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.
Guan F, Uboh CE, Soma LR, You Y, Liu Y, Li X.Anabolic and androgenic steroids (AASs) are synthetic substances related to the primary male sex hormone, testosterone. AASs can be abused in both human and equine sports and, thus, are banned by the International Olympic Committee and the Association of Racing Commissioners International (ARCI). Enforcement of the ban on the use of AASs in racehorses during competition requires a defensible and robust method of analysis. To address this requirement, a high-throughput ultra high-performance liquid chromatography-mass spectrometric (UHPLC-MS) method was developed for the detection, quantificati...
Pokrywka A, Gorczyca D, Jarek A, Kwiatkowska D.Alfons Bukowski (1858-1921) is commonly regarded as the pioneer of anti-doping research. In 1910, he developed a method to detect alkaloids in horse saliva. One hundred years later, this is a good moment to remember Bukowski, an outstanding Polish pharmacist, often mistakenly represented in world literature as a Russian chemist. It is also an occasion to mention that the real driving forces in the history of doping were events related to horse rivalry.
Revold T, Larsen S, Ihler CF.Less than a third of Norwegian-Swedish Coldblooded Trotters (NSCTs) have started racing as three year olds since the year 2000 despite the fact that large sums are paid out as price-money in the three year season. Recruitment races are arranged by the Norwegian Trotting Association (NTA) to stimulate early training. The management of young horses varies considerably and a large majority is reared by amateurs. The aim of the present study was to identify predictors of early race starts in young NSCT horses under field conditions. Methods: Of the 801 registered NSCT horses born in 2005, 144 were...
Frisbie DD, Mc Ilwraith CW, Arthur RM, Blea J, Baker VA, Billinghurst RC.Biomarkers have shown some in vivo promise for the detection of musculoskeletal injuries, but further study to assess biomarker levels in clinical orthopaedic disease is required. Objective: To assess 7 serum biomarkers for the detection of musculoskeletal injuries. Methods: Two- and 3-year-old racehorses were entered into the study (n = 238). Exit criteria were lack of training for >30 days, or completion of 10 study months. Data from horses with solitary musculoskeletal injuries and completion of >2 months were analysed. Musculoskeletal injury was considered intra-articular fragmentation (IA...
Lyle CH, Uzal FA, McGorum BC, Aida H, Blissitt KJ, Case JT, Charles JT, Gardner I, Horadagoda N, Kusano K, Lam K, Pack JD, Parkin TD, Slocombe RF....To improve the understanding of exercise related sudden death in Thoroughbred racehorses. Objective: To describe the post mortem findings in cases of sudden death associated with exercise in 268 Thoroughbred racehorses. Methods: Gross and histological post mortem findings of 268 cases of sudden death were collated and reviewed. Cases originated from 6 racing jurisdictions around the world. Sudden death was defined as acute collapse and death in a closely observed and previously apparently healthy Thoroughbred racehorse, during, or within one hour after, exercise. Cause of death as determined b...
Gómez MD, Menendez-Buxadera A, Valera M, Molina A.A total of 71 522 records (from 3154 horses) with the times per kilometre (TPK), recorded in Spanish Trotter horses (individual races) from racing performances held from 1991 to 2007, were available for this study. The TPK values for the different age groups (young and adult horses) and different distances (1600-2700 m) were considered as different traits, and a bi character random regression model (RRM) was applied to estimate the (co)variance components throughout the trajectory of age groups and distances. The following effects were considered as fixed: the combination of hippodrome-dat...
Dimaio Knych HK, Steffey EP, Stanley SD.Yohimbine is an alpha 2 adrenergic receptor antagonist, which has been shown to counteract the CNS depressant effects of alpha 2 receptor agonists in a number of species. Recently, our laboratory identified yohimbine in the absence of detectable concentrations of an alpha 2 agonist in a regulatory sample collected from a horse racing in California. This coupled with anecdotal reports of CNS stimulation and documented reports of cardiovascular changes when administered in conjunction with an agonist led us to investigate the pharmacokinetics and pharmacodynamics of yohimbine when administered a...
