Horse racing is a competitive equestrian sport involving horses ridden by jockeys over set distances, often on flat tracks or over obstacles. It is characterized by a variety of race types, including thoroughbred, harness, and steeplechase, each with distinct rules and traditions. The sport emphasizes speed, stamina, and strategy, with races typically categorized by distance, surface type, and horse age or breed. Horse racing plays a significant role in the equine industry, influencing breeding, training, and veterinary care practices. This page compiles peer-reviewed research studies and scholarly articles that explore the physiological demands, training methodologies, and health considerations associated with horse racing.
Crawford KL, Finnane A, Phillips CJC, Greer RM, Woldeyohannes SM, Perkins NR, Kidd LJ, Ahern BJ.Musculoskeletal injuries (MSI) continue to affect Thoroughbred racehorses internationally. There is a strong interest in developing training and management strategies to reduce their impact, however, studies of risk factors report inconsistent findings. Furthermore, many injuries and fatalities occur during training rather than during racing, yet most studies report racing data only. By combining racing and training data a larger exposure to risk factors and a larger number of musculoskeletal injuries are captured and the true effect of risk factors may be more accurately represented. Furtherm...
Boorman S, Hofmeister EH, Ross MW, Ralston S, Bell G, Mackie S, Ortved K.To determine the influence of clinical osteochondrosis (OC) on the short-term (2, 3, and 4-year-old) and long-term racing performance and longevity of standardbred racehorses. Methods: Retrospective case-control study. Methods: Standardbred racehorses from a single breeding farm born between 2009 and 2017 that survived to racing age (n = 2711). Three hundred eighty-two (14%) horses were OC-affected (829 lesions confirmed arthroscopically during surgical treatment), and 2329 (86%) horses were nonaffected. Methods: Racing performance data were obtained from an online database and evaluated with ...
Ravanetti P, Hamon M, Lechartier A, Zucca E.Surgical repair of unicortical fractures of the distal condyles of the third metacarpal/metatarsal bones (MCIII/MTIII) has been described. In the present case, a bioabsorbable screw was used to stabilize a unicortical fracture in the palmar aspect of the medial condyle of MCIII in a National Hunt Thoroughbred racehorse. The clinical, radiographic, and magnetic resonance imaging findings before and after surgery were recorded. Eighteen weeks after surgery, the lameness had resolved and the bone surrounding the fracture had recovered its normal architecture. One year after surgery, the horse was...
Witkowska-Piłaszewicz O, Grzędzicka J, Seń J, Czopowicz M, Żmigrodzka M, Winnicka A, Cywińska A, Carter C.Assuring a high level of animal welfare is a critical aspect of contemporary animal husbandry. Equine athletes begin their careers at a very young age when they are still developing and they are both physically and mentally immature. Lack of scientific knowledge of the stress related to horse racing impedes the development of optimal training programs to attain equilibrium between the best sport results and optimal welfare. This study aimed to determine the influence of the intensity and type of physical activity on peripheral blood cortisol concentration. Thirty untrained Arabians, 9 enduranc...
Crawford KL, Finnane A, Greer RM, Phillips CJC, Woldeyohannes SM, Perkins NR, Ahern BJ.There is international public concern regarding retirement of racehorses, including the reason for retirement and the outcome for horses after racing. However, there are currently no prospective studies investigating these factors. A recent independent inquiry in Queensland, Australia, highlighted that the true outcomes for horses after retirement from racing are largely unknown. Furthermore, there are currently no measures to monitor the outcome for racehorses and their welfare once they have left the care of the trainer. This study investigated these gaps in knowledge through a weekly survey...
Cheung HW, Wong KS, To NS, Bond AJ, Farrington AF, Prabhu A, Curl P, Wan TSM, Ho ENM.Selective androgen receptor (AR) modulators (SARMs) are potent anabolic agents with a high potential of misuse in horseracing and equestrian sports. In this study, we applied label-free proteomics to discover plasma protein biomarkers in geldings (castrated horses) after administration with a popular SARM named RAD140. Tryptic peptides were prepared from plasma samples and analyzed by nano-flow ultrahigh-performance liquid chromatography-high-resolution tandem mass spectrometry (nano-UHPLC-HRMS/MS) using data-independent acquisition (DIA) method. Orthogonal projection on latent structure-discr...
