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.
Söderroos D, Stefánsdóttir GJ, Ragnarsson S, Gunnarsson V, Jansson A.Weight carrying capacity is an important trait in riding horses and it may be associated with conformation. This study examined the physiological response to a ridden incremental weight carrying test in 16 adult Icelandic horses used for tour riding. Horses carried 20% (BWR20%), 25% (BWR25%), 30% (BWR30%) and 35% (BWR35%) of their body weight (BW) in tölt (~ 5.7 m/seconds, 640 m/step), and associations with body measurements and back conformation (score) were examined. Horses were divided into two groups (narrow or broad back) and body measurements were collected. Plasma lactate was analy...
Neudeck S, Sauter PK, Kutter APN, Steblaj B, Söbbeler FJ, Reiners J, Freise F, Gutiérrez Bautitsta AJ, Kästner SBR.Endotoxaemia is a significant cause of morbidity and mortality in equids due to perfusion impairment and possible destruction of the glycocalyx. To evaluate our hypothesis that endotoxaemia induces changes in global cardiovascular and haematologic parameters and compromises glycocalyx integrity, evidenced by an early rise in plasma shedding products. In vivo experiments METHODS: In a prospective, randomised, controlled experimental trial, endotoxaemia was induced with E. coli B55:O5 LPS 30 ng kg over 30 min IV in six healthy adult horses ventilated with oxygen supplemented with isoflurane. St...
Meistro F, Ralletti MV, Rinnovati R, Spadari A.Subtle locomotor asymmetries are common in horses and may go unnoticed during routine pre-race clinical inspections, particularly when based solely on subjective evaluation. This study aimed to describe vertical head and pelvic movement asymmetries in racehorses that passed official pre-race inspections at a traditional racing event. Twenty-four horses were analysed using a markerless AI-based gait analysis system while trotting in-hand and during lungeing in both directions. Asymmetry parameters (HDmin, HDmax, PDmin, and PDmax) were extracted from video recordings, with values ≥0.5 consider...
Walz KR, McCormick ME, Fedorka CE.Breed bias exists within many of the top disciplines of equestrian sport. Therefore, the objective of this study was to evaluate the influence of breed on performance at the CCI5*-L level of eventing. To do so, the results of all CCI5*-L events from 2014 to 2024 were assessed. Initially, Thoroughbreds were compared to all non-Thoroughbreds, and this was followed by assessing the ten primary breeds. Data included penalties accrued in dressage, cross country, show jumping, and overall. Additionally, the likelihood of completing each phase was assessed. It was found that Thoroughbreds accrued mor...
Simões J, Santos AM, Santos C, Silva AS, Vintém C, Fonseca J, Coelho C.Show jumping is a popular and complex equestrian modality practiced by a athletes of different levels. However, most studies focus on elite athletes. Objective: The aim of this work was to assess the effect of a show jumping test (SJT), designed for novice athletes, on the physiological biomarkers and energy indexes of a group of horses, bred and trained in Portugal. Methods: In this prospective cross-sectional study, thirteen horses and their riders performed a SJT with obstacles set at 80 cm height using a heart rate monitor (M430 with H10 sensor). Physical examination and blood samples, for...
Baldwin CM, Gillen A.To evaluate three different jejunal transection angles for end-to-end jejunojejunostomies, comparing construction time, lumen size, and suture number. Methods: Ex vivo cadaver study. Methods: Eight euthanized horses each had three mid-jejunal specimens harvested. Methods: Jejunal segments were assigned to one of three groups (A30, A45, and A60) and transected at 30, 45, or 60°, respectively. Following transection, a standardized handsewn single-layer interrupted modified Lembert anastomosis was performed, and construction time and number of sutures placed were recorded. Anastomotic index (AI)...
Ablondi M, Eriksson S, Mikko S.Fragile foal syndrome (FFS) is a disease caused by a recessive lethal missense mutation in the PLOD1 gene located on ECA2. Despite its harmful effect, a relatively high frequency of FFS carriers was observed in Warmblood breeds spanning from 7.4% in a random sample of Swedish Warmblood breed to 17% in the Hanoverian and Danish Warmblood, indicating potential heterozygous advantage. Balancing selection can be further studied based on haplotype blocks and via detection of heterozygosity-rich region (ROHet) around the target of selection. In this study we evaluated the presence of haplotype block...