Orsini JA, Parsons CS, Capewell L, Smith G.This retrospective study investigated the factors associated with a poor outcome (death by euthanasia or from other causes) in horses treated for laminitis at a tertiary care hospital. Cases (n = 247) were defined as patients with laminitis that were euthanized or that died of other causes during hospitalization. Controls (n = 344) were patients with laminitis that survived to be discharged from the hospital. In the final multivariate analysis, the factors significantly associated with an increased risk for death and their respective odds ratios (OR) were as follows: Thoroughbred (OR = 1.57); ...
Cotugna N, Snider OS, Windish J.Athletes involved in horse racing face weight restrictions like wrestlers and dancers; however, the literature is sparse pertaining to nutritional habits of jockeys. The practice of "making weight" causes these athletes to engage in potentially unhealthy practices. A gap in nutritionally sound practices and methods used by jockeys was identified and a desire for nutrition education was expressed to Cooperative Extension of Delaware by representatives of the riders at Delaware Park Race Track. Nutrition assessment was done using the Nutrition Care Process. Twenty jockeys were interviewed using ...
Wright IM, Smith MR.Removal of large chip fractures of the carpal bones and the osteochondral deficits that result, have been associated with a worse prognosis than removal of small fragments in similar locations. Objective: Reducing the articular defects by repair of large osteochondral fragments may have advantages over removal. Methods: Horses with osteochondral chip fractures that were of sufficient size and infrastructure to be repaired with small (2.7 mm diameter) AO/ASIF cortex screws were identified and repair effected by arthroscopically guided internal fixation. Results: Thirty-three horses underwent su...
Kristoffersen M, Hetzel U, Parkin TD, Singer ER.To investigate whether microfractures and alterations in the trabecular bone area are associated with catastrophic bi-axial proximal sesamoid bone fractures (PSBF). Methods: Proximal sesamoid bones (PSB) from 10 racehorses with PSBF and from 10 control racehorses without musculoskeletal injury were examined using the bulk basic fuchsin method. Bone histomorphometric and microfracture analysis was performed, and cases and controls compared using two-sample t-test, paired t-test, and Mann-Whitney U test. Results: There was no significant difference in the microfracture density and the trabecular...
McIlwraith CW.Intra-articular use of corticosteroids has become a recent focus (or re-focus) of attention in the Thoroughbred racing industry. This manuscript reviews the clinical use and scientific basis of intra-articular corticosteroid administration including catastrophic injury, articular cartilage degradation and the development of osteoarthritis (OA), as well as the timing of injection relative to racing.
O'Neill HD, Bladon BM.There is limited information on the treatment of lateral malleolus (LM) fractures in the horse, with no previously published case series for the outcome following arthroscopic removal of such fractures. This report reviews and evaluates findings of a retrospective study of 13 horses admitted to a private equine referral hospital over a 10 year period (1999-2009) that underwent arthroscopic removal of fractures of the LM. Hospital records were reviewed and details including patient history, aetiology of the fracture and limb affected, results of all diagnostic tests and surgical reports were do...
Bailly-Chouriberry L, Noguier F, Manchon L, Piquemal D, Garcia P, Popot MA, Bonnaire Y.Recombinant human erythropoietins (rHuEPOs) are glycoproteins drugs, produced by the pharmaceutical industry to restore production of red blood cells by stimulating human bone marrow for which this pathology has been diagnosed. It is suspected that these molecules are diverted as doping agents in horseracing to enhance oxygen transport and aerobic power in racehorses. Although indirect double-blotting or direct liquid chromatography-mass spectrometry (LC-MS) methods have been developed to confirm the presence of rHuEPO in a sample, the short detection time (48 h) is still a problem for doping ...
Gutierrez J, Eisenberg RL, Koval NJ, Armstrong ER, Tharappel J, Hughes CG, Tobin T.Pemoline is a central nervous system stimulant that has been used to treat attention-deficit hyperactivity disorder and narcolepsy in humans; its identification in horses could be considered evidence of attempts to influence performance. Two recent pemoline 'positives' in English racehorses led us to review the chemical relationships between tetramisole, levamisole, aminorex and pemoline. Pemoline is a simple oxidation product of aminorex, which has been shown in the United States and elsewhere to be an equine metabolite of levamisole. Based on the clear structural relationships between aminor...
