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.
Gandini M, Giusto G.Most studies on colic surgery outcome focus on short-term survival and complications. Long-term outcomes, particularly post-discharge morbidity, are poorly characterised despite their relevance. No standardised system has previously integrated both short- and long-term postoperative complications with survival outcomes. Therefore, this study aimed to evaluate long-term survival and morbidity in horses after colic surgery using the equine postoperative complication score (EPOCS), and to assess the association between complications and survival. Methods: The medical records of horses undergoing ...
Friend MM, McGaffigan EM, Hall SM, Staniar WB, Smarsh DN.Equine blood samples are often collected in uncontrolled, distant environments and stored for later analysis. Objective: This study aimed to determine how sample storage methods influence complete blood count (CBC) parameters, hypothesizing that temperature and time elapsed from collection to analysis would affect CBC parameters. Methods: Blood samples were collected from 10 healthy Quarter Horse mares (age: 13 ± 4.5 years old) and stored in EDTA tubes at room temperature (22°C), above ice (8°C), refrigerated (4°C), or in contact with ice (2°C). The IDEXX ProcyteDx was used to obtain CBCs...
Cramp P.From average school reports to a surgical residency in the USA and running a 17-vet practice, this is the unplanned route Phil Cramp took to finding a career he loves.
Korac L, St George L, MacNicol J, McCrae P, Jung L, Golestani N, Karrow N, Cánovas A, Pearson W.Low-dose intra-articular injection of recombinant equine interleukin-1β (reIL-1β) may offer a useful model for studying early onset or subclinical joint inflammation in horses. This pilot study aimed to determine the lowest intra-articular dose of reIL-1β required to produce biochemical evidence of synovitis, and to correlate synovitis biomarkers with functional, upper-body asymmetry parameters. Saline (control) and 50, and 75 ng reIL-1β were injected into the left or right intercarpal joint of three ( = 3) horses in a three-way crossover design. Synovial fluid was collected by aseptic art...
Key K, Kirkegaard J, Berg K, Andresen KR, Skov Hansen S.A handheld smartphone-based computer vision algorithm (RealHorse® [RH]) offers accessible alternatives for equine gait analysis but requires validation against a gold-standard three-dimensional multicamera optical motion capture system (Qualisys® [QS]). Objective: To evaluate the accuracy and precision of RH in measuring vertical displacement signals (VDS) at the eye, withers, back and croup in horses trotting on a straight line and on a circle. Methods: Cross-sectional comparative validation study of a markerless computer vision algorithm. Methods: Fifty-nine horses were recorded while trot...
Rollet M, Flyps J, Vernemmen I, van Loon G, Schauvliege S.Hyperkalaemia is an uncommon complication of general anaesthesia in healthy horses. This case report describes the occurrence of life-threatening acute hyperkalaemia in a 13-year-old, female French Trotter anaesthetised for experimental right and left atrial 3D electro-anatomical mapping. Intra-operative development of hyperkalaemia (7.55 mmol/L) (Ref. 3.00-4.00 mmol/L) with atrial standstill on ECG necessitated transvenous ventricular pacing while initial treatment with insulin and glucose was initiated. Plasma potassium levels continued to increase (8.00 mmol/L) prompting adjunctive tr...
Mlyneková E, Zaťko S, Halo M, Imrich I, Halo M.This study aimed to examine the seasonal dynamics of non-structural carbohydrates in pasture and their relationship to metabolic indicators in horses with a history of laminitis. Thirty Hucul mares were divided into a laminitis group (LG, = 15) and a control group (CG, = 15). Insulin, glucose, fructosamines concentrations and body weight were monitored during four sampling periods (S0-S3), while pasture variables were analyzed during three periods (S1-S3). The concentration of water-soluble carbohydrates was highest in May (126.8 g/kg DM) and measured lower in October (57.9 g/kg DM), while s...
Ferreira C, Palhares MS, de Melo UP, Leme FOP, Maranhão RPA, Garcia HC, Gheller VA.Starvation and nutritional support clinically influence horses, particularly during the treatment of gastrointestinal diseases and post-surgical recovery. In this study, we aimed to evaluate the effects of different nutritional strategies on the endocrine response of horses subjected to exploratory laparotomy followed by food deprivation. Sixteen healthy adult horses were randomly allocated into four groups (n=4) based on treatments: enteral fluid therapy without (ENTFL) or with glutamine (ENTGL), and parenteral fluid therapy with glucose (PARFL) or total parenteral nutrition with glutamine (P...
