Standardbred horses are a breed known for their performance in harness racing, characterized by their ability to trot or pace at high speeds. This breed is distinguished by its well-muscled build, strong legs, and calm temperament. Standardbreds are primarily used in racing but are also versatile in other equestrian activities, including riding and driving. Their genetic lineage can be traced back to the late 18th century, with the establishment of the breed registry in the United States. This page compiles peer-reviewed research studies and scholarly articles that explore the genetics, physiology, and performance characteristics of Standardbred horses, as well as their management and health considerations in various equine disciplines.
Delvescovo B, Mullen KR, Eicker SW, Ivanek R, Ainsworth DM.Previously we described a clustering of dysphagic foal cases on a Pennsylvania (PA) Standardbred farm which was associated with exposure of pregnant mares to high concentrations of polycyclic aromatic hydrocarbons (PAHs) in the well water. The effect of dysphagia on future athleticism was uncertain. Objective: To determine if, as adults, dysphagic foals were less likely to race and if athleticism (age of first race, Speed Index and Earnings Per Start Index) differed from that of healthy foals that raced as adults. Methods: Prospective cohort study. Methods: All foals born during the study peri...
Rossi TM, Milwid RM, Moore A, O'Sullivan TL, Greer AL.Infectious respiratory disease is a common cause of morbidity among racehorses. Quantification of contact patterns in training facilities could help inform disease prevention strategies. The study objectives were to: i) describe the contact network among horses, locations, and humans at a Standardbred horse training facility in Ontario; ii) describe the characteristics of highly influential individuals; and iii) investigate how management changes alter the network metrics and discuss the potential implications for disease transmission. Proximity loggers detected contacts among horses, staff, a...
Stucchi L, Alberti E, Stancari G, Conturba B, Zucca E, Ferrucci F.Mild-moderate equine asthma (MEA) is a common disease of young racehorses characterized by inflammation of the lower airways diagnosed by cytological examination of bronchoalveolar lavage fluid (BALF), and it is considered an important cause of poor performance. The most common parameter of athletic capacity associated with horse performance is the speed at 4 mmol/L of lactate (VLA4). The aim of the present work was to evaluate the relation between the different BALF inflammatory cells and VLA4 in racehorses affected by MEA. A population of Standardbred racehorses that underwent an accurate pr...
Bauquier J, Tudor E, Bailey S.Doramapimod, a p38 MAPK inhibitor, is a potent anti-inflammatory drug that decreases inflammatory cytokine production in equine whole blood in vitro. It may have benefits for treating systemic inflammation in horses. Objective: To determine whether doramapimod is well tolerated when administered IV to horses, and whether it has anti-inflammatory effects in horses in a low-dose endotoxemia model. Methods: Six Standardbred horses. Methods: Tolerability study, followed by a blinded, randomized, placebo-controlled cross-over study. Horses were given doramapimod, and clinical and clinicopathologica...
Bazzano M, Laghi L, Zhu C, Lotito E, Sgariglia S, Tesei B, Laus F.In the present study, data related to the metabolomics of saliva and serum in trained standardbred horses are provided for the first time. Metabolomic analysis allows to analyze all the metabolites within selected biofluids, providing a better understanding of biochemistry modifications related to exercise. On the basis of the current advances observed in metabolomic research on human athletes, we aimed to investigate the metabolites' profile of serum and saliva samples collected from healthy standardbred horses and the relationship with physical exercise. Twelve trained standardbred horses we...
There are several bioengineering solutions aimed at improving human health and welfare. Smart electrodes based on textile substrates have met the growing demand for comfort, reliability, and robustness when acquiring physiological signals. Objective: Given the importance of good quality electrocardiograms (ECG) in equine sports medicine, this study focuses on the validation of smart textile electrodes to acquire ECG signals in horses during treadmill exercise. Methods: The performance of the smart textile electrodes is compared with standard silver/silver chloride (Ag/AgCl) electrodes in terms...
Nostell K, Lindåse S, Winqvist E, Bröjer J.Obesity is associated with insulin resistance, vascular dysfunction and altered cortisol metabolism both in humans and in horses. Objective: Evaluate the effect of weight gain induced by a haylage diet low in nonstructural carbohydrates (NSC) on insulin sensitivity, blood pressure and serum cortisol concentrations. Methods: In vivo experiment. Methods: Nine adult Standardbred mares fed a fat supplemented haylage diet at 250% of the horses' daily metabolisable energy requirements for 22 weeks. Horses were then turned out on pasture for 4 weeks. Insulin sensitivity (SI ) was measured before an...