Di Tocco J, Sabbadini R, Raiano L, Fani F, Ripani S, Schena E, Formica D, Massaroni C.In recent years, wearable devices for physiological parameter monitoring in sports and physical activities have been gaining momentum. In particular, some studies have focused their attention on using available commercial monitoring systems mainly on horses during training sessions or competitions. Only a few studies have focused on the jockey's physiological and kinematic parameters. Although at a glance, it seems jockeys do not make a lot of effort during riding, it is quite the opposite. Indeed, especially during competitions, they profuse a short but high intensity effort. To this extend, ...
Parkes RSV, Pfau T, Weller R, Witte TH.During racing, injury is more likely to occur on a bend than on a straight segment of track. This study aimed to quantify the effects of galloping at training speeds on large radius curves on stride parameters and limb lean angle in order to assess estimated consequences for limb loading. Seven Thoroughbred horses were equipped with a sacrum-mounted inertial measurement unit with an integrated GPS, two hoof-mounted accelerometers and retro-reflective markers on the forelimbs. Horses galloped 2-4 circuits anticlockwise around an oval track and were filmed at 120 frames per second using an array...
Riggs CM, Thompson SL, So YM, Wong JKY, Wan TSM, Robinson P, Stewart BD, Ho ENM.Administration of bisphosphonates, including tiludronic acid, to Thoroughbred racehorses below 3 and a half years of age is prohibited in most racing jurisdictions. Objective: To determine if evidence of administration of tiludronic acid could be obtained from analysis of blood and urine samples beyond 40 days after administration. Methods: Retrospective cohort. Methods: Horses maintained in a highly controlled environment and treated with Tildren®a were selected from clinical records. Twenty-four horses were identified, 21 of which were still in race training. Blood and urine samples were c...
Ayodele BA, Hitchens PL, Wong ASM, Mackie EJ, Whitton RC.Proximal sesamoid bone fractures are common catastrophic injuries in racehorses. Understanding the response of proximal sesamoid bones to race training can inform fracture prevention strategies. Objective: To describe proximal sesamoid bone microstructure of racehorses and to investigate the associations between microstructure and racing histories. Methods: Cross-sectional. Methods: Proximal sesamoid bones from 63 Thoroughbred racehorses were imaged using micro-computed tomography. Bone volume fraction (BVTV) and bone material density (BMD) of the whole bone and four regions (apical, midbody d...
Toma M, Pandya YH, Dongre D, Nizich M.There is a multitude of whips and riding crops. It is assumed that the whip in Thoroughbred racing must be padded and designed to be energy-absorbing. The new whips have a cushion made of softer material to be presumably more ethical when used on the horses. This study quantifies the forces exerted on a flat target plate using three different riding crops. The goal is to comparatively determine which one is less likely to leave a mark on the equine skin when the same bending level of the crop cores is achieved. Counterintuitively, it is shown that the riding crop even when its popper is made o...
Mizobe F, Takahashi Y, Kusano K.Jockey safety is of paramount importance from the standpoint of welfare and public perception. Thus, an understanding of the epidemiology and associated risk factors is necessary to implement measures to reduce the jockey falls (JFs) and jokey injuries (JIs). This descriptive epidemiological study investigated the occurrence of JFs and JIs in 715,210 and 25,183 rides in flat and jump races, respectively, from 2003 to 2017. In flat races, the incidence rates of JFs and JIs were 1.4 and 0.6 per 1,000 rides, respectively. In jump races, they were 44.4 and 18.1 per 1,000 rides, respectively. In fl...
Tozaki T, Ohnuma A, Kikuchi M, Ishige T, Kakoi H, Hirota KI, Hamilton NA, Kusano K, Nagata SI.Gene doping is prohibited in horseracing and equestrian sports. In previous studies, we developed non-targeted transgene and genome editing detection methods based on whole genome resequencing (WGR) using genomic DNA extracted from whole blood. In this study, we aimed to develop a WGR method using DNA extracts from hair roots. Hair roots are a preferred substrate because their collection is less invasive than blood collection. Hair is also easier to store for long periods of time. Although almost all genomic DNA extracted from hair root samples stored for years at room temperature was degraded...
