Veterinary medicine for horses encompasses the study and application of medical practices to diagnose, treat, and prevent diseases in equine species. This field involves a comprehensive understanding of equine anatomy, physiology, pathology, and pharmacology. Veterinary practitioners employ a range of diagnostic tools and therapeutic interventions to address health issues in horses, including lameness, gastrointestinal disorders, respiratory conditions, and infectious diseases. Preventative care, such as vaccination and deworming programs, is also a significant aspect of equine veterinary medicine. This page gathers peer-reviewed research studies and scholarly articles that explore various aspects of veterinary medicine as it pertains to horses, including advancements in diagnostic techniques, treatment protocols, and preventive health strategies.
Sun YF, Han ZX, Yao XK, Meng J, Ren WL, Wang CK, Yuan XX, Zeng YQ, Wang YF, Sun ZW, Wang JW.: The aim of this study was to investigate the effects of different stages of training on the intestinal microbial abundance of Yili horses. : Ten Yili horses, all aged 2 years old and weighing 305 ± 20 kg, were selected and divided into a training group and an untrained group. The training group performed riding training 6 days a week, and the untrained group moved freely in the activity circle every day. Fecal samples were collected on days 30 and 60, and the intestinal microorganisms were detected and analyzed using metagenomics. : Compared with the 30-day untrained group, the relative abu...
Hallman IAM, Raekallio MR, Karikoski NP.Vatinoxan is a peripherally acting alpha2-adrenoceptor antagonist used in veterinary medicine to attenuate the side effects of alpha2-adrenoceptor agonists. Vatinoxan also increases insulin response and reduces blood glucose (BG) after intravenous glucose in other species. The aim of this study was to investigate the effects of vatinoxan on BG and insulin concentration in horses after intravenous glucose. The design was an assessor-blind cross-over study. Nine horses were assigned to intravenous vatinoxan (0.2 mg/kg; VAT) or saline (SAL). Horses were administered an intravenous glucose bolus (...
Sterkenburgh TR, Ordieres-Meré J, Villalba-Diez J.We outlined a monitoring system as a demonstration of the Internet of Medical Things (IoMT) in horses that provided the ability to record aspects of the equine chewing process. Here we take up the idea of a Molograph, which was already proposed in the mechanical form in 1941 by Leue and transferred into today's world. As a substantial practical advantage, the system now involved a non-invasive measurement that was taken in the horse's familiar environment. All patients were fed roughage. In terms of the examination scenario, we focused on the determination of the direction of chewing. The syst...
Cameron-Whytock H, Divall H, Lewis M, Apps C.The study hypothesised that a markerless motion capture system can provide kinematic data comparable to a traditional marker-based system for riders mounted on a horse. The objective was to assess the markerless system's accuracy by directly comparing joint and segment angle measurements taken during walking and trotting with those obtained from a marker-based system. Ten healthy adult participants performed five dynamic trials during walking and trotting. A twelve-camera marker-based system and eight-camera 2D video-based system were synchronised. Three-dimensional hip, knee, shoulder and elb...
Midon M, Clark-Price SC, Lin HC, Lascola KM, Boone L.To determine if serum iron concentrations decrease acutely during and after general anesthesia in healthy horses. Methods: Prospective experimental study. Methods: A convenience sample of 24 healthy adult horses (eight females, 16 geldings), weighing 545 ± 33 kg (mean ± standard deviation). Methods: Horses were anesthetized for 120 minutes with isoflurane, after premedication with intravenous (IV) xylazine (0.8 mg kg-1) and induction with IV midazolam (0.1 mg kg-1) and ketamine (2.2 mg kg-1). Blood samples for serum iron analysis were obtained just before premedication (baseline), after 60 m...
Lundmark Hedman F, Ewerlöf IR, Frössling J, Berg C.The presence of a trustworthy and effective animal welfare control system is important both for animal welfare and for public and consumer trust. The inspectors' main task, regardless of whether they are official inspectors or private auditors, is to check for and enforce compliance with any relevant regulations. The aim of this study was to investigate how official animal welfare inspectors and private animal welfare auditors in Sweden perceive their inspection work and to explore any differences in the perception of being an inspector between these two groups. An electronic questionnaire was...
Renaudin CD, Picandet V, Kass PH.Using the equation of Hartwig et al. and the table established for light breed horses, day of gestation was predicted in 108 Warmblood (WB) and 59 racehorses (Thoroughbred [TB] and Standardbred [STB]) pregnant mares. In WB, gestational ages were predicted within 2 weeks from 100 to 200 days of gestation using biparietal diameter (BPD), aortic diameter (AortD) or femur length (FL); within 2 weeks from 100 to 250 days using BPD or AortD; within 2 weeks from 100 to 300 days using BPD alone; and within 3 weeks from 100 to 350 days using eye approximated volume (EyV) alone. In the ...
