Equine health encompasses the study and management of diseases, disorders, and overall well-being of horses. It involves understanding various physiological systems, preventive care, and treatment strategies to maintain optimal health in equine populations. Common areas of focus include nutrition, infectious diseases, orthopedic conditions, and reproductive health. Research in equine health aims to advance knowledge on diagnostic methods, therapeutic interventions, and management practices that improve horse welfare and performance. This page collects peer-reviewed research studies and scholarly articles that explore the diverse aspects of equine health, offering insights into current findings and advancements in the field.
Staszyk C.The routine inspection of the equine oral cavity allows a numerical assessment of the teeth and provides information about positional changes within the dentition. By use of appropriate dental equipment, the occlusal surfaces of all teeth can be inspected and diagnosed. However, neither the teeth nor their occlusal surfaces are constant structures. Instead, equine teeth and, in particular, their occlusal surfaces are subjected to continuous morphological and positional changes due to the effects of aging and the equine-specific high amount of occlusal wear. Therefore, it is mandatory to define...
Pusterla N, Mapes S, Akana N, Barnett C, MacKenzie C, Gaughan E, Craig B, Chappell D, Vaala W.The objective of the present case-control study was to determine prevalence factors associated with the detection of equine herpesvirus type 1 (EHV-1) by quantitative PCR (qPCR) in horses presented to veterinarians with clinical signs related to an upper respiratory tract infection and/or acute onset of neurological disease from March 2008 to December 2014. Nasal secretions and whole blood from 4228 equids with acute onset of fever, respiratory signs and/or neurological deficits were tested by qPCR for EHV-1. Categorical analyses were performed to determine the association between observations...
Cavalcante AL, Dias LM, Alves JT, Veras AA, Guimarães LC, Rocha FS, Gala-García A, Retamal P, Ramos RT, Azevedo V, Silva A, Carneiro AR.Corynebacterium pseudotuberculosis is related to several diseases infecting horses and small ruminants, causing economic losses to agribusiness. Here, we present the genome sequence of C. pseudotuberculosis strain E19. The genome includes one circular chromosome 2,367,956 bp (52.1% G+C content), with 2,112 genes predicted, 12 rRNAs, and 48 tRNAs.
Silva MLCR, Auguste AJ, Terzian ACB, Vedovello D, Riet-Correa F, Macário VMK, Mourão MPG, Ullmann LS, Araújo JP, Weaver SC, Nogueira ML.Madariaga virus (MADV), the new species designation for the South American isolates of eastern equine encephalitis virus (EEEV), is genetically divergent and substantially different in ecology and pathogenesis from North American EEEV strains. We isolated and characterized a MADV isolate obtained from a horse in Brazil. Our results support previous phylogenetic studies showing there are three genetically distinct MADV lineages. The MADV isolate from Paraíba State belongs to the South American lineage III and is closely related to Peruvian, Colombian and Venezuelan isolates.
Riera FL, Roldán JE, Gomez J, Hinrichs K.Transfer of donor oocytes to the oviducts of inseminated recipient mares (oocyte transfer, OT) presents a valuable method for production of foals from otherwise infertile mares. Little information is available, however, on factors affecting success of OT in a clinical setting. We report the findings over three breeding seasons in a commercial OT program developed at an equine embryo transfer center in Argentina. Overall, 25 mares were enrolled, and 197 follicle aspiration procedures were performed. The average mare age was 23 years. Follicle aspiration was performed with a needle placed throug...
Burger D, Dolivo G, Wedekind C.Sperm competition theory predicts semen characteristics to be affected by the social environment. We used the polygamous horse (Equus caballus) to experimentally study within-subject plasticity in response to different social environments. Stallions were sequentially exposed, over a period of 8 weeks each, to other stallions and then singly to mares, or vice versa (in adjacent boxes separated by grills). Ejaculates were collected to determine semen characteristics. Highest sperm numbers were found in stallions that were first exposed to other stallions and then to mares, while lowest sperm num...
