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.
Weiss DJ, McClay CB, Smith CM, Rao GH, White JG.Platelet function was evaluated in horses with exercise-induced pulmonary hemorrhage (bleeder) and in control horses (nonbleeder). Platelet aggregation, secretion, and adhesion to rabbit aortic subendothelium were similar for bleeders and nonbleeders. Platelets readily aggregated in response to ADP, thrombin, collagen, and arachidonic acid, but platelet secretion occurred only with high concentrations of thrombin. Platelets readily adhered to rabbit aortic subendothelium and tended to form large thrombi rather than platelet monolayers or aggregates. These data suggest that horses may be predis...
Ross MW, Richardson DW, Beroza GA.Thirteen Standardbreds had subchondral lucency of the third carpal bone (C3), described as single or multiple central areas of C3 bone loss in the radial fossa. Sclerosis of the radial fossa was also detected. The mean age of 9 stallions, 3 mares, and 1 gelding was 4.1 years (range, 3 to 7 years). All horses had an acute moderate to severe lameness referable to the middle carpal joint. A dorsoproximal dorsodistal (skyline) radiographic projection was most useful and identified mild (3 horses), moderate (6 horses), and severe (4 horses) subchondral lucency and sclerosis of the radial fossa. The...
Stick JA, Derksen FJ.Videoendoscopy of the larynx during treadmill exercise was used to determine the surgical treatment of upper airway obstruction in a Standardbred colt. Surgical correction of right-sided laryngeal hemiplegia, first by laryngoplasty, then subtotal arytenoidectomy, was ineffective. Videoendoscopy indicated, and upper airway flow mechanics confirmed, that the laryngeal opening was adequate at rest, but obstruction occurred during exercise. On the basis of the appearance of the larynx during high airflow rates on slow-motion playback of the videorecording, total arytenoidectomy was performed, whic...
Imaizumi K, Nakamura T, Kiryu K, Kanemaru T, Kaneko M.The aorta and extrapulmonary artery were examined pathologically in 33 thoroughbred racehorses ranging in age from 1 to 5 years. Many of the great vessels of these horses exhibited degenerative or sclerotic changes in the media with neither lipidosis nor deposits of cholesterol. The severe lesions were predominantly observed at the bifurcation of the pulmonary artery. The severity of the lesions in both the aorta and pulmonary artery appeared to be associated with the racing career of the racehorse rather than with increasing age. Histopathogenetically, the medial changes in the great vessels ...
Guthrie AJ, Nichas E, Viljoen FV, Hartmann AM, Killeen VM.A case of sustained supraventricular tachycardia of unknown aetiology in a two-year-old Thoroughbred filly is reported. The cardiac dysrhythm was successfully treated by the oral administration of quinidine sulphate. Conversion of the dysrhythm to sinus rhythm occurred approximately 80 min after the initial dose of 5 g of quinidine sulphate. The horse returned to training approximately 2 months after treatment and has since successfully returned to racing.
Wood T, Tai CL, Taylor DG, Woods WE, Wang CJ, Houtz PK, Tai HH, Weckman TJ, Yang JM, Sturma L.Detomidine is a potent non-narcotic sedative agent which is currently in the process of being approved for veterinary clinical use in the United States. Since no effective screening method in horses is available for detomidine, we have developed an 125I radioimmunoassay for detomidine in equine blood and urine as part of a panel of tests for illegal drugs in performance horses. Our 125I radioimmunoassay has an I-50 for detomidine of approximately 2 ng/ml. Our assay shows limited cross-reactivity with the pharmacodynamically similar xylazine, but does not cross-react with acepromazine, epinephr...
Collins EA.Four cases of equine lameness were treated with intra-articular polysulphated glycosaminoglycan. Two, two-year-old flat racers were treated conservatively after traumatic injury. They subsequently became lame owing to the formation of new bone and osteophytes. Two older steeplechasers were lame owing to degenerative joint disease. The four horses were treated with intra-articular injections of polysulphated glycosaminoglycans and, after three or four injections, they became clinically sound and were able to continue racing with varying degrees of success.
