italian Heavy Draught Horse, to understand how selection has shaped their populations. A total of 1620 individuals were genotyped with a medium-density SNP ...
Vitale V, Velloso Álvarez A, de la Cuesta-Torrado M, Neira-Egea P, Vandecandelaere M, Tee E, Gimeno M, van Galen G.In human medicine, neurological diseases have been associated with transient cardiac abnormalities. In horses, myocardial disease is rarely diagnosed and has been associated with a wide variety of causes. The aim of this article is to describe three horses with no previous cardiac disease, which all developed severe cardiomyopathy following neurological disease. A 5-year-old Shetland pony stallion was diagnosed with cardiomyopathy with arrhythmias following an episode of seizures caused by an accidental intra-arterial xylazine injection. A 20-year-old crossbred mare was hospitalised for an ope...
Connolly KM, Estell K.Dysphagia describes a clinical sign of pathologies of the oral cavity, pharynx, and oesophagus that carries potentially serious consequences for horses. Given the diversity of differential diagnoses that may cause dysphagia, an understanding of the prevalence of dysphagia in hospitalised patients, the distribution of aetiologies and clinical outcomes could inform diagnosis, treatment, and prognosis. Objective: This study aims to describe the incidence, signalment, history, aetiology, treatment, and outcome of horses presenting to a referral hospital for dysphagia. Methods: Retrospective case s...
Taylor WTT.Many of the most important equine health problems - and their solutions - relate to the role of horses as a domestic animal, especially in riding and other kinds of transport. Recently, new discoveries from the archaeological sciences have rewritten our understanding of early horse domestication, suggesting that the first ancestors of domestic horses emerged in the Black Sea Steppes of western Eurasia at the turn of the second millennium BCE. This new chronology places horse domestication within a wider trajectory of early animal transport, including cattle and donkey, across western Asia and ...
de Sousa ALV, de Sousa DER, de Macêdo IL, de Albuquerque Cerqueira L, da Fonseca YNG, Oliveira AB, das Chagas LVS, Gonçalves GB, Veado HC....This report describes the first documented case of intracerebral hemorrhage (ICH) in a horse following Bothrops snakebite envenomation. A 3-year-old mare developed acute kidney injury, systemic hemorrhage, and neurological signs before euthanasia. Postmortem findings confirmed massive ICH with intralesional venom identified by immunohistochemistry. Delayed treatment and insufficient antivenom likely contributed to the outcome. This case highlights the potential for cerebrovascular complications following Bothrops snakebite envenomation in horses, which may present as subtle neurological signs....
Toft K, Mardahl M, Hedberg-Alm Y, Anlén K, Tydén E, Nielsen MK, Honoré ML, Fromm B, Nielsen LN, Nejsum P, Thamsborg SM, Cirera S, Pihl TH.Non-strangulating intestinal infarctions (NSII) associated with Strongylus vulgaris infection and idiopathic peritonitis (IP) share similar clinical presentation but require different treatment approaches. Horses with NSII need surgical intervention, while idiopathic peritonitis cases can be successfully treated with antimicrobials. A correct diagnosis is thus crucial, but because the two diseases overlap in clinicopathological features, differentiation is difficult in clinical practice. MicroRNAs (miRNAs) are non-coding RNAs that exhibit measurable changes in abundance in tissues and circulat...
Hosseinzadeh S, Nofouzi K, Hasanzadeh F, Esmaeili S, Ayen E.Q fever is a frequently occurring illness that is induced by the bacterium ) that can infect humans and various animals. It targets the macrophage cells in the tissues, and circulating monocytes. Unassigned: This study was conducted between 2022 and 2023 in the West Azerbaijan and Ardabil provinces of northwestern Iran to examine the presence infection of . Specimens were obtained by swabbing from 140 mares (70 from each province) and 20 stallions (10 from each province) which were apparently healthy, and their DNA was analyzed using quantitative PCR assay detecting the element of the bacteri...
Hosseinzadeh S, Nofouzi K, Hasanzadeh F, Esmaeili S, Ayen E.Q fever is a frequently occurring illness that is induced by the bacterium ) that can infect humans and various animals. It targets the macrophage cells in the tissues, and circulating monocytes. Unassigned: This study was conducted between 2022 and 2023 in the West Azerbaijan and Ardabil provinces of northwestern Iran to examine the presence infection of . Specimens were obtained by swabbing from 140 mares (70 from each province) and 20 stallions (10 from each province) which were apparently healthy, and their DNA was analyzed using quantitative PCR assay detecting the element of the bacteri...