Kallerud AS, Fjordbakk CT, Hendrickson EHS, Persson-Sjodin E, Hammarberg M, Rhodin M, Hernlund E.Lameness evaluation of Standardbred trotters can be challenging due to discrepancies in observed movement asymmetry between in-hand and track exercise, and between different trotting speeds. There are few studies on objective measurement of movement in Standardbreds, and little knowledge regarding biological variation and clinical significance of measured movement asymmetry in this breed. Objective: To quantify the prevalence and magnitude of objectively measured movement asymmetry in young Standardbred trotters, and identify associations with trainer, sex, height, track type and in-hand measu...
Bertuglia A, Pagliara E, Manca F, Pozzolo P, Mannelli A.The objective of this study was to report recovery time, retirement rate, racing performance, and presence of compensation pattern after musculoskeletal injuries (MSIs) in Standardbred racehorses (STBRs). This is a retrospective single open-cohort study, enrolling 356 STBRs in training in a single racetrack. Musculoskeletal injury was defined as any training-related injury after which the horse did not train for at least 15 days. The first and second MSIs encountered during the horse's racing career were considered. Medical records, training logbooks, and racing data were reviewed to determin...
Buhl R, Hesselkilde EM, Carstensen H, Fenner MF, Jespersen T, Tfelt-Hansen J, Michael Sattler S.Cardiac arrhythmias in horses are diagnosed by auscultation or electrocardiogram (ECG), which results in a low sensitivity for detecting arrhythmias that occur sporadically. Implantable loop recorders (ILRs) are small ECG devices placed subcutaneously, to automatically detect arrhythmias in human patients. Objective: To test ILRs ability to detect atrial fibrillation (AF) in horses. Furthermore, we hypothesised that anatomical location of the implant site might influence signal quality. Signal quality was evaluated both during exercise and over time. Methods: Experimental study. Methods: In fi...
Pasolini MP, Pezzella R, Santoro P, Cocchia N, Greco M, Del Prete C, Della Valle G, Auletta L.Equine exertional rhabdomyolysis (ER) is a well-recognized clinical syndrome affecting racehorses. Prevalence analysis of ER showed that female sex was a significant risk factor. The aim of this research was to evaluate the differences and correlations in the serum activity of muscle enzymes and the stage of the estrous cycle in ER-susceptible and control (C) mares. Serum muscle enzyme activity before and after exercise and sex hormones were analyzed in the two groups of mares. Ten cyclic ER and 10 cyclic C mares were examined weekly for 4 weeks. During diestrus, ER horses had significantly hi...
Stokes SM, Burns TA, Watts MR, Bertin FR, Stefanovski D, Medina-Torres CE, Belknap JK, van Eps AW.Continuous digital hypothermia (CDH) prevents lamellar failure in the euglycemic hyperinsulinemic clamp (EHC) model of laminitis, but the protective mechanisms are unclear. Objective: To determine if CDH inhibits lamellar inflammatory signaling in the EHC model of laminitis. Methods: Eight Standardbred horses. Methods: Prospective experimental study. Horses underwent an EHC, with 1 forelimb treated with CDH and the other kept at ambient temperature (AMB). Horses were euthanized 48 hours after initiation of the EHC and lamellar tissue was analyzed via polymerase chain reaction (pro-inflammato...
Fretheim-Kelly Z, Fjordbakk CT, Fintl C, Krontveit R, Strand E.Bits have often been incriminated as a cause of upper respiratory tract obstruction in horses; however, no scientific studies are available to confirm or refute these allegations. Clinical signs of dynamic laryngeal collapse associated with poll flexion (DLC) are induced when susceptible horses are ridden or driven into the bit. Objective: To determine whether use of Dr Cook's™ Bitless Bridle, instead of a conventional snaffle bit bridle, would reduce the severity of DLC in affected horses measured objectively using inspiratory tracheal pressures. Methods: Intervention study using each horse...
Campolo A, Frantz MW, de Laat MA, Hartson SD, Furr MO, Lacombe VA.Endocrinopathic laminitis is pathologically similar to the multi-organ dysfunction and peripheral neuropathy found in human patients with metabolic syndrome. Similarly, endocrinopathic laminitis has been shown to partially result from vascular dysfunction. However, despite extensive research, the pathogenesis of this disease is not well elucidated and laminitis remains without an effective treatment. Here, we sought to identify novel proteins and pathways underlying the development of equine endocrinopathic laminitis. Healthy Standardbred horses ( = 4/group) were either given an electrolyte in...