Aguiar FL, Lunardi FO, Lima LF, Rocha RM, Bruno JB, Magalhães-Padilha DM, Cibin FW, Rodrigues AP, Gastal MO, Gastal EL, Figueiredo JR.This study investigated the effect of insulin concentration on the in vitro culture of equine preantral follicles enclosed in ovarian tissue. Ovarian tissue samples were immediately fixed (noncultured control) or cultured for 1 or 7 days in α-MEM(+) supplemented with 0 ng/mL, 10 ng/mL, or 10 μg/mL insulin. Ovarian tissues were processed and analyzed by classical histology. Culture medium samples were collected after 1 and 7 days of culture for steroid and reactive oxygen species (ROS) analyses. The percentage of morphologically normal follicles was greater (P < 0.001) in insulin-treated grou...
Diel de Amorim M, Nairn D, Manning S, Dedden I, Ripley E, Nielsen K, Card C.Ultrasound-guided biopsies of corpora lutea have been previously used for research purposes in the mare and cow. However, the health effects and fertility after transvaginal luteal biopsies (TVLB) or transvaginal ovarian biopsies (TVOB) obtained for diagnostic purposes in cases of suspected ovarian tumors have not been previously evaluated in the horse. The aim of this study was to determine the effects on health and fertility of TVLB and TVOB in mares; 53 mares were included in the study (11 control non-biopsied mares, 37 TVLB mares biopsied on one or more of the following Days 8, 10, 12, 15,...
Sheahan BJ, Wilkins PA, Lascola KM, Martin V, Po E.Prior studies have shown the prognostic utility of measuring L-lactate in critically ill neonatal foals, both as single (at admission) and serial measurements. Greater prognostic sensitivity and specificity may be achieved by use of the area under the L-lactate versus time curve (LACArea ) over the first 24 hours of hospitalization, which captures both severity and duration of hyperlactatemia. Prior to application of this concept in sick equine neonates, a reference interval for LACArea should be determined. Methods: The concentration of lactate [LAC] was measured in blood obtained via direct ...
Conde Ruiz C, Cruz Benedetti IC, Guillebert I, Portier KG.This prospective blinded randomized study aimed to determine whether the timing of morphine and phenylbutazone administration affects the breathing response to skin incision, recovery quality, behavior, and cardiorespiratory variables in horses undergoing fetlock arthroscopy. Ten Standardbred horses were premedicated with acepromazine (0.04 mg kg(-1) IM) and romifidine (0.04 mg kg(-1) IV). Anesthesia was induced with diazepam (0.05 mg kg(-1)) and ketamine (2.2 mg kg(-1)) IV at T0. Horses in group PRE (n = 5) received morphine (0.1 mg kg(-1)) and phenylbutazone (2.2 mg kg(-1)) I...
Brink P, Schumacher J.To describe canaliculosinostomy performed to resolve epiphora caused by nasolacrimal duct obstruction and to report the outcome of horses undergoing this procedure. Methods: Case series. Methods: Seven horses with uni- or bilateral nasolacrimal duct obstruction. Methods: The ventral lacrimal punctum and canaliculus were expanded with catheters of increasing diameter until a 14 gauge, Jamshedi needle could be passed into and through the lacrimal sac into the caudal maxillary sinus. One end of a plastic tube was inserted through the needle into the sinus, and the needle was withdrawn over the tu...
Toombs-Ruane LJ, Riley CB, Kendall AT, Hill KE, Benschop J, Rosanowski SM.To describe antimicrobial susceptibility, and identify antimicrobial resistance (AMR), in bacteria isolated from New Zealand foals. Methods: A database search was performed of submissions to a veterinary pathology laboratory between April 2004 and December 2013 for bacterial culture of samples from foals <3 weeks of age. Culture and susceptibility results were compiled with demographic information. Susceptibility results were as defined for the Kirby-Bauer disk diffusion susceptibility test based on Clinical Laboratory Standards Institute guidelines. Multi-drug resistance (MDR) was defined as ...
Balao da Silva CM, Ortega-Ferrusola C, Morrell JM, Rodriguez Martínez H, Peña FJ.To date, the only repeatable method to select spermatozoa for chromosomal sex is the Beltsville sorting technology using flow cytometry. Improvement of this technology in the equine species requires increasing awareness of the modifications that the sorting procedure induces on sperm intactness. Oxidative stress is regarded as the major damaging phenomenon, and increasing evidence regards handling of spermatozoa - including sex sorting - as basic ground for oxidative damage. The aim of this study was to disclose whether the flow cytometric sorting procedure increases the production of reactive...
