Disease diagnosis in horses involves the identification and characterization of illnesses through various diagnostic methods and tools. This process is essential for effective veterinary care and management of equine health. Techniques used in diagnosing diseases in horses include clinical examinations, laboratory tests, imaging modalities such as ultrasonography and radiography, and molecular diagnostics. Blood tests are frequently utilized to assess parameters such as complete blood count and biochemical profiles, which can indicate underlying health issues. Additionally, advancements in genetic testing and biomarker identification have enhanced the ability to detect specific diseases early. This page aggregates peer-reviewed research studies and scholarly articles that explore diagnostic methodologies, their applications, and their impact on equine health management.
Iddagoda J, Gunasekara P, Handunnetti S, Jeewandara C, Karunatilake C, Malavige GN, de Silva R, Dasanayake D.It is clinically important to identify allergens in Artocarpus heterophyllus (jackfruit), Moringa oleifera (moringa), Trianthema portulacastrum (horse purslane) and Syzygium samarangense (rose apple). This study included 7 patients who developed anaphylaxis to jackfruit (1), moringa (2), horse purslane (3) and rose apple (1). We sought to determine allergens in the edible ripening stages of jackfruit (tender, mature, and ripened jackfruit) and seeds, edible parts of moringa (seeds, seedpod, flesh inside seedpod, and leaves), horse purslane leaves and ripened rose apple fruit. The persistence o...
Uchida-Fujii E, Niwa H, Senoh M, Kato H, Kinoshita Y, Mita H, Ueno T.We encountered 34 Clostridioides difficile (C. difficile) infection (CDI) cases among Thoroughbred horses in Japan from 2010 to 2021. Among them, 79.4% (27/34) either died or were euthanised. The risk factors associated with CDI and mortality among Japanese Thoroughbred horses remain unclear. We used genetic methods to examine C. difficile strains and their relationships with prognosis. Twenty-two (64.7%) cases were hospitalised at the onset of colitis. Outcomes were balanced for hospitalisation rates at the onset of colitis. The mortality rates of cases treated with metronidazole (65.0%) were...
Bishop RC, Kemper AM, Burges JW, Jandrey KE, Wilkins PA.To evaluate a point-of-care viscoelastic coagulation monitor (VCM Vet) for use in horses by assessing variability between devices and establish reference intervals (RIs) for healthy adult horses. Methods: Prospective observational study. Methods: Two university teaching hospitals. Methods: Healthy adult horses (n = 68). Methods: None. Results: Blood collected by direct jugular venipuncture was applied directly from the syringe into 2 VCM Vet cassettes to establish coefficients of variation (CVs) and RIs for reported parameters of clotting time (CT), clot formation time (CFT), alpha angle, am...
Calixto-Vega LC, Martínez-Aranzales JR.The existing literature does not contain information about the prevalence of gastric ulcers in mules, and on the potential associations between the presence of ulcers and work load, work type, diet, sex, age and body condition score (BCS). Objective: To estimate the prevalence and factors associated with mule gastric ulcer syndrome (MGUS) and evaluate its distribution in both mule squamous gastric disease (MSGD) and mule glandular gastric disease (MGGD) mucosa in a population of mules in Colombia. Methods: Observational, cross-sectional. Methods: A total of 97 clinically healthy mules of diffe...
Bennet ED, Parkin TDH.Racehorse training and racing schedules in many parts of the United States and Canada were interrupted or otherwise reduced during the first three to six months of 2020. This was an indirect consequence of mitigations to prevent the spread of the pandemic virus COVID-19. Data from the Equine Injury Database, a census-level survey of all race starts made in the USA and Canada, were used to analyse the incidence of fatalities in 2009-2022 among three age cohorts of racehorses within each year. There was a statistically significant increase in the incidence of musculoskeletal fatalities among 2-y...