Liedtke AM, Meijer H, Horstmann S, von Reitzenstein C, Rump I, Kirsch K.Eventing is an Olympic equestrian discipline comprising dressage, cross-country, and show jumping, with the cross-country phase imposing the greatest physical demands on horses. This study presents a composite model to estimate energy expenditure during the cross-country phase, integrating physiological data (heart rate-derived VO2 and lactate-based anaerobic estimates) with external workload indicators (GPS-derived speed, elevation, and course complexity). Model development was based on 691 rides from 256 horses across 232 events at 2-star to 5-star competition levels. The analysis showed tha...
Faithfull R, Lewis K, Drury E, McBride S.Despite welfare concerns, conflict behaviours (indicative of momentary states of acute stress) are common in horses during dressage competitions. Identifying factors that affect conflict behaviours during competition therefore has the potential to improve equine welfare. The aim of this exploratory study was to assess the effect of bridle type (double versus snaffle) in relation to other potential affecting factors (e.g., average head angle, competition level and type, tack variation) on conflict behaviours during dressage competition. An ethogram was created to analyse the conflict behaviour ...
Zupan Šemrov M, Přibylová L, Gobbo E.Equine locomotion emerges from a dynamic interplay between morphology, biomechanics, and functional demands. This study examines the relationship between morphological measurements and gait kinematics in Lipizzan horses, a breed renowned for its diverse work tasks and standardized environmental conditions. These horses offer a unique opportunity to explore task-specific adaptations in biomechanics, with significant implications for breeding strategies and welfare practices. Unassigned: The study involved 71 healthy Lipizzan horses that were housed at the Lipica stud farm and performed various ...
Herkenhoff ME.MicroRNAs (miRNAs) are molecules that regulate gene expression by targeting the 3' untranslated region (UTR) of mRNAs. They are essential in numerous biological processes like growth, metabolism, and muscle development. miRNA research has become crucial in livestock breeding, offering solutions for improving animal health and productivity. This review focuses on miRNAs' roles in equine performance, reproduction, and disease, highlighting key findings and future applications in these areas. It discusses the use of circulating miRNAs (ci-miRNA) as biomarkers for athletic performance, particularl...
Berni P, Del Bue M, Conti V, Andreoli V, Ramoni R, Angelone M, Squassino GP, Bari E, Torre ML, Rinaldi M, Dotti S, Rossi R, Yusuf I, Mauri P....Most in vivo studies on MSC-secretome for osteoarthritis (OA) have relied on animal models, using products lacking pharmaceutical quality, not formulated for clinical use, and insufficiently characterized, limiting knowledge of its effectiveness. This study reports veterinary clinical trials on dogs and horses with spontaneous OA: in dogs (26 subjects), the trial is randomized, double-blinded, and controlled; in horses, 5 clinical cases were treated for safety assessment. Treatment consisted of hyaluronic acid with either lyosecretome - a freeze-dried, injectable MSC-secretome obtained through...
Gozalo-Marcilla M, Redondo JI, Bettschart-Wolfensberger R, Domenech L, Doménech J, Johnston GM, Taylor PM.To report on the Confidential Enquiry into Perioperative Equine Fatalities 4 (CEPEF4). Methods: Confidential, observational, prospective, multicentre, cohort study. Methods: 47,396 horses/ponies undergoing general anaesthesia (GA). Methods: Characteristics of each GA (249 variables) were collected. Outcomes after seven days were ALIVE (or discharged), EUTHANASIA or DEAD. Logistic regression analysed patient demographics and the anaesthetic drugs (p < 0.05). Results: Data were collected from 47,396 GAs in 93 centres in 28 countries. Death rates were 1.2% overall, 0.6% for cases classified as NO...
Kroschel L, Pilger F, Aurich J, Nagel C, Aurich C.Horses in training are often stabled individually, but this is increasingly questioned. We have investigated the effects of different stabling systems in Warmblood stallions during a 12-week pretraining programme. Stallions were 24 months old and housed either in a group stable (Group 24, n = 9) or in individual boxes (Box 24, n = 10), or they were 30 months of age and housed in individual boxes (Box 30, n = 10). Cortisol, heart rate, heart rate variability (HRV), body development, injuries and selected behaviour patterns were analysed (1) at transfer from pasture to stable and (2) the...