Marycz K, Kornicka K, Basinska K, Czyrek A.Currently, equine metabolic syndrome (EMS), an endocrine disease linked to insulin resistance, affects an increasing number of horses. However, little is known about the effect of EMS on mesenchymal stem cells that reside in adipose tissue (ASC). Thus it is crucial to evaluate the viability and growth kinetics of these cells, particularly in terms of their application in regenerative medicine. In this study, we investigated the proliferative capacity, morphological features, and accumulation of oxidative stress factors in mesenchymal stem cells isolated from healthy animals (ASCN) and horses s...
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.
Pavulraj S, Bera BC, Joshi A, Anand T, Virmani M, Vaid RK, Shanmugasundaram K, Gulati BR, Rajukumar K, Singh R, Misri J, Singh RK, Tripathi BN....Equine influenza viruses (EIV)-H3N8 continue to circulate in equine population throughout the world. They evolve by the process of antigenic drift that leads to substantial change in the antigenicity of the virus, thereby necessitating substitution of virus strain in the vaccines. This requires frequent testing of the new vaccines in the in vivo system; however, lack of an appropriate laboratory animal challenge model for testing protective efficacy of equine influenza vaccine candidates hinders the screening of new vaccines and other therapeutic approaches. In the present investigation, BALB/...
Donadeu FX, Esteves CL.Pluripotent stem cells (PSCs) hold, through the capacity to differentiate into virtually all body cell types, unprecedented promise for human and animal medicine. PSCs are naturally found in the early embryo, and in rodents and humans they can be robustly harvested and grown in culture in the form of embryonic stem cells (ESCs); however, the availability of ESCs from horses is limited. ES-like cells named induced pluripotent stem cells (iPSCs) can be derived in vitro by transcription factor-mediated reprogramming of adult cells. As such, iPSCs can be generated in a patient-specific manner prov...
Do KT, Cho HW, Badrinath N, Park JW, Choi JY, Chung YH, Lee HK, Song KD, Cho BW.Since ancient days, domestic horses have been closely associated with human civilization. Today, horse racing is an important industry. Various genes involved in energy production and muscle contraction are differentially regulated during a race. Among them, creatine kinase (CK) is well known for its regulation of energy preservation in animal cells. CK is an iso-enzyme, encoded by different genes and expressed in skeletal muscle, heart, brain and leucocytes. We confirmed that the expression of CK-M significantly increased in the blood after a 30 minute exercise period, while no considerable c...
Hori Y, Tozaki T, Nambo Y, Sato F, Ishimaru M, Inoue-Murayama M, Fujita K.Tractability, or how easily animals can be trained and controlled, is an important behavioural trait for the management and training of domestic animals, but its genetic basis remains unclear. Polymorphisms in the serotonin receptor 1A gene (HTR1A) have been associated with individual variability in anxiety-related traits in several species. In this study, we examined the association between HTR1A polymorphisms and tractability in Thoroughbred horses. We assessed the tractability of 167 one-year-old horses reared at a training centre for racehorses using a questionnaire consisting of 17 items....
Froydenlund TJ, Dixon PM, Smith SH, Reardon RJ.The morphology of the dorsal conchal bulla (DCB) and ventral conchal bulla (VCB) are poorly described. The recent recognition that these bullae can become infected, causing chronic unilateral nasal discharge, has stimulated interest in these structures. Fourteen cadaveric horse heads were transected sagittally midline and dissected to expose the nasal conchal bullae. The dimensions of each bulla, the number and orientation of drainage apertures, and cellulae septae were recorded. Randomly selected samples were examined histologically. The mean DCB and VCB lengths were 78 and 57 mm, respec...
Campolo A, de Laat MA, Keith L, Gruntmeir KJ, Lacombe VA.Insulin dysregulation is common in horses although the mechanisms of metabolic dysfunction are poorly understood. We hypothesized that insulin signaling in striated (cardiac and skeletal) muscle and lamellae may be mediated through different receptors as a result of receptor content, and that transcriptional regulation of downstream signal transduction and glucose transport may also differ between tissues sites during hyperinsulinemia. Archived samples from horses treated with a prolonged insulin infusion or a balanced electrolyte solution were used. All treated horses developed marked hyperin...