Solé M, Lindgren G, Bongcam-Rudloff E, Jansson A.There is a lack of research on the benefits and risks of shoeing conditions in harness racing. Thus, our objectives were to: (a) investigate whether velocity times (VT; s/km) are affected by racing unshod (N = 76,932 records on 5,247 horses); (b) determine the potential risks of galloping, being penalized, and disqualification when competing unshod (N = 111,755 records on 6,423 horses); and (c) identify additional environmental factors that affect VT and risks. VT was found to be significantly influenced by shoeing condition (e.g., unshod, shod front, shod hind, or fully shod), but also by...
Fintl C, Krontveit R, Risberg Å, Hanche-Olsen S, Slack J.The Norwegian-Swedish Coldblooded Trotter (NSCT) is an important breed in Norwegian and Swedish harness racing. In spite of this, little is known about its cardiac measurements and factors that may influence these. The aims of this study were to establish reference intervals (RI) for a series of conventional echocardiographic variables, primarily of the left heart, in NSCTs in race training and to evaluate any effects age, gender, estimated body weight (EBW), number of starts and racing performance may have on these. Methods: Sixty-three apparently healthy NSCTs in race training. Methods: Obse...
McCoy AM, Lopp CT, Kooy S, Migliorisi AC, Austin SM, Wilkins PA.Diseases affecting the internal umbilical remnant are common in foals. Ultrasound is used to diagnose abnormalities of these structures, and to monitor treatment. However, little is known about the progression of normal internal umbilical remnant regression. Objective: To document normal regression of the umbilical remnant in foals over the first 6 weeks of life. Methods: Prospective, longitudinal cohort study. Methods: Weekly ultrasound examinations were performed beginning at 1 day of age in 34 healthy Standardbred foals. The umbilical vein was measured in cross section just cranial to the...
Hue E, Orard M, Toquet MP, Depecker M, Couroucé A, Pronost S, Paillot R, Richard EA.Few data on cytokine profiles in bronchoalveolar lavage fluid (BALF) are available for racehorses with mild/moderate equine asthma (EA); cytological diagnosis being most frequently made from only one lung. The purpose of the study was to compare cytokine mRNA expressions and protein concentrations in BALF from both lungs. As part of a larger study, 250 ml saline was randomly instilled in one lung and 500 ml in the contralateral lung of 30 clinically healthy Standardbred racehorses. This procedure was repeated 72 h later, inversing the volume per lung. Cytological cut-off values for diagnosis o...
Al Abri MA, Holl HM, Kalla SE, Sutter NB, Brooks SA.The domesticated horse has played a unique role in human history, serving not just as a source of animal protein, but also as a catalyst for long-distance migration and military conquest. As a result, the horse developed unique physiological adaptations to meet the demands of both their climatic environment and their relationship with man. Completed in 2009, the first domesticated horse reference genome assembly (EquCab 2.0) produced most of the publicly available genetic variations annotations in this species. Yet, there are around 400 geographically and physiologically diverse breeds of hors...
Shono S, Gin A, Minowa F, Okubo K, Mochizuki M.Diacron-reactive oxygen metabolite (d-ROM) and biological antioxidant potential (BAP) levels in the serum of horses were measured (ponies, = 15; thoroughbred, = 31; other full-sized horses, = 7). The mean d-ROM levels in horses were significantly higher ( < 0.001) than those in dairy cattle ( = 25) and dogs ( = 31). However, d-ROM levels in horses were lower than the standard levels reported in humans. When d-ROM and BAP levels were plotted graphically, the points for horses with a disease (ringbone in 1 Japanese sports horse, cellulitis in 1 thoroughbred, melanoma in 1 Lipizzaner) fell ...
McIver VC, Tsang AS, Symonds NE, Perkins NR, Uquillas E, Dart CM, Jeffcott LB, Dart AJ.Evaluate the effect of topical 1% cannabidiol on second intention wound healing in distal limb wounds of horses. Methods: Experimental. Methods: Six Standardbred horses. Methods: A total of five 2.5 cm × 2.5 cm full thickness skin wounds were created on the dorsomedial aspect of the metacarpi of 6 horses. Wounds were contaminated with faeces on the day of wound creation. Each wound was then assigned to a treatment group; compounded 1% cannabidiol in unique manuka factor (UMF) 5 manuka honey, UMF 5 manuka honey, UMF 20 manuka honey or saline. Each treatment was applied topically daily ...