Vernemmen I, Demeyere M, Van Steenkiste G, Buschmann E, Decloedt A, van Loon G.Ultrasonographic guidance of catheter-based interventions in horses is based primarily on transthoracic echocardiography (TTE). Intracardiac echocardiography (ICE) has the potential to provide detailed imaging of specific cardiac regions. Insight and training in echocardiographic guidance can be acquired using an echocardiography simulator. Objective: Use an echocardiography simulator for horses to determine specific ICE views for catheter-based interventions and validate these in live horses. Methods: Six adult healthy experimental horses. Methods: Observational study. An echocardiographic ph...
de la Rebière de Pouyade G, Binard M, Deleuze S, Ponthier J.Standing caesarian section (C-section) in mares is poorly documented in the literature. It is reportedly straightforward to perform for veterinarians experienced in bovine practice and is more accessible and less expensive than recumbent techniques. The study aimed to create a survey to report the outcomes of in field C-section through a flank laparotomy with the mare standing under sedation. Unassigned: A survey was developed for field veterinarians practicing standing C-sections. Data were collected regarding the veterinarian's experience and practice type, details about the mare and the rea...
Hansen S, Hopster-Iversen C, Berg L, Fjeldborg J, Massey C, Piercy RJ, Carstensen H.Exertional myopathies are recognised as a cause of poor performance in equines. In Icelandic horses presenting reduced performance and/or multi-limb lameness, no specific myopathy has been identified. Objective: To characterise the clinical presentation and histopathological findings in muscle biopsy samples from Icelandic horses demonstrating poor performance. Methods: Case series. Methods: Phenotypic characteristics, clinical examination and diagnoses of 17 Icelandic horses were studied. All horses had a resting serum creatine kinase (CK) and aspartate transaminase activities measured, and C...
Chevalier N, Migné CV, Mariteragi-Helle T, Dumarest M, De Mas M, Chevrier M, Queré E, Marcillaud-Pitel C, Lupo C, Bigeard C, Touzet T, Leblond A....The circulation of West Nile virus (WNV), Usutu virus (USUV), and tick-borne encephalitis virus (TBEV) was investigated in south-western France during the first six months of 2023, following the emergence of WNV in equids in Gironde, a département in south-western France, in 2022. Blood samples were collected from 494 horses located in the Gironde département and divided into three zones: the Confluence zone, the Intermediate zone and the Arcachon Basin. Samples were tested for WNV-, USUV- and TBEV-specific antibodies. An overall seroprevalence of 14% (95% CI [11-18%]) for orthoflavivirus an...
Macleod BM, Wilkins PA, McCoy AM, Bishop RC.Viscoelastic coagulation testing (VCT) identifies subclinical disruption of coagulation homeostasis and may improve prognostication, particularly for patients with severe systemic inflammation or shock. Machine learning (ML) algorithms may capture complex relationships between clinical variables better than linear regression (GLM). Objective: To evaluate the utility of ML models incorporating VCT and clinical data to predict survival outcomes in horses with acute abdominal pain. Methods: Retrospective observational cohort study. Methods: VCT (VCM Vet™) was performed on 57 horses with acute a...
Granados MM, Medina-Bautista F, Navarrete-Calvo R, Argüelles D, Domínguez-Pérez JM, Priego-Capote F, Muñoz-Rascón P, Serrano-Rodríguez JM.To date, no intravenous pharmacokinetics (PK) studies have assessed acetaminophen or its major metabolites (acetaminophen-glucuronide and acetaminophen-sulphate) in horses. The influence of sex on acetaminophen metabolism in horses is unclear, and Monte Carlo simulations have not been applied to explore potential clinical applications. This study aimed to determine the intravenous PK and safety of acetaminophen in Andalusian horses at 10 and 20 mg/kg, evaluate sex as a covariate, and simulate clinical regimens. Twenty mares and twenty stallions received intravenous acetaminophen, and plasma ...
Brown KA, Engiles JB, de Solis CN, Bills KW, Johnson AL, Davidson EJ.To determine the accuracy of a dorsal ultrasound-guided approach for perineural injection of the sixth and seventh cervical spinal nerves (CSNs) with the use of a clinically relevant volume of injectate (2 mL). We hypothesized that the majority of injections would result in identification of contrast solution in the intervertebral foramen (IVF) on CT and corresponding methylene blue dye staining of the CSN on postmortem evaluation, and distribution of injectate into the epidural space would not occur. Unassigned: 7 horses donated to the University of Pennsylvania New Bolton Center for euthanas...