Levasseur A, Arsenault J, Paré J.West Nile virus (WNV) became notifiable in horses in 2003 in Canada and has been reported every year since. The objective of this study was to describe the spatiotemporal distribution of WNV in horses between 2003 and 2020 in Canada. Methods: The 848 symptomatic and laboratory-confirmed WNV cases in horses reported to the Canadian Food Inspection Agency between 2003 and 2020. Methods: Canada was divided into eastern and western regions for analysis. For each case, location and date of notification were captured. Triennial maps were made to describe the spatiotemporal distribution and expansion...
Górski K, Borowska M, Turek B, Pawlikowski M, Jankowski K, Bereznowski A, Polkowska I, Domino M.Equine Odontoclastic Tooth Resorption and Hypercementosis (EOTRH) syndrome is a dental disease where the radiographic signs may be quantified using radiographic texture features. This study aimed to implement the scaled-pixel-counting protocol to quantify and compare the image structure of teeth and the density standard in order to improve the identification of the radiographic signs of tooth resorption and hypercementosis using the EOTRH syndrome model. Results: A detailed examination of the oral cavity was performed in 80 horses and maxillary incisor teeth were evaluated radiographically, in...
Loubière C, Moreau P, Marine R, Hélie P, Jean D.The objectives of this study were to quantify lymphocytes and eosinophils in the mucosa of the duodenum and rectum in asthmatic horses. Asthmatic horses were evaluated in a symptomatic (after 6 weeks of exposure to moldy hay) and asymptomatic status (3 and 7 months after being fed alfalfa pellets [n = 4] or treated with inhaled fluticasone [6]). Duodenal and rectal biopsies were endoscopically (n = 4 to 6) taken in each horse. Eosinophils were counted on slides stained with hematoxylin, eosin, phloxine, and saffron, and immunohistochemistry was used to evaluate T and B lymphocytes using CD3 an...
Enriquez CK, Morrow JK, Graves A, Johnson A.Equine protozoal myeloencephalitis (EPM) caused by Sarcocystis neurona remains an antemortem diagnostic challenge in some horses. Recent work suggested the use of real-time PCR (rtPCR) on cerebrospinal fluid (CSF) as a promising diagnostic tool. Objective: To evaluate the sensitivity and specificity of S. neurona rtPCR on CSF for EPM diagnosis using horses with EPM and S. neurona-seropositive horses with other neurologic conditions. Methods: Ninety-nine horses with neurologic disease that underwent complete neurologic examination, CSF collection, and, if euthanized, necropsy including the cent...
Laus F, Gialletti R, Bazzano M, Laghi L, Dini F, Marchegiani A.Osteoarthritis (OA) is a common cause of lameness in sport horses with a significant economic impact. The prevention of OA is crucial since no effective treatment is available. This study aimed to apply untargeted metabolomic analysis to investigate the differences in synovial fluid (SF) composition between healthy and OA-affected joints in horses. SF collected from healthy (n.8) and OA (n.11) horses was analyzed using H-NMR analysis. Metabolomic analysis allowed 55 different metabolites to be identified and quantified in SF samples. Nineteen metabolites were found to be differently concentrat...
Cox A, Stewart AJ.Insect Bite Hypersensitivity (IBH, Queensland itch, sweet itch, equine summer eczema) is the most common pruritic disease of horses. It is most often caused by sensitivity to the saliva of spp. of biting midges; however, it can also be caused by hypersensitivity to other insect species. The prevalence of IBH in horses is reported to be as high as 60% in some parts of the world. Due to the severe pruritus and effects of secondary self-trauma, IBH has animal welfare concerns, and there is currently no cure. Management of this condition is life-long, time consuming and costly. New grading system...
Bertin FR, Frank N, Breuhaus BA, Schott HC, Kritchevsky JE.Equine thyroid disorders pose a diagnostic challenge in clinical practice because of the effects of nonthyroidal factors on the hypothalamic-pituitary-thyroid axis, and the horse's ability to tolerate wide fluctuations in thyroid hormone concentrations and survive without a thyroid gland. While benign thyroid tumours are common in older horses, other disorders like primary hypothyroidism or hyperthyroidism in adult horses and congenital hypothyroidism in foals are rare. There is a common misunderstanding regarding hypothyroidism in adult horses, especially when associated with the clinical pro...