Morales CJ, Sykes BW, McKemie DS, Kass PH, Knych HK.Current treatment options for equine gastric ulcer syndrome (EGUS), such as omeprazole-a proton pump inhibitor (PPI)-have notable limitations, including the need for administration on an empty stomach. Potassium-competitive acid blockers (P-CABs), such as vonoprazan, are a newer class of acid suppressants that offer several advantages over PPIs in humans and may provide similar benefits in horses. Objective: To describe the pharmacokinetics and effect of a single oral dose of vonoprazan on intragastric pH in horses. We hypothesised that vonoprazan would follow linear kinetics across the doses ...
Valenchon M, Reigner F, Lefort G, Adriaensen H, Gesbert A, Barrière P, Gaude Y, Elleboudt F, Lévy I, Ducluzeau C, Dupont J, Lainé AL, Uszynski I....Social interactions shape both the physiological and behavioural development of offspring, and poor care/early caregiver loss is known to promote adverse outcomes during infancy in both animals and humans. How affiliative behaviours impact the future development of offspring remains an open question. Here, we used Equus caballus (domestic horse) as a model to investigate this question. By coupling magnetic resonance imaging, longitudinal biobehavioural assessments and advanced multivariate statistical modelling, we found that prolonged maternal presence during infancy promotes the maturation o...
Ventura Lopes Carvalho B, Neves de Souza MC, Souza Moreira N, Parisi Marliere J, Mesquita Mota JV, Drumond Bento L, de Castro Benitez A, Avanza MFB....Two routes of administration for electrolyte solutions are commonly used in horses with fluid, electrolyte, and acid-base imbalances: intravenous and nasogastric. Despite the frequent use of these routes, there are situations in which they cannot be applied. In such cases, intracecal fluid therapy represents a viable alternative, as this route enables the administration of enteral electrolyte solutions even in animals lacking normal anterior gastrointestinal function. This study aimed to evaluate the effects of a neutral hypotonic enteral electrolyte solution administered intracecally at two d...
Shahid MA, Guitart AS, Bertin FR, Simon O, Ceusters J, Serteyn D, Whitworth DJ.A minimally invasive microbiopsy-based method for the isolation of mesenchymal stem cells (MSCs) from equine skeletal muscle (M-MSCs) provides a readily accessible source of MSCs for clinical applications. We examined the expression of genes associated with immunomodulation and anti-inflammatory pathways, in addition to those of growth factors and the major histocompatibility complex (MHC) molecules I and II, at constitutive levels and after priming with inflammatory cytokines, an immunostimulant, and heat-shocking. While there was notable variation between the M-MSCs from each of the horses i...
Medina-Bautista F, Morgaz J, Quirós-Carmona S, Caravaca-Paredes ME, Navarrete-Calvo R, Medina ALS, Gómez-Villamandos R, Granados MDM.Standing sedation in horses provides immobilization and analgesia for surgery while avoiding the high risks of general anesthesia. Ketamine at subanesthetic doses may enhance sedation and reduce xylazine requirements, but evidence in clinical settings is limited. In a randomized blinded trial, we evaluated whether adding a low-dose ketamine infusion could reduce the xylazine dose required for effective sedation during standing ventriculocordectomy and laryngoplasty. Fifty-one horses were randomly assigned to sedation with xylazine alone (SX group) or xylazine plus ketamine (KX group) in a cont...
Jafari H, Abebe BK, Cong L, Ahmed Z, Zhaofei W, Sun M, Muhatai G, Chuzhao L, Dang R.The domestication and selective breeding of horses have profoundly influenced the emergence of adaptive traits and stress resistance mechanisms, shaping modern equine populations. This comprehensive review examines the genomic foundations of these traits, emphasizing recent advancements in high-throughput sequencing technologies and bioinformatics. These tools have elucidated the genetic underpinnings of key characteristics such as endurance, speed, metabolic efficiency, and disease resistance. Importantly, the review identifies and connects gene variants associated with thermoregulation, immu...
Alves NC, Freitas MM, Faria JRD, Horta CL, Martins-Filho OA, Araújo MSS, Costa GMJ, Costa EA, de Almeida FRL, Amaral PHR, Pérez JCG, Lana ÂQ....Niacin acts as an antioxidant that protects cells from oxidative damage. This study evaluated the effects of adding niacin to the equine semen freezing extender on sperm quality and gene expression after cryopreservation. Ejaculates from ten stallions were frozen using the INRA 96 extender (control) or extenders supplemented with 10- and 20-mM niacin. After thawing, sperm were analysed for motility, kinematics, viability, membrane integrity, mitochondrial potential, lipid peroxidation, nitrite, hydrogen peroxide, malondialdehyde and reactive oxygen species (ROS) concentrations, DNA integrity, ...