Jukic CC, Cowling NR, Perkins NR, van Eps AW, Ahern BJ.Laser salpingopharyngostomy has been used as an adjunct to primary medical therapy allowing for topical debridement, topical treatment or to potentially alter the guttural pouch environment in horses with guttural pouch disease. Objective: To evaluate the effect of a laser salpingopharyngostomy on the guttural pouch environment in healthy horses. Methods: Experimental study. Methods: In six adult Standardbred female horses, under standing sedation a stab incision was made ventral to the sternocephalicus tendon and a customised trocar inserted into the medial guttural pouch compartment. Baselin...
Klein DJ, McKeever KH, Mirek ET, Anthony TG.The athletic horse, despite being over 50% muscle mass, remains understudied with regard to the effects of exercise and training on skeletal muscle metabolism. To begin to address this knowledge gap, we employed an untargeted metabolomics approach to characterize the exercise-induced and fitness-related changes in the skeletal muscle of eight unconditioned Standardbred horses (four male, four female) before and after a 12-week training period. Before training, unconditioned horses showed a high degree of individual variation in the skeletal muscle metabolome, resulting in very few differences ...
Stokes SM, Bertin FR, Stefanovski D, Poulsen L, Belknap JK, Medina-Torres CE, Pollitt CC, van Eps AW.Continuous digital hypothermia (CDH) prevents lamellar failure in the euglycaemic hyperinsulinaemic clamp (EHC) and oligofructose (OF) laminitis models, but the mechanisms remain unclear. Objective: To evaluate the effects of CDH on lamellar energy metabolism and perfusion in healthy horses and during EHC and OF laminitis models. Methods: In vivo experiment. Methods: Archived samples were used from Standardbred geldings that received no treatment (CON) (n = 8) or underwent EHC (n = 8) or OF (n = 6) laminitis models. Both forelimbs were instrumented with a lamellar microdialysis system, a...
Stokes SM, Bertin FR, Stefanovski D, Belknap JK, Medina-Torres CE, Pollitt CC, van Eps AW.Hyperinsulinaemia is associated with the development of endocrinopathic laminitis; however, the mechanisms remain unclear. Objective: Evaluate the effects of hyperinsulinaemia on lamellar energy metabolism and perfusion during laminitis development. Methods: In vivo experiment. Methods: Eight Standardbred horses were instrumented with a microdialysis probe in the lamellae of a forelimb. A 24 hours baseline period (BASELINE) was followed by 48 hours of a continuous euglycaemic hyperinsulinaemic clamp (EHC) from 24 to 72 hours (CLAMP). Microdialysate was collected every 6 hours and analysed ...
Wilkes EJA, Heller J, Raidal SL, Woodgate RG, Hughes KJ.Information regarding parasite control practices currently used on Thoroughbred and Standardbred studs in Australia is lacking. Anthelmintic resistance (AR) is a global problem which has implications for equine health and welfare. Objective: To identify parasite control practices currently used on horse studs in Australia and investigate the frequency of use of management factors that have been associated with the likelihood of promoting or delaying AR. Methods: Questionnaire study of equine parasite control on Thoroughbred and Standardbred studs in Australia. Methods: An online questionnaire ...
Kallmyr A, Giving EM, Moen LO, Øverlie M, Holm T, David F.To describe a resection technique of the alar folds in the standing horse. Methods: Retrospective case study. Methods: Eight Standardbred racing trotters. Methods: Horses in which alar fold collapse had been diagnosed between 2017 and 2018 were included in this study. All horses underwent alar fold resection under standing sedation and regional anesthesia with a bipolar electrosurgical open sealer/divider device (LigaSure). Intraoperative and postoperative complications were recorded. A Wilcoxon signed-rank test was used to compare differences in median prize money earning pre-surgery and post...
Padalino B, Davis GL, Raidal SL.Transportation has been suggested as a risk factor for gastric ulceration in horses, but limited evidence supports this assumption. Methods: Twenty-six Standardbred, Thoroughbred, and Warmblood mares from a university teaching herd. Methods: Twelve mares were confined for 12 hours, overnight, in reproductive stocks with indwelling nasogastric tubes (NGTs) to assess pH of gastric fluid (GF). Gastric ulceration was assessed endoscopically before and after confinement. Subsequently, 26 horses were transported for 12 hours, overnight, in 2 consignments. During transportation, GF was aspirated ...
Hellings IR, Krontveit R, Øverlie M, Kallmyr A, Holm T, Fintl C.Elevated cardiac troponin T (cTnT) concentrations may provide evidence of myocardial injury but physiological post-exercise release also occurs. Reference intervals are not fully established in horses making interpretation difficult. The aims of this study were to establish an upper reference limit for serum cTnT, compare pre-and post-race serum cTnT concentrations, and to evaluate factors that may influence these in a population of healthy, race-fit Standardbred racehorses. Serum samples were collected pre- (n = 108) and 1-2 h post-racing (n = 101) and analysed using a high sensitivity-cTnT a...