Nunamaker DM, Butterweck DM, Provost MT.Geometric properties of the third metacarpal bone were compared between the young and adult Standardbred and Thoroughbred racehorse. The change in shape during growth and superimposed training was dramatic in both breeds but the Thoroughbred showed the greatest difference in the minimum moment of inertia as the animal matured. Males had larger moments of inertia throughout the length of the diaphysis than did females. The differences in geometric properties of the third metacarpal bone between the Thoroughbred and Standardbred were related to the incidence of fatigue fractures which are common...
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...
Reef VB, Lalezari K, De Boo J, van der Belt AJ, Spencer PA, Dik KJ.Pulsed-wave Doppler echocardiography was performed on 30 clinically normal 1- to 6-year-old racing Standardbreds. There were 13 females, 13 geldings, and 4 stallions. Cardiac disease was not detected with M-mode, 2-dimensional real-time or pulsed-wave Doppler echocardiography. Normal flow velocities for right and left atrial outflow, right and left ventricular outflow, the aorta, and pulmonary artery were determined. Peak flow velocities for right and left atrial outflow occurred during the rapid filling phase and were higher toward the mitral valve (mean, 0.70 +/- 0.24 m/s) than toward the tr...
Tobin T, Kwiatkowski S, Watt DS, Tai HH, Tai CL, Woods WE, Goodman JP, Taylor DG, Weckman TJ, Yang JM.We have developed and evaluated a one step enzyme-linked immunosorbent assay (ELISA) test for sufentanil and a 125I radioimmunoassay test for alfentanil as part of a panel of pre- and post-race tests for narcotic analgesics in racing horses. Our sufentanil ELISA test detects sufentanil with an I-50 of about 0.5 ng/ml. The test is rapid and economical in that it can be read with an inexpensive spectrophotometer, or even by eye. The test readily detects the presence of sufentanil or its metabolites in equine blood and urine from 1 to 24 hours respectively after administration of therapeutic or s...
Tobin T, Watt DS, Kwiatkowski S, Tai HH, Blake JW, McDonald J, Prange CA, Wie S.We have introduced large scale non-isotopic immunoassay testing into pre- and post-race drug testing in racehorses. The technologies utilized are Particle Concentration Fluorescence Immuno Assay (PCFIA) and the one-step Enzyme Linked Immuno Sorbent Assay (ELISA). These technologies are rapid, inexpensive, and highly effective. On introduction into post-race testing in the Western United States, these ELISA tests exposed several previously undetected patterns of drug abuse. The drugs detected were buprenorphine, oxymorphone, mazindol, sufentanil and cocaine. This led to the suspension of a larg...
Sweeney CR, Hall J, Fisher JR, Leary HJ, Soma LR, Spencer PA.The efficacy of water vapor-saturated air as a treatment for horses with exercise-induced pulmonary hemorrhage (EIPH) was studied. Horses selected for study (n = 14) had grade 1 or greater hemorrhage in the trachea after a minimum of 4 breezes between 0.8 and 1 km, as determined by endoscopy. Nine horses were treated with water vapor-saturated air; 5 horses were not treated. When the mean and maximal EIPH scores from the pretreatment period were compared with the mean and maximal EIPH scores from the treatment period in both treated and nontreated groups, there was no significant difference be...
Wilson BD, Neal RJ, Howard A, Groenendyk S.Standardbred pacers have been studied under race conditions to describe the gait of the pacer, and to determine relationships between stage of the race, finish order and selected gait kinematics. Overlap increased with the stage of the race while pacing speed decreased marginally for low order pacers and increased for high order finishers. High order finishing pacers appear to have greater stance and stride lengths than do low order finishers. Pacers could be separated into low order and high order groups on the basis of their movement patterns. High order pacers exhibited greater ranges of li...
Honnas CM, Wheat JD.Transnasal, axial division of the aryepiglottic fold was performed to correct entrapment of the epiglottis in 20 sedated, standing horses, using a hooked bistoury and topical anesthesia. Presenting complaints included decreased exercise tolerance or loss of racing performance, abnormal respiratory noise, and coughing. The surgical procedure was technically easy to perform with a minimum of instrumentation. The horses were rested an average of 18 days before race training or riding was resumed. Evaluation of racing records or contact with owners indicated that most affected horses competed succ...