Morgan R, Keen J, McGowan C.Laminitis is one of the most common and frustrating clinical presentations in equine practice. While the principles of treatment for laminitis have not changed for several decades, there have been some important paradigm shifts in our understanding of laminitis. Most importantly, it is essential to consider laminitis as a clinical sign of disease and not as a disease in its own right. Once this shift in thinking has occurred, it is logical to then question what disease caused the laminitis. More than 90 per cent of horses presented with laminitis as their primary clinical sign will have develo...
Wang LF, Michalski WP, Yu M, Pritchard LI, Crameri G, Shiell B, Eaton BT.In 1994, a new member of the family Paramyxoviridae isolated from fatal cases of respiratory disease in horses and humans was shown to be distantly related to morbilliviruses and provisionally called equine morbillivirus (K. Murray et al., Science 268:94-97, 1995). To facilitate characterization and classification, the virus was purified, viral proteins were identified, and the P/V/C gene was cloned and sequenced. The coding strategy of the gene is similar to that of Sendai and measles viruses, members of the Paramyxovirus and Morbillivirus genera, respectively, in the subfamily Paramyxovirina...
Lyons S, Kapoor A, Schneider BS, Wolfe ND, Culshaw G, Corcoran B, Durham AE, Burden F, McGorum BC, Simmonds P.Non-primate hepacivirus (NPHV), equine pegivirus (EPgV) and Theiler's disease associated virus (TDAV) are newly discovered members of two genera in the Flaviviridae family, Hepacivirus and Pegivirus respectively, that include human hepatitis C virus (HCV) and human pegivirus (HPgV). To investigate their epidemiology, persistence and clinical features of infection, large cohorts of horses and other mammalian species were screened for NPHV, EPgV and TDAV viraemia and for past exposure through serological assays for NPHV and EPgV-specific antibodies. NPHV antibodies were detected in 43% of 328 ho...
Allsopp MT, Lewis BD, Penzhorn BL.The intra-erythrocytic parasite Theileria equi is one of two tick-transmitted causative agents of equine piroplasmosis. Piroplasms of T. equi can be transmitted across the equine placenta and once a horse is infected, it appears to remain a lifelong carrier, since anti-theilerial drugs suppress but do not eliminate the parasite. Carrier mares may transmit the organism to their offspring and this may result in abortion or neonatal piroplasmosis, but observations by some researchers suggest that foals may be born as carriers yet remain apparently healthy. Using a T. equi-specific oligonucleotide...
Smith KC, Blunden AS, Whitwell KE, Dunn KA, Wales AD.A detailed review of laboratory records for equine abortion is fundamental in establishing current disease trends and suggesting problems important for further research. Objective: To review the causes of abortion and neonatal death in equine diagnostic submissions to the Animal Health Trust over a 10 year period. Methods: The diagnoses in 1252 equine fetuses and neonatal foals were reviewed and analysed into categories. Results: Problems associated with the umbilical cord, comprising umbilical cord torsion and the long cord/cervical pole ischaemia disorder, were the most common diagnoses (38....
Bagcigil FA, Moodley A, Baptiste KE, Jensen VF, Guardabassi L.beta-Lactams and macrolides are important antibiotics for treatment of staphylococcal infections in both humans and animals. The aim of the study was to investigate the occurrence, species distribution and clonality of methicillin- and erythromycin-resistant staphylococci in the nasal cavity of dogs, horses, pigs, and cattle in Denmark. Nasal swabs were collected from a total of 400 animals, including 100 individuals of each species. Methicillin- and erythromycin-resistant staphylococci were isolated on selective media, identified by 16S rDNA sequencing, and typed by pulsed field gel electroph...
Knowles DP, Kappmeyer LS, Stiller D, Hennager SG, Perryman LE.Horses infected with Babesia equi were previously identified by the presence of antibodies reactive with a merozoite surface protein epitope (D. P. Knowles, Jr., L. E. Perryman, L. S. Kappmeyer, and S. G. Hennager. J. Clin. Microbiol. 29:2056-2058, 1991). The antibodies were detected in a competitive inhibition enzyme-linked immunosorbent assay (CI ELISA) by using monoclonal antibody 36/133.97, which defines a protein epitope on the merozoite surface. The gene encoding this B. equi merozoite epitope was cloned and expressed in Escherichia coli. The recombinant merozoite protein, designated equ...