Hoblick S, Denagamage TN, Morton AJ, McCarrel TM.Post-anaesthetic fever is a known complication of general anaesthesia, however, its incidence in horses undergoing elective magnetic resonance imaging (MRI) is unknown. Objective: To determine the incidence of post-anaesthetic fever in horses undergoing elective orthopaedic MRI and determine whether prophylactic antimicrobial therapy would be associated with a reduction in the incidence of post-anaesthetic fever. We hypothesised that prophylactic antimicrobials would be associated with a reduction in the incidence of post-anaesthetic fever. Methods: Retrospective cross-sectional study. Methods...
Clark BL, Stewart AJ, Kemp KL, Bamford NJ, Bertin FR.Field tests and their association with laminitis have not been evaluated in large cohorts. The objectives of this study were to evaluate the performance of basal insulin (BI), the oral sugar test (OST) and the insulin tolerance test (ITT) to diagnose ID and investigate their association with laminitis. Insulin dysregulation status was determined in 146 ponies using BI (insulin concentration >20 µIU/mL), an OST (insulin concentration >65 µIU/mL at 60 or 90min after oral administration of 0.45mL/kg corn syrup) and an ITT (< 50% reduction in glucose concentration 30min after intravenous adminis...
Latham E, Scherrer NM, Stefanovski D.To compare the measurement of intraocular pressure in horses with clinical ocular disease using three tonometry devices. Conclusions: All three tonometers showed strong agreement, however, the TonoVet and the TonoVet Plus carried the strongest agreement with the TonoVet Plus having slightly higher measurements overall compared with the TonoVet. Due to small variations between devices, it is recommended that the same device be used for serial measurements of intraocular pressure. However, all three devices are appropriate to use in horses presented for ophthalmic evaluation.
Frippiat T, Art T, Tosi I.Airway hyperresponsiveness (AHR) and inflammation are both observed in human and equine asthma. The aim of this study was to assess the timeline and relationship of both features at the subclinical onset of severe equine asthma (SEA). First, the repeatability of the pulmonary function test (PFT) using impulse oscillometry system, and the methacholine bronchoprovocation test (BPT) were assessed at a 1-day interval on six SEA horses in clinical remission and six control horses. Then, clinical and ancillary tests were performed before and after a 1-week low-dust environmental challenge, including...
Hepworth-Warren KL, Estell K, Cowles B, Amodie D, Crisman M.Serum amyloid A (SAA) is a major acute phase protein in horses which could be a useful tool for assessing clinical response to treatment of bacterial pneumonia in adult horses.
Jondeau C, Guyonnet A, Losada A, Laloy E, Reyes-Gomez E, Le Dudal M, Chahory S.To describe a case of lipogranulomatous conjunctivitis in a horse. Methods: A client-owned 12-year-old Standardbred gelding presenting with chronic conjunctivitis and palpebral masses. Methods: Complete ophthalmic examination, surgical excision, histopathology, and bacterial culture of biopsy samples were performed. Results: Upper and lower eyelids of both eyes were affected, with multiple yellow-to-white nodules on the palpebral conjunctiva, adjacent to the eyelid margin. Nodule removal was achieved via partial tarsal plate excision. Histopathological examination revealed granulomatous inflam...
Amory H, Cesarini C, De Maré L, Loublier C, Moula N, Detilleux J, Saulmont M, Garigliany MM, Lecoq L.The objective of this retrospective study was to evaluate the clinical significance of fecal quantitative real-time polymerase chain reaction (qPCR) results when taking the cycle threshold values (Ct) into account. The study included 120 qPCR-positive fecal samples obtained from 88 hospitalized horses over a 2-year period. The mean Ct of the qPCR test was evaluated in regard to (1) clinical outcome and (2) systemic inflammatory response syndrome (SIRS) status (no SIRS, moderate SIRS, or severe SIRS) of the sampled horses. An ROC analysis was performed to establish the optimal cut-off Ct valu...