Kwaß LM, Khiaosa-Ard R, Zebeli Q, Sulyok M, Milojevic V, Metzler-Zebeli BU.The occurrence of biotoxins and chemical residues in marketed horse feeds has direct influences on horse health but has not been studied yet. Objective: The study investigated the exposure and health implications of contaminants in various horse feedstuffs available on the European market. Methods: A total of 108 feed samples representing diverse product categories such as hay, processed roughage products, grains, and various supplementary feeds were collected from different European countries and analyzed for contaminants, including mycotoxins, phytoestrogens, pesticides, and veterinary drug ...
Slavik K, Whitlock R, Johnson A.Botulism is a severe and often fatal disease in equine patients worldwide. Clostridium botulinum is a ubiquitous soil organism which produces a potent neurotoxin resulting in neuromuscular blockade and flaccid paralysis in affected animals. Definitive diagnosis is often impractical or impossible, leading to diagnosis and treatment based on clinical experience and presenting signs. Delay in case identification and treatment results in rapid deterioration of the patient. Treatment of recumbent equine botulism cases presents challenges due to patient size and requires intensive nursing care. This...
Connard SS, Schnabel LV.This review explores the use of biologics in the treatment of tendon and ligament injuries in horses, focusing on current and emerging therapies aimed at enhancing tissue repair and regeneration. It discusses the role of scaffold-based therapies, growth factors, blood-derived and tissue-derived biologics, and gene therapy as biologic regenerative therapies for improving healing outcomes. The review evaluates the mechanisms, efficacy, and challenges of biologics in clinical applications, highlighting recent advances and clinical studies. It provides an overview of current trends and future dire...
Legere RM, Ott JA, Poveda C, Vanover D, Borba KER, Yeon Joo J, Martin CL, da Silveira BP, Bray JM, Landrock K, Wright GA, Blazier JC, Hillhouse AE....Inhalation of Rhodococcus equi causes severe pneumonia in humans and animals worldwide, most commonly affecting horse foals. The standard for preventing R. equi pneumonia in foals is transfusion of hyperimmune plasma, which is expensive and carries the risk of adverse effects. Our goal was to passively immunize foals against R. equi by nebulizing mRNA encoding an equine monoclonal antibody (mAb) against the virulence-associated protein A (VapA) directly into the lungs. VapA-specific memory B cells from an immunized horse were used to identify and select the sequence for an equine immunoglobuli...
Pluim M, Reynolds A, McClure S.High-power laser therapy and extracorporeal shock wave therapy (ESWT) can be safely used to treat tendon and ligament injuries in horses, and the potential beneficial effects have been described. The power of low level lasers is not sufficient for treatment of tendon and ligament injuries in horses. ESWT is used more often to treat tendon and ligament injuries than it is for any other type of condition in horses, but there is limited supporting scientific evidence. Further research should focus on establishing dosage and treatment protocols for both laser therapy and ESWT in horses with clinic...
Ellis KL, Giancola S.Rehabilitation for tendon/ligament injury requires a multimodal approach to reduce pain, restore range of motion, improve proprioception/neuromotor control, and improve strength/endurance. Multiple tools are available to accomplish these goals. The rehabilitation program must be tailored to the individual patient regardless of injury type in order to return the horse to full athletic activity and reduce the risk of reinjury.
Tay A, McMaster M.Equine tendon lacerations are not uncommon secondary to traumatic wounds and degloving lacerations. These wounds are often contaminated and, therefore, basic principles of wound assessment and management are critical to identify the extent of an injury. Ancillary tools to aid physical examination include radiography, ultrasonography, and synoviocentesis (eg, if involving a joint and/or tendon sheath). Prolonged convalescence period, continued external coaptation, and controlled exercise are mainstays of treatment following tenorrhaphy. A poor prognosis for return to full athletic function is e...
Horne CR, Redding WR.The location of a suspensory ligament (SL) injury heavily influences the clinical presentation, prognosis, and treatment options. Diagnostic imaging is necessary to provide an accurate diagnosis and is critical to ensure the institution of the most appropriate treatment. The hindlimb proximal SL in particular can be challenging to diagnosis, carries a guarded prognosis, and typically requires aggressive treatment to achieve soundness.