Kirmse L, Thieme K, Doherr MG, Eule JC.To evaluate different laboratory procedures for determining the etiologic diagnosis of equine recurrent uveitis regarding intraocular infection with Leptospira spp. and to establish a diagnostic guideline. Methods: Eighty horses with a history of ERU were ophthalmologically examined. Serum and aqueous humor were collected. Total protein, albumin level, and MAT against Leptospira spp. were evaluated on serum and aqueous humor. PCR for Leptospira spp., EHV-1 and -4 was performed on aqueous humor. Goldmann-Witmer coefficient (GWC) and C-value (CC) were calculated based on MAT. In 42 cases, an add...
Mendoza Flores JE, Terrazas A, Lara Sagahon AV, Aleman M.Parasympathetic tone activity (PTA) and its association with behavior in conscious versus anesthesia in horses are unknown. Objective: To study PTA, heart rate (HR), minimum alveolar concentration (MAC), and mean arterial pressure (MAP) during castration under anesthesia. To study PTA, HR, Horse Grimace Scale (HGS), locomotor activity (LA), and behavior in conscious horses before and after castration. Methods: Pilot study including seven healthy adult horses. After habituation (days 1, 2, and 3), PTAm, HR, HGS, LA, and behavior were investigated during pre-surgery (days 4-, 5-, and one-hour pr...
Carvalho BVL, de Souza MCN, Avanza MFB, Teixeira RBC, Silva JRB, da Silva Cardoso T, Novais LGES, de Oliveira Monteiro FD, Viana RB, Monteiro BM....Access to the equine cecum is required for various therapeutic and experimental procedures, including decompression, fluid therapy, and transfaunation. Traditional approaches via laparotomy are highly invasive. This study aimed to describe a minimally invasive, laparoscopically assisted technique for cecal cannulation in standing horses. Unassigned: Seven horses underwent the procedure under sedation and paravertebral anesthesia. Two right flank accesses were created: a 10-mm laparoscopic port for visualization and a 2-cm minilaparotomy for cecal exteriorization. A Foley catheter was inserted ...
Dersch K, Kreuder A, Wang C, Troy J.Surgical site infections (SSI) are a common postoperative complication of equine orthopedic surgery and often increase morbidity and mortality. Objective: This study aimed to determine if covering surgical instruments during surgery decreased bacterial environmental air contamination during early opening of surgical packs (EOSP). The authors hypothesized that covering instruments with sterile surgical towels would reduce the total number of bacterial colonies to which the instruments were exposed. Methods: Blood agar plates (BAP) were allocated into two groups (non-covered vs. covered with a s...
Vallejo-Soto P, Dorado J, Herrera-García R, Álvarez-Delgado C, Gómez-Laguna J, Santiago Á, Manrique M, González Ariza A, León Jurado JM....Assisted reproductive techniques are often extrapolated from horses to donkeys, despite poorer fertility outcomes in jennies. This issue has been attributed to unknown uterine species-specific differences. This study compared, through histomorphometry, the endometrium of jennies and mares. Endometrial biopsies (N = 12) were taken from reproductively sound jennies (n = 6) and mares (n = 6) in estrus. Histomorphometric analysis evaluated luminal (LE, µm) and glandular epithelium height (GE, µm), glandular lumen diameter (LD, µm), glandular area (GA, µm), the number of glands (#G), and glandu...
Choi Y, Jung Y, Wickens CL, Yoon M.Horses are social animals, with early life experiences playing a crucial role in their physiological and behavioral development. This study explored the influence of herd dynamics and foundational training on behavioral and hormonal changes in weaned foals. We examined 13 six-month-old Quarter Horse foals over a three-month training period, performing behavioral observations, temperament assessments, and hormone analyses at the start, midpoint, and end of the training. The results indicated that affiliative behaviors decreased significantly, while agonistic behaviors first increased and then d...