Cole RC, DeGraves FJ, Brown J, Schumacher J.To compare the effect of 2.5 mL 2% mepivacaine to the effect of 0.5 mL 2% mepivacaine administered over each palmar digital nerve, as an abaxial sesamoid nerve block (ASNB), to 6 horses lame because of naturally occurring digital pain. Unassigned: In a crossover study design with 3 horses in each group, the trotting gait of the horses was analyzed with an inertial sensor-based, motion-analysis system (Q with Lameness Locator; Equinosis LLC) immediately before and after treatment with either 0.5 or 2.5 mL mepivacaine administered over each nerve near the base of the proximal sesamoid bone of th...
The inflammatory status in horses with gastric ulcers was monitored by two inflammatory biomarkers, S100A12 and adenosine deaminase (ADA), using saliva samples from healthy and horses with gastric ulcers. Two trials were developed: an experimental trial, in which gastric ulceration was induced in 8 horses by feed deprivation, and a clinical trial, in which 20 horses without any symptomatology and 37 with symptoms compatible with gastric ulcers were used. S100A12 and ADA levels were measured in the saliva samples of all horses using previously validated assays. In both trials, horses with gastr...
Conrad MB, Leatherwood JL, Paris BL, George JM, Martinez RE, Vergara-Hernandez FB, Nielsen BD, Colbath AC, Arnold CE, Glass KG, Welsh TH, Bradbery AN.Extra-label bisphosphonate (BP) use in juvenile horses is anecdotally reported, primarily for analgesic effects, despite the limited scientific understanding of biologic impacts on skeletally immature horses undergoing exercise. The objective of this study was to determine the effects of clodronate disodium (CD), a form of BP, on endocrine regulators of calcium. Thus, 32 yearling Quarter Horses were stratified by age (500 ± 13 d), body weight (BW; 336 ± 26 kg), sex (n = 16 geldings, n = 16 fillies), and initial bone optical density into 1 of 4 treatment groups for a 168-d tr...
Carbonell JD, Fernández N, Escobar MJ, Álvarez MT, Sánchez L, Hernández A, Meana A.Chorioptic mange is a challenging condition to treat due to the superficial locations of the nonhematophagous mite , and while topical acaricides are recommended, the clinical feature relapses are frequent. In a double-blinded clinical trial, three randomized groups of Spanish-Breton horses ( = 32) naturally infected with on their legs were evaluated over a period of 70 days. All treatments were applied once every 14 days for three treatments. Before treatment and on Day (D)10, D25, D37, D56, and D70, each leg per animal was scored according to equine pastern dermatitis clinical presentat...
Tulloch JSP, Schofield I, Jackson R, Whiting M.The veterinary industry has some of the highest rates of non-fatal work-related injuries, yet safety culture remains unexplored. Utilising a survey distributed to all UK employees of a consolidated group of veterinary practices, this study aimed to describe the prevalence of work-related injuries in equine, production animal, and mixed veterinary practices, and to understand the behaviours of injured persons. There were 144 respondents. Over 90 % of clinicians experienced injury during their careers, versus a third of non-clinical staff. Injuries to equine veterinarians were predominately ki...
Domínguez-Odio A, González LIC, Alfonso DM, Guevara-Hernández F, La O Arias MA, Zayas MP, Ríos MÁB.The transmembrane glycoprotein gp45 (implicated in virus-equine B lymphocyte binding and in subsequent infection) is an important protein used as an antigen in the serological diagnosis of equine infectious anemia, but synthetic peptides derived from its structure are not. Consequently, the present study aimed to determine the diagnostic performance of the Bio-AIELAB immunoassay (novel synthetic peptide P05/gp45) in comparison with a similar commercial assay (ELISA EIA, VMRD Inc, USA) and with the gold standard (AGID, LABIOFAM, Cuba). A total of 365 samples of sera from naturally infected Cuba...
Cheung HW, Wong KS, Cheng PCF, Tsang CYN, Farrington AF, Wan TSM, Ho ENM.Erythropoiesis-stimulating agents (ESAs) continue to be a significant threat to the integrity of human and equine sports. Besides conventional direct testing, monitoring the biomarkers associated with the effects of ESAs may provide a complementary approach via indirect detection to enhance doping control. In this study, we applied RNA-sequencing (RNA-seq) to discover blood RNA biomarkers in Thoroughbred horses after administration with a long-acting form of recombinant human erythropoietin (rhEPO), methoxy polyethylene glycol epoetin beta, Mircera®. A single subcutaneous administration of Mi...
Pawlina-Tyszko K, Semik-Gurgul E, Podstawski P, Herc W, Witkowski M, Ropka-Molik K.Alterations in the genes involved in the creation of the extracellular matrix (ECM) were observed in our earlier transcriptome studies of sarcoids and their cell culture model. For a complete characterization of the underlying molecular pathways, it is imperative to comprehend the involvement of ECM modifications in the oncogenic transformation of sarcoid fibroblasts. Thus, the aim of this investigation was to describe the expression patterns of a set of genes that are essential for the rearrangements of the extracellular matrix, namely collagen genes, and elucidate possible mechanisms underly...