Hellige M, Geburek F.Diagnostic imaging is an important part of the diagnostic approach in equine spinal ataxia especially with the cervical spine being commonly involved. The spinal cord may be affected by a variety of conditions including cervical vertebral malformations, osteoarthritis of the articular process joints or less commonly neoplasia. Advanced imaging techniques such as myelography are more accurate in diagnosing spinal cord compression and may be performed under general anesthesia in neutral, flexed and extended positions of the cervical spine. The use of ultrasound is non-invasive and allows ultraso...
de Preux M, Precht C, Becker R, Stieglitz L, Easley J, Koch C.Trigeminal-mediated headshaking is a neuropathic disorder in horses, characterized by signs of regional pain similar to trigeminal neuralgia in humans. The injection of glycerol into the trigeminal cistern to ablate pain-conducting nerve fibers within the trigeminal ganglion -known as glycerol rhizotomy- is a well-established treatment in human medicine. This study compares two approaches to the equine trigeminal cistern using a navigation system for guiding needle placement, a previously described ventral and a newly developed transmandibular lateral approach. The surgical accuracy and risk o...
Crabtree NE, Capper AM, McKinnon LH, Epstein KL.The objective was to compare perioperative factors that may influence clinician decisions regarding antimicrobial therapy duration and outcomes in horses undergoing exploratory celiotomy. Unassigned: Horses > 1 mo of age undergoing exploratory celiotomy for colic that survived without repeat celiotomy for ≥ 5 d. Unassigned: Retrospective cohort study. Cases were grouped by duration of antimicrobial therapy: G1, ≤ 24 h; G2, 1 to 3 d; G3, > 3 d. Admission, surgical, and postoperative data from the medical records and long-term outcome assessed telephone follow-up were compared among g...
Maguire M, Brusie R.To determine the outcome of skeletally mature performance horses with subchondral bone cysts and fissures in the proximal aspect of the first phalanx treated by lag screw compression. Unassigned: Case records of horses that underwent lag screw compression to treat subchondral bone lesions in the proximal aspect of the first phalanx were reviewed. Performance horses > 5 years old with lameness referrable to the fetlock region; radiographic or other advanced imaging evidence of subchondral bone lesions, with no other concurrent cause for lameness; and at least 6 months of follow-up data were inc...
Tarillion M, Hertzsch R, Richter A.Since 28.01.2022, veterinary medicinal products must be used in accordance with the conditions of authorization (Regulation (EU) 2019/6, Article 106). This entails further restrictions on therapeutic freedom, e. g., with regard to dose deviations. To date, there is no data available in equine medicine on the scope of off-label use as any use deviating from the expert information for antibiotics, on the basis of which the feasibility of implementing the new regulations in Germany can be assessed.To collect data on the off-label use of antibiotics, a Germany-wide anonymous online survey was th...
Ellis K, Van Zeeland EM, Ashton L, Wist S, Broeckling C, Harris M, Frisbie DD, Sikes KJ.To (1) identify tissue-specific metabolic profiles of the superficial digital flexor tendon (SDFT), deep digital flexor tendon (DDFT), and suspensory ligament (SL) and (2) evaluate metabolic profile differences in the SDFT, DDFT, and SL between the equine forelimb and hindlimb. Unassigned: 2 SDFT, DDFT, and SL specimens were collected from the forelimbs and hindlimbs of 10 horses of mixed breed, age, and sex that were euthanized for other reasons. One specimen was processed for histology to confirm that there were no underlying soft-tissue pathologies. One specimen was processed for 2 forms of...
Munoz Moran JA.This study was performed to evaluate the efficacy of intra-articular (IA) injections of a combination of platelet rich plasma (PRP) and hyaluronic acid (HA) on joint effusion following arthroscopic removal of OCD in the tarso-crural joint (TCJ) in young Andalusian horses. Methods: Forty Andalusian horses diagnosed with OCD of the distal intermediate ridge of the tibia (DIRT) were included in the study. Horses enrolled in this study had persisting synovial effusion after arthroscopic removal of OCD in the TCJ. A subjective semi-quantitative effusion score was adopted in the study to define the ...