Cantarelli C, Cribb NC, Delli-Rocili M, Brisson B, Zur Linden A, Caswell JL.Long-term assessment of nephrosplenic space (NSS) closure and comparisons with ultrasonography and rectal palpation are lacking. The objective was to evaluate NSS closure in 12 research horses 5 y following laparoscopic ablation, using a novel adhesion scoring system, and to assess whether rectal examination and ultrasonographic findings could predict adhesion adequacy. The NSS was examined rectal palpation and ultrasonography prior to surgery, and at 30 d and 5 y after surgery. Ultrasonographic measurements of the distances between the renal fascia and spleen were recorded. The NSS adhesions...
Jastrzębska E, Dobbek D, Pawłowska A.Back pain in horses is a frequent musculoskeletal issue that affects performance and welfare. Magnetotherapy has been proposed as a complementary, non-invasive treatment to reduce pain and support soft tissue recovery, but studies in horses remain limited. This pilot study aimed to evaluate the effects of low-frequency pulsed magnetic field therapy on horses with hypersensitivity to palpation along the longissimus dorsi muscle. Four recreational horses participated in a 10-session magnetotherapy program, with changes assessed using palpation, neck flexibility tests, heart rate measurements and...
Repciuc CC, Oros NV, Mureșan ȘMC, Sevastre B, Joaquim JGF, Oana LI.Limb wounds in horses represent a significant therapeutic challenge due to poor vascularization, reduced skin elasticity, and high risk of complications such as exuberant granulation tissue. Conventional treatments sometimes fail to provide satisfactory healing outcomes, leading to prolonged recovery and increased costs. This study aimed to evaluate the efficacy of topical ozone therapy using the bagging method in promoting the epithelialization and contraction of chronic distal limb wounds in horses refractory to conventional management. Eight horses, aged 3-21 years, with chronic wounds aver...
Busechian S, Di Salvo A, Orvieto S, Rueca F, Villella C, Sollevanti G, Pieramati C, Nisi I, Della Rocca G.Equine Gastric Ulcer Syndrome (EGUS) is a worldwide disease described in different categories of animals. A causal relationship between exercise and EGUS has been suggested, attributed to stress as well as physiological changes in the position of abdominal organs, especially during trot and gallop. EGUS can influence athletic fitness, as has been described in various papers on racehorses. The aim of this work was to determine if gastric ulcer healing is associated with changes in selected fitness parameters (i.e., speed, heart rate during exercise and recovery, stride length and frequency) in ...
Bourassi S, Jack H, Florczyk A.A 4-year-old Arabian cross paint mare was referred for evaluation of chronic mucopurulent discharge and epiphora of the left eye. Ophthalmic and radiographic evaluations confirmed distal nasolacrimal duct atresia with absence of the nasolacrimal orifice. Initial minimally invasive treatments, including guidewire-assisted catheterization and diode laser photoablation, were unsuccessful. Definitive treatment was achieved using a Fogarty arterial embolectomy catheter under standing sedation. Controlled balloon inflation and deflation enabled progressive dilation of the obstructed duct, and a surg...
Manolăchescu D, Tripon M, Crecan C, Tătaru M, Papuc I.Emotional contagion in human-horse interactions has been widely studied; however, the role of body language in stress transfer remains insufficiently explored. Unassigned: This study examines whether human emotional states, particularly stress and anxiety, influence horses and whether the transmission occurs primarily through body language. Unassigned: A repeated-measures within-subjects design was used. The order of interaction styles was randomized across subjects during 33 HCIs. Participants were categorized as high-anxiety (HA) or low-anxiety (LA) based on State Anxiety Scale scores and he...
Almaqhawi AA, El-Jalii IM, Al-Sabi MNS, Al-Ali A, Khalid AM, Abduljawad M, Shawaf T.Equine babesiosis is a widespread protozoan disease in Saudi Arabia. The most common finding of clinical babesiosis is splenomegaly, which can be detected using non-invasive splenic ultrasonography. Unassigned: This study aimed to investigate changes in the spleen size in horses infected with babesiosis using ultrasonography before and after treatment. Unassigned: This study employed 15 male and female Arabian horses. Each animal was examined clinically for clinical signs, and blood samples were collected in plain tubes to detect antibodies against . The spleens of healthy and affected horses ...
Bergeler J, Liske-Schmitz A, Schmitz T, de Camp NV.The First Night Effect is a phenomenon whereby sleep duration and quality are compromised in unfamiliar environments or situations. Horses are often transported to new locations, such as sporting events. We wanted to know if the First Night Effect is also detectable in horses in two different populations. To investigate this, we compared five horses from a professional sports horse barn that are regularly used in competitions, with six horses from a breeding barn, that are less frequently transferred to unfamiliar places. Despite the significant differences observed in electroencephalography (...