Matheson A, Regmi SC, Jay GD, Schmidt TA, Scott WM. Local biological and biomechanical-stimuli modulate proteoglycan-4 secretion within synovial joints. For the horse, changes to proteoglycan-4 concentration and function are notable in acute joint injury and osteoarthritis. Proteoglycan-4 (also known as Lubricin) is present in the blood, however the effect of exercise on equine serum levels is unknown. The overall objective of this study was, therefore, to investigate the effect of intense exercise on serum proteoglycan-4 in thoroughbred horses. Samples of blood were taken from thoroughbreds ( = 12) during a chuckwagon racing event (Alberta, ...
O'Brien TJ, Rosanowski SM, Mitchell KD, Carrick JB, Butt TD, Adkins AR.There is little consensus on factors associated with survival in foals with septic arthritis and limited data on long-term racing performance of Thoroughbred foals treated for septic arthritis. A more thorough understanding of short- and long-term outcome is necessary to help inform owners, and subsequently guide treatment. Objective: To investigate factors associated with survival, and to analyse racing performance of foals with septic arthritis compared with their maternal siblings. Methods: Retrospective cohort and a case-control study. Methods: Veterinary clinical records of Thoroughbred f...
Shnaiderman-Torban A, Navon-Venezia S, Paitan Y, Archer H, Abu Ahmad W, Bonder D, Hanael E, Nissan I, Zizelski Valenci G, Weese SJ, Steinman A.We aimed to investigate the prevalence, molecular epidemiology and prevalence factors for Extended Spectrum β-Lactamase-producing Enterobacteriaceae (ESBL-E) shedding by race horses. A cross-sectional study was performed involving fecal samples collected from 169 Thoroughbred horses that were housed at a large racing facility in Ontario, Canada. Samples were enriched, plated on selective plates, sub-cultured to obtain pure cultures and ESBL production was confirmed. Bacterial species were identified and antibiotic susceptibility profiles were assessed. E. coli sequence types (ST) and ESBL gen...
Mercier Q, Aftalion A.The objective of this work is to provide a mathematical analysis on how a Thoroughbred horse should regulate its speed over the course of a race to optimize performance. Because Thoroughbred horses are not capable of running the whole race at top speed, determining what pace to set and when to unleash the burst of speed is essential. Our model relies on mechanics, energetics (both aerobic and anaerobic) and motor control. It is a system of coupled ordinary differential equations on the velocity, the propulsive force and the anaerobic energy, that leads to an optimal control problem that we sol...
Ricard A, Duluard A.The aim was to disentangle gait characteristics from other qualities needed for racing performances with a genomic analysis of French trotters (FT). A sample of 1,390 horses were recruited, from which 46% were genotyped with Illumina chip of 54,602 SNPs, 49% with Affymetrix chip of 670,806 SNPs and 586 had a completed questionnaire on trotting technique. Racing performances cover the period 1996 to 2018. There were 252,368 FT-born; 96,617 qualified and 83,962 which participated in a race. After quality control, 377,611 SNPs were retained and imputed. Questionnaire described trotting technique ...
Massie SL, Bezugley RJ, McDonald KJ, Leguillette R.The prevalence and severity of cardiac arrhythmias in healthy racehorses undergoing competition is not well defined. The aim was to characterize arrhythmias in Thoroughbreds participating in official Chuckwagon races and to determine normal beat-to-beat (R-R) variability during supramaximal exercise. Electrocardiograph (ECG) recordings were obtained during pre-race, race, and active-recovery from 82 clinically healthy Thoroughbreds. ECG recordings were analyzed for arrhythmias and mean percent R-R deviation. Plasma lactate and high-sensitivity troponin (hs-cTnT) were also measured. Fifty-two E...
Morrice-West AV, Hitchens PL, Walmsley EA, Stevenson MA, Wong ASM, Whitton RC.With each stride, galloping horses generate large skeletal loads which influence bone physiology, and may contribute to musculoskeletal injury. Horse speed and stride characteristics are related, but the usefulness of using horse speed and distance travelled as a proxy for stride characteristics is unknown. Objective: We aimed to determine stride characteristics, their variance and their relationship with speed in horses performing maximally. Methods: Retrospective cross-sectional analysis of archived data. Methods: Stride characteristics obtained using GPS and inertial sensors in Thoroughbred...