Legg K, Gee E, Bolwell C, Bridges J, Rogers CW.There are limited data on the training and management practices of Standardbred trainers in New Zealand. The aims of this study were to describe the 2-year-old training practices of Standardbred trainers and to examine if there were differences in the production process between public (commercial) and amateur (licensed-to-train) trainers. An online Qualtrics survey was conducted after the 2016/7 racing season and completed by 154 Standardbred trainers, 88 (57%) of which had 2-year-olds in training. Descriptive statistics were used to describe the data stratified by public and licensed-to-train...
Gustås P, Johnston C, Roepstorff L, Drevemo S.There is a high prevalence of lameness among Standardbred trotters, most commonly caused by noninfectious joint diseases, mainly related to training and competition. In this context, impact-related shock waves transmitted through the skeleton and joints have been proposed to be one important factor in the development of osteoarthritis. The aim of the present study was to investigate the characteristic pattern of the events immediately following first contact, with a focus on the in vivo transmission of impact shock waves in the distal forelimb. Two horses were trotted by hand over a force plat...
Schroderus E, Ojala M.The aim of this study was to estimate genetic parameters for conformation measures and scores in the Finnhorse and the Standardbred foals presented in foal shows. Studied traits included height at withers and at croup, six subjectively evaluated conformation traits and overall grade. Data were from 10-year period (1995-2004) and consisted of 5821 Finnhorse foals (1-3 years old) with 7644 records and 2570 Standardbred foals (1-2 years old) with 2864 records. Variance components were estimated with REML - animal model using VCE4 program. The model included age class, year of judging, sex and...
Essén B, Lindholm A, Thornton J.Fibre characteristics and enzyme activities were determined for the gluteus, semitendinosus, vastus lateralis and triceps brachii muscles of 55 Standardbred trotters of different ages. Four fibre types (I, IIA, IIB, IIC) were demonstrated by histochemical staining of myofibrillar adenosine triphosphatase after preincubation at different pH values. Type II fibres predominated in all the muscles and the type IIA/IIB ratio was higher in horses over 5 years than in younger horses, except in the vastus in which the IIA/IIB ratio did not change with age. The vastus had the highest proportion of type...
McKeever KH, Eaton TL, Geiser S, Kearns CF, Lehnhard RA.Older horses have an increased risk of hyperthermia due to impaired cardiovascular function. While many studies have investigated thermoregulation in horses during exercise, none have investigated the effects of ageing. Objective: To test the hypothesis that there is a difference in thermoregulation during exercise and plasma volume (PV) in young and old horses. Methods: Study 1: 6 young (Y, 7.7 ± 0.5 years) and 5 old (O, 26.0 ± 0.8 years) unfit Standardbred mares (507 ± 11 kg, mean ± s.e.) ran on a treadmill (6% grade, velocity calculated to generate a work rate of 1625 watts) until core ...
Jäderkvist Fegraeus K, Velie BD, Axelsson J, Ang R, Hamilton NA, Andersson L, Meadows JRS, Lindgren G.The Swedish-Norwegian Coldblooded trotter and the heavier North-Swedish draught horse both descend from the North-Swedish horse, but the Coldblooded trotters have been selected for racing performance while the North-Swedish draught horse is mainly used for agricultural and forestry work. By comparing the genomes of Coldblooded trotters, North-Swedish draught horses and Standardbreds for a large number of single-nucleotide polymorphisms (SNPs), the aim of the study was to identify genetic regions that may be under selection for racing performance. We hypothesized that the selection for racing p...
Hurtig M, Pearce S, Warren S, Kalra M, Miniaci A.To investigate survival and function of autogenous heterotopic osteochondral grafts in a site where injuries are common. Methods: Three osteochondral grafts were harvested arthroscopically from the femoropatellar joint and transplanted to the third carpal bone (C(3)). Nine months later, histologic, histomorphometric, and biochemical comparisons were made between the transplanted grafts in C(3) and tissue adjacent to the recipient site, the opposing radial carpal bone (C(r)), the donor site in the femoropatellar joint, and the sham-operated contralateral C(3). Methods: One mixed-breed pony and ...