Benavides JA, Salgado-Caxito M, Opazo-Capurro A, González Muñoz P, Piñeiro A, Otto Medina M, Rivas L, Munita J, Millán J.Antibiotic-resistant bacteria of critical importance for global health such as extended-spectrum beta-lactamases-producing (ESBL)- have been detected in livestock, dogs, and wildlife worldwide. However, the dynamics of ESBL- between these animals remains poorly understood, particularly in small-scale farms of low and middle-income countries where contact between species can be frequent. We compared the prevalence of fecal carriage of ESBL- among 332 livestock (207 cows, 15 pigs, 60 horses, 40 sheep, 6 goats, 4 chickens), 82 dogs, and wildlife including 131 European rabbits, 30 rodents, and 12 ...
Rushton JO, Lecollinet S, Hubálek Z, Svobodová P, Lussy H, Nowotny N.An unexpectedly high infection rate (26.1%) of tick-borne encephalitis virus (TBEV) was identified in a herd of 257 horses of the same breed distributed among 3 federal states in Austria. Young age (p<0.001) and male sex (p=0.001) were positively associated with infection.
Roy MF, Kwong GP, Lambert J, Massie S, Lockhart S.Despite its widespread use in equine medicine, the clinical value of the systemic inflammatory response syndrome (SIRS) concept in horses remains unknown. Objective: To study the prognostic value of measures of SIRS in horses and identify the best model of severe SIRS to predict outcome. Methods: A total of 479 consecutive adult horse emergency admissions to a private primary referral practice. Methods: Prospective observational study. All adult horses admitted for emergency treatment over the study period were included. Multivariate logistic regression and stepwise model selection were used. ...
Kono Y, Hirasawa K, Fukunaga Y, Taniguchi T.Horses which had passed a few months to a few years asymptomatically after the last recurrence of equine infectious anemia (EIA) showed a typical febrile response after treatment with the immunosuppressive agent, dexamethasone (DM) or cyclophosphamide (CY). In horses showing a febrile response, EIA virus which had not been neutralized by neutralizing antibody previously produced was propagated. In DM-treated horses it disappeared from the blood soon after pyretolysis and antibody against the virus was produced promptly. In contrast, detectable viremia persisted in CY-treated horses for 10 to 8...
Zhao Y, Li B, Bai D, Huang J, Shiraigo W, Yang L, Zhao Q, Ren X, Wu J, Bao W, Dugarjaviin M.The hindgut of horses is an anaerobic fermentative chamber for a complex and dynamic microbial population, which plays a critical role in health and energy requirements. Research on the gut microbiota of Mongolian horses has not been reported until now as far as we know. Mongolian horse is a major local breed in China. We performed high-throughput sequencing of the 16S rRNA genes V4 hypervariable regions from gut fecal material to characterize the gut microbiota of Mongolian horses and compare them to the microbiota in Thoroughbred horses. Fourteen Mongolian and 19 Thoroughbred horses were use...
Poissant J, Gavriliuc S, Bellaw J, Redman EM, Avramenko RW, Robinson D, Workentine ML, Shury TK, Jenkins EJ, McLoughlin PD, Nielsen MK, Gilleard JS.Horses are ubiquitously infected by a diversity of gastro-intestinal parasitic helminths. Of particular importance are nematodes of the family Strongylidae, which can significantly impact horse health and performance. However, knowledge about equine strongyles remains limited due to our inability to identify most species non-invasively using traditional morphological techniques. We developed a new internal transcribed spacer 2 (ITS2) DNA metabarcoding 'nemabiome' assay to characterise mixed strongyle infections in horses and assessed its performance by applying it to pools of infective larvae ...
Almazán C, Scimeca RC, Reichard MV, Mosqueda J.Babesia and Theileria are apicomplexan parasites that cause established and emerging diseases in humans, domestic and wild animals. These protozoans are transmitted by Ixodid ticks causing babesiosis or theileriosis, both characterized by fever, hemolytic anemia, jaundice, and splenomegaly. In North America (NA), the most common species affecting humans is B. microti, which is distributed in the Northeastern and Upper Midwestern United States (US), where the tick vector Ixodes scapularis is established. In livestock, B. bovis and B. bigemina are the most important pathogens causing bovine babe...