Peeters MWJ, Ott S, van Veggel E, Berner D, Perrier M.Limited reports in the literature are available regarding desmitis of the palmar/plantar ligaments of the proximal interphalangeal joint (PL-PIPJ); the clinical significance of such injuries is unknown. Objective: To describe the ability to differentiate the PL-PIPJ on low-field magnetic resonance (MR) examination. To describe the injury characteristics of the PL-PIPJ on MR examination and the correlation with clinical features and lameness. Methods: Retrospective case series. Methods: Data and MR images of 29 horses were collected from the databases of three institutions. Horses were included...
Thouless ME, Bryden AS, Flewett TH, Woode GN, Bridger JC, Snodgrass DR, Herring JA.Human, piglet, mouse, foal, lamb, calf and rabbit rotaviruses all infected, but could not readily be subcultured in LLC MK2 cells. Cells infected with mouse and calf rotaviruses reacted by indirect immunofluorescence (FA) with convalescent serum from children, piglets, mice, foals, lambs, calves or rabbits, taken after rotavirus infection. Human, calf, piglet, mouse and foal rotaviruses reacted with human, calf, mouse, foal and lamb convalescent serum by complement fixation (CF). It was not possible to distinguish between different rotaviruses by CF or FA. Neutralization tests, however, detect...
Morales MA, Barrandeguy M, Fabbri C, Garcia JB, Vissani A, Trono K, Gutierrez G, Pigretti S, Menchaca H, Garrido N, Taylor N, Fernandez F, Levis S....West Nile virus (WNV) was isolated from the brains of 3 horses that died from encephalitis in February 2006. The horses were from different farms in central Argentina and had not traveled outside the country. This is the first isolation of WNV in South America.
Asplin KE, Sillence MN, Pollitt CC, McGowan CM.The purpose of this study was to determine the effects of prolonged administration of insulin, whilst maintaining normal glucose concentrations, on hoof lamellar integrity in vivo on healthy ponies with no known history of laminitis or insulin resistance. Nine clinically healthy, unrelated ponies were randomly allocated to either a treatment group (n =5; 5.9+/-1.7 years) or control group (n =4; 7.0+/-2.8 years). The treatment group received insulin via a euglycaemic hyperinsulinaemic clamp technique modified and prolonged for up to 72 h. Control ponies were infused with an equivalent volume of...
Leroy G, Mary-Huard T, Verrier E, Danvy S, Charvolin E, Danchin-Burge C.Effective population sizes of 140 populations (including 60 dog breeds, 40 sheep breeds, 20 cattle breeds and 20 horse breeds) were computed using pedigree information and six different computation methods. Simple demographical information (number of breeding males and females), variance of progeny size, or evolution of identity by descent probabilities based on coancestry or inbreeding were used as well as identity by descent rate between two successive generations or individual identity by descent rate. Results: Depending on breed and method, effective population sizes ranged from 15 to 133 ...
Vidal MA, Walker NJ, Napoli E, Borjesson DL.Mesenchymal stem cells (MSCs) from adult and neonatal tissues are intensively investigated for their use in regenerative medicine. The purpose of this study was to compare the onset of replicative senescence in MSCs isolated from equine bone marrow (BMSC), adipose tissue (ASC), and umbilical cord tissue (UCMSC). MSC proliferation (cell doubling), senescence-associated β-galactosidase staining, telomere length, Sox-2, and lineage-specific marker expression were assessed for MSCs harvested from tissues of 4 different donors. The results show that before senescence ensued, all cell types prolife...
Schmiedel J, Falgenhauer L, Domann E, Bauerfeind R, Prenger-Berninghoff E, Imirzalioglu C, Chakraborty T.Multiresistant Gram-negative bacteria producing extended-spectrum β-lactamases (ESBLs) are an emerging problem in human and veterinary medicine. This study focused on comparative molecular characterization of β-lactamase and ESBL-producing Enterobacteriaceae isolates from central Hesse in Germany. Isolates originated from humans, companion animals (dogs and cats) and horses. Results: In this study 153 (83.6%) of the human isolates (n = 183) and 163 (91.6%) of the animal isolates (n = 178) were confirmed as ESBL producers by PCR and subsequent sequencing of the PCR amplicons. Predomin...