Tyler-McGowan CM, Golland LC, Evans DL, Hodgson DR, Rose RJ.We sought a physiological marker of overtraining in horses, using commonly practised field and laboratory tests to allow early prediction and treatment of the syndrome. Thirteen Standardbred horses were trained as follows: phase 1 (endurance, 7 weeks), phase 2 (high intensity, 9 weeks) and phase 3 (overload, 18 weeks). In phase 3 the horses were divided into 2 groups: overload training (OLT) and control (C). The OLT group exercised at greater intensities, frequencies and durations than the C group. Overtraining occurred after 31 weeks and was defined as a significant decrease in treadmill run ...
Physick-Sheard PW, Avison A, Chappell E, MacIver M.The Province of Ontario maintains a registry of racehorse deaths occurring within 60 days of a race or trial entry that provides insight into mortality rates and costs of competition. Objective: To characterise and quantify mortality and identify breed differences. Methods: Retrospective annualised cohort study. Methods: The Ontario Death Registry for 2003-2015, containing 1713 cases, was audited and information on the relationship between death and official work added. Race and trial data from industry performance databases were used to determine mortality rates according to breed, year, age...
Decloedt A, Verheyen T, Sys S, De Clercq D, van Loon G.The quantification of equine left ventricular (LV) function is generally limited to short-axis M-mode measurements. However, LV deformation is 3-dimensional (3D) and consists of longitudinal shortening, circumferential shortening, and radial thickening. In human medicine, longitudinal motion is the best marker of subtle myocardial dysfunction. Objective: To evaluate the feasibility and reliability of 2-dimensional speckle tracking (2DST) for quantifying equine LV longitudinal function. Methods: Ten healthy untrained trotter horses; 9.6 ± 4.4 years; 509 ± 58 kg. Methods: Prospective study. Re...
Kristensen L, Buhl R, Nostell K, Bak L, Petersen E, Lindholm M, Jacobsen S.The purpose of the study was to investigate whether acute strenuous exercise (1600- to 2500-m race) would elicit an acute phase response (APR) in Standardbred trotters. Blood levels of several inflammatory markers [serum amyloid A (SAA), haptoglobin, fibrinogen, white blood cell count (WBC), and iron], muscle enzymes [creatinine kinase (CK) and aspartate transaminase (AST)], and hemoglobin were assessed in 58 Standardbred trotters before and after racing. Hemoglobin levels increased and iron levels decreased 12 to 14 h after racing and haptoglobin concentrations, white blood cell counts, and i...
Taktaz Hafshejani T, Nekoei S, Vazirian B, Doosti A, Khamesipour F, Anyanwu MU.This study was undertaken to investigate molecularly the occurrence of EHV-1 and EHV-4 infection among equine population in regions, Iran. Blood samples from 53 and 37 randomly selected horses settled in Isfahan and Shahrekord, Iran, respectively, were collected. Detection of EHV-1 and EHV-4 genes in the blood samples was done using polymerase chain reaction (PCR). Out of 53 and 37 samples from Isfahan and Shahrekord, 4 (18.18%) and 3 (8.10%) were positive for PCR of EHV-1, respectively. Nine (16.98%) and 6 (16.21%) were positive for PCR of EHV-4, while 6 (11.32%) and 3 (8.10%) were positive f...
Sackman JE, Houpt KA.Temperament can be defined as innate properties of the nervous system, whereas personality includes the complex behavioral traits acquired through life. Association between personality and behavior is important for breeding, selection, and training of horses. For the first time, we evaluated if equine personality components previously identified in Japan and Europe were consistent when applied to American horses. We examined the association of personality with breed, age, sex, management, training, stereotypies, and misbehaviors. The owner directed personality survey consisted of 25 questions....
Zucca E, Ferrucci F, Croci C, Di Fabio V, Zaninelli M, Ferro E.The aim of this study was to obtain echocardiographic measurements and establish reference ranges for 14 parameters in Standardbred racehorses in training. Background: Several studies have been published about cardiac measurements in Thoroughbreds, Standardbreds, National Hunt horses, Warmbloods and ponies; however, not all parameters have been published for the Standardbred trotter in training. Methods: Thirty normal Standardbred racehorses in training were assessed by two-dimensional echocardiography (2-D) and M-mode echocardiography using standardized imaging planes. Mean values, standard d...
Laverty S, Lacourt M, Gao C, Henderson JE, Boyde A.We studied changes in articular calcified cartilage (ACC) and subchondral bone (SCB) in the third carpal bones (C3) of Standardbred racehorses with naturally-occurring repetitive loading-induced osteoarthritis (OA). Two osteochondral cores were harvested from dorsal sites from each of 15 post-mortem C3 and classified as control or as showing early or advanced OA changes from visual inspection. We re-examined X-ray micro-computed tomography (µCT) image sets for the presence of high-density mineral infill (HDMI) in ACC cracks and possible high-density mineralized protrusions (HDMP) from the ACC...