Evans DL, Kiddell L, Smith CL.Inflammatory airway disease (IAD) is common in racehorses, and is a cause of wastage in the industry. IAD has been diagnosed by measurement of percent neutrophils (N%) in tracheal aspirates (TA). The aim of this study was to investigate whether spirometric indices of pulmonary function were correlated with N% in TAs. Limits to breathing were measured by analyses of relationships between relative times and relative respiratory gas flows during inspiration and expiration in individual breaths recorded after exercise. Horses with higher N% had significantly lower relative gas flows at the same re...
Forero Rueda MA, Cui L, Gilchrist MD.Jockey head injuries, especially concussions, are common in horse racing. Current helmets do help to reduce the severity and incidences of head injury, but the high concussion incidence rates suggest that there may be scope to improve the performance of equestrian helmets. Finite element simulations in ABAQUS/Explicit were used to model a realistic helmet model during standard helmeted rigid headform impacts and helmeted head model University College Dublin Brain Trauma Model (UCDBTM) impacts. Current helmet standards for impact determine helmet performance based solely on linear acceleration....
Kristoffersen M, Parkin TD, Singer ER.Catastrophic biaxial proximal sesamoid bone fractures (PSBF) have not yet been described in detail in the UK racing population. Objective: To determine the incidence and relative risk (RR) of PSBF in different types of racing in the UK; and to describe horse-level characteristics and racing histories of horses sustaining these injuries. Methods: Distal limbs were collected from all racehorses suffering catastrophic fractures during racing at all 59 racecourses in the UK, in a prospective study from February 1999 to December 2004. Post mortem investigation identified the anatomical location and...
Kamm JL, Bramlage LR, Schnabel LV, Ruggles AJ, Embertson RM, Hopper SA.Analysis was performed to examine a method for refining the preoperative prognosis for horses that had surgery to remove apical fractures of the proximal sesamoid bones (PSBs). Objective: To determine if: 1) there was a difference in size or configuration of apical fractures between the different anatomical locations of the PSBs, which have been shown to affect the prognosis; and 2) the size or configuration could predict the prognosis for racehorses with these fractures. Methods: The study included 110 weanlings and yearlings and 56 training racehorses that underwent surgery to remove apical ...
Isgren CM, Upjohn MM, Fernandez-Fuente M, Massey C, Pollott G, Verheyen KL, Piercy RJ.Exertional rhabdomyolysis syndrome is recognised in many athletic horse breeds and in recent years specific forms of the syndrome have been identified. However, although Standardbred horses are used worldwide for racing, there is a paucity of information about the epidemiological and performance-related aspects of the syndrome in this breed. The objectives of this study therefore were to determine the incidence, risk factors and performance effects of exertional rhabdomyolysis syndrome in Standardbred trotters and to compare the epidemiology and genetics of the syndrome with that in other bree...
Nicholson AM, Trumble TN, Merritt KA, Brown MP.To determine the effects of horse age, osteochondral injury, and joint type on a synthesis biomarker and 3 degradative biomarkers of type II collagen in Thoroughbreds. Methods: Healthy rested adult (3- to 12-year-old) Thoroughbreds (n = 19), yearling (1- to 2-year-old) Thoroughbreds (40), and Thoroughbred racehorses (2 to 7 years old) undergoing arthroscopic surgery for removal of osteochondral fragments that resulted from training or racing (41). Methods: Samples of blood and metacarpophalangeal, metatarsophalangeal, or carpal joint synovial fluid (SF) were collected from all horses. Commerci...
Anthenill LA, Gardner IA, Pool RR, Garcia TC, Stover SM.To compare macrostructural and microstructural features of proximal sesamoid bones (PSBs) from horses with and without PSB midbody fracture to gain insight into the pathogenesis of PSB fracture. Methods: PSBs from 16 Thoroughbred racehorses (8 with and 8 without a PSB midbody fracture). Methods: Parasagittal sections of fractured and contralateral intact PSBs from horses with a PSB fracture and an intact PSB from age- and sex-matched control horses without a PSB fracture were evaluated for visual, radiographic, microradiographic, histologic, and his-tomorphometric differences in bone porosity,...
Abraham G, Allersmeier M, Schusser GF, Ungemach FR.The aim of this study was to determine if topical application of dexamethasone affected the serum concentrations of thyroid hormones (triiodothyronine T(3) and thyroxine T(4)), glucose, triglycerides, total protein and insulin in normal horses. Ten horses were treated twice daily for 10 days with 50 g dexamethasone using an ointment formulation. Thyroid hormones and insulin were assayed using standard radioimmunoassay methods, while glucose, triglycerides and total protein were determined using a standard enzymatic method and the Biuret reaction, respectively. An increase in serum glucose and ...