Buhl R, Nissen SD, Winther MLK, Poulsen SK, Hopster-Iversen C, Jespersen T, Sanders P, Carstensen H, Hesselkilde EM.Limited information is available on paroxysmal atrial fibrillation (PAF) in the horse. Indeed, undiagnosed PAF could result in poor performance. Due to the intermittent occurrence, PAF is difficult to diagnose. However, implanting a small ECG device (implantable loop recorder, ILR) subcutaneously, allows the continuous and automatic detection of PAF. Objective: The aim was to investigate the potential of ILRs as a tool for diagnosing PAF in horses with poor performance. Methods: Prospective field study. Methods: Twelve racing Standardbred trotters with intermittent reduced performance (mean ag...
Horan K, Kourdache K, Coburn J, Day P, Brinkley L, Carnall H, Harborne D, Hammond L, Millard S, Pfau T.Riding racehorses is a high-risk profession and optimizing safety alongside performance is paramount. Horseshoes play a critical role in providing traction with the ground surface and are therefore a major determinant of safety. However, the subjective perceptions of expert riders influence attitudes towards using different shoes and must be taken into consideration before any changes may be implemented. This study used a questionnaire-based method to evaluate jockey opinion of four shoeing conditions (aluminum, steel, GluShu, and barefoot) trialed at gallop over turf and artificial surfaces. ...
Johnson E, van Heemst J, Benavides J, Gray B.Etizolam is a benzodiazepine analogue that is approved for use in Japan, Italy and India but has recently appeared as a nonapproved product on the illicit drug market in Europe and North America. Etizolam was identified in a crystalline material seized at a Kentucky racetrack, raising concerns that this drug may have been used in racing. The aim of this study was to characterize the metabolism and excretion of etizolam in horses to generate information on its disposition and to incorporate the correct urinary and serum target analytes into anti-doping screening procedures. Etizolam was adminis...
Witkowska-Piłaszewicz O, Maśko M, Domino M, Winnicka A.In horse racing the most acceptable way to objectively evaluate adaptation to increased exertion is to measure lactate blood concentration. However, this may be stressful for the horse, therefore, a simple, noninvasive procedure to monitor race progress is desirable. Forty Thoroughbreds attended race training, with blood samples collected at rest, immediately after, and 30 min after exercise. The lactate concentration was determined 60 s after blood collection using an Accusport. Thermal imaging of the neck and trunk areas was performed following international veterinary standards from a dista...
Bailey SR, Forbes G, Selvadurai N, McLarney K, Jones S, Steel CM.The administration of alkalinising agents including bicarbonate is of concern to racing authorities because resultant alkalosis may enhance performance and interfere with the detection of drugs in post-race urine. A threshold for total carbon dioxide (TCO ) of 36.0 mmol/L in plasma (with action limit of 37.0 mmol/L) has been set. Serial dosing of sodium bicarbonate has gained popularity in human athletes but has not been studied in horses previously. Sodium bicarbonate (200 g per horse) and 60 g of an electrolyte-vitamin complex was administered in 2-L water via nasogastric intubation to five ...
Crawford KL, Finnane A, Greer RM, Phillips CJC, Woldeyohannes SM, Perkins NR, Ahern BJ.Musculoskeletal injuries (MSI) remain a concerning cause of racehorse morbidity and mortality with important ethical and welfare consequences. Previous research examining risk factors for MSI report inconsistent findings. Age is thought to affect MSI risk, but, to date, there have been no prospective studies comparing MSI in two-year-old versus older horses. This study aimed to: (1) determine the incidence of MSI for two-year-old and older horses, and whether this was affected by training track, season, or rainfall, and (2) determine the types of MSI affecting two-year-old and older horses, an...
Ebert M, Moore-Colyer MJS.The aim of this study was to estimate the energy requirements of Thoroughbred racehorses in active training for flat racing. Twenty-two Thoroughbred racehorses in England were measured over periods from 6 to 15 wk, which included periods of active race training and temporarily reduced training. Energy intake was determined by measuring daily feed consumption. Energy output was measured using heart rate monitors during 730 training sessions, relating heart rate (HR) to oxygen consumption (VO2) and converting VO2 to energy. Field maintenance requirements were calculated by deducting the marginal...