Tanaka T, Kasai H, Yamashita A, Okuyama-Dobashi K, Yasumoto J, Maekawa S, Enomoto N, Okamoto T, Matsuura Y, Morimatsu M, Manabe N, Ochiai K....Equine hepacivirus (EHcV) has been identified as a closely related homologue of hepatitis C virus (HCV) in the United States, the United Kingdom, and Germany, but not in Asian countries. In this study, we genetically and serologically screened 31 serum samples obtained from Japanese-born domestic horses for EHcV infection and subsequently identified 11 PCR-positive and 7 seropositive serum samples. We determined the full sequence of the EHcV genome, including the 3' untranslated region (UTR), which had previously not been completely revealed. The polyprotein of a Japanese EHcV strain showed ap...
Oue Y, Morita Y, Kondo T, Nemoto M.Equine coronavirus (ECoV) outbreaks have occurred three times at Obihiro Racecourse in Hokkaido, Japan. The third ECoV outbreak occurred between late February and early April 2012. The main clinical signs of affected horses were anorexia, pyrexia and leucopenia; gastrointestinal disease was observed in about 10% of affected horses. Two ECoV strains were isolated from diarrheal samples. All paired sera (9/9) collected from febrile horses showed seroconversion by neutralization test. Sequence and phylogenetic analysis of the ECoV isolated showed that putative amino acid sequences in S and N gene...
Di Gennaro A, Lorusso A, Casaccia C, Conte A, Monaco F, Savini G.A serum neutralization assay (SN) was compared with the official plaque reduction neutralization test for the quantitation of West Nile virus antibodies. A total of 1,348 samples from equid sera and 38 from human sera were tested by these two methods. Statistically significant differences were not observed, thus supporting the use of SN for routine purposes.
Ueti MW, Palmer GH, Kappmeyer LS, Statdfield M, Scoles GA, Knowles DP.The protozoan parasite Babesia equi replicates within erythrocytes. During the acute phase of infection, B. equi can reach high levels of parasitemia, resulting in a hemolytic crisis. Horses that recover from the acute phase of the disease remain chronically infected. Subsequent transmission is dependent upon the ability of vector ticks to acquire B. equi and, following development and replication, establishment of B. equi in the salivary glands. Although restriction of the movement of chronically infected horses with B. equi is based on the presumption that ticks can acquire and transmit the ...
Wittmann EJ, Baylis M.Changes in the distribution and abundance of insects are likely to be amongst the most important and immediate effects of climate change. We review here the risk that climate change poses to the UK's livestock industry via effects on Culicoides biting midges, the vectors of several arboviruses, including those that cause bluetongue (BT) and African horse sickness (AHS). The major old-world vector of BT and AHS viruses, C. imicola, occurs in southern Europe and will spread further north as global temperatures increase. It is unlikely, however, that in the foreseeable future it will reach and be...
Lönker NS, Fechner K, Wahed AAE.One Health (OH) is a crucial concept, where the interference between humans, animals and the environment matters. This review article focusses on the role of horses in maintaining the health of humans and the environment. Horses' impact on environmental health includes their influence on soil and the biodiversity of animal and plant species. Nevertheless, the effect of horses is not usually linear and several factors like plant-animal coevolutionary history, climate and animal density play significant roles. The long history of the relationship between horses and humans is shaped by the servic...
Lu G, Ou J, Ji J, Ren Z, Hu X, Wang C, Li S.Getah virus (GETV) is a mosquito-borne virus that was first determined in Malaysia in 1955, and can infect humans and multiple other mammals. GETV infection in horses has been reported in Japan and India, and causes great economic losses. In China, GETV has been identified in mosquitoes, pigs, foxes, and cattle with a wide geographical distribution, but has not been detected in horses. In August 2018, a sudden onset of fever was observed in racehorse in an equestrian training center in Guangdong Province in southern China. Blood samples were collected from the sick horse, and PCR/RT-PCR analys...
Johnson PJ.Certain management practices tend to promote the development of obesity (metabolic syndrome) in mature horses as they enter their teenage years. These management practices include the provision of starch-rich (high glycemic index) and fat-supplemented rations to healthy horses that are relatively inactive. Some horse breeds and ponies appear to be genetically predisposed to metabolic syndrome. The accretion of intra-abdominal adiposity by equids is associated with the development of insulin insensitivity (hyperinsulinemia), glucose intolerance, dyslipidemia, hypertension, and insidious-onset l...