Pelkonen S, Lindahl SB, Suomala P, Karhukorpi J, Vuorinen S, Koivula I, Väisänen T, Pentikäinen J, Autio T, Tuuminen T.Streptococcus equi subspecies zooepidemicus (S. zooepidemicus) is a zoonotic pathogen for persons in contact with horses. In horses, S. zooepidemicus is an opportunistic pathogen, but human infections associated with S. zooepidemicus are often severe. Within 6 months in 2011, 3 unrelated cases of severe, disseminated S. zooepidemicus infection occurred in men working with horses in eastern Finland. To clarify the pathogen's epidemiology, we describe the clinical features of the infection in 3 patients and compare the S. zooepidemicus isolates from the human cases with S. zooepidemicus isolates...
Baptiste KE, Williams K, Willams NJ, Wattret A, Clegg PD, Dawson S, Corkill JE, O'Neill T, Hart CA.We determined the molecular characteristics of methicillin-resistant staphylococci from animals and staff at a small animal and equine hospital. Methicillin-resistant Staphylococcus aureus (MRSA) identical to human EMRSA-15 was found in dogs and hospital staff. In contrast, 5 distinct MRSA strains were isolated from horses but not from hospital staff.
Onyiche TE, Suganuma K, Igarashi I, Yokoyama N, Xuan X, Thekisoe O.Equine Piroplasmosis (EP) is a tick-borne disease caused by apicomplexan protozoan parasites, and . The disease is responsible for serious economic losses to the equine industry. It principally affects donkeys, horses, mules, and zebra but DNA of the parasites has also been detected in dogs and camels raising doubt about their host specificity. The disease is endemic in tropical and temperate regions of the world where the competent tick vectors are prevalent. Infected equids remain carrier for life with infection, whilst, infection with is cleared within a few years. This review focuses on...
Goodrich LR, Nixon AJ.The medical treatment of osteoarthritis (OA) in the horse is one of the most utilized therapeutic regimens in the equine practice. It is important to understand the anatomy of synovial joints and the pathophysiology of the disease process to treat OA adequately. Once a thorough understanding of the disease process is comprehended the proper combination of systemic nonsteroidal anti-inflammatory drugs (NSAIDs), intraarticular steroids, viscosupplementation and chondroprotectants can be used to treat the disease and inhibit further progression of degenerative changes to the cartilage surface. Th...
Journal of medical entomologyOctober 5, 2006
Volume 43, Issue 5 936-946 doi: 10.1603/0022-2585(2006)43[936:hbahba]2.0.co;2
Balenghien T, Fouque F, Sabatier P, Bicout DJ.After 35 yr of disease absence, West Nile virus (family Flaviviridae, genus Flavivirus, WNV) circulation has been regularly detected in the Camargue region (southern France) since 2000. WNV was isolated from Culex modestus Ficalbi, which was considered the main vector in southern France after horse outbreaks in the 1960s. Recent WNV transmissions outside of the Cx. modestus distribution suggested the existence of other vectors. To study potential WNV vectors, horse- and bird-baited traps and human landing collections of mosquitoes were carried out weekly from May to October 2004 at two Camargu...
Reef VB, Bonagura J, Buhl R, McGurrin MK, Schwarzwald CC, van Loon G, Young LE.Murmurs and arrhythmias are commonly detected in equine athletes. Assessing the relevance of these cardiovascular abnormalities in the performance horse can be challenging. Determining the impact of a cardiovascular disorder on performance, life expectancy, horse and rider or driver safety relative to the owner's future expectations is paramount. A comprehensive assessment of the cardiovascular abnormality detected is essential to determine its severity and achieve these aims. This consensus statement presents a general approach to the assessment of cardiovascular abnormalities, followed by a ...
Peregrine AS, Molento MB, Kaplan RM, Nielsen MK.Parascaris equorum and cyathostomins are currently considered the most important parasites of horses and have traditionally been controlled with anthelmintics belonging to three drug classes: benzimidazoles, the tetrahydropyrimidine pyrantel, and macrocyclic lactones. Unfortunately, resistance to benzimidazoles, and to a lesser extent pyrantel, is widespread in cyathostomins around the world. Furthermore, resistance to macrocyclic lactones appears to be in the early stages of development in cyathostomins in multiple locations. In contrast, P. equorum populations have remained susceptible to th...