Thompson K, McManus P, Stansall D, Wilson BJ, McGreevy PD.The idea that whip use is critical to thoroughbred racing integrity is culturally entrenched but lacks empirical support. To test the longstanding beliefs that whip use aids steering, reduces interference, increases safety and improves finishing times, we conducted a mixed-method analysis of 126 race reports produced by official stewards of the British Horseracing Authority, representing 1178 jockeys and their horses. We compared reports from 67 "Hands and Heels" races, where whips are held but not used (whipping-free, WF), with 59 reports from case-matched races where whipping was permitted (...
Marr CM, Franklin S, Garrod G, Wylie C, Smith L, Dukes-McEwan J, Bright J, Allen K.Exercise-associated cardiac rhythm disturbances are common, but there is a lack of evidence-based criteria on which to distinguish clinically relevant rhythm disturbances from those that are not. Objective: To describe and characterise rhythm disturbances during clinical exercise testing; to explore potential risk factors for these rhythm disturbances and to determine whether they influenced future racing. Methods: Retrospective cohort using a convenience sample. Methods: Medical records were reviewed from two clinical services to identify horses with poor performance and/or respiratory noise ...
Sugiura T, Shimada K.A sero-epizootiological survey was conducted for Japanese encephalitis virus (JEV) and Getah virus (GeV) at 10 to 20 regional horse race tracks from 1991 to 1997 in Japan. It was observed that geometrical mean (GM) antibody titer to JEV and GeV was 10 to 50 times higher than others at several race courses (RCs) almost every year. Of them, several race horses showing high antibody titer, which were suggested to be infected with the virus, were also observed in this survey. These data suggested that the viruses have spread among race horses almost every year in Japan, although, fortunately, no h...
Kiryu K, Machida N, Kashida Y, Yoshihara T, Amada A, Yamamoto T.Five racehorses in apparently normal condition succumbed to sudden cardiac death (SCD) during or shortly after intensive training exercise. Cardiopathologic examination was performed. In 1 of the 5 horses, the use of an electrocardiogram (ECG) recording taken continuously for 440 sec enabled us to analyze some of the arrhythmias in the terminal event of SCD. The ECG tracing exhibited the R-on-T phenomenon following a pair of ventricular premature contractions (VPCs). The phenomenon rapidly degenerated into ventricular fibrillation, which led to cardiac arrest. In all 5 horses cardiopathologic ...
Yamazaki M, Kusano K, Ishibashi T, Kiuchi M, Koyama K.Upon intensive, exhaustive exercise, exercise-induced reactive oxygen species may exceed the antioxidant defence threshold, consequently resulting in muscular damage or late-onset chronic inflammation. Recently, the therapeutic antioxidant and anti-inflammatory effects of molecular hydrogen (H2) for human rheumatoid arthritis have been demonstrated. However, it is also important to clarify the effects of administrating H2 in large animals other than humans, as H2 is thought to reach the target organ by passive diffusion upon delivery from the blood flow, indicating that the distance from the a...
Lester GD, Smith RL, Robertson ID.To compare the effects of oral administration of omeprazole and ranitidine on gastric squamous ulceration in Thoroughbreds in race training. Methods: Modified crossover study. Methods: 60 Thoroughbreds in race training with gastric squamous mucosal ulceration. Methods: Horses were randomly allocated into 3 groups. Group 1 received no treatment for 28 days followed by administration of omeprazole (4 mg/kg [1.8 mg/lb], PO, once daily) for 28 days; group 2 received omeprazole (4 mg/kg, PO, once daily) for 28 days followed by no treatment for 28 days; and group 3 received ranitidine (6.6 mg/kg [3....
Ropka-Molik K, Stefaniuk-Szmukier M, Z Ukowski K, Piórkowska K, Bugno-Poniewierska M.It has been found that Arabian and Thoroughbred horses differ in muscle fiber structure and thus in physiological changes occurring in muscles during exercise. The aim of the present study was to identify the global gene expression modifications that occur in skeletal muscle following a training regime to prepare for flat racing. Whole transcriptomes of muscle (gluteus medius) were compared between three time points of tissue collection: T (untrained horses), T (horses after intense gallop phase), and T (horses at the end of racing season), 23 samples in total. The numerous groups of exercise-...