Ross PF, Rice LG, Osweiler GD, Nelson PE, Richard JL, Wilson TM.During the 1989 corn harvest season, numerous reports of equine leukoencephalomalacia (ELEM) outbreaks and a pulmonary edema (PPE) syndrome in swine from several regions of the United States were received by the National Veterinary Services Laboratories (NVSL), Ames, Iowa. Previous and concurrent research linked Fusarium moniliforme and fumonisin-contaminated feeds to both diseases. Chemical and mycological investigations revealed fumonisin B1 (FB1) concentrations of 20 to 360 ppm in suspect swine feeds and 8 to 117 ppm in suspect equine feeds. Nonproblem feeds contained concentrations below 8...
Börjesson S, Greko C, Myrenås M, Landén A, Nilsson O, Pedersen K.The aim of this study was to investigate the occurrence of the newly described transferable colistin resistance gene mcr-9 in extended-spectrum β-lactamase (ESBL)-producing clinical Enterobacteriaceae isolates from horses in Sweden. A total of 56 whole-genome sequenced ESBL-producing Enterobacteriaceae isolates from horses were subjected to in silico detection of antimicrobial resistance genes and identification of plasmid replicons types. The colistin minimum inhibitory concentration (MIC) for mcr-positive isolates was determined by broth microdilution. Relatedness between Enterobacteriaceae...
Pusterla N, Kass PH, Mapes S, Johnson C, Barnett DC, Vaala W, Gutierrez C, McDaniel R, Whitehead B, Manning J.The prevalence and epidemiology of important viral (equine influenza virus [EIV], equine herpesvirus type 1 [EHV-1] and EHV-4) and bacterial (Streptococcus equi subspecies equi) respiratory pathogens shed by horses presented to equine veterinarians with upper respiratory tract signs and/or acute febrile neurological disease were studied. Veterinarians from throughout the USA were enrolled in a surveillance programme and were asked to collect blood and nasal secretions from equine cases with acute infectious upper respiratory tract disease and/or acute onset of neurological disease. A questionn...
Bell SA, Balasuriya UB, Gardner IA, Barry PA, Wilson WD, Ferraro GL, MacLachlan NJ.The objectives of this study were to estimate the prevalence of equine herpesviruses (EHV) 1-5 in the nasal secretions (NS) of a cohort of 12 mares and their foals from birth to 6 months of age, estimate the prevalence of EHV-1-5 infection of peripheral blood mononuclear cells (PBMC) of selected foals, and investigate phylogenetic relationships amongst the various strains of EHV-2 and 5. Virus-specific PCR assays were used to detect EHV-1-5 in NS and PBMC. A homologous portion of the glycoprotein B (gB) gene of the various strains of EHV-2 and 5 was sequenced and compared. EHV-2, 4, and 5 were...
Husso A, Jalanka J, Alipour MJ, Huhti P, Kareskoski M, Pessa-Morikawa T, Iivanainen A, Niku M.The establishment of the intestinal microbiota is critical for the digestive and immune systems. We studied the early development of the rectal microbiota in horse, a hindgut fermenter, from birth until 7 days of age, by qPCR and 16S rRNA gene amplicon sequencing. To evaluate initial sources of the foal microbiota, we characterised dam fecal, vaginal and oral microbiotas. We utilised an amplicon sequence variant (ASV) pipeline to maximise resolution and reproducibility. Stringent ASV filtering based on prevalence and abundance in samples and controls purged contaminants while preserving intest...
Doan R, Cohen ND, Sawyer J, Ghaffari N, Johnson CD, Dindot SV.The catalog of genetic variants in the horse genome originates from a few select animals, the majority originating from the Thoroughbred mare used for the equine genome sequencing project. The purpose of this study was to identify genetic variants, including single nucleotide polymorphisms (SNPs), insertion/deletion polymorphisms (INDELs), and copy number variants (CNVs) in the genome of an individual Quarter Horse mare sequenced by next-generation sequencing. Results: Using massively parallel paired-end sequencing, we generated 59.6 Gb of DNA sequence from a Quarter Horse mare resulting in an...