Selvaggi M, D'Alessandro AG, Dario C.The aims of this study were to assess the genetic variability in the exon 1 of the κ-casein gene in four Italian horse populations (Italian Saddle horse, Italian Trotter, Italian Heavy Draught horse, and Murgese horse) and in a sample of Martina Franca donkey by estimating genotype, allele and haplotype frequencies, as well as several population genetic indices. Genotyping of the selected polymorphisms was performed using the PCR-RFLP technique with two restriction enzymes: PstI and BseYI aimed to discover the presence of c.-66A>G and c.-36C>A polymorphism, respectively. Both these loci...
Schweizer C, Ramseyer A, Gerber V, Christen G, Burger D, Wohlfender FD.Racetrack injuries are of welfare concern and the prevention of injuries is an important goal in many racing jurisdictions. Over the years this has led to more detailed recording of clinical events on racecourses. However, risk factor analyses of clinical events at race meetings have not been previously reported for Switzerland. Objective: To identify discipline-specific factors that influence the occurrence of clinical events during race meetings with the ultimate aim of improving the monitoring and safety of racetracks in Switzerland and optimising racehorse welfare. Methods: Retrospective s...
Petersen GF, Hilbert BJ, Trope GD, Kalle WH, Strappe PM.The ability to culture neurons from horses may allow further investigation into equine neurological disorders. In this study, we demonstrate the generation of induced neuronal cells from equine adipose-derived stem cells (EADSCs) using a combination of lentiviral vector expression of the neuronal transcription factors Brn2, Ascl1, Myt1l (BAM) and NeuroD1 and a defined chemical induction medium, with βIII-tubulin-positive induced neuronal cells displaying a distinct neuronal morphology of rounded and compact cell bodies, extensive neurite outgrowth, and branching of processes. Furthermore, we ...
Jönsson L, Madsen P, Mark T.Genetic evaluations of sport performance typically consider competition records of ranking points in each competition, accumulated lifetime points or annual earnings. Repeated observations have the advantage of allowing for adjustment of effects associated with each competition such as rider experience, judge and competing horses, but also demands more computer capacity than single-trait records, which could prohibit multiple-trait evaluations. The aim of the study was to compare CPU times, estimated breeding values (EBVs), reliabilities and model prediction abilities when modelling repeated c...
Aharonson-Raz K, Baneth G, Lopes AP, Brancal H, Schallig H, Cardoso L, Steinman A.A cross-sectional investigation was done on the seroprevalence of Leishmania infantum and Toxoplasma gondii infection among apparently healthy horses in Israel. This survey included 383 horses distributed in 22 farms throughout Israel during the years 2011-2013. Serum samples were tested for the presence of immunoglobulin G (IgG) antibodies using the direct agglutination test (DAT) specific to Leishmania and by the modified agglutination test (MAT) for the presence of IgG antibodies to T. gondii. Low seroprevalences were detected for both L. infantum and T. gondii in the horse population in Is...
Cesarini C, Cotovio M, Ríos J, Armengou L, Jose-Cunilleras E.Disseminated intravascular coagulation (DIC) is frequent in horses with severe gastrointestinal disorders. Postmortem studies have found fibrin microthrombi in tissues of these horses, but studies relating these histopathological findings with antemortem hemostatic data are lacking. Objective: Antemortem classification of coagulopathy is related to the presence and severity of fibrin deposits observed postmortem in horses with severe gastrointestinal disorders. Methods: Antemortem hemostatic profile data and postmortem tissue samples (kidney, lung, liver) from 48 horses with colic. Methods: Ti...
Saey V, Famaey N, Smoljkic M, Claeys E, van Loon G, Ducatelle R, Ploeg M, Delesalle C, Gröne A, Duchateau L, Chiers K.Thoracic aortic rupture and aortopulmonary fistulation are rare conditions in horses. It mainly affects Friesian horses. Intrinsic differences in biomechanical properties of the aortic wall might predispose this breed. The biomechanical and biochemical properties of the thoracic aorta were characterized in warmblood horses, unaffected Friesian horses and Friesians with aortic rupture in an attempt to unravel the underlying pathogenesis of aortic rupture in Friesian horses. Samples of the thoracic aorta at the ligamentum arteriosum (LA), mid thoracic aorta (T1) and distal thoracic aorta (T2) we...