Rule EK, Boyle AG, Stefanovski D, Anis E, Linton J, Lorello O.Equine granulocytic anaplasmosis (EGA) is a common disease in adult horses, but clinical disease in foals is rarely reported. The relationship between equine maternal and neonatal antibodies to Anaplasma phagocytophilum is unclear. Objective: That mares in an endemic region would be seropositive for A. phagocytophilum and that mare and foal serum IgG concentrations for A. phagocytophilum would correlate. Additionally, we hypothesized that foal IgG concentrations for A. phagocytophilum acquired by passive immunity would decline by 6 months of age. Methods: Twenty-two healthy mare-foal pairs. ...
El-Hage C, Legione A, Devlin J, Hughes K, Jenkins C, Gilkerson J. is an important zoonotic pathogen. Although primarily a pathogen of birds, from which infection can spillover into humans and other mammalian hosts, the importance of as a cause of equine reproductive loss and the risk of infection to humans in contact with infected horses are increasingly being recognised in Australia and elsewhere. Despite the risks to both human and equine health, infection in horses is incompletely understood. This study aimed to update and summarise cases of equine psittacosis in Australia in the period 2018-2022, thus addressing a knowledge gap relating to recent case...
Stefaniuk-Szmukier M, Piórkowska K, Ropka-Molik K.Equine metabolic syndrome (EMS) has become an important issue in modern veterinary medicine and is linked to the common, extremely painful, most-of-the-time performance-terminating hoof laminitis. The growing knowledge in the field of genetic background, inducing environmental factors, diagnosis, treatment and maintenance of affected equines led us to summarise the available information to be used not only for scientific purposes but for fieldwork. In horses, the clinical presentation of EMS includes: obesity or local fat deposition, bilateral lameness or hoof rings attributed to ongoing or pr...
Okolo CC, Emejuo NT, Udeagbala NG, Emeto UE, Ezema AS, Omeje OV, Nweze NE.Sample processing methods and storage time affect the outcome of biochemical analysis. Objectives: We aimed to assess the effects of dipotassium-ethylenediaminetetraacetic acid (K2-EDTA) and lithium-heparin treatments and storage times on selected analytes in equine synovial fluid (SF). Conclusions: The analytes-except for TP-became unstable within a few hours postcollection. Lithium-heparin and K2-EDTA treatments significantly altered ALP, LDH, TNCCs, and pH but not the TP concentrations of equine SF. Studies establishing reference intervals for these analytes based on the anticoagulant used ...
Cassady KR, Minter LJ, Gruber EJ.Field veterinarians and researchers studying wild species, such as the southern white rhinoceros, often work in remote areas with limited access to standard laboratory equipment, hindering the ability to measure serum analytes.
Objectives: The first objective was to produce an inexpensive, manually operated centrifuge that could accept standard laboratory tubes by modifying a consumer-grade salad spinner with low-cost materials. The second objective was to compare biochemistry analysis results obtained from equine and southern white rhinoceros serum separated by traditional laboratory and m...
Sander J, Terhardt M, Janzen N, Renaud B, Kruse CJ, François AC, Wouters CP, Boemer F, Votion DM.Equine atypical myopathy is caused by hypoglycin A (HGA) and methylenecyclopropylglycine (MCPrG), the known protoxins of sycamore maple (Acer pseudoplatanus). Various tissues from five atypical myopathy cases were analyzed but only HGA was found. Whether deamination of MCPrG has already occurred in the intestine as the first stage of metabolization has not been investigated. Activation of the protoxins to methylenecyclopropylacetyl (MCPA)-CoA and methylenecyclopropylformyl (MCPF)-CoA, respectively, occurred mainly in the skeletal muscles, as evidenced by very high concentrations of MCPA-carnit...
Marshall-Gibson ME, Durham MG, Seabaugh KA, Moorman VJ, Ferris DJ.Back pain is a common complaint, clinical finding and performance limiting factor in sport horses. This study sought to gather current veterinary trends in the diagnosis, treatment and management of primary equine back pain in the United States. A 22 question survey was distributed electronically to equine practitioners through AAEP and ACVSMR listservs and through closed social media groups. The survey was open from April 20, 2022 to July 5, 2022. Responses were analyzed using Microsoft excel pivot tables. Ninety-seven survey responses were obtained and analyzed. Respondents reported the clin...