Cogger N, Evans DL, Hodgson DR, Reid SW, Perkins N.To describe the incidence rate of musculoskeletal (MS) injuries and investigate the factors that influence recovery from MS injury in young Thoroughbred horses in Australia. Methods: Training and injury data were collected at fortnightly intervals from 14 trainers in New South Wales. Incidence rates were calculated for initial injuries stratified by age-class and sex. Survival analysis methods were used to investigate the time to recovery after the first MS injury (measured as a start in a race or barrier trial). Results: For the 248 racehorses enrolled, there were 428 injuries recorded; 2-yea...
Perkins NR, Reid SW, Morris RS.To describe patterns in training, racing, and general health in a population of Thoroughbred racehorses in New Zealand. Methods: A longitudinal study was designed to collect data on horses training under the care of 20 selected trainers from 20 different stables and five regional training venues in the mid to lower regions of the North Island. Data were collected from trainers at approximately monthly intervals between October 1997 and July 2000, and electronic data containing race and trial results for all starts in New Zealand for the same time period were obtained from New Zealand Thoroughb...
Pusterla N, Mapes S, Akana N, Barnett C, MacKenzie C, Gaughan E, Craig B, Chappell D, Vaala W.The objective of the present case-control study was to determine prevalence factors associated with the detection of equine herpesvirus type 1 (EHV-1) by quantitative PCR (qPCR) in horses presented to veterinarians with clinical signs related to an upper respiratory tract infection and/or acute onset of neurological disease from March 2008 to December 2014. Nasal secretions and whole blood from 4228 equids with acute onset of fever, respiratory signs and/or neurological deficits were tested by qPCR for EHV-1. Categorical analyses were performed to determine the association between observations...
Clarke EJ, Lima C, Anderson JR, Castanheira C, Beckett A, James V, Hyett J, Goodacre R, Peffers MJ.Equine osteoarthritis is a chronic degenerative disease of the articular joint, characterised by cartilage degradation resulting in pain and reduced mobility and thus is a prominent equine welfare concern. Diagnosis is usually at a late stage through clinical examination and radiographic imaging, whilst treatment is symptomatic not curative. Extracellular vesicles are nanoparticles that are involved in intercellular communication. The objective of this study was to investigate the feasibility of Raman and Optical Photothermal Infrared Spectroscopies to detect osteoarthritis using plasma-derive...
Hintz RL.Criteria used to measure performance, environmental factors that influence performance and estimates of heritability are needed to estimate genetic differences. Published heritability estimates of various measures of performance in the horse are summarized. The average heritability estimates of pulling ability and cutting ability are .25 and .04, respectively. Heritability estimates are .18, .19 and .17 for log of earnings from jumping, 3-day event and dressage performance, respectively. Heritability estimates of performance rates, log of earnings, earnings, handicap weight, best handicap weig...
Strand E, Fjordbakk CT, Holcombe SJ, Risberg A, Chalmers HJ.Dynamic laryngeal collapse (DLC) associated with poll flexion is a newly diagnosed upper respiratory tract obstructive disorder that causes poor racing performance. Objective: To determine if Norwegian Coldblooded Trotters (NCTs) affected with DLC associated with poll flexion differ from normal, elite NCTs based on simple airway mechanics measurements. Methods: Five normal elite NCTs and 6 NCTs diagnosed previously with DLC underwent treadmill videoendoscopy while tracheal pressures were measured continuously. Alternating head positions were used such that horses were exercised with free head ...
Sweeney CR, Maxson AD, Soma LR.The frequency of upper respiratory tract abnormalities was determined in a selected population of racing Thoroughbreds. The prevalence of pharyngeal lymphoid hyperplasia was 34.2%; left laryngeal hemiplegia was 1.8%; and epiglottic entrapment was 0.74%. Excluding pharyngeal lymphoid hyperplasia and tracheal exudate, 3.7% of the population examined had upper respiratory tract abnormalities.
Mohammed HO, Hill T, Lowe J.A case-control study was conducted on Thoroughbred horses to identify factors associated with the risk of breakdown on racetracks. A total of 310 cases (breakdowns) were identified from the Horse Identification Department records kept by the chief examining veterinarian of New York Racing Association. For each case, two control horses were selected randomly from the Daily Racing Form Inc. records. Multiple logistic regression analysis was used to identify and quantify the risk of factors associated with breakdown, while simultaneously controlling for the effect of other putative factors. Facto...