Santos FC, Corcini CD, Costa VG, Gheller SM, Nogueira CE, da Rosa Curcio B, Varel AS.Solid storage medium prevents cellular sedimentation, reduces metabolic demand via limiting movement, and avoids the modification of an extender composition in the sedimentary microenvironment. It has been proven to prolong spermatozoa viability in mammalians. Objective: This experiment aims to evaluate the effect of cool storage in solid phase extender on stallion sperms. Methods: Semen was collected from 10 Crioulo stallions (n=30) and submitted to treatments: control group (semen extender) and groups with gelatin addition in different concentrations (semen extender + 1%, 2% and 3%). Seminal...
Kohn CW, Hinchcliff KW.Physiological data were collected during two 3-day-event competitions: one (H) held in hot and the other (CL) in cool conditions. During H, ambient temperature and relative humidity were 2.5 degrees C-35 degrees C and 74-36% respectively, while during CL, ambient temperature and relative humidity were 7.8 degrees C-8.3 degrees C and 46%-41%, respectively. Rectal temperature, heart and respiratory rates were recorded on arrival at the event, at the end of Phase C and 6 min later, at the end of Phase D and for 30 min at 10 min intervals after each horse finished Phase D (Recovery Period). Becaus...
Dietze K, Slosarek I, Fuhrmann-Selter T, Hopperdietzel C, Plendl J, Kaessmeyer S.Arterial or venous thromboses are frequent clinical complications with the risk of fatal progression. Recent studies suggest the disruption of angiogenesis in the course of thrombus resolution as the underlying pathomechanism. Very similar to the situation in human patients, equine vessels have been described to be particularly susceptible to thrombosis. In contrast to humans, equine donors are readily available to obtain organs and tissues for isolation of endothelial cells. Objective of this study was to isolate equine endothelial cells and develop an angiogenesis assay from primary cultures...
Sandbaumhüter FA, Aerts JT, Theurillat R, Andrén PE, Thormann W, Jansson ET.The chiral drug ketamine has long-lasting antidepressant effects with a fast onset and is also suitable to treat patients with therapy-resistant depression. The metabolite hydroxynorketamine (HNK) plays an important role in the antidepressant mechanism of action. Hydroxylation at the cyclohexanone ring occurs at positions 4, 5, and 6 and produces a total of 12 stereoisomers. Among those, the four 6HNK stereoisomers have the strongest antidepressant effects. Capillary electrophoresis with highly sulfated γ-cyclodextrin (CD) as a chiral selector in combination with mass spectrometry (MS) was us...
Galey FD.Botulism should be considered in cases where weakness, paralysis, or intolerance to exercise might be seen in the horse. Dysphagia may also be present, although it is not a consistent finding. Potential sources include carrion in hay, moldy or otherwise rotted vegetation or forage, birds carrying material from animal burial or other similar sites, and contaminated carcasses on-site. Horses, especially foals, may also suffer from toxicoinfectious botulism, a condition where the C. botulinum might colonize and produce toxin within the gastrointestinal tract. Wounds also may harbor the organism a...
Vos NJ, Ducharme NG.The purpose of this paper was to identify factors that would positively or negatively affect the short-term survival rate of foals with septic arthritis. Medical records of 81 foals (≤seven months of age) with a clinical diagnosis of septic arthritis, referred to the equine hospital at Cornell University Hospital for Animals, between 1994 and 2003 were reviewed. Signalment, age at presentation, number of affected joints, joint fluid parameters, bacterial agents, treatment modalities and year of treatment were compared between survivors and nonsurvivors. Sixty-two of 81 foals (77%) were disch...