Munsterman AS, Dias Moreira AS, Kottwitz J.To evaluate the effects of detomidine on equine intestinal slow-wave activity and frequency distribution measured by electrointestinography (EIG). Methods: Prospective, experimental study. Methods: University teaching hospital. Methods: A convenience sample of twelve 7- to 21-year-old clinically normal horses. Methods: Horses were randomly assigned to saline control (four horses) or detomidine treatment (eight). After obtaining a 30-min baseline EIG, a saline or detomidine bolus was administered, followed by a constant rate infusion, and another EIG was recorded. Ultrasonographic examinations ...
Morawska-Kozłowska M, Pitas M, Zhalniarovich Y.Mesenchymal stem cells (MSCs) hold significant therapeutic potential in veterinary medicine due to their regenerative and immunomodulatory properties. This review examines the clinical applications of MSCs across multiple animal species, including equine, canine, feline, and bovine medicine. MSC therapies have demonstrated promising outcomes in treating musculoskeletal disorders, osteoarthritis, inflammatory diseases, and tissue injuries, particularly in horses and dogs. In cats, MSCs show potential for managing chronic kidney disease, inflammatory bowel disease, and asthma, while in bovine me...
Gómez-Torres F, Ballesteros-Acuña L, Ruíz-Sauri A.Arrhythmic sudden cardiac death in dogs and horses often results from ventricular arrhythmia secondary to myocardial damage. Despite this, limited data exist on the histomorphometric changes in cardiac conduction fibers (CCFs) and cardiac conduction cells (CCCs) following spontaneous myocardial infarction (MI). This study aimed to characterize morphometric and histological alterations in conduction fibers and their junctions with cardiomyocytes in infarcted hearts of horses and dogs. Unassigned: Ten hearts from horses and 10 from dogs that had died suddenly were examined. Histological and immu...
Turek B, Jankowski K, Pawlikowski M, Jasiński T, Domino M.Proximal phalanx (P1) fractures in horses are relatively common, and present significant treatment challenges, especially when the fractures are comminuted or infected. An innovative treatment approach includes attaching an external fixator to the third metacarpal bone (MC III), the healthy bone above fracture, to offload the injured P1 and protect it from load-bearing forces, particularly during post-surgical standing up. This study aims to develop the favourable mathematical and numerical models for screws configuration in this external fixator. Nine configurations (I-IX), varying in screw a...
Kinoshita Y, Niwa H, Ueno T.In horses, the gut microbiota plays a critical role in maintaining intestinal homeostasis and overall health, but antimicrobial administration can disrupt its balance, resulting in dysbiosis, which can cause antibiotic-associated diarrhea. This study assessed the impact of intravenous cephalothin sodium administration on the equine gut microbiota by using microbial amplicon sequencing targeting the 16S-ITS-23S rRNA operon. Fecal samples from 39 clinically normal horses, 16 antibiotic-treated horses (cephalothin, n=5; minocycline, n=5; metronidazole, n=6, each administered for 5 days), and seve...
Carmona JU, López C.(1) Background: Tendon and ligament injuries are a leading cause of lameness in horses, with significant economic implications. Platelet-rich plasma (PRP) has gained attention for its regenerative potential, but its efficacy remains uncertain due to inconsistent study designs and reporting. (2) Methods: This systematic review, following the PRISMA guidelines, evaluated 22 studies (clinical and experimental) to assess the safety and efficacy of PRP in treating equine tendon and ligament injuries. The risk of bias was analyzed using the ROBINS-I and RoB 2.0 tools. (3) Results: PRP demonstrated a...
Cerullo A, Di Nicola MR, Scilimati N, Bertoletti A, Pollicino G, Moroni B, Pepe M, Nannarone S, Gialletti R, Passamonti F.Bacterial contamination of the surgical site in horses is a major risk factor for the development of surgical site infections (SSIs), which increase morbidity, mortality, the hospitalisation period, antibiotic use, and management costs. While contamination is a prerequisite for infection, its progression to clinical infection depends on additional factors that compromise host defences. The present study, conducted at the Veterinary Teaching Hospital of the University of Perugia over an 11-month period, investigated bacterial contamination in 70 surgeries (53 clean and 17 clean-contaminated) at...
Alberghina D, Tombolani C, Quintavalla F.Evaluating the body temperature of horses () is essential for monitoring their health. Rectal thermometry is the most common method for determining the temperatures of adult horses and foals. However, this method requires restraining the animals for several seconds, and it poses potential risks to both horses and humans. This study compared infrared and rectal thermometry in 126 horses, evaluating age and measurement site influences on body temperature. Horses were divided into three groups: foals (4-12 months), Shetland ponies (8-12 months), and adult horses (2-30 years). Rectal, ocular...