Carossino M, Balasuriya UBR, Thieulent CJ, Barrandeguy ME, Vissani MA, Parreño V.Equine rotavirus A (ERVA) is the leading cause of diarrhea in foals, with G3P[12] and G14P[12] genotypes being the most prevalent. Recently, equine G3-like RVA was recognized as an emerging infection in children, and a group B equine rotavirus (ERVB) was identified as an emergent cause of foal diarrhea in the US. Thus, there is a need to adapt molecular diagnostic tools for improved detection and surveillance to identify emerging strains, understand their molecular epidemiology, and inform future vaccine development. We developed a quadruplex TaqMan RT-qPCR assay for differentiation of ERVA an...
Matas Riera M, Cardenas Nadal M, Martínez-Sogues L, Ferrer L.Dermatological clinical signs have been seldom reported in the literature secondary to equine leishmaniasis. This case depicts the clinical signs, treatment, and outcome of a young horse with a pink, elevated lesion on the ventromedial quadrant of the cornea. A corneal cytology was performed and revealed the presence of leishmania amastigotes reaching the diagnosis of keratitis secondary to leishmania. Surgical resection was recommended but the owner declined the procedure, and the lesion was treated with a topical antimonial for 6 weeks. The lesion reduced remarkably during the first weeks ...
Gustafson AL, Tallmadge RL, Ramlachan N, Miller D, Bird H, Antczak DF, Raudsepp T, Chowdhary BP, Skow LC.A physical map of ordered bacterial artificial chromosome (BAC) clones was constructed to determine the genetic organization of the horse major histocompatibility complex. Human, cattle, pig, mouse, and rat MHC gene sequences were compared to identify highly conserved regions which served as source templates for the design of overgo primers. Thirty-five overgo probes were designed from 24 genes and used for hybridization screening of the equine USDA CHORI 241 BAC library. Two hundred thirty-eight BAC clones were assembled into two contigs spanning the horse MHC region. The first contig contain...
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), ...
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...
Dorn PL, Derse D.Deletion analysis of the equine infectious anemia virus long terminal repeat revealed that sequences responsive to virus-specific transactivation are located within the region spanning the transcriptional start site (-31 to +22). In addition, an active exon of a trans-acting factor (tat) was identified downstream of pol and overlapping env (nucleotides 5264 to 5461). Activation by tat is accompanied by an increase in the steady-state levels of mRNA directed by the equine infectious anemia virus long terminal repeat.
Marasas WF.Fusarium moniliforme is one of the predominant fungi associated with corn intended for human and animal consumption world-wide. Fumonisins, food-borne carcinogens that occur naturally in corn, were first isolated and chemically characterized in South Africa in 1988. The major metabolite, fumonisin B1 (FB1), was subsequently shown to cause leukoencephalomalacia (LEM) in horses, pulmonary edema syndrome (PES) in pigs, and liver cancer in rats. FB1 is also a cancer promoter and initiator in rat liver; hepatotoxic to horses, pigs, rats, and vervet monkeys; cytotoxic to mammalian cell cultures; and...
Wieringa R, de Vries AA, Rottier PJ.Equine arteritis virus (EAV) is an enveloped, positive-stranded RNA virus belonging to the family Arteriviridae of the order NIDOVIRALES: Six transmembrane proteins have been identified in EAV particles: the nonglycosylated membrane protein M and the glycoprotein GP(5) (previously named G(L)), which occur as disulfide-bonded heterodimers and are the major viral envelope proteins; the unglycosylated small envelope protein E; and the minor glycoproteins GP(2b) (formerly designated G(S)), GP(3), and GP(4). Analysis of the appearance of the GP(2b), GP(3), and GP(4) proteins in viral particles by g...