Pille F, De Baere S, Ceelen L, Dewulf J, Croubels S, Gasthuys F, De Backer P, Martens A.To determine radiocarpal (RC) joint synovial fluid and plasma ceftiofur concentrations after regional intravenous perfusion (RIP) and systemic intravenous (IV) administration. Methods: Experimental cross-over study. Methods: Five normal adult horses. Methods: One RC joint was randomly selected for RIP and the contralateral RC joint was sampled to determine intrasynovial ceftiofur concentrations after IV administration. Wash-out between IV and RIP was > or = 14 days. After surgical introduction of an intraarticular catheter, ceftiofur (2 g) was administered under general anesthesia either IV or...
Nielsen MK, Reist M, Kaplan RM, Pfister K, van Doorn DC, Becher A.Due to widespread development of anthelmintic resistance in equine parasites, recommendations for their control are currently undergoing marked changes with a shift of emphasis toward more coprological surveillance and reduced treatment intensity. Denmark was the first nation to introduce prescription-only restrictions of anthelmintic drugs in 1999, but other European countries have implemented similar legislations over recent years. A questionnaire survey was performed in 2008 among Danish horse owners to provide a current status of practices and perceptions with relation to parasite control....
Morris EA, Seeherman HJ.Forty-six racehorses with a history of poor performance underwent endoscopic evaluation of laryngeal and pharyngeal function while exercising on a high-speed treadmill. This evaluation allowed the definitive diagnosis of intermittent or continual upper respiratory tract obstruction as a cause of poor performance, as well as the documentation of the dynamic functional anatomy of the obstruction. Ten of the horses (22%) were determined to have a functional abnormality of the upper respiratory tract. These abnormalities included epiglottic entrapment (1 horse), persistent dorsal displacement of t...
Bruemmer JE.The ability to harvest and preserve epididymal sperm from a stallion after simple elective castration, a catastrophic injury, or severe acute illness and subsequent death has been realized, allowing for the preservation of genetics that would have been lost otherwise.Currently, the care taken to collect the testes and epididymides properly, coupled with proper packaging and shipping, could make the greatest contribution to salvaging viable sperm. As advances in assisted reproductive techniques continue, more offspring may be obtained from stored epididymal sperm from valuable stallions.
Cunningham FM, Dunkel B.Recurrent airway obstruction (RAO) and insect bite hypersensitivity (IBH) are allergic conditions that are commonly encountered in the horse. Whilst complete allergen avoidance is an effective management strategy for both diseases, this may not be achievable in all cases and treatment options are therefore required. The inflammatory response is the main therapeutic target for glucocorticoids given to horses with RAO and severe cases of IBH, whilst the bronchodilators used in RAO primarily target airway smooth muscle. Such drugs are effective in most but not all individuals and there may be unw...
Ahmed H, Chatterjee BP, Kelm S, Schauer R.A sialic acid-specific lectin, scorpin, has been purified to apparent homogeneity from the Indian scorpion Heterometrus granulomanus by affinity chromatography on equine submandibular gland glycopeptides linked to Sepharose and gel filtration on Sephadex G-200. The lectin has a molecular mass of 500 000 Da and was dissociated into single polypeptide chains of 15 000 Da, as determined by SDS gel electrophoresis in the presence of 2-mercaptoethanol. Scorpin is a glycoprotein containing 2.8% sugars. Its specificity was investigated by the inhibition of hemagglutination with various derivatives of...
Deaton CM, Marlin DJ, Smith NC, Smith KC, Newton RJ, Gower SM, Cade SM, Roberts CA, Harris PA, Schroter RC, Kelly FJ.The relationship between hydrogen peroxide (H2O2) concentration in expired breath condensate (EBC) and cytology of the respiratory tract obtained from tracheal wash (TW) or bronchoalveolar lavage (BAL), and epithelial lining fluid (ELF) antioxidant status is unknown. To examine this we analysed the concentration of H2O2 in breath condensate from healthy horses and horses affected by recurrent airway obstruction (RAO), a condition considered to be an animal model of human asthma. The degree of airway inflammation was determined by assessing TW inflammation as mucus, cell density and neutrophil ...
Kil N, Ertelt K, Auer U.Changes in behaviour are often caused by painful conditions. Therefore, the assessment of behaviour is important for the recognition of pain, but also for the assessment of quality of life. Automated detection of movement and the behaviour of a horse in the box stall should represent a significant advancement. In this study, videos of horses in an animal hospital were recorded using an action camera and a time-lapse mode. These videos were processed using the convolutional neural network Loopy for automated prediction of body parts. Development of the model was carried out in several steps, in...