Moreau MM, Eades SC, Reinemeyer CR, Fugaro MN, Onishi JC.In the equine carbohydrate overload model of acute laminitis, disease progression is associated with changes in bacteria found in the cecum. To date, research has focused on changes in specific Gram-positive bacteria in this portion of the intestinal tract. Metagenomic methods are now available making it possible to interrogate microbial communities using animal protocols that sufficiently power a study. In this study, the microbiota in cecal fluid collected from control, non-laminitic horses (n=8) and from horses with early-stage acute laminitis induced with either oligofructan (n=6) or corns...
Nielsen MK, Peterson DS, Monrad J, Thamsborg SM, Olsen SN, Kaplan RM.Strongylus vulgaris is an important strongyle nematode with high pathogenic potential infecting horses world-wide. Several decades of intensive anthelmintic use has virtually eliminated clinical disease caused by S. vulgaris, but has also caused high levels of anthelmintic resistance in equine small strongyle (cyathostomin) nematodes. Recommendations aimed at limiting the development of anthelmintic resistance by reducing treatment intensity raises a simultaneous demand for reliable and accurate diagnostic tools for detecting important parasitic pathogens. Presently, the only means available t...
Christoffersen M, Woodward E, Bojesen AM, Jacobsen S, Petersen MR, Troedsson MH, Lehn-Jensen H.The objective of the study was to evaluate the gene expression of inflammatory cytokines (interleukin [IL]-1β, IL-6, IL-8, IL-10, tumor necrosis factor [TNF]-α, IL-1 receptor antagonist [ra] and serum amyloid A (SAA) in endometrial tissue and circulating leukocytes in response to uterine inoculation of 105 colony forming units (CFU) Escherichia coli in mares. Before inoculation, mares were classified as resistant or susceptible to persistent endometritis based on their uterine inflammatory response to infusion of 109 killed spermatozoa and histological assessment of the endometrial quality. ...
Reesink HL, Watts AE, Mohammed HO, Jay GD, Nixon AJ.The goals of this study were (1) to quantify proteoglycan 4 (PRG4) gene expression; (2) to assess lubricin immunostaining; and (3) to measure synovial fluid lubricin concentrations in clinical and experimental models of equine carpal osteoarthritis (OA). Lubricin synovial fluid concentrations and cartilage and synovial membrane PRG4 expression were analyzed in research horses undergoing experimental OA induction (n = 8) and in equine clinical patients with carpal OA (n = 58). Lubricin concentrations were measured using a custom sandwich enzyme-linked immunosorbent assay, and PRG4 expressio...
Roche SE, Wicks R, Garner MG, East IJ, Paskin R, Moloney BJ, Carr M, Kirkland P.To provide an overview and descriptive analysis of the 2011 arboviral disease epidemic in horses that involved three important Australian mosquito-borne viruses: Murray Valley encephalitis virus, West Nile virus (Kunjin strain) and Ross River virus. Methods: Data from states affected between January and June 2011 were collated and comprised reports of horses showing signs of neuromuscular disease and the associated laboratory findings. A summary of the data is presented, together with a spatiotemporal analysis of cases and preliminary assessment of rainfall patterns and case distribution. Resu...
Bullone M, Lavoie JP.Human asthma is a complex and heterogeneous disorder characterized by chronic inflammation, bronchospasm and airway remodeling. The latter is a major determinant of the structure-function relationship of the respiratory system and likely contributes to the progressive and accelerated decline in lung function observed in patients over time. Corticosteroids are the cornerstone of asthma treatment. While their action on inflammation and lung function is well characterized, their effect on remodeling remains largely unknown. An important hindrance to the study of airway remodeling as a major focu...
Newton JR, Wood JL, Dunn KA, DeBrauwere MN, Chanter N.During an outbreak of strangles on a farm with approximately 1500 horses, the spread of Streptococcus equi infection was monitored by repeated nasopharyngeal swabbing and culture. In order to control the infection and prevent new introductions of strangles on to the premises, a system of quarantine and swabbing of cases and all incoming animals was instituted. Long-term carriage of the organism was detected in four clinically healthy convalescent animals, and in two of 350 new ponies; it persisted for between seven and 39 months, but it was detected only intermittently by the culture of swabs ...
Poulet H, Minke J, Pardo MC, Juillard V, Nordgren B, Audonnet JC.The canarypox vaccine vector (ALVAC) technology has been used to develop and license several vaccines for companion animals and horses in the European Union and USA. ALVAC is a ubiquitous vector with high biosafety since it is non-replicative in mammalians, is genetically and physically stable, and able to induce both humoral and cell-mediated immune responses against the expressed transgene product. Specific rules apply for the development and registration of recombinant vector vaccines. The biology of the vector as well as the recombinant virus must be thoroughly documented to allow the risk...