Knych HK, McKemie DS, Stanley SD.The use of performance-enhancing drugs in the horse racing industry combined with the need for more rational approaches in the use of therapeutic agents in equids necessitates additional studies on the spectrum, content, and catalytic activities of hepatic cytochrome P450 monooxygenases in this species. In this study, three cytochrome P450 (P450) monooxygenases in the 3A family were cloned from, sequenced, and expressed in a baculovirus expression system. The proteins were designated CYP3A89, CYP3A96, and CYP3A97. Expression studies produced various results among the three proteins. CYP3A89 ap...
Jalim SL, McIlwraith CW, Goodman NL, Anderson GA.The effectiveness and best method to manage dorsal cortical stress fractures is not clear. This study was performed to evaluate the success of lag screw fixation of such fractures in a population of Thoroughbred racehorses. Objective: Lag screw fixation of dorsal cortical stress fractures is an effective surgical procedure allowing racehorses to return to their preoperative level of performance. Methods: The records of 116 racehorses (103 Thoroughbreds) admitted to Equine Medical Centre, California between 1986 and 2008 were assessed. Information obtained from medical records included subject ...
Physick-Sheard PW, McGurrin MK.A lack of information on normal heart rhythm at maximal effort hampers investigation of poor performance and sudden death in Standardbred racing. Objective: To characterize rhythm variations during scheduled racing in clinically normal Standardbred horses. Methods: Two hundred and eighty-eight Standardbred horses competing in 40 scheduled races at a Southern Ontario racetrack. Methods: Observational study, convenience sampling: Heart rhythm was monitored by ECG from harnessing to postrace recovery and assessed visually and by examining heart rate intervals. Rhythm variations were used as respo...
McGivney BA, McGettigan PA, Browne JA, Evans AC, Fonseca RG, Loftus BJ, Lohan A, MacHugh DE, Murphy BA, Katz LM, Hill EW.Digital gene expression profiling was used to characterize the assembly of genes expressed in equine skeletal muscle and to identify the subset of genes that were differentially expressed following a ten-month period of exercise training. The study cohort comprised seven Thoroughbred racehorses from a single training yard. Skeletal muscle biopsies were collected at rest from the gluteus medius at two time points: T(1) - untrained, (9 +/- 0.5 months old) and T(2) - trained (20 +/- 0.7 months old). Results: The most abundant mRNA transcripts in the muscle transcriptome were those involved in mus...
Hitchens PL, Blizzard CL, Jones G, Day L, Fell J.Riding thoroughbred racehorses is a hazardous occupation. In this study, we investigated risk factors associated with falls by licensed thoroughbred racing jockeys participating in flat races conducted in Australia. Methods: Data on race-day falls were extracted from stewards' reports. Denominator data were provided by Racing Information Services Australia on races conducted in Australia from August 2002 until July 2006. Incidence rate ratios (IRRs) were estimated using Poisson regression. Analyses were stratified by race grade (maiden, class, open/restricted). Results: In multivariable analys...
Peterson ML, Reiser RF, Kuo PH, Radford DW, McIlwraith CW.Differences in racing times have been noted on synthetic track surfaces that appear to depend on the temperature of the track. No published study to date has considered this effect in a systematic manner. Objective: To investigate the relationship between temperature of track and speed of horses racing on a synthetic surface. Potential changes in the wax component of the synthetic track were investigated as one possible cause of changes in the track speed at the temperatures observed. Methods: At Del Mar racetrack (California, USA), the air, surface and subsurface temperatures at 4 depths in t...
O'Meara B, Bladon B, Parkin TD, Fraser B, Lischer CJ.There is limited information regarding the number of races and the period for evaluation of outcome which is critical for assessment of SDF tendonitis treatments. Objective: To evaluate the re-injury rate and racing performance of Thoroughbred racehorses that sustain SDF tendonitis in relation to matched controls in terms of number of races post treatment and maximum racing performance ratings before and after injury. Methods: Clinical records and racing histories of 401 racehorses with a first occurrence of SDF tendonitis diagnosed by ultrasonography. Controls were of the same age, sex and we...