Motlou TP, Williams J, Venter M.The genus, family , contains several important emerging and re-emerging arboviruses of veterinary and medical importance. These viruses may cause mild febrile illness, to severe encephalitis, fetal deformity, abortion, hemorrhagic fever and death in humans and/or animals. Shuni virus (SHUV) is a zoonotic arbovirus thought to be transmitted by hematophagous arthropods. It was previously reported in a child in Nigeria in 1966 and horses in Southern Africa in the 1970s and again in 2009, and in humans with neurological signs in 2017. Here we investigated the epidemiology and phylogenetic relatio...
Duquesne F, Houssin E, Sévin C, Duytschaever L, Tapprest J, Fretin D, Hébert L, Laugier C, Petry S.Rhodococcus equi causes pulmonary and extrapulmonary infections in animals and humans, with endemic situations and significant young foal mortality in stud farms worldwide. Despite its economic impact in the horse-breeding industry, the broad geographic and host distribution, global diversity and population structure of R. equi remain poorly characterised. In this context, we developed a multilocus sequence typing (MLST) scheme using 89 clinical and environmental R. equi of various origins and eight Rhodococcus sp. Data can be accessed at http://pubmlst.org/rhodococcus/. A clonal R. equi popul...
Ellington JE, Ignotz GG, Varner DD, Marcucio RS, Mathison P, Ball BA.Coculture of stallion sperm with monolayers of equine oviductal epithelial cells (OEC) was evaluated. Monolayers were obtained from frozen-thawed OEC. Live sperm attached to the OEC in vitro, whereas sperm killed by heat treatment or glutaraldehyde fixation did not. Sperm attached to OEC showed flagellar motion for 4 d in vitro, during which time they gradually became released. Scanning electron-micrographs showed an intimate association between the sperm and OEC. Incubation of sperm for 4 h with either control, heparinized or OEC-conditioned medium (Tyrode's albumin lactate phosphate) resulte...
MacKay RJ.After inflammation is initiated by detection of antigen, plasma components and activated leukocytes are concentrated at the inflammatory site. Cellular and chemical effectors of inflammation are focused on the offending antigen, usually resulting in its destruction and elimination. Activation of endogenous counter-regulatory systems damps down the inflammatory process and is the first stage of repair. In addition to local effects, the inflammatory focus may initiate a continuum of systemic acute phase responses ranging from the systemic inflammatory response syndrome (SIRS) to generalized immu...
Kamm JL, Riley CB, Parlane NA, Gee EK, McIlwraith CW.Mesenchymal stromal cells (MSCs) are believed to be hypoimmunogeneic with potential use for allogeneic administration. Bone marrow was harvested from Connemara (n = 1), Standardbred (n = 6), and Thoroughbred (n = 3) horses. MSCs were grouped by their level of expression of major histocompatibility factor II (MHC II). MSCs were then sub-grouped by those MSCs derived from universal blood donor horses. MSCs were isolated and cultured using media containing fetal bovine serum until adequate numbers were acquired. The MSCs were cultured in xenogen-free media for 48 h prior to use and d...
DuBois C, Hambly-Odame H, Haley DB, Merkies K.As part of a larger Delphi survey project, equine professionals ( = 14) were presented with twelve short scenarios in which a horse's welfare could be compromised. They were asked to rank each scenario (with 0 indicating no welfare concerns and 5 indicating a situation where immediate intervention was necessary), provide justification for their ranking, and give examples of what might have been the motivation behind the scenario. The wide range within vignette scores demonstrated the diversity of opinion even among a relatively small group of equine professionals. Qualitative analysis of respo...
Purefoy Johnson J, Stack JD, Rowan C, Handel I, O'Leary JM.To compare accuracy of the ultrasound-guided craniodorsal (CrD) approach with the dorsal (D) approach to the cervical articular process joints, and to evaluate the effect of the transducer, needle gauge, and operator experience. Methods: Cervical articular process joints from 14 cadaveric neck specimens were injected using either a D or CrD approach, a linear (13 MHx) or microconvex transducer (10 MHz), and an 18 or 20 gauge needle, by an experienced or inexperienced operator. Injectate consisted of an iodinated contrast material solution. Time taken for injection, number of redirects, and ret...