Bowles DE, Holden VR, Zhao Y, O'Callaghan DJ.To assess the role of the equine herpesvirus type 1 (EHV-1) ICP0 protein (EICP0) in gene regulation, a variety of molecular studies on the EICP0 gene and gene products of both the attenuated cell culture-adapted Kentucky A (KyA) strain and the Ab4p strain were conducted. These investigations revealed that (i) the ICP0 open reading frame (ORF) of the KyA virus strain is 1,257 bp in size and would encode a protein of 419 amino acids, and in comparison to the ICP0 gene (ORF63) of the Ab4p strain of 1,596 bp (E. A. Telford, M. S. Watson, K. McBride, and A. J. Davison, Virology 189:304-316, 1992), ...
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...
Zhao S, McDermott PF, White DG, Qaiyumi S, Friedman SL, Abbott JW, Glenn A, Ayers SL, Post KW, Fales WH, Wilson RB, Reggiardo C, Walker RD.Three hundred and eighty Salmonella isolates recovered from animal diagnostic samples obtained from four state veterinary diagnostic laboratories (AZ, NC, MO, and TN) between 2002 and 2003 were tested for antimicrobial susceptibilities and further characterized for bla(CMY) beta-lactamase genes, class 1 integrons and genetic relatedness using PFGE. Forty-seven serovars were identified, the most common being S. Typhimurium (26%), S. Heidelberg (9%), S, Dublin (8%), S. Newport (8%), S. Derby (7%), and S. Choleraesuis (7%). Three hundred and thirteen (82%) isolates were resistant to at least one ...
Knox J, Cowan RU, Doyle JS, Ligtermoet MK, Archer JS, Burrow JN, Tong SY, Currie BJ, Mackenzie JS, Smith DW, Catton M, Moran RJ, Aboltins CA....Murray Valley encephalitis virus (MVEV) is a mosquito-borne virus that is found across Australia, Papua New Guinea and Irian Jaya. MVEV is endemic to northern Australia and causes occasional outbreaks across south-eastern Australia. 2011 saw a dramatic increase in MVEV activity in endemic regions and the re-emergence of MVEV in south-eastern Australia. This followed significant regional flooding and increased numbers of the main mosquito vector, Culex annulirostris, and was evident from the widespread seroconversion of sentinel chickens, fatalities among horses and several cases in humans, res...
Blackmore TM, Dugdale A, Argo CM, Curtis G, Pinloche E, Harris PA, Worgan HJ, Girdwood SE, Dougal K, Newbold CJ, McEwan NR.The horse, as a hindgut fermenter, is reliant on its intestinal bacterial population for efficient diet utilisation. However, sudden disturbance of this population can result in severe colic or laminitis, both of which may require euthanasia. This study therefore aimed to determine the temporal stability of the bacterial population of faecal samples from six ponies maintained on a formulated high fibre diet. Bacterial 16S rRNA terminal restriction fragment length polymorphism (TRFLP) analyses of 10 faecal samples collected from 6 ponies at regular intervals over 72 hour trial periods identifie...
Bryant NA, Wilkie GS, Russell CA, Compston L, Grafham D, Clissold L, McLay K, Medcalf L, Newton R, Davison AJ, Elton DM.Equine herpesvirus 1 (EHV-1) causes respiratory disease, abortion, neonatal death and neurological disease in equines and is endemic in most countries. The viral factors that influence EHV-1 disease severity are poorly understood, and this has hampered vaccine development. However, the N752D substitution in the viral DNA polymerase catalytic subunit has been shown statistically to be associated with neurological disease. This has given rise to the term "neuropathic strain," even though strains lacking the polymorphism have been recovered from cases of neurological disease. To broaden understan...
Science (New York, N.Y.)October 30, 1981
Volume 214, Issue 4520 562-564 doi: 10.1126/science.6270790
Studdert MJ, Simpson T, Roizman B.Viruses classified by immunologic criteria as equine herpesvirus 1 cause respiratory disease and abortion in horses. Restriction endonuclease analyses of the DNA's of viruses from animals with respiratory disease and from aborted fetuses show that the patterns for respiratory viruses, while similar to each other, are entirely different from the patterns for fetal viruses. It is therefore proposed that the DNA restriction endonuclease patterns of fetal and respiratory viruses analyzed in this study be designated as prototypic of equine herpesvirus 1 and 4, respectively.