Ishii H, Shibuya M, Leung GN, Nozawa S, Yamashita S, Yamada M, Kushiro A, Kasashima Y, Okada J, Kawasaki K, Kijima-Suda I.GW1516 is a peroxisome proliferator-activated receptor-δ (PPAR-δ) agonist that is banned in horseracing and equestrian sports. Long-term detection and longitudinal distribution of GW1516 in the mane of a horse are reported for the first time and this hair analysis could prolong the detection window of GW1516 for doping control. Methods: Mane hairs were divided into three segments (0-7, 7-15, and >15 cm from the cut end) and completely pulverized and homogenized for analysis. The pulverized hair samples were extracted with methanol followed by further purification and the extracts were a...
Velie BD, Jäderkvist Fegraeus K, Ihler CF, Lindgren G, Strand E.Studies of large racing populations have established clear differences in the career profile of stallions, mares and geldings. Multiple studies have also demonstrated positive effects on racing careers for horses that commence racing at a younger age. However, the applicability of these studies to small, native racing populations is unknown and warrants investigation. Objective: To provide summary statistics for performance outcomes for the Norwegian-Swedish Coldblooded Trotter and to document and provide evidence on the current differences in racing careers across age at first start groups, s...
Haussler KK, Stover SM.Thirty-six Thoroughbred racehorses that died at California racetracks between October 1993 and July 1994 were evaluated for stress fractures in the caudal portion of the thoracic and lumbosacral regions of the spine and the pelvis. The lumbosacral spine and pelvis were collected, debrided of soft tissues and examined visually for the presence of an incomplete fracture line and focal periosteal proliferation, characteristic of a stress fracture. Sixty-one per cent of specimens had evidence of stress fracture in the caudal portion of the thoracic and lumbosacral regions of the spine and the pelv...
Physick-Sheard P, Avison A, Sears W.Ontario's Alcohol and Gaming Commission records equine racing fatalities through its Equine Health Program. The present study examined all Thoroughbred fatalities from 2003 to 2015, inclusive, to identify associations. Official records and details of fatalities were combined in multivariable logistic regression modelling of 236,386 race work-events (433 fatalities), and 459,013 workout work-events (252 fatalities). Fatality rates were 2.94/1000 race starts (all fatalities) and 1.96/1000 (breakdowns only) with an overall rate of 2.61% or 26.1 fatalities/1000 horses. Comparison with published re...
Von Wittke P, Lindner A, Deegen E, Sommer H.In this study the effects of training history on the results of a standardized two-speed test in competing Thoroughbreds were investigated during a racing season. For nine Thoroughbreds, 1,755 training days were recorded. Within the observation period each horse completed a two-speed field test at intervals of 6-8 wk to determine its running velocity (v) eliciting blood lactate concentrations of 4 (v4) and 12 mmol/l (v12). Horses performed 29 two-speed tests. Changes of v4 and v12 in a horse between two consecutive tests were used to assess effects of training history variables calculated for ...
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 (...
Stefaniuk-Szmukier M, Ropka-Molik K, Piórkowska K, Bugno-Poniewierska M.One of the most significant reason of economic loss on race track performance is lame in performed horses. Primarily, due to the failure within proper bone maintenance during conditioning in young horses. The training overload causes bone turnover disturbances in homeostasis between bone resorption and bone formation which promote the bone loss. Within our study we investigated training induced changes in transcript abundance of genes (NFATc1, CTSK, DAP12, CLEC5A, IL6ST, VAV3) involved in osteoclastogenesis hence bone resorption, in whole blood of Arabian horses. The expression pattern of all ...
Kamerling S, Wood T, DeQuick D, Weckman TJ, Tai C, Blake JW, Tobin T.Narcotic analgesics produce pharmacological effects by interacting with specific opiate receptors. At least five major types of opiate receptors have been recognised. These include mu (morphine) and kappa (ethylketazocine) receptor types. Narcotic analgesics which interact with mu receptors produce locomotor and autonomic stimulation at doses that produce little or no analgesia. Therefore, use of these drugs as analgesics in equine medicine has not been very satisfactory. Theoretical considerations suggested that the role of kappa agonists in equine analgesia be investigated. Using a pure kapp...