Holmes JR, Alps BJ.Theoretical consideration has been given in two horses to the properties of the electric field created by the equine heart acting as a simple electric generator. The principles of the vectorial theory have been applied to test the validity of application of the dipole concept. The cardiac electric forces, althrough complex in the immediate region of the heart, appear at the body surface in a similar form to those arising from a relatively immobile, single equivalent dipole. The potential value of the technique of vectorcardiography in cardiological investigations is briefly discussed.
Tamanini C, Giordano N, Chiesa F, Seren E.Plasma cortisol variations have been determined by radioimmunoassay in 5 stallions during mating and in 2 teasers during oestrous female exposure. In all the animals, cortisol plasma levels consistently increase (71.1 ng/ml vs 44.0 and 63.0 ng/ml vs 35.1, in the stallions and in the teasers, respectively) 7-30 min after female exposure; 120 min after exposure, cortisol concentrations are again low.
Machang'u RS, Prescott JF.Rhodococcus equi produces two exoenzymes (REE), a cholesterol oxidase in large amounts and a phospholipase C, which cause lysis of sheep red blood cells (SRBC) sensitized with Staphylococcus aureus beta toxin. Two immunization studies were done in foals to determine the role of antibody to REE in protection against R. equi pneumonia. In the first study, three foals (mean age 10 days) were vaccinated four times at 2-week intervals with over 1 million units of partially purified exoenzymes (PREE). In the second study, three foals (mean age 19 days) were administered plasma from an adult horse va...
Neto AC, Ball BA, Browne P, Conley AJ.Elevated blood testosterone concentrations, often accompanied by male-typical behaviors, is a common signalment of mares with granulosa-theca cell tumors (GCTCs), but no definitive information exists regarding the cellular differentiation of tumors associated with androgen secretion. This study was conducted to localize and thereby define the cellular expression of 17alpha-hydroxylase/17,20-lyase cytochrome P450 (P450c17), the enzyme most directly responsible for androgen synthesis, in 30 GTCTs and control tissues (gonads and adrenal glands) using immuno-histochemistry (IHC). Immuno-reactivity...
Jansen MO, van Raaij JA, van den Bogert AJ, Schamhardt HC, Hartman W.The function of several intrinsic muscles of the fore-and hind limbs of 5 ponies walking normally was evaluated via surface electromyography. Electromyographic signals were band-pass filtered, rectified, linear enveloped, and standardized to the stride duration. Mean data from the muscles of the left and right limbs that were obtained from at least 30 strides in 2 recording sessions were recorded as electromyographic signals-time curves. The timing of muscle activity was determined from these graphs. On the basis of the major peaks in the electromyographic signal, muscle functions were identif...
van Ginneken MM, de Graaf-Roelfsema E, Keizer HA, van Dam KG, Wijnberg ID, van der Kolk JH, van Breda E.To investigate the effects of exercise on activation of mitogen-activated protein kinase (MAPK) signaling proteins in horses. Methods: 6 young trained Standardbred geldings. Methods: Horses performed a 20-minute bout of exercise on a treadmill at 80% of maximal heart rate. Muscle biopsy specimens were obtained from the vastus lateralis and pectoralis descendens muscles before and after exercise. Amount of expression and intracellular location of phosphospecific MAPK pathway intermediates were determined by use of western blotting and immunofluorescence staining. Results: Exercise resulted in a...
Santschi EM, Slone DE, Frank WM.During a 28 month period, 82 horses with clinical signs of abdominal pain were examined for left dorsal displacement of the large colon (LDDLC) using percutaneous ultrasound. Left dorsal displacement of the large colon was diagnosed when a gas echo dorsal to the spleen obliterated the dorsal splenic border, or when the colon was observed lateral to the spleen. In 42 horses, ultrasound confirmed a diagnosis of LDDLC and 40 horses had no evidence of LDDLC. There were five false negative results and no false positives. In four horses with LDDLC, the colon was displaced between the spleen and body...