Bashiruddin JB, Cammà C, Rebêlo E.Babesia equi and Babesia caballi are tick-borne haemoparasites that may cause babesiosis of Equidae. In southern Europe B. equi is enzootic and infections may occur asymptomatically and more frequently than those due to B. caballi. Complement fixation test (CFT) is the official serological test for the diagnosis of equine babesiosis, but it has low sensitivity during early and latent stages of the disease. With the aim of developing more sensitive and rapid direct diagnostic alternatives, PCR systems that amplified DNA targets of 664 or 659 bp regions of the 16S rRNA genes were designed and de...
Meier AD, de Laat MA, Reiche DB, Pollitt CC, Walsh DM, McGree JM, Sillence MN.The aim of this study was to investigate the relationship between laminitis development in ponies and insulin/glucose concentrations in response to the oral glucose test (OGT) and a dietary challenge high in nonstructural carbohydrates (NSCs). After undergoing an OGT (1 g dextrose/kg BW in feed), 37 ponies with 2-h serum insulin concentrations ranging from 22 to 1,133 μIU/mL were subjected to a diet challenge period (DCP), consuming 12 g NSC/kg BW/d for up to 18 d. Insulin and glucose responses were measured on day 2 of the DCP. Clinical laminitis was diagnosed by blinded experts and confi...
van Niekerk S, Human S, Williams J, van Wilpe E, Pretorius M, Swanepoel R, Venter M.Old World alphaviruses were identified in 52 of 623 horses with febrile or neurologic disease in South Africa. Five of 8 Sindbis virus infections were mild; 2 of 3 fatal cases involved co-infections. Of 44 Middelburg virus infections, 28 caused neurologic disease; 12 were fatal. Middelburg virus likely has zoonotic potential.
Field H, Crameri G, Kung NY, Wang LF.Hendra virus, a novel and fatally zoonotic member of the family Paramyxoviridae, was first described in Australia in 1994. Periodic spillover from its natural host (fruit bats) results in catastrophic disease in horses and occasionally the subsequent infection of humans. Prior to 2011, 14 equine incidents involving seven human cases (four fatal) were recorded. The year 2011 saw a dramatic departure from the sporadic incidents of the previous 16 years, with a cluster of 18 incidents in a single 3-month period. The fundamental difference in 2011 was the total number of incidents, the geographic ...
Herteman N, Vargas A, Lavoie JP.Low-density neutrophils (LDNs) are a subset of neutrophils first described in the bloodstream upon pathological conditions, and recently, in the blood of healthy humans. LDNs may have an enhanced pro-inflammatory (low-density granulocytes, LDGs) or an immunosuppressive (Granulocytic myeloid-derived suppressor cells, G-MDSCs) profile. Whether these characteristics are specific to LDNs or related to disease states is unknown. Thus, we sought to investigate the properties of LDNs in both health and disease states, and to compare them to those of autologous normal-density neutrophils (NDNs). We st...
Wong DM, Ruby RE, Dembek KA, Barr BS, Reuss SM, Magdesian KG, Olsen E, Burns T, Slovis NM, Wilkins PA.The original equine sepsis score provided a method of identifying foals with sepsis. New variables associated with sepsis have been evaluated, but the sepsis score has not been updated. Objective: To evaluate the sensitivity and specificity of 2 updated sepsis scores and the systemic inflammatory response syndrome (SIRS) criteria in regard to detecting sepsis in foals. Methods: Two-hundred and seventy-three ill foals and 25 healthy control foals. Methods: Historical, physical examination, and clinicopathologic findings were used to calculate the original sepsis score and 2 updated sepsis score...