Balazs EA, Denlinger JL.Viscosupplementation is a new medical concept that has as its therapeutic goal the restoration of rheological homeostasis in pathological structures such as osteoarthritic joints. When the normal viscoelasticity of a solid tissue compartment or the elastoviscosity of a liquid tissue compartment is decreased under pathological conditions, normal function and regenerative processes are impaired. By introducing viscosupplementary devices, the normal rheological state of such compartments is restored or augmented. These devices stay in the tissue compartment for various periods of time, depending ...
Science (New York, N.Y.)August 26, 1983
Volume 221, Issue 4613 823-828 doi: 10.1126/science.6308762
Campbell WC, Fisher MH, Stapley EO, Albers-Schönberg G, Jacob TA.Ivermectin is the 22,23-dihydro derivative of avermectin B1, a macrocyclic lactone produced by an actinomycete, Streptomyces avermitilis. It is active at extremely low dosage against a wide variety of nematode and arthropod parasites, apparently by virtue of its action on the mediation of neurotransmission by gamma-aminobutyric acid. It is now in commercial use in various countries for the treatment and control of parasites in cattle, horses, and sheep, and is expected to become available for use in swine and dogs. Since studies with the drug in man are in a preliminary stage, it is not yet kn...
Li VL, He Y, Contrepois K, Liu H, Kim JT, Wiggenhorn AL, Tanzo JT, Tung AS, Lyu X, Zushin PH, Jansen RS, Michael B, Loh KY, Yang AC, Carl CS....Exercise confers protection against obesity, type 2 diabetes and other cardiometabolic diseases1-5. However, the molecular and cellular mechanisms that mediate the metabolic benefits of physical activity remain unclear6. Here we show that exercise stimulates the production of N-lactoyl-phenylalanine (Lac-Phe), a blood-borne signalling metabolite that suppresses feeding and obesity. The biosynthesis of Lac-Phe from lactate and phenylalanine occurs in CNDP2+ cells, including macrophages, monocytes and other immune and epithelial cells localized to diverse organs. In diet-induced obese mice,...
Carroll CL, Huntington PJ.Three hundred and seventy two horses of varying breeds, height and fatness were weighed and measured for height at the withers. They were assessed for condition score by adaptation of a previously published method. The heart girth and length of 281 of the horses were also measured. Weight of horses was highly correlated (P less than 0.001) with height (r2 = 0.62), condition score (r2 = 0.22) and girth2 x length (r2 = 0.90). Nomograms were constructed to predict weight from height and condition score, and girth and length measurements. Weight can also be accurately estimated from the formula: (...
Godwin EE, Young NJ, Dudhia J, Beamish IC, Smith RK.Mesenchymal stem (progenitor; stromal) cell (MSC) therapy has gained popularity for the treatment of equine tendon injuries but without reports of long-term follow-up. Objective: To evaluate the safety and reinjury rate of racehorses after intralesional MSC injection in a large study of naturally occurring superficial digital flexor tendinopathy and to compare these data with those published for other treatments. Methods: Safety was assessed clinically, ultrasonographically, scintigraphically and histologically in a cohort of treated cases: 141 client-owned treated racehorses followed-up for a...
Schubert M, Jónsson H, Chang D, Der Sarkissian C, Ermini L, Ginolhac A, Albrechtsen A, Dupanloup I, Foucal A, Petersen B, Fumagalli M, Raghavan M....The domestication of the horse ∼ 5.5 kya and the emergence of mounted riding, chariotry, and cavalry dramatically transformed human civilization. However, the genetics underlying horse domestication are difficult to reconstruct, given the near extinction of wild horses. We therefore sequenced two ancient horse genomes from Taymyr, Russia (at 7.4- and 24.3-fold coverage), both predating the earliest archeological evidence of domestication. We compared these genomes with genomes of domesticated horses and the wild Przewalski's horse and found genetic structure within Eurasia in the Late Pleist...
Selvey LA, Wells RM, McCormack JG, Ansford AJ, Murray K, Rogers RJ, Lavercombe PS, Selleck P, Sheridan JW.To describe the clinical and epidemiological features of an outbreak of a viral infection affecting humans and horses. Methods: Stables in Hendra, a suburb of Brisbane. Methods: Affected horses and humans, and at-risk human contacts. Results: A pregnant mare died two days after arrival from a paddock elsewhere in Brisbane. Eight to 11 days later, illness (depression, anorexia, fever, dyspnoea, ataxia, tachycardia, tachypnoea and nasal discharge) was reported among 17 other horses from the same or an adjoining stable. Fourteen horses died or were put down. Five and six days after the index mare...