Kolodziejek J, Dürrwald R, Herzog S, Ehrensperger F, Lussy H, Nowotny N.The aim of this study was to gain more detailed insights into the genetic evolution and variability of Borna disease virus (BDV). Phylogenetic analyses were performed on field viruses originating from naturally infected animals, the BDV vaccine strain 'Dessau', four widely used laboratory strains and the novel BDV subtype No/98. Four regions of the BDV genome were analysed: the complete p40, p10 and p24 genes and the 5'-untranslated region of the X/P transcript. BDV isolates from the same geographical area exhibited a clearly higher degree of identity to each other than to BDV isolates from ot...
Hulínská D, Langrová K, Pejcoch M, Pavlásek I.The aim of this study was to detect Anaplasma phagocytophilum in wild and domesticated animals and to identify the phylogenetic relationships of different strains of this bacterium. We adapted six published conventional methods targeting 16S fragments for real-time polymerase chain reaction. Initial screening of samples from 419 animals found 37 Anaplasma positives, later confirmed with several different primers and a TaqMan probe. We also performed DNA quantification and melting curve analysis. The nucleic acid of Anaplasma sp. was detected in a higher percentage of cases in members of the de...
Zhao Y, Holden VR, Smith RH, O'Callaghan DJ.The UL3 protein of equine herpesvirus 1 (EHV-1) KyA strain is a homolog of the ICP27 alpha regulatory protein of herpes simplex virus type 1 (HSV-1) and the ORF 4 protein of varicella-zoster virus. To characterize the regulatory function of the UL3 gene product, a UL3 gene expression vector (pSVUL3) and a vector expressing a truncated version of the UL3 gene (pSVUL3P) were generated. These effector plasmids, in combination with an EHV-1 immediate-early (IE) gene expression vector (pSVIE) and chimeric EHV-1 promoter-chloramphenicol acetyltransferase (CAT) reporter constructs, were used in trans...
Vázquez-Boland JA, Meijer WG.Rhodococcus equi is the only recognized animal pathogenic species within an extended genus of metabolically versatile Actinobacteria of considerable biotechnological interest. Best known as a horse pathogen, R. equi is commonly isolated from other animal species, particularly pigs and ruminants, and causes severe opportunistic infections in people. As typical in the rhodococci, R. equi niche specialization is extrachromosomally determined, via a conjugative virulence plasmid that promotes intramacrophage survival. Progress in the molecular understanding of R. equi and its recent rise as a nove...
Chan J, Doyle B, Branley J, Sheppeard V, Gabor M, Viney K, Quinn H, Janover O, McCready M, Heller J.In November 2014, New South Wales Health was notified of a cluster of respiratory illness in a veterinary school. Active case finding identified another case at a local equine stud. All cases had exposure to the equine fetal membranes of Mare A. This tissue subsequently tested positive for Chlamydia psittaci using quantitative real-time polymerase chain reaction. We conducted a cohort study of the university and stud farm staff to determine risk factors for disease. Nine people were exposed to the fetal membranes of Mare A. Of these, five cases of psittacosis were identified. Two required hosp...
Price J, Catriona S, Welsh EM, Waran NK.To develop a method for objective assessment of equine post-operative pain. Methods: Prospective nonblinded clinical study. Methods: Twelve adult horses: Group 1 (G1, n = 6), admitted for arthroscopy (under general anaesthesia, with multimodal analgesia); Group 2 (G2, n = 6), 'pain free' controls. Methods: Horses were filmed continuously (CVI, time-lapse video recorder) over 72 hours, from 24 hours pre-surgery (PS) to 48 hours post-recovery (PR) (G1), and over 24 hours (G2). Activity budgets were determined from 24 to 0 hours PS, 0-24 and 24-48 hours PR (G1) and for 24 hours (G2). Using direct...
Gálvez N, Fernández B, Sánchez P, Cuesta R, Ceolín M, Clemente-León M, Trasobares S, López-Haro M, Calvino JJ, Stéphan O, Domínguez-Vera JM.Transmission Electron Microscopy (TEM), X-ray Absorption Near Edge Spectroscopy (XANES), Electron Energy-Loss Spectroscopy (EELS), Small-Angle X-ray Scattering (SAXS), and SQUID magnetic studies were performed in a batch of horse spleen ferritins from which iron had been gradually removed, yielding samples containing 2200, 1200, 500, and 200 iron atoms. Taken together, findings obtained demonstrate that the ferritin iron core consists of a polyphasic structure (ferrihydrite, magnetite, hematite) and that the proportion of phases is modified by iron removal. Thus, the relative amount of magneti...