Wise LN, Kappmeyer LS, Mealey RH, Knowles DP.Equine piroplasmosis is caused by one of 2 erythrocytic parasites Babesia caballi or Theileria equi. Although the genus of the latter remains controversial, the most recent designation, Theileria, is utilized in this review. Shared pathogenesis includes tick-borne transmission and erythrolysis leading to anemia as the primary clinical outcome. Although both parasites are able to persist indefinitely in their equid hosts, thus far, only B. caballi transmits across tick generations. Pathogenesis further diverges after transmission to equids in that B. caballi immediately infects erythrocytes, wh...
Walsh C, Gangloff M, Monie T, Smyth T, Wei B, McKinley TJ, Maskell D, Gay N, Bryant C.LPS signals through a membrane bound-complex of the lipid binding protein MD-2 and the receptor TLR4. In this study we identify discrete regions in both MD-2 and TLR4 that are required for signaling by lipid IVa, an LPS derivative that is an agonist in horse but an antagonist in humans. We show that changes in the electrostatic surface potential of both MD-2 and TLR4 are required in order that lipid IVa can induce signaling. In MD-2, replacing horse residues 57-66 and 82-89 with the equivalent human residues confers a level of constitutive activity on horse MD-2, suggesting that conformational...
Baumber J, Ball BA, Gravance CG, Medina V, Davies-Morel MC.The objective of this study was to examine the influence of reactive oxygen species (ROS), generated through the use of the xanthine (X)-xanthine oxidase (XO) system, on equine sperm motility, viability, acrosomal integrity, mitochondrial membrane potential, and membrane lipid peroxidation. Equine spermatozoa were separated from seminal plasma on a discontinuous Percoll gradient, and spermatozoa were incubated with 0.6 mM X and 0.05 U/mL XO for 30 minutes. Catalase (150 U/mL), superoxide dismutase (SOD, 150 U/mL), or glutathione (GSH, 1.5 mM) were evaluated for their ability to preserve sperm ...
Hammond SA, Cook SJ, Lichtenstein DL, Issel CJ, Montelaro RC.Equine infectious anemia virus (EIAV) provides a natural model system by which immunological control of lentivirus infections may be studied. To date, no detailed study addressing in parallel both the humoral and cellular immune responses induced in horses upon infection by EIAV has been conducted. Therefore, we initiated the first comprehensive characterization of the cellular and humoral immune responses during clinical progression from chronic disease to inapparent stages of EIAV infection. Using new analyses of antibody avidity and antibody epitope conformation dependence that had not been...
Ericsson AC, Johnson PJ, Lopes MA, Perry SC, Lanter HR.Horses are exquisitely sensitive to non-specific gastrointestinal disturbances as well as systemic and extraintestinal conditions related to gut health, yet minimal data are available regarding the composition of the microbiota present in the equine stomach, small intestine, and cecum and their relation to fecal microbiota. Moreover, there is minimal information regarding the concordance of the luminal and mucosal microbial communities throughout the equine gut. Illumina-based 16S rRNA gene amplicon sequencing of the luminal and mucosal microbiota present in seven regions of the gastrointestin...
Catlin BW.The clinical significance, Gram stain reaction, and genus affiliation of Gardnerella vaginalis have been controversial since Gardner and Dukes described the organism as the cause of "nonspecific vaginitis," a common disease of women which is now called bacterial vaginosis. The organism was named G. vaginalis when taxonomic studies showed that it was unrelated to bacteria in various genera including Haemophilus and Corynebacterium. Electron microscopy and chemical analyses have elucidated the organism's gram-variable reaction. Controversy over the etiology of bacterial vaginosis was largely res...
Vidal MA, Kilroy GE, Lopez MJ, Johnson JR, Moore RM, Gimble JM.To characterize equine adipose tissue-derived stromal cell (ASC) frequency and growth characteristics and assess of their adipogenic and osteogenic differentiation potential. Methods: In vitro experimental study. Methods: Horses (n=5; aged, 9 months to 5 years). Methods: Cell doubling characteristics of ASCs harvested from supragluteal subcutaneous adipose tissue were evaluated over 10 passages. Primary, second (P2), and fourth (P4) passage ASCs were induced under appropriate conditions to undergo adipogenesis and osteogenesis. Limit dilution assays were performed on each passage to determine ...