Walker WT, Kawcak CE, Hill AE.To characterize medial femoral condyle (MFC) morphometrics and subchondral bone density patterns in Thoroughbred racehorses and to determine whether these variables differ between left and right limbs. Methods: Stifle joints harvested from 6 Thoroughbred racehorses euthanized for reasons other than hind limb lameness. Methods: The distal portion of the left and right femurs of each cadaver was scanned via CT. Hounsfield units were converted to dipotassium phosphate equivalent densities through use of a phantom on each specimen. Medial femoral condyle width, length, height, and curvature; subch...
Woodie JB, Ruggles AJ, Bertone AL, Hardy J, Schneider RK.To determine whether fracture fragment dimensions, suspensory ligament damage, and racing status at the time of injury were associated with outcome in Standardbred horses with apical fracture of the proximal sesamoid bone. Methods: Retrospective study. Methods: 43 Standardbred racehorses. Methods: Medical records, racing records, and radiographs were reviewed, and ultrasonographic findings were scored. Measurements of the fractured portion of the proximal sesamoid bone were made. Results: Seventy-four percent (32/43) of horses were pacers, and 26% (11/43) were trotters. Statistical differences...
Trumble TN, Scarbrough AB, Brown MP.To investigate the effects of exercise and osteochondral (OC) injury on type II collagen degradation products (collagenase cleavage neoepitope commercially known as C2C) in synovial fluid (SF) from Thoroughbred (TB) racehorses and to compare these results with radiographic and arthroscopic scores of severity of joint injury. Methods: Metacarpophalangeal/metatarsophalangeal (MCP/MTP) and carpal SF was obtained from (1) 20 normal rested horses, (2) the same horses after 5 to 6 months of race training, and (3) 27 horses with OC injury from racing. For group 3, radiographic and arthroscopic scores...
Peter VG, O'Keeffe TA, Smith LCR, Schweizer-Gorgas D. To investigate the racing performance of Thoroughbred horses with osseous cyst-like lesions (OCLLs) in the distal phalanx causing lameness and treated conservatively. To assess horses' ability to race and perform after radiographic identification of OCLL in the distal phalanx of Thoroughbred horses with lameness at the time of detection and undergoing conservative treatment. Retrospective case control study. The clinical database of one equine clinic was reviewed in a 10-year period for Thoroughbreds showing lameness localized to the foot and a radiographic diagnosis of OCLL in the distal ...
Schrurs C, Dubois G, Van Erck-Westergren E, Gardner DS.The racing industry is supported by a predominance of female stablehands and work riders, but few become professional jockeys. Female jockeys have recently had notable race success. No study has assessed whether the sex of the rider may subtly influence racehorse physiology to affect performance. Here, using a validated exercise tracking system (the 'Equimetre'™) that records many physiological parameters simultaneously, this study characterised racehorse cardiovascular (heart rate, heart rate recovery) and biomechanical (stride length and frequency) parameters at various exercise intensitie...
Hitchens PL, Curry B, Blizzard CL, Palmer AJ.The profession of a horse-racing jockey is a dangerous one. We developed a decision tree model quantifying the effects of implementing different safety strategies on jockey fall and injury rates and their associated costs. Methods: Data on race-day falls were obtained from stewards' reports from August 2002 to July 2009. Insurance claim data were provided by Principal Racing Authorities and workers' compensation authorities in each jurisdiction. Fall and claim incidence data were used as baseline rates. The model considered (1) the status quo, in which policy was unchanged; and (2) compared it...
Knych HK, Harrison LM, Casbeer HC, McKemie DS.Methylprednisolone acetate (MPA) is commonly administered to performance horses, and therefore, establishing appropriate withdrawal times prior to performance is critical. The objectives of this study were to describe the plasma pharmacokinetics of MPA and time-related urine and synovial fluid concentrations following intra-articular administration to sixteen racing fit adult Thoroughbred horses. Horses received a single intra-articular administration of MPA (100 mg). Blood, urine, and synovial fluid samples were collected prior to and at various times up to 77 days postdrug administration a...