Boero MJ, Kneller SK, Baker GJ, Metcalf MR, Twardock AR.Injury of the lateral collateral ligaments of the tarsocrural joints was diagnosed in nine Standardbred pacers. The average age was 4.9 years. The severity of the lameness varied from severe to subtle and joint effusion was seen in eight of 10 tarsocrural joints. A positive hindlimb flexion test was seen in four of six cases in which results were recorded. The identification of the site of involvement was based on a focal intense 'hot spot' seen on scintigraphy, and new bone formation seen radiographically at the anatomical sites of insertion of the long lateral collateral ligament of the tars...
Kwiatkowski S, Sturma L, Dai MR, Tai HH, Watt DS, Tai CL, Woods WE, Weckman TJ, Yang JM, Wood T.We have developed and evaluated a one step enzyme-linked immunosorbent assay (ELISA) test and a particle concentration fluorescence immunoassay (PCFIA) test for acepromazine as part of a panel of pre- and post-race tests for illegal medications in racing horses. These tests are rapid, sensitive and economical and development of the tests occurred in less than seven months. The ELISA test detects acepromazine with an I-50 of about 150 pg/ml. In vivo, it readily detects the presence of acepromazine or its metabolites in equine blood and urine from 8 to 72 hours or longer, respectively, after adm...
Stephens PR, Richardson DW, Spencer PA.Case records and radiographs of 155 horses with third carpal bone (C3) slab fractures were reviewed. Of these cases, race records were obtained for 72 Thoroughbreds and 61 Standardbreds. Three performance criteria were examined: ability to make 1 start, ability to make 10 starts or earn $2,000 (within 1 year of first start after the fracture), and earnings per start. Treatment distribution (lag screw fixation, fragment excision, or rest) was similar in both breeds. Significant differences between breeds were identified in age and sex distributions, fracture displacement, and postinjury perform...
Valberg S, Essén Gustavsson B, Skoglund Wallberg H.The oxidative capacity of skeletal muscle fibre types was evaluated histochemically using the nicotinamide dinucleotide diaphorase (NADH-D) staining, and biochemically by measuring the activity of citrate synthase (CS) in both whole muscle samples and in pools of fibres of identified type. Duplicate determinations of the NADH-D staining pattern resulted in standard deviations (sd) between duplicates of 6 and 11 per cent for two observers. The NADH-D pattern was found to differ between observers. Duplicate determinations of CS activity in the same fibre pools resulted in an sd value of 2.9 mumo...
Gunson DE, Sweeney CR, Soma LR.Pathologic changes are described in 11 horses that died during racing or training; 9 died of acute pulmonary hemorrhage (exercise-induced pulmonary hemorrhage), 1 died of exsanguination, and 1 died of CNS trauma. Cardiac lesions were not found in any horse. Severe engorgement of pulmonary vessels, with hemorrhage into alveoli, airways, interstitium, and subpleural tissues, was observed in all 9 horses that died of exercise-induced pulmonary hemorrhage. Infiltration of eosinophils and/or lymphocytes around vessels and airways was seen in 6 horses. Focally extensive fibrosis was observed in the ...
Woods WE, Wang CJ, Houtz PK, Tai HH, Wood T, Weckman TJ, Yang JM, Chang SL, Blake JW, Tobin T.A one step enzyme-linked immunosorbent assay (ELISA) and a particle concentration fluorescent immunoassay (PCFIA) test for furosemide were evaluated as part of a panel of pre- and post-race tests for illegal medication of racing horses. These tests are very sensitive to furosemide with an I-50 for furosemide of about 20 ng/ml. The test is also rapid; an average pre-race complement of 10 samples can be analyzed in 90 minutes or less. The ELISA test results can be read with an inexpensive spectrophotometer, or even by eye. Both the PCFIA test and the ELISA test readily detect the presence of fur...
Martin GS, Haynes PF, McClure JR.Between 1977 and 1984, 31 Thoroughbred horses (mean age, 2.8 years) were surgically treated for slab fractures of the third carpal bone. All fractures involved the articular surfaces of the intercarpal and the carpometacarpal joints in a frontal plane and had a cuboidal or slab shape. In 20 of the horses, the bone was fractured during racing and in 8 of the horses, the bone was fractured during race training. The right limb was affected more frequently than was the left limb (24 vs 7, P less than 0.05). Twenty-one (67.6%) horses raced at least once after recovery from the surgery. Data were av...