Miszczak F, Tesson V, Kin N, Dina J, Balasuriya UB, Pronost S, Vabret A.Equine coronavirus (ECoV) is involved mainly in enteric infections. Following the recent description of ECoV in 2000, this study reports for the first time the presence of ECoV in France and, on a wider scale, in Europe. ECoV was molecularly detected from diarrheic and respiratory specimens. Sequencing and phylogenetic analyses demonstrated that European strains are most closely related to the reference North American strain (ECoV-NC99) than the Asian strain (ECoV-Tokachi09).
Fenger CK, Granstrom DE, Langemeier JL, Stamper S, Donahue JM, Patterson JS, Gajadhar AA, Marteniuk JV, Xiaomin Z, Dubey JP.Sarcocystis neurona is an apicomplexan that causes equine protozoal myeloencephalitis (EPM) in North and South America. Horses appear to be an aberrant host, because the merozoites continually divide in the central nervous system, without encysting. The natural host species has not previously been identified. The small subunit ribosomal RNA (SSURNA) gene of S. neurona was compared to those of Sarcocystis muris, Sarcocystis cruzi, Toxoplasma gondii, and Cryptosporidium parvum to identify a unique region suitable for a species-specific amplification primer. The S. neurona SSURNA primer was used ...
Harlow BE, Lawrence LM, Flythe MD.Antibiotics are important to equine medicine, but antibiotic-associated diarrhea (AAD) can lead to poor performance and even mortality. AAD is attributed to disruption of the hindgut microbiota, which permits proliferation of pathogenic microbes. The goal of this study was to evaluate the effects of common antibiotics on cellulolytic bacteria, lactobacilli, and AAD-associated pathogens in the feces of healthy horses. Fifteen horses were assigned to three treatment groups (blocked by age and sex): control (no antibiotics), trimethoprim-sulfadiazine (PO), or ceftiofur (IM). Fecal samples (n=8 pe...
Smith KL, Allen GP, Branscum AJ, Frank Cook R, Vickers ML, Timoney PJ, Balasuriya UB.A panel of 426 archived EHV-1 isolates collected (1951-2006) from equine abortions was analyzed using a real-time Taq-Man((R)) allelic discrimination PCR assay. Based on previous findings, isolates possessing adenine at nucleotide position 2254 (A(2254)) in ORF30 were classified as having a non-neuropathogenic genotype and those with guanine at 2254 (G(2254)) were designated as the neuropathogenic genotype. The resultant data demonstrated that viruses with the neuropathogenic genotype existed in the 1950s and isolates with this genotype increased from 3.3% in the 1960s to 14.4% in the 1990s. T...
Barlough JE, Madigan JE, DeRock E, Dumler JS, Bakken JS.A Thoroughbred filly that developed clinical signs of equine granulocytic ehrlichiosis following inoculation with the human granulocytotropic ehrlichia was shown to be resistant to challenge with Ehrlichia equi, a closely related agent. This result further substantiates the close and potentially conspecific relationship between these two granulocytotropic ehrlichiae.
Verma A, Artiushin S, Matsunaga J, Haake DA, Timoney JF.Recurrent uveitis as a sequela to Leptospira infection is the most common infectious cause of blindness and impaired vision of horses worldwide. Leptospiral proteins expressed during prolonged survival in the eyes of horses with lesions of chronic uveitis were identified by screening a phage library of Leptospira interrogans DNA fragments with eye fluids from uveitic horses. Inserts of reactive phages encoded several known leptospiral proteins and two novel putative lipoproteins, LruA and LruB. LruA was intrinsically labeled during incubation of L. interrogans in medium containing [14C]palmiti...
Li B, Wang H, Liang G.Getah virus (GETV) is a zoonotic virus transmitted by mosquitoes, belonging to the family, genus. It was first isolated from mosquitoes in Malaysia in 1955, being widespread in island countries in the South Pacific region. Since the beginning of the 21st century, GETV expanded its range and geographical distribution from low-latitude tropical regions to 60° north latitude, being isolated from 17 different species of mosquitoes belonging to five genera of Culicidae (, , , and ), as well as from midges in Eurasia. Molecular genetic evolution analysis revealed large molecular differences betw...