Carmalt JL, Borg H, Näslund H, Waldner C.The aim of this study was to determine whether horses with a proximal palmar/plantar first phalangeal osteochondral fragment (POF) had comparable racing careers (prior to and following surgery) to horses without this fracture. A retrospective cohort study included 174 Swedish Standardbred trotters with osteochondral fragmentation in the palmar/plantar fetlock joint and 613 radiographically negative control horses presented for prepurchase examinations. Medical records and radiographs were examined for each horse. Racing data were retrieved from online Swedish Standardbred harness racing record...
Pearce DJ, Hitchens PL, Malekipour F, Ayodele B, Lee PVS, Whitton RC.Fatigue-induced subchondral bone (SCB) injury is common in racehorses. Understanding how subchondral microstructure and microdamage influence mechanical properties is important for developing injury prevention strategies. Mechanical properties of the disto-palmar third metacarpal condyle (MCIII) correlate poorly with microstructure, and it is unknown whether the properties of other sites within the metacarpophalangeal (fetlock) joint are similarly complex. We aimed to investigate the mechanical and structural properties of equine SCB from specimens with minimal evidence of macroscopic disease....
Tou K, Cawley A, Bowen C, Sornalingam K, Fu S.The conventional detection of exogenous drugs in equine doping samples has been used for confirmation and subsequent prosecution of participants responsible. In recent years, alternative methods using indirect detection have been investigated due to the expanding number of pharmaceutical agents available with the potential of misuse. The monitoring of endogenous biomarkers such as hydrocortisone (HC) has been studied in equine urine with an international threshold of 1 μg/ml established; however, there is no current threshold for equine plasma. The aim of this research was to investigate pl...
Ainsworth DM, Erb HN, Eicker SW, Yeagar AE, Viel L, Sweeney CR, Lavoie JP.To determine whether results of physical or radiographic examination or biochemical analyses in adult racehorses with primary lung abscesses were associated with ability to race following treatment. Methods: Multiple-center retrospective study. Methods: 25 Standardbreds and 20 Thoroughbreds. Methods: Medical records of horses with a primary lung abscess that were admitted to any of 4 veterinary teaching hospitals were reviewed. Results of physical examination, laboratory testing, and thoracic radiography were reviewed. Racing performance after treatment was compared with performance before ill...
Perkins NR, Reid SW, Morris RS.To describe characteristics of Thoroughbred training stables in Matamata and in all other locations in New Zealand combined, over two 19-month time periods in 1996-1997 and 1998-1999, representing equal length periods immediately prior to and after the construction of a new training surface at the Matamata Racing Club. Methods: Retrospective records covering all horses training and racing in New Zealand during two 19-month time periods (1996-1997 and 1998-1999), covering 161 locations, were obtained from New Zealand Thoroughbred Racing (NZTR). Outcome variables included whether a horse was rac...
Kuroda T, Minamijima Y, Nomura M, Yamashita S, Yamada M, Nagata S, Mita H, Tamura N, Fukuda K, Kuwano A, Kusano K, Toutain PL, Sato F.For medication control in several jurisdictions, withdrawal time is the period of refrain from racing after drug administration. It is set by adding a safety period to an experimental detection time. However, there are no reports of statistical analyses of detection time for the determination of withdrawal time in flunixin meglumine-treated horses. Objective: To analyse the population pharmacokinetics of flunixin in horses through the generation of a dataset for detection time statistical analysis and predictions via Monte Carlo simulation. Methods: Experimental study. Methods: Drug plasma and...
O'Callaghan MW, Pascoe JR, Tyler WS, Mason DK.Detailed physical and clinical examinations were performed on 26 Thoroughbred racehorses which were used subsequently in a series of studies to investigate the contribution of the pulmonary and bronchial arterial circulations to the pathophysiology of exercise-induced pulmonary haemorrhage (EIPH). Twenty-five of the horses had been retired from race training in Hong Kong during the 1984-85 season, all but four raced that season; one horse had been retired the previous season. The average number of races for the group that season was 4.1 +/- 2 with an average distance of 1502 +/- 216 metres, me...
Rossi TM, Kavsak PA, Maxie MG, Pearl DL, Pyle WG, Physick-Sheard PW.Accumulating evidence indicates intense exercise can be associated with myocardial damage. Investigating the impact of maximal effort on myocardium and exploring possible association of injury with rhythm disturbance requires a high-sensitivity cardiac troponin assay. The objectives of this study were: (1) to determine the effect of racing on serum cardiac troponin I (cTnI) in Standardbred horses using a high-sensitivity assay; (2) to determine the 99th percentile of cTnI in healthy horses and investigate the effect of demographic variables on cTnI prevailing pre-race in Standardbred horses us...