Spurlock GH.Seemingly, propagation of a dorsal cortical fracture in the third metacarpal bone developed after continued race performance in 2 horses. Historically, both horses had intermittent lameness that had responded to nonsteroidal anti-inflammatory drugs and brief rest periods. However, lameness in both horses had increased in severity. Radiography revealed a dorsal cortical fracture of the third metacarpal bone, with propagation of the fracture plane proximally. Fractures were incomplete and healed with stall rest in both horses.
Baker B, Gaffin SL, Wells M, Wessels BC, Brock-Utne JG.Endotoxins (lipopolysaccharides-LPS) and anti-endotoxin IgG antibodies were measured in racehorses before and after races of 1,000, 2,000 and 2,800 m. Results show that the mean plasma concentration of endotoxin increased significantly (p less than 0.02) while the anti-LPS IgG concentration decreased significantly (p less than 0.005) in all horses following the races. Pre-race and post-race anti-LPS IgG levels in racing-fit racehorses were significantly higher than in untrained horses (p less than 0.05). The possibility therefore exists that training-induced stress leads to leakage of LPS into...
Leach DH, Sprigings EJ, Laverty WH.Standard univariate and bivariate statistical methods and two multivariate methods, stepwise regression and factor analyses, were used to analyze 17 stride-timing measurements of 22 racing Thoroughbreds filmed at the beginning of races. All horses were in a right-lead transverse gallop. Data were extracted from frame-by-frame analysis of 16-mm film taken with a high-speed camera. The mean stride duration was 0.405 s and the mean stride frequency was 2.47 strides/s. Stride duration had a higher correlation to the suspension-phase duration (r = 0.864) than to stride-stance-phase duration (r = 0....
Ehrlich PJ, Dohoo IR, O'Callaghan MW.To document anatomic patterns of scintigraphic uptake and related orthopedic disease associated with racing activity in Standardbred horses. Methods: Retrospective study. Methods: 64 Standardbred horses evaluated for lameness. Methods: Medical records at the time of discharge were reviewed, and information regarding signalment; history; results of lameness examination, scintigraphy, and radiography; diagnosis; and treatment were obtained. Results: 274 areas of increased radiopharmaceutical uptake were identified. Scintigrams of 218 limbs (106 forelimbs, 112 hind limbs) were available for revie...
Maurer P, von den Driesch A.The present paper summarizes our recent investigations of the so-called horse books from the High Himalayas in Nepal. These books are written in tibetan language and are essentially dealing with hippology and hippiatry and to a lesser extent with topics such as pharmacology, anatomy, methods of diagnosis, divination and magical practices for horse races. The therapeutic methods of treatment in tibetan veterinary medicine are guided by the concepts of human medicine which, on the one hand, are related to the Ayurvedic System, on other hand, to the Traditional Chinese Medicine. Concerning the st...
Vilar JM, Spadari A, Billi V, Desini V, Santana A.This study was undertaken to characterize and establish the kinematic standards of Italian standardbred trotter horses in real racing conditions. Certain parameters, such as the angles of both front and hind fetlock joints, stride length, stride frequency and average speed in youngs and adults are presented, examinated and compared with statistical tests. The angles and stride length were obtained using ONTRACK software over frames extracted from two CANON MV630i digital videocameras. For the stride frequency, a third identical videocamera filmed the horses to count the number of beats per min...
Soroko M, Górniak W, Godlewska M, Howell K.The aim of this study was to evaluate the influence of training on body surface temperature over the joints in racehorses, measured by infrared thermography. The study involved monitoring of 14 Thoroughbred racehorses in 6 imaging sessions over a period of 3 months. Temperature measurements of the forelimb and hindlimb joints were made before and just after training. Joint temperature of limbs increased significantly after training. Environmental temperature had a statistically significant influence on surface temperature over the joints. The lowest surface temperatures were recorded over the ...