Yamashita K, Tsubakishita S, Futaok S, Ueda I, Hamaguchi H, Seno T, Katoh S, Izumisawa Y, Kotani T, Muir WW.The cardiovascular effects of medetomidine, detomidine, and xylazine in horses were studied. Fifteen horses, whose right carotid arteries had previously been surgically raised to a subcutaneous position during general anesthesia were used. Five horses each were given the following 8 treatments: an intravenous injection of 4 doses of medetomidine (3, 5, 7.5, and 10 microg/kg), 3 doses of detomidine (10, 20, and 40 microg/kg), and one dose of xylazine (1 mg/kg). Heart rate decreased, but not statistically significant. Atrio-ventricular block was observed following all treatments and prolonged wi...
Ginther OJ, Gastal EL, Gastal MO, Bergfelt DR, Baerwald AR, Pierson RA.Deviation in growth rates of the follicles of the ovulatory wave begins at the end of a common growth phase and is characterized by continued growth of the developing dominant follicle (F1) and regression of the largest subordinate follicle (F2). Follicle diameters during an interovulatory interval were compared between 30 mares and 30 women, using similar methods for collecting and analyzing data. Follicles were tracked and measured daily by ultrasonography. Diameter at follicle emergence (mares, 13 mm; women, 6 mm) and the required minimal attained diameter for assessment of follicles (mares...
Nielsen MK, Vidyashankar AN, Andersen UV, Delisi K, Pilegaard K, Kaplan RM.Fecal analyses are becoming increasingly important for equine establishments as a means of parasite surveillance and detection of anthelmintic resistance. Although several studies have evaluated various egg counting techniques, little is known about the quantitative effects of pre-analytic factors such as collection and storage of fecal samples. This study evaluated the effects of storage temperature, storage time and airtight versus open-air storage on fecal egg counts. The experimental protocols were replicated in two study locations: Copenhagen, Denmark and Athens, Georgia, USA. In both loc...
Nielsen MK, Vidyashankar AN, Olsen SN, Monrad J, Thamsborg SM.Nematodes belonging to the order Strongylida are ubiquitous in grazing horses, and the large strongyle Strongylus vulgaris is considered the most pathogenic. This parasite was originally described widely prevalent in equine establishments, but decades of frequent anthelmintic treatment appears to have reduced the prevalence dramatically. Increasing levels of anthelmintic resistance in cyathostomin parasites have led to implementation of selective therapy to reduce further development of resistance. It has been hypothesized that S. vulgaris could reoccur under these less intensive treatment cir...
Perkins GA, den Bakker HC, Burton AJ, Erb HN, McDonough SP, McDonough PL, Parker J, Rosenthal RL, Wiedmann M, Dowd SE, Simpson KW.Little is known about the gastric mucosal microbiota in healthy horses, and its role in gastric disease has not been critically examined. The present study used a combination of 16S rRNA bacterial tag-encoded pyrosequencing (bTEFAP) and fluorescence in situ hybridization (FISH) to characterize the composition and spatial distribution of selected gastric mucosal microbiota of healthy horses. Biopsy specimens of the squamous, glandular, antral, and any ulcerated mucosa were obtained from 6 healthy horses by gastroscopy and from 3 horses immediately postmortem. Pyrosequencing was performed on bio...
Yuki N, Shimazaki T, Kushiro A, Watanabe K, Uchida K, Yuyama T, Morotomi M.Selective adhesion to only certain epithelia is particularly common among the bacterial members of the indigenous microflora of mammals. We have found that the stratified squamous epithelium of the nonsecreting area of horse stomach is colonized by gram-positive rods. The microscopic features of a dense layer of these bacteria on the epithelium were found to be similar to those reported in mice, rats, and swine. Adhering microorganisms were isolated and identified as Lactobacillus salivarius, L. crispatus, L. reuteri, and L. agilis by DNA-DNA hybridization and 16S rRNA gene sequencing techniqu...
Kuwahara M, Hashimoto S, Ishii K, Yagi Y, Hada T, Hiraga A, Kai M, Kubo K, Oki H, Tsubone H, Sugano S.We studied power spectral analysis of heart rate (HR) variability in the horse, with the hypothesis that the quantitative information provided by the spectral analysis of HR variability reflects the interaction between sympathetic and parasympathetic regulatory activities. For this purpose, electrocardiogram, blood pressure (BP) and respiratory (Resp) waveform were simultaneously recorded from Thoroughbred horses (3-5 years old) and analyzed by power spectrum. There were two major spectral components at low-frequency (LF) and high-frequency (HF) bands for HR variability. The peak of Resp varia...