Schwarzwald CC, Schober KE, Berli AS, Bonagura JD.Noninvasive assessment of left-ventricular (LV) function is clinically relevant, but is incompletely studied in horses. Objective: To document the feasibility, describe the techniques, and determine the reliability of 2D speckle tracking (2DST) for characterization of LV radial and circumferential wall motion in horses. Methods: Three Standardbreds, 3 Thoroughbreds; age 8-14 years; body weight 517-606 kg. Methods: Observational study. Repeated 2-dimensional echocardiographic examinations were performed in unsedated horses by 2 observers and subsequently analyzed by 2DST. Test reliability was d...
Lo Feudo CM, Stucchi L, Conturba B, Stancari G, Zucca E, Ferrucci F.Poor performance is a multifactorial syndrome of racehorses, commonly associated with subclinical disorders, which can be diagnosed by exercise testing. Objective: Describe the prevalence of medical causes of poor performance in Standardbreds unassociated with lameness, and evaluate their relationships with fitness variables measured by exercise treadmill test. Methods: Hospital population of 259 nonlame Standardbred trotters referred for poor performance. Methods: The horses' medical records were retrospectively reviewed. Horses underwent a diagnostic protocol including resting examination, p...
Kitson-Piggot AW, Prescott JF.Sera from Thoroughbred and Standardbred horses in southwest Ontario were tested for antibody to seven Leptospira interrogans serovars (autumnalis, bratislava, canicola, grippotyphosa, hardjo, icterohaemorrhagiae, pomona), using the microscopic agglutination test. There was significantly higher seroprevalence of bratislava than of other serovars, in which prevalence was low. Seroprevalence of bratislava increased significantly with age; only 5% of two to three year old horses had titers greater than or equal to 1:80 compared to 52% of horses older than seven years. Eight of 16 foals from two fa...
Slack J, Stefanovski D, Madsen TF, Fjordbakk CT, Strand E, Fintl C.The significance of cardiac arrhythmias and their possible association with upper airway obstruction are frequently considered in the clinical investigation of poor performance. The specific aims of this retrospective study of a group of poorly performing Standardbred and Norwegian-Swedish Coldblooded trotters were to: (1) describe the overall frequency and frequency distributions of arrhythmias; (2) describe arrhythmia characteristics including percent prematurity, relative recovery cycle lengths and QRS morphology; (3) describe variability of normal RR intervals; and (4) explore possible ass...
Velie BD, Fegraeus KJ, Solé M, Rosengren MK, Røed KH, Ihler CF, Strand E, Lindgren G.Although harness racing is of high economic importance to the global equine industry, significant genomic resources have yet to be applied to mapping harness racing success. To identify genomic regions associated with harness racing success, the current study performs genome-wide association analyses with three racing performance traits in the Norwegian-Swedish Coldblooded Trotter using the 670 K Axiom Equine Genotyping Array. Following quality control, 613 horses and 359,635 SNPs were retained for further analysis. After strict Bonferroni correction, nine genome-wide significant SNPs were id...
Birks EK, Shuler KM, Soma LR, Martin BB, Marconato L, Del Piero F, Teleis DC, Schar D, Hessinger AE, Uboh CE.The incidence and severity of exercise-induced pulmonary haemorrhage (EIPH) in the 2 most commonly raced horse breeds, Thoroughbreds (TB) and Standardbreds (STD), were studied, with particular interest in the possible influence of frusemide (F) and/or the breed (or running gait) on EIPH. The appearance of blood within the trachea was semi-quantified using a published 5-point system, with zero assigned when no blood was observed, and numbers 1-4 assigned with increasing amounts of blood. Considering each endoscopic examination as a separate event, approximately 75% of the postrace endoscopic ex...
Lindgren G, Sandberg K, Persson H, Marklund S, Breen M, Sandgren B, Carlstén J, Ellegren H.A primary male autosomal linkage map of the domestic horse (Equus caballus) has been developed by segregation analysis of 140 genetic markers within eight half-sib families. The family material comprised four Standardbred trotters and four Icelandic horses, with a total of 263 offspring. The marker set included 121 microsatellite markers, eight protein polymorphisms, five RFLPs, three blood group polymorphisms, two PCR-RFLPs, and one single strand conformation polymorphism (SSCP). One hundred markers were arranged into 25 linkage groups, 22 of which could be assigned physically to 18 different...