Knight PK, Thomson PC.OBJECTIVE Compare the career profiles of a cohort of Standardbred horses that first raced as 2-year-olds with those that started their racing careers at a later age. METHOD Retrospective analysis of the racing records of all foals born in New South Wales in the 2000 foaling season. RESULTS The career records of 999 horses were analysed. Almost half (43.9%) first raced as 2-year-olds and one-third (33.9%) as 3-year-olds. The median career duration for horses that first raced as 2-year-olds was 2.93 years (interquartile range (IQR) 2.70-3.16), which was significantly greater than the median for ...
Inoue S.Maternal aging has negative influences on the development and racing performance of their offspring in racehorses. However, the mechanism by which pregnancy at old age reduces the race performance of the offspring is unknown. Here, two hypotheses were posited: 1) Foals born to older mares are more likely to have muscular, skeletal, and cognitive disadvantages (direct effects). 2) Foals born to older mares are more likely to be affected by non-physiological factors correlating with the mare's age, such as the quality of sires (e.g. low-quality sires are likely to be chosen as partners of older ...
Ehrlich PJ, Seeherman HJ, Morris E, Kolias C, Cook WR.The effect of left recurrent laryngeal neuropathy (LRLN) on the metabolic cost of locomotion (MCL) and peak aerobic power (VO2peak) was evaluated in four trained Thoroughbred racehorses. Oxygen consumption (VO2), carbon dioxide production (VCO2), venous lactate concentrations (LAC), and heart rate (HR) were measured during a treadmill exercise test (TET). Each horse performed the exercise test four times, alternating between normal upper airway function and reversibly induced LRLN. Subcutaneous infusion of 2% mepivicaine, a local anesthetic, into the region were the left recurrent laryngeal ne...
Jiang Z, Chen JW, Haughan J, Stefanovski D, Soma LR, Robinson MA.Extracorporeal shockwave therapy (ESWT) is a treatment applied to musculoskeletal injuries in equine athletes to alleviate pain and accelerate healing. ESWT also causes acute tissue damage. Therefore, its ability to act as an analgesic and cause tissue damage potentially increases the risk of a catastrophic event if used shortly before a strenuous competition such as horseracing. While ESWT is prohibited by many racing jurisdictions within 10 days prior to competition, a test to detect whether a horse has received ESWT is needed. ESWT changes the protein levels of inflammatory mediators in bl...
Ramzan PHL, Wylie CE.Arthroscopy is considered the treatment of choice for dorsal osteochondral chip fractures of the metacarpo/metatarsophalangeal (MCP/MTP) joints in the racehorse; however, there is no published research on non-surgical management of this injury. Objective: To compare clinical features, intra-articular medication use and return to racing in Thoroughbred racehorses with non-surgically (non-SX) or surgically (SX) managed MCP/MTP dorsal chip fracture. Methods: Retrospective observational study conducted between 2006 and 2014. Methods: Radiographs of Thoroughbred racehorses were reviewed to identify...
Kasper DT, Gandy RF.The 2016 Equibase data set of American Quarter Horse starts in North America was analyzed, with the purpose of ranking the sires of the racehorses. A speed z-score derived from the race times and distances was used as a racing performance measure. Mixed effects models were used on various subsets of the data based on race distance and sire offspring number. The sire categorical variable was considered as a random effect. Various statistical criteria were used to optimize the model. The constructed models were then varied in terms of the random and fixed effects included, and the conditional mo...
Kritchevsky J, Olave C, Tinkler S, Tropf M, Ivester K, Forsythe L, Couetil L.The use of thyroid supplement is pervasive in athletic horses although its effects on measures of performance are not known. Objective: One purpose of this study was to determine whether supra-physiologic doses of levothyroxine affect the velocities at which blood lactate was greater than 4 mmol/L (VLa4 ) and heart rate was over 150 (V150 ) and 200 (V200 ) beats per minute respectively. Additionally, a survey of post-race blood samples was also conducted to determine whether high thyroxine concentrations were common in racehorses. Methods: A randomised, crossover, trial was performed in six h...
Raidal SL, Wright JD.Records of 220 thoroughbred horses presented to the Randwick Equine Centre or the University of Queensland Veterinary Teaching Hospital for surgical management of carpal injury were reviewed. Details of racing performance were obtained, enabling evaluation of racing success following surgery. Age and sex matched control horses not known to have suffered carpal injury were selected from the Australian Stud Book and the Australian Racehorse Register. Control and treated populations were compared in terms of overall career racing success. Radiographs or xeroradiographs from 198 horses were availa...