Campbell AJ, Gasser RB, Chilton NB.In the current study, molecular techniques were evaluated for the species identification of individual strongyle eggs. Adult worms of Strongylus edentatus, S. equinus and S. vulgaris were collected at necropsy from horses from Australia and the U.S.A. Genomic DNA was isolated and a ribosomal transcribed spacer (ITS-2) amplified and sequenced using polymerase chain reaction (PCR) techniques. The length of the ITS-2 sequence of S. edentatus, S. equinus and S. vulgaris ranged between 217 and 235 nucleotides. Extensive sequence analysis demonstrated a low degree (0-0.9%) of intraspecific variation...
Schauer SN, Sontakke SD, Watson ED, Esteves CL, Donadeu FX.Previous evidence from in vitro studies suggests specific roles for a subset of miRNAs, including miR-21, miR-23a, miR-145, miR-503, miR-224, miR-383, miR-378, miR-132, and miR-212, in regulating ovarian follicle development. The objective of this study was to determine changes in the levels of these miRNAs in relation to follicle selection, maturation, and ovulation in the monovular equine ovary. In Experiment 1, follicular fluid was aspirated during ovulatory cycles from the dominant (DO) and largest subordinate (S) follicles of an ovulatory wave and the dominant (DA) follicle of a mid-cycle...
Nunamaker DM, Butterweck DM, Provost MT.The North American Thoroughbred racehorse was chosen as a model to study the pathogenesis of fatigue failure of bone. This species has a high incidence of spontaneous fatigue failure of bone (bucked shins) during its early training. In vivo strain gauge studies of the third metacarpal bone of four young racehorses running at racing speeds showed high principal compressive strains [-4,841 +/- 572 (SD) microstrain] while two older horses had lower principal compressive strains (-3,317 microstrain measured at racing speed, -3,250 microstrain extrapolated from a slower speed run). Previously repor...
Wagner PD, Gillespie JR, Landgren GL, Fedde MR, Jones BW, DeBowes RM, Pieschl RL, Erickson HH.Arterial hypoxemia has been reported in horses during heavy exercise, but its mechanism has not been determined. With the use of the multiple inert gas elimination technique, we studied five horses, each on two separate occasions, to determine the physiological basis of the hypoxemia that developed during horizontal treadmill exercise at speeds of 4, 10, 12, and 13-14 m/s. Mean, blood temperature-corrected, arterial PO2 fell from 89.4 Torr at rest to 80.7 and 72.1 Torr at 12 and 13-14 m/s, respectively, whereas corresponding PaCO2 values were 40.3, 40.3, and 39.2 Torr. Alveolar-arterial PO2 di...
Burrell MH, Wood JL, Whitwell KE, Chanter N, Mackintosh ME, Mumford JA.A longitudinal study of respiratory disease in racehorses was carried out to assess its relative associations with different infectious agents and to examine any role that the environmental conditions might play. The relationships between coughing, nasal discharge, pyrexia and lower respiratory tract disease were also examined to provide information for improving clinical diagnosis, particularly of disease of the lower respiratory tract. Lower airway disease was closely associated with infection with Streptococcus zooepidemicus. It was also found that equine herpesvirus seroconversions and S p...
Maury W.In vivo, equine infectious anemia virus (EIAV) replicates in tissues rich in macrophages, and it is widely believed that the tissue macrophage is the principal, if not sole, cell within the host that replicates virus. No viral replication has been detected in circulating peripheral blood monocytes. However, proviral DNA can be detected in these cells, and monocytes may serve as a reservoir for the virus. In this study, an in vitro model was developed to clarify the role of monocyte maturation in regulating EIAV expression. Freshly isolated, nonadherent equine peripheral blood monocytes were in...
Carpenter S, Evans LH, Sevoian M, Chesebro B.Equine infectious anemia virus was isolated from peripheral blood leukocytes collected during two early febrile cycles of an experimentally infected horse. RNase T1-resistant oligonucleotide fingerprint analyses indicated that the nucleotide sequences of the isolates differed by approximately 0.25% and that the differences appeared randomly distributed throughout the genome. Serum collected in the interval between virus isolations was able to distinguish the isolates by membrane immunofluorescence on live cells. However, no neutralizing antibody was detected in the interval between virus isola...
Naskou MC, Sumner SM, Chocallo A, Kemelmakher H, Thoresen M, Copland I, Galipeau J, Peroni JF.Mesenchymal stem cells (MSCs) produced for clinical purposes rely on culture media containing fetal bovine serum (FBS) which is xenogeneic and has the potential to significantly alter the MSC phenotype, rendering these cells immunogenic. As a result of bovine-derived exogenous proteins expressed on the cell surface, MSCs may be recognized by the host immune system as non-self and be rejected. Platelet lysate (PL) may obviate some of these concerns and shows promising results in human medicine as a possible alternative to FBS. Our goal was to evaluate the use of equine platelet lysate (ePL) poo...