Tanner JC, Rogers CW, Firth EC.To investigate the association between attainment of training milestones by 2-year-old horses with racing outcomes in a population of Standardbred racehorses in New Zealand. Methods: Retrospective records of the 2001/2002-born Standardbred foals were obtained. The three training milestones used were: registered with a trainer, entered in a trial, and competed in a race. The racing outcomes were length of career in years raced and number of race starts, and total earnings. Cox regression analysis was used to assess the association between attainment of the three milestones by 2-year-olds and th...
Lindåse S, Nostell K, Bröjer J.An oral sugar test (OST) using Karo® Light Corn Syrup has been developed in the USA as a field test for the assessment of insulin dysregulation in horses but the syrup is not available in Scandinavian grocery stores. The aim of the study was to compare the results of a modified OST between horses with equine metabolic syndrome (EMS) and healthy horses using a Scandinavian commercially available glucose syrup (Dansukker glykossirap). In addition, the effect of breed and the repeatability of the test were evaluated. In the present study, clinically healthy horses (7 Shetland ponies, 8 Icelandic...
Kohn CW, Knight D, Hueston W, Jacobs R, Reed SM.Immunoglobulin G, IgM, and IgA concentrations were measured in serum collected from 36 Standardbred mares within 12 hours of foaling, in colostrum collected within 6 hours of foaling, and in serum collected from foals 24 to 48 hours after birth. In serum collected from mares after parturition, mean concentrations of IgG, IgM, and IgA were 2,463.9 +/- 1,337.3 mg/dl, 136.4 +/- 218 mg/dl, and 305.2 +/- 237.5 mg/dl, respectively. In serum from foals, mean concentrations of IgG, IgM, and IgA were 1,953.3 +/- 1,635 mg/dl, 33.8 +/- 30.4 mg/dl, and 58.4 +/- 42.2 mg/dl, respectively. In colostrum, mean...
Bailey E.336 Standardbred mares and 334 Thoroughbred mares in the vicinity of Lexington, Kentucky, were lymphocyte typed for 11 allelic antigenic specificities of the equine lymphocyte antigen (ELA) system. The Standardbred mares were divided into a population of pacers and a population of trotters. Substantial differences in ELA gene frequencies were found between the 3 groups. When the distribution of antigens within populations were compared to Hardy-Weinberg equilibrium expectations, relatively good agreement was found.
Mariella J, Pirrone A, Gentilini F, Castagnetti C.The purposes of this study were to determine physiological changes occurring in hematologic and biochemical parameters in mares between the last month of gestation and the first week after parturition. If a significant change was observed with respect to the reference interval of an adult horse, a further aim of the study was to establish different reference intervals. Blood samples were collected from 62 healthy pregnant Standardbred mares. Seventeen nonpregnant and nonlactating mares were used as a control group. In pregnant mares, blood sampling was conducted every three days from 1 month b...
Lamprecht ED, Williams CA.Objectives were to evaluate effects of (1) repetitive arthrocentesis on biomarkers of inflammation (prostaglandin E(2), PGE(2)) and aggrecan synthesis (chondroitin sulfate-846; CS) in synovial fluid (SF); (2) exercise and superoxide dismutase (SOD) supplementation on biomarkers of inflammation, antioxidant status, and aggrecan synthesis, in horses. Preliminary trial. Standardbreds underwent four arthrocentesis procedures within 48 h and exhibited elevated CS and no changes in PGE(2). Exercise trial. this randomized crossover design used twelve Standardbred mares which received either treatment...
Kinnunen S, Oksala N, Hyyppä S, Sen CK, Radak Z, Laaksonen DE, Szabó B, Jakus J, Atalay M.Several micronutrient supplementation strategies are used to cope with oxidative stress, although their benefits have recently been questioned. The aim of the present study was to examine the effects of DL-alpha-lipoic acid (LA) in response to acute exercise and during recovery in horses. Six standardbred trotters were tested on the treadmill before and after 5-week LA supplementation (25 mg/kg body weight/day). According to electron paramagnetic resonance measurements, strenuous aerobic exercise increased significantly free radical formation in the gluteus medius muscle, which was prevented b...
Jacquet S, Robert C, Valette JP, Denoix JM.The objective of this study was to evaluate the spontaneous evolution of radiological findings (RF) indicative of juvenile osteochondral conditions (JOCC) in a field study. A radiographic survey was performed at the age of 6 and 18months in 321 young horses from three breeds (French Trotter Standardbred, Selle-Français Warmblood and Thoroughbred). Each RF identified at 6months was re-evaluated at 18months, and classified as (1) disappeared, (2) improved, (3) stable, (4) deteriorated or (5) new when it was not identified at 6months. Only 32.3% of all RF identified at the age of 6months were st...