Harrison SP, Turrion-Gomez JL.The mitochondrial DNA (mtDNA) molecule, carrying genes encoding for respiratory chain enzymes, is a primary candidate for demonstrating associations between genotype and athletic performance in mammalian species. In humans, variation at seven protein encoding mitochondrial loci has been implicated in influencing fitness and performance characteristics. Although thoroughbred horses are selected for racing ability, there have not been any previous reported associations between genotypes and racecourse performance. The multi-factorial nature of the inheritance of racing ability is an obvious comp...
Phillips W, Giguère S, Franklin RP, Hernandez J, Adin D, Peloso JG.Cardiac troponin I (cTnI), a myocardial polypeptide, is a highly sensitive and specific biomarker of myocardial injury in people and dogs. The structure of cTnI is highly conserved across species, and equine myocardium has high reactivity with human immunoassays. The purpose of this study was to describe cTnI concentrations in normal pastured and race-training Thoroughbred horses. Ten horses on pasture and 10 horses in race training were studied. Horses were considered normal on the basis of physical examination, training performance, electrocardiography (ECG), and echocardiography. Serum cTnI...
Parkes RS, Witte TH.The equine limb has evolved for efficient locomotion and high-speed performance, with adaptations of bone, tendon and muscle. However, the system lacks the ability seen in some species to dynamically adapt to different circumstances. The mechanical interaction of the limb and the ground is influenced by internal and external factors including fore-hind mass distribution, lead limb, moving on a curve, shoeing and surface properties. It is unclear which of the components of limb loading have the largest effect on injury and performance but peak load, impact and vibration all play a role. Factors...
Pool RR, Meagher DM.Many lesions of the musculoskeletal system of racing horses are either acute traumatic lesions or are chronic biomechanically induced lesions that become suddenly unstable and provoke acute clinical signs. The latter lesions along with those of DJD are much more common and are of much greater overall economic importance to the racing industry than are the acute traumatic injuries. Chronic biomechanical lesions occur at predictable sites and are the result of an imbalance between repetitive microtrauma sustained in athletic performance and adaptive repair mechanisms of skeletal tissues. The dis...
Pollock PJ, Reardon RJ, Parkin TD, Johnston MS, Tate J, Love S.There are potential advantages to imaging the upper portion of the respiratory tract (URT) of horses during ridden exercise. With the advent of a wireless endoscope, this is now possible. However, there has been no detailed validation of the technique and findings have not been compared to ridden speed. Objective: To assess the combined use of a Dynamic Respiratory Scope (DRS) and global positioning system (GPS) receiver for examining the URT of a group of Thoroughbred racehorses randomly selected from a single flat racehorse training establishment. Methods: Horses were selected randomly from ...
Lo Feudo CM, Stucchi L, Stancari G, Alberti E, Conturba B, Zucca E, Ferrucci F.Exercise-induced pulmonary hemorrhage (EIPH) is a condition affecting up to 95% of racehorses, diagnosed by detecting blood in the trachea after exercise and/or the presence of hemosiderophages in the bronchoalveolar lavage fluid (BALf). Although EIPH is commonly associated with poor performance, scientific evidence is scarce. The athletic capacity of racehorses can be quantified through some parameters obtained during an incremental treadmill test; in particular, the speed at a heart rate of 200 bpm (V200), and the speed (VLa4) and the heart rate (HRLa4) at which the blood lactate concentrati...
Arfuso F, Giannetto C, Giudice E, Fazio F, Piccione G.The effect of exercise on platelet aggregation, albumin and nonesterified fatty acids (NEFAs) values and the correlation among these parameters were evaluated in ten clinically healthy and regularly trained Thoroughbred horses. All horses were subjected to two simulated races. Blood samples were collected by jugular venipuncture before and after the first simulated race (T0PRE and T0POST), every 7 days at rest condition for a month (T1R-T2R-T3R), and before and after the second simulated race (T4PRE and T4POST) in order to assess platelet aggregation, albumin and nonesterified fatty acids (NEF...
Bolwell C, Rogers C, Gee E, McIlwraith W.The objective of the study was to determine the incidence of veterinary events that resulted in a horse failing to finish a race and identify risk factors for musculoskeletal injury (MSI) during a race. Data were obtained on Thoroughbred flat race starts in New Zealand between 1 August 2005 and 31 July 2011 (six racing seasons). Stipendiary Steward's reports were key-word searched to identify veterinary events that prevented a horse from finishing a race. Race data were used calculate the incidence of veterinary events per 1000 horse starts and Poisson regression was used to investigate risk f...