Furet JP, Firmesse O, Gourmelon M, Bridonneau C, Tap J, Mondot S, Doré J, Corthier G.Pollution of the environment by human and animal faecal pollution affects the safety of shellfish, drinking water and recreational beaches. To pinpoint the origin of contaminations, it is essential to define the differences between human microbiota and that of farm animals. A strategy based on real-time quantitative PCR (qPCR) assays was therefore developed and applied to compare the composition of intestinal microbiota of these two groups. Primers were designed to quantify the 16S rRNA gene from dominant and subdominant bacterial groups. TaqMan probes were defined for the qPCR technique used ...
Ching PK, de los Reyes VC, Sucaldito MN, Tayag E, Columna-Vingno AB, Malbas FF, Bolo GC, Sejvar JJ, Eagles D, Playford G, Dueger E, Kaku Y....During 2014, henipavirus infection caused severe illness among humans and horses in southern Philippines; fatality rates among humans were high. Horse-to-human and human-to-human transmission occurred. The most likely source of horse infection was fruit bats. Ongoing surveillance is needed for rapid diagnosis, risk factor investigation, control measure implementation, and further virus characterization.
Pawelek KA, Huynh GT, Quinlivan M, Cullinane A, Rong L, Perelson AS.Influenza virus infection remains a public health problem worldwide. The mechanisms underlying viral control during an uncomplicated influenza virus infection are not fully understood. Here, we developed a mathematical model including both innate and adaptive immune responses to study the within-host dynamics of equine influenza virus infection in horses. By comparing modeling predictions with both interferon and viral kinetic data, we examined the relative roles of target cell availability, and innate and adaptive immune responses in controlling the virus. Our results show that the rapid and ...
Webb JG, Chandavimol M, Thompson CR, Ricci DR, Carere RG, Munt BI, Buller CE, Pasupati S, Lichtenstein S.Percutaneous aortic valve implantation by an antegrade transvenous approach has been described but is problematic. Retrograde prosthetic aortic valve implantation via the femoral artery has potential advantages. Percutaneous prosthetic aortic valve implantation via the femoral arterial approach is described and the initial experience reported. Results: The valve prosthesis is constructed from a stainless steel stent with an attached trileaflet equine pericardial valve and a fabric cuff. After routine aortic balloon valvuloplasty, a 22F or 24F sheath is advanced from the femoral artery to the a...
Ito S, Wakamatsu K.The color of hair, skin, and eyes in animals mainly depends on the quantity, quality, and distribution of the pigment melanin, which occurs in two types: black to brown eumelanin and yellow to reddish pheomelanin. Microanalytical methods to quantify the amounts of eumelanin and pheomelanin in biological materials were developed in 1985. The methods are based on the chemical degradation of eumelanin to pyrrole-2,3,5-tricarboxylic acid and of pheomelanin to aminohydroxyphenylalanine isomers, which can be analyzed and quantitated by high performance liquid chromatography. This review summarizes a...
Woldehiwet Z.Anaplasma phagocytophilum is the recently designated name replacing three species of granulocytic bacteria, Ehrlichia phagocytophila, Ehrlichia equi and the agent of human granulocytic ehrlichiosis, after the recent reorganization of the families Rickettsiaceae and Anaplasmataceae in the order Rickettsiales. Tick-borne fever (TBF), which is caused by the prototype of A. phagocytophilum, was first described in 1932 in Scotland. A similar disease caused by a related granulocytic agent was first described in horses in the USA in 1969; this was followed by the description of two distinct granulocy...
McIlwraith CW, Frisbie DD, Kawcak CE.Osteoarthritis (OA) is an important cause of pain, disability and economic loss in humans, and is similarly important in the horse. Recent knowledge on post-traumatic OA has suggested opportunities for early intervention, but it is difficult to identify the appropriate time of these interventions. The horse provides two useful mechanisms to answer these questions: 1) extensive experience with clinical OA in horses; and 2) use of a consistently predictable model of OA that can help study early pathobiological events, define targets for therapeutic intervention and then test these putative thera...