Constable PD, Tinkler SH, Couëtil LL.To determine the degree of agreement between 2 analyzers for measurement of total CO₂ concentration (ctCO₂) in equine plasma. Methods: 6 healthy untrained horses, 6 trained Standardbreds undergoing a simulated race protocol, and 135 trained Standardbreds at a racetrack. Methods: Jugular venous blood samples were obtained from all horses. Two analyzers (commonly used analyzer A and less expensive analyzer B) were used to measure plasma ctCO₂ in each sample. Validation of both analyzers was conducted in accordance with guidelines established by the Clinical and Laboratory Standards Institu...
Watt BC, Foerner JJ, Haines GR.To describe incomplete oblique sagittal dorsal cortical fractures of the equine third metacarpal bone, their surgical repair, and subsequent performance of the horses. Methods: Retrospective examination of medical records and racing performance. Methods: Six Thoroughbred race horses, 2 to 4 years of age. Methods: Radiographic confirmation of all fractures preceded general anesthesia and surgical correction. Three fractures were treated by intracortical compression using screws placed in lag fashion, and five fractures were treated by osteostixis. Race records were reviewed for each horse to de...
Markel MD, Wheat JD, Jang SS.Nine Thoroughbred racehorses were admitted with cellulitis (of one or more limbs) associated with coagulase-positive staphylococci. The right hindlimb was affected in 4 horses, the right forelimb in 2, the left hindlimb in 1, and both hindlimbs in 2. Typical abnormalities included high values for rectal temperature (9 horses) and heart rate (5 horses), hyperfibrinogenemia (7 horses), leukocytosis (7 horses), and neutrophilia (6 horses). The staphylococcal isolants were speciated in 3 horses and classified as Staphylococcus aureus. Complications included skin loss (5 horses), laminitis of the a...
Boorman S, Richardson DW, Hogan PM, Stefanovski D, Levine DG.To report the performance of thoroughbred racehorses after surgical repair of a medial condylar fracture of the third metacarpal/metatarsal bone. Methods: Retrospective cohort study. Methods: Forty-three horses surgically treated for medial condylar fractures, 30 with previous racing experience, 13 without previous racing experience (nonexperienced). Methods: Medical records (2009-2017) were reviewed for signalment, radiographic fracture characteristics, repair technique, and postoperative morbidity and mortality. Each experienced horse was matched with two horses randomly selected from its mo...
Gabel AA.During 1975 and 1976, 70 Standardbred horses with cunean bursitis-tarsitis were treated by cunean tenectomy or by more conservative approaches (rested, given corticosteroid injections in the cunean bursa and distal hock articulations, given an oral course of phenylbutazone, a combination of these) or were sold. In 1975, owners were urged to have cunean tenectomy done to horses that appeared to have potential to race well, and in 1976, the more conservative methods of management and treatment were recommended. Statistical analysis of racing performance data led to the conclusion that there was ...
Cogger N, Perkins N, Hodgson DR, Reid SW, Evans DL.To describe the impact of age, sex, and musculoskeletal (MS) injury on three preparation-level measures of performance: (i) the duration of preparation, (ii) time from the beginning of the preparation until the first start in a race or barrier trial, and (iii) time from the first start until the end of the preparation. Methods: Daily training and injury data for 2- and 3-year old Thoroughbred racehorses were collected fortnightly from 14 trainers in NSW, Australia. Training data were aggregated into units referred to as 'preparations'. Univariate and multivariate analytical methods were used t...
Martin GS, Strand E, Kearney MT.To determine the relationship between prediction errors of a regression model of racing finish times and earnings or finish position; the relationship between standardized finish times, determined by use of this model, and earnings or finish position; and whether this model was valid when applied to data for horses that underwent surgical treatment. Methods: Survey. Methods: Records of 6,700 healthy Thoroughbreds racing in Louisiana and of 31 Thoroughbreds with idiopathic left laryngeal hemiplegia that underwent surgical treatment. Methods: Predicted and standardized finish times were calculat...