Rubin CT, Lanyon LE.Rosette strain gauges were attached to the midshaft of the radius and tibia of two horses and two dogs, which ran on a treadmill through their entire range of speed and gait. The relative magnitudes of the principal strains on the opposite cortices of each bone remained constant through the stance phase of the stride, and their orientation varied by a maximum of only 14 degrees through the entire speed range. The maximum strain rate increased linearly with speed, but the peak strain magnitude was also dependent upon the gait used, increasing incrementally by up to 59% at the transition from wa...
White LM, Sussman MS, Hurtig M, Probyn L, Tomlinson G, Kandel R.To prospectively assess T2 mapping characteristics of normal articular cartilage and of cartilage at sites of arthroscopic repair, including comparison with histologic results and collagen organization assessed at polarized light microscopy (PLM). Methods: Study protocol was compliant with the Canadian Council on Animal Care Guidelines and approved by the institutional animal care committee. Arthroscopic osteochondral autograft transplantation (OAT) and microfracture arthroplasty (MFx) were performed in knees of 10 equine subjects (seven female, three male; age range, 3-5 years). A site of art...
Guo Y, Wang M, Kawaoka Y, Gorman O, Ito T, Saito T, Webster RG.In March 1989 a severe outbreak of respiratory disease occurred in horses in the Jilin and Heilongjiang provinces of Northeast China that caused up to 20% mortality in some herds. An influenza virus of the H3N8 subtype was isolated from the infected animals and was antigenically and molecularly distinguishable from the equine 2 (H3N8) viruses currently circulating in the world. The reference strain A/Equine/Jilin/1/89 (H3N8) was most closely related to avian H3N8 influenza viruses. Sequence comparisons of the entire hemagglutinin (HA), nucleoprotein (NP), neuraminidase (NA), matrix (M), and NS...
Timoney JF.Streptococci pathogenic for the horse include S. equi (S. equi subsp. equi), S. zooepidemicus (S. equi subsp. zooepidemicus), S. dysgalactiae subsp. equisimilis and S. pneumoniae capsule Type III. S. equi is a clonal descendent or biovar of an ancestral S. zooepidemicus strain with which it shares greater than 98% DNA homology and therefore expresses many of the same proteins and virulence factors. Rapid progress has been made in identification of virulence factors and proteins uniquely expressed by S. equi. Most of these are expressed either on the bacterial surface or are secreted. Notable e...
Hill EW, Gu J, Eivers SS, Fonseca RG, McGivney BA, Govindarajan P, Orr N, Katz LM, MacHugh DE.Variants of the MSTN gene encoding myostatin are associated with muscle hypertrophy phenotypes in a range of mammalian species, most notably cattle, dogs, mice, and humans. Using a sample of registered Thoroughbred horses (n = 148), we have identified a novel MSTN sequence polymorphism that is strongly associated (g.66493737C>T, P = 4.85x10(-8)) with best race distance among elite racehorses (n = 79). This observation was independently validated (P = 1.91x10(-6)) in a resampled group of Thoroughbreds (n = 62) and in a cohort of Thoroughbreds (n = 37, P = 0.0047) produced by the same trainer...
Telford EA, Watson MS, Aird HC, Perry J, Davison AJ.The complete DNA sequence of equine herpesvirus 2 (EHV-2) strain 86/67 was determined. The genome is 184,427 bp in size and has a base composition of 57.5% G + C. Unusually for a herpesvirus, about a third of the sequence distributed in several large blocks appears not to encode proteins. The 79 open reading frames that were identified as probably polypeptide-coding are predicted to encode 77 distinct proteins. Amino acid sequence comparisons confirmed that EHV-2 is a gamma-herpesvirus that is genetically collinear with herpesvirus saimiri (HVS; a gamma 2-herpesvirus) and Epstein-Barr virus (E...
Cappelli K, Felicetti M, Capomaccio S, Spinsanti G, Silvestrelli M, Supplizi AV.Adequate stress response is a critical factor during athlete horses' training and is central to our capacity to obtain better performances while safeguarding animal welfare. In order to investigate the molecular mechanisms underlying this process, several studies have been conducted that take advantage of microarray and quantitative real-time PCR (qRT-PCR) technologies to analyse the expression of candidate genes involved in the cellular stress response. Appropriate application of qRT-PCR, however, requires the use of reference genes whose level of expression is not affected by the test, by ge...