Calisher CH.Of more than 500 arboviruses recognized worldwide, 5 were first isolated in Canada and 58 were first isolated in the United States. Six of these viruses are human pathogens: western equine encephalitis (WEE) and eastern equine encephalitis (EEE) viruses (family Togaviridae, genus Alphavirus), St. Louis encephalitis (SLE) and Powassan (POW) viruses (Flaviviridae, Flavivirus), LaCrosse (LAC) virus (Bunyaviridae, Bunyavirus), and Colorado tick fever (CTF) virus (Reoviridae, Coltivirus). Their scientific histories, geographic distributions, virology, epidemiology, vectors, vertebrate hosts, transm...
Weaver SC, Salas R, Rico-Hesse R, Ludwig GV, Oberste MS, Boshell J, Tesh RB.Venezuelan equine encephalomyelitis (VEE) virus has caused periodic epidemics among human beings and equines in Latin America from the 1920s to the early 1970s. The first major outbreak since 1973 occurred in Venezuela and Colombia during 1995, and involved an estimated 75,000 to 100,000 people. We report an epidemiological and virological investigation of this epidemic. Methods: Virus isolates were made in cell culture from human serum, human throat swabs, and brain tissue from aborted and stillborn human fetuses, as well as from horse brain tissue and pooled mosquito collections. Human sera ...
Puffer BA, Parent LJ, Wills JW, Montelaro RC.We have previously demonstrated that the Gag p9 protein of equine infectious anemia virus (EIAV) is functionally homologous with Rous sarcoma virus (RSV) p2b and human immunodeficiency virus type 1 (HIV-1) p6 in providing a critical late assembly function in RSV Gag-mediated budding from transfected COS-1 cells (L. J. Parent et al., J. Virol. 69:5455-5460, 1995). In light of the absence of amino acid sequence homology between EIAV p9 and the functional homologs of RSV and HIV-1, we have now designed an EIAV Gag-mediated budding assay to define the late assembly (L) domain peptide sequences con...
Frisbie DD, Cross MW, McIlwraith CW.Histological measurements of the thickness of non-calcified and calcified cartilage, as well as the subchondral bone plate in five locations on the femoral trochlea and medial femoral condyles of species were used in preclinical studies of articular cartilage and compared to those of the human knee. Cadaver specimens were obtained of six human knees, as well as six equine, six goat, six dog, six sheep and six rabbit stifle joints (the animal equivalent of the human knee). Specimens were taken from the lateral trochlear ridge, medial trochlear ridge and medial femoral condyle. After histopathol...
Rosengren Pielberg G, Golovko A, Sundström E, Curik I, Lennartsson J, Seltenhammer MH, Druml T, Binns M, Fitzsimmons C, Lindgren G, Sandberg K....In horses, graying with age is an autosomal dominant trait associated with a high incidence of melanoma and vitiligo-like depigmentation. Here we show that the Gray phenotype is caused by a 4.6-kb duplication in intron 6 of STX17 (syntaxin-17) that constitutes a cis-acting regulatory mutation. Both STX17 and the neighboring NR4A3 gene are overexpressed in melanomas from Gray horses. Gray horses carrying a loss-of-function mutation in ASIP (agouti signaling protein) had a higher incidence of melanoma, implying that increased melanocortin-1 receptor signaling promotes melanoma development in Gra...
Kalbfleisch TS, Rice ES, DePriest MS, Walenz BP, Hestand MS, Vermeesch JR, O Connell BL, Fiddes IT, Vershinina AO, Saremi NF, Petersen JL, Finno CJ....Recent advances in genomic sequencing technology and computational assembly methods have allowed scientists to improve reference genome assemblies in terms of contiguity and composition. EquCab2, a reference genome for the domestic horse, was released in 2007. Although of equal or better quality compared to other first-generation Sanger assemblies, it had many of the shortcomings common to them. In 2014, the equine genomics research community began a project to improve the reference sequence for the horse, building upon the solid foundation of EquCab2 and incorporating new short-read data, lon...
Chaucheyras-Durand F, Durand H.The use of probiotics for farm animals has increased considerably over the last 15 years. Probiotics are defined as live microorganisms which can confer a health benefit for the host when administered in appropriate and regular quantities. Once ingested, the probiotic microorganisms can modulate the balance and activities of the gastrointestinal microbiota, whose role is fundamental to gut homeostasis. It has been demonstrated that numerous factors, such as dietary and management constraints, can strongly affect the structure and activities of the gut microbial communities, leading to impaired...