Vermedal H, O'Leary JM, Fjordbakk CT, McAloon CG, Løkslett H, Stadsnes B, Fretheim-Kelly ZL, Strand E.The laryngeal tie-forward (LTF) procedure is commonly used to treat intermittent dorsal displacement of the soft palate (iDDSP). There is a wide range in reported efficacy of treating horses with and without a definitive diagnosis of iDDSP. Objective: To evaluate the racing performance of harness racehorses in which iDDSP had been definitely diagnosed and treated solely with the LTF procedure. Methods: Retrospective case series. Methods: Ninety-five harness racehorses were treated with LTF for confirmed iDDSP. A definite diagnosis of iDDSP was made with high-speed treadmill or overground endos...
Lin X, Zhou S, Wen L, Davie A, Yao X, Liu W, Zhang Y.Many studies have focused on identifying the genes or single nucleotide polymorphisms associated with the athletic ability of thoroughbreds, but few have considered differences in maternal and paternal heritability of athletic ability. Herein, we report on our association study of career race performances of 675 Australian thoroughbreds with their pedigrees. Racing performance data (prize money per start) were collected from the Bloodhound database. The performance of all horses was categorised as either poor or elite athletic achievement. Then, 675 foals were divided by their parents' perform...
Maxwell L, McCarrel TM, Hay S, Cole C.The antifibrinolytic agent aminocaproic acid (ACA) is occasionally used prior to episodes of intense training in racehorses suffering from exercise-induced pulmonary hemorrhage. Although a previous study indicated that the drug is cleared rapidly in horses, some racetrack practitioners claim that recent adverse analytical findings for ACA in postrace samples were from ACA administrations 5-7 days before the race. The purpose of this study was to re-examine the pharmacokinetics of ACA in horses to address this apparent conundrum. Eight exercise-conditioned thoroughbred horses were administere...
Tobin T, Watt DS, Kwiatkowski S, Tai HH, Blake JW, McDonald J, Prange CA, Wie S.We have introduced large scale non-isotopic immunoassay testing into pre- and post-race drug testing in racehorses. The technologies utilized are Particle Concentration Fluorescence Immuno Assay (PCFIA) and the one-step Enzyme Linked Immuno Sorbent Assay (ELISA). These technologies are rapid, inexpensive, and highly effective. On introduction into post-race testing in the Western United States, these ELISA tests exposed several previously undetected patterns of drug abuse. The drugs detected were buprenorphine, oxymorphone, mazindol, sufentanil and cocaine. This led to the suspension of a larg...
Brewer K, Machin J, Maylin G, Fenger C, Morales-Briceño A, Tobin T.Gabapentin, 1-(Aminomethyl)cyclohexaneacetic acid, MW 171.240, is a frequently prescribed high dose human medication that is also used recreationally. Gabapentin is orally absorbed; the dose can be 3,000 mg/day and it is excreted essentially unchanged in urine. Gabapentin is stable in the environment and routinely detected in urban wastewater. Gabapentin randomly transfers from humans to racing horses and is at times detected at pharmacologically ineffective / trace level concentrations in equine plasma and urine. In Ohio racing between January 2019 and July 2020,18 Gabapentin identifications...
Wood T, Tai CL, Taylor DG, Woods WE, Wang CJ, Houtz PK, Tai HH, Weckman TJ, Yang JM, Sturma L.Detomidine is a potent non-narcotic sedative agent which is currently in the process of being approved for veterinary clinical use in the United States. Since no effective screening method in horses is available for detomidine, we have developed an 125I radioimmunoassay for detomidine in equine blood and urine as part of a panel of tests for illegal drugs in performance horses. Our 125I radioimmunoassay has an I-50 for detomidine of approximately 2 ng/ml. Our assay shows limited cross-reactivity with the pharmacodynamically similar xylazine, but does not cross-react with acepromazine, epinephr...
Dintenfass L, Fu-lung L.Nineteen racehorses have been studied for haemorheologic factors as earlier studies showed a definite correlation between physical fitness and these factors in humans. Results included individual values for all viscosity factors, and the arithmetic means, the latter showing 4.70 +/- 0.49 cP for blood viscosity measured at a shear rate of 180 s-1; 1.100 +/- 0.048 cP for plasma viscosity; 1.045 +/- 0.063 for the rigidity of red cells defined by term 'Tk'; 42.2 +/- 4.1% haematocrit; 290 +/- 39 mg