Doucet MY, Viel L.A clinical study was performed to determine whether clinical, endoscopic, radiographic, bronchoalveolar lavage (BAL) cytological, and pulmonary biopsy findings could be correlated in horses with exercise-induced pulmonary hemorrhage (EIPH) compared with controls. Racing standardbred horses were selected as either EIPH (n = 10) or control (n = 10), based on repeated postexertional endoscopy of the lower airways. Complete physical and respiratory examinations were performed and blood samples were submitted for arterial blood gas analysis, hematologic study, and fibrinogen determination. Bilatera...
Henderson CE, Sullins KE, Brown JA.To determine long-term effects of transendoscopic, laser-assisted ventriculocordectomy (LAVC) on airway noise and performance in horses with naturally occurring left laryngeal hemiplegia. Methods: Retrospective case series. Methods: 22 horses with left laryngeal hemiplegia treated by means of LAVC. Methods: Medical records were reviewed and initial complaint, intended use of the horse, duration of abnormal airway noise, preoperative performance level, endoscopic findings, surgical procedure, postoperative treatment, and complications were recorded. Follow-up telephone interviews with owners an...
Kuuranne T, Thomas A, Leinonen A, Delahaut P, Bosseloir A, Schänzer W, Thevis M.Insulin is a peptide hormone consisting of two peptide chains (A- and B-chain) that are cross-linked by two disulfide bonds. To obtain improved pharmacokinetic onset of action profiles of insulin treatment in diabetic patients, recombinant long-, intermediate-, and rapid-acting insulin analogs are produced, in which the C-terminal end of the B-chain plays an especially important role.A review of the veterinary literature reveals the low prevalence of equine type I diabetes mellitus, which indicates that the therapeutic use of insulin in racing horses is unlikely. Although there is no unequivoc...
Brownstein AL, Read SJ, Simon D.These studies were designed to test cognitive dissonance theory's assertion that alternatives are not reevaluated before a choice. Participants viewed information about horses in a simulated race and rated each one's chance of winning three times before placing their bet and once after placing it. It was found that ratings of the chosen horse increased within the predecision period as well as after betting. Predecision bolstering occurred even when participants did not expect to bet, and predecision preference increased with task importance and participant expertise. The findings are attribute...
Yamada M, Kinoshita K, Kurosawa M, Saito K, Nakazawa H.Nandrolone (17beta-hydroxy-4-estren-3-one, NAD) is an endogenous steroid hormone; thus, the detection of its metabolites is not conclusive of NAD doping in racehorses. NAD doping control in male horses is based on the threshold, namely, the concentration ratio of 5alpha-estran-3beta,17alpha-diol (ETA) to 5(10)-estren-3beta,17alpha-diol (ETE). The ETA/ETE ratio of 1/1 was determined based on statistical data of authentic horses in International Federation of Horseracing Authorities. To individuals with complex metabolic disorders, however, such a threshold might not be applicable. The aim of th...
Bowers J, Slocombe R.To determine commonly used girth tensions in Thoroughbred racehorses in the Melbourne metropolitan area. Methods: A prospective industry survey. Methods: Strappers were instructed to tension girths, using the same saddle, under-saddle packing and girth, sufficiently to hold the saddle for racing. These tensions were continuously recorded by an in-line load cell in the girth. Seventeen strappers from five stables participated in the study, which was conducted on 91 horses. Results: Resting girth tensions varied considerably. The mean tension on inhalation was 13 +/- 0.4 kg. Male strappers recor...
Hellings IR, Skjerve E, Karlstam E, Valheim M, Ihler CF, Fintl C.There are no reports on the number of fatalities or causes of death in the Norwegian and Swedish harness racehorses. Objective: The incidence rates (IRs), risk factors, and postmortem findings in horses that died or were euthanized associated with racing between 2014 and 2019 were investigated. Methods: Thirty-eight Standardbreds and 10 Norwegian-Swedish Coldblooded Trotters died or were euthanized associated with racing. A total of 816 085 race-starts were recorded. Methods: Incidence rates were calculated for both countries and horse breeds. Risk factors for sudden death were identified us...