Marasas WF, Kellerman TS, Gelderblom WC, Coetzer JA, Thiel PG, van der Lugt JJ.Each of two horses was dosed by stomach tube with culture material on maize of Fusarium moniliforme MRC 826. One horse developed severe hepatosis and mild oedema of the brain after 6 doses of 2.5 g of culture material/kg body mass/day in 7 days. The second horse, in a similar experiment but at a dosage rate of 1.25 g/kg/day, developed mild hepatosis and moderate oedema of the brain. In both animals the brain oedema was particularly noticeable in the medulla oblongata. The mycotoxin fumonisin B1 was extracted and purified from the culture material of F. moniliforme MRC, 826 which contained appr...
Ahern BJ, Parvizi J, Boston R, Schaer TP.Review the literature for single site cartilage defect research and evaluate the respective strengths and weaknesses of different preclinical animal models. Methods: A literature search for animal models evaluating single site cartilage defects was performed. Variables tabulated and analyzed included animal species, age and number, defect depth and diameter and study duration. Cluster analyses were then used to separate animals with only distal femoral defects into similar groups based on defect dimensions. Representative human studies were included allowing comparison of common clinical lesio...
Makvandi-Nejad S, Hoffman GE, Allen JJ, Chu E, Gu E, Chandler AM, Loredo AI, Bellone RR, Mezey JG, Brooks SA, Sutter NB.Horse body size varies greatly due to intense selection within each breed. American Miniatures are less than one meter tall at the withers while Shires and Percherons can exceed two meters. The genetic basis for this variation is not known. We hypothesize that the breed population structure of the horse should simplify efforts to identify genes controlling size. In support of this, here we show with genome-wide association scans (GWAS) that genetic variation at just four loci can explain the great majority of horse size variation. Unlike humans, which are naturally reproducing and possess many...
MacDonald GH, Johnston RE.The initial steps of Venezuelan equine encephalitis virus (VEE) spread from inoculation in the skin to the draining lymph node have been characterized. By using green fluorescent protein and immunocytochemistry, dendritic cells in the draining lymph node were determined to be the primary target of VEE infection in the first 48 h following inoculation. VEE viral replicon particles, which can undergo only one round of infection, identified Langerhans cells to be the initial set of cells infected by VEE directly following inoculation. These cells are resident dendritic cells in the skin, which mi...
Achilli A, Olivieri A, Soares P, Lancioni H, Hooshiar Kashani B, Perego UA, Nergadze SG, Carossa V, Santagostino M, Capomaccio S, Felicetti M....Archaeological and genetic evidence concerning the time and mode of wild horse (Equus ferus) domestication is still debated. High levels of genetic diversity in horse mtDNA have been detected when analyzing the control region; recurrent mutations, however, tend to blur the structure of the phylogenetic tree. Here, we brought the horse mtDNA phylogeny to the highest level of molecular resolution by analyzing 83 mitochondrial genomes from modern horses across Asia, Europe, the Middle East, and the Americas. Our data reveal 18 major haplogroups (A-R) with radiation times that are mostly confined ...
Petersen JL, Mickelson JR, Cothran EG, Andersson LS, Axelsson J, Bailey E, Bannasch D, Binns MM, Borges AS, Brama P, da Câmara Machado A, Distl O....Horses were domesticated from the Eurasian steppes 5,000-6,000 years ago. Since then, the use of horses for transportation, warfare, and agriculture, as well as selection for desired traits and fitness, has resulted in diverse populations distributed across the world, many of which have become or are in the process of becoming formally organized into closed, breeding populations (breeds). This report describes the use of a genome-wide set of autosomal SNPs and 814 horses from 36 breeds to provide the first detailed description of equine breed diversity. F(ST) calculations, parsimony, and dista...
Petersen JL, Mickelson JR, Rendahl AK, Valberg SJ, Andersson LS, Axelsson J, Bailey E, Bannasch D, Binns MM, Borges AS, Brama P, da Câmara Machado A....Intense selective pressures applied over short evolutionary time have resulted in homogeneity within, but substantial variation among, horse breeds. Utilizing this population structure, 744 individuals from 33 breeds, and a 54,000 SNP genotyping array, breed-specific targets of selection were identified using an F(ST)-based statistic calculated in 500-kb windows across the genome. A 5.5-Mb region of ECA18, in which the myostatin (MSTN) gene was centered, contained the highest signature of selection in both the Paint and Quarter Horse. Gene sequencing and histological analysis of gluteal muscle...