Larsson J, Pilborg PH, Johansen M, Christophersen MT, Holte A, Roepstorff L, Olsen LH, Harrison AP.Few studies have investigated the physiological parameters of endurance horses in Scandinavia. Hence, this two race study has focused on the effects of endurance racing in terms of equine clinicopathological blood parameters, heart score, and fluid use. Race A involved 15 horses (120 km). Two pre- and one post-race blood samples were taken, body condition score was assessed in triplicate pre-race, and an ECG was used to determine heart score. Race B involved 16 horses (65-120 km). One pre- and two post-race blood samples were taken. For both races, horse data as well as fluid intake estima...
Takahashi Y, Takahashi T, Mukai K, Ohmura H.Exercise intensity during races is considerably high. To understand how Thoroughbreds adapt to fatigue conditions, stride parameters for the first and second lap of the race (2400-m, turf) were compared. A high-speed video system was set in a right lateral position about 20 m before the finishing post, with a field view width of about 16 m. The stride frequency, the length between each limb (hind step, diagonal step, fore step, and airborne step), and stride length were measured and analyzed using a generalized linear mixed model. Compared with the first lap, the mean ± standard deviation val...
Velie BD, Hamilton NA, Wade CM.Performance data for 164,046 Thoroughbreds entered in a race or official barrier trial in Australia were provided by Racing Information Services Australia. Analyses estimating the heritability for a range of racing performance traits using a single-trait animal model were performed using ASREML-R. Log of cumulative earnings (LCE; 0.19 ± 0.01), log of earnings per race start (0.23 ± 0.02) and best race distance (0.61 ± 0.03) were all significantly heritable. Fixed effects for sex were significant (P < 0.001) for all performance traits aside from LCE (P = 0.382). With the exception of annual ...
Hernandez JA, Scollay MC, Hawkins DL, Corda JA, Krueger TM.To evaluate horseshoe characteristics and high-speed exercise history as risk factors for catastrophic musculoskeletal injury in Thoroughbred racehorses. Methods: 377 horses (37,529 race starts). Methods: Shoe characteristics included material, toe grab height, heel traction device, pads, and rim shoes. Racing variables were obtained from a computerized database. Forty-three horses that had a musculoskeletal injury and then failed to race or train for 6 months (cases) and 334 noninjured horses from the same race in which a horse was injured (controls) were compared regarding risk factors. Resu...
Nath LC, Elliott AD, Weir J, Curl P, Rosanowski SM, Franklin S.Atrial fibrillation (AF) impacts performance and horse and jockey safety. Understanding the outcomes of AF identified postrace will better inform regulatory policy. Objective: To investigate the outcomes after episodes of AF identified postrace and determine whether affected horses are at increased risk of additional episodes compared to the general racing population. Methods: Total of 4684 Thoroughbred racehorses. Methods: Race records for Thoroughbred horses racing in Hong Kong from 2007 to 2017 were reviewed. Horses that performed below expectation were examined by cardiac auscultation and ...
O'Reilly J, Cheng HL, Poon ET.Weight-making practices have been shown to impair musculoskeletal and physiological function of jockeys. This study investigated the "in-race" heart rate (HR) responses and hydration status during competitive racing, as well as selected physiological and lifestyle parameters of professional jockeys based in Hong Kong. "In-race" HR responses and early morning hydration status of 20 male jockeys were examined in hot and moderate climactic occasions. Additionally, bone mineral density (BMD), dietary intake and lifestyle choices were assessed. Osteopenia was observed in the calcanei of jockeys (le...
Tanner J, Rogers C, Bolwell C, Cogger N, Gee E, Mcllwraith W.The objective was to describe the incidence of failure to finish a race in flat-racing Thoroughbreds in New Zealand as these are summary indicators of falls, injuries and poor performance. Retrospective data on six complete flat racing seasons (n = 188,615 race starts) of all Thoroughbred flat race starts from 1 August 2005 to 31 July 2011 were obtained. The incidence of failure to finish events and binomial exact 95% confidence intervals were calculated per 1000 horse starts. The association between horse-, rider- and race-level variables with the outcomes failure to finish, pulled-up/fell an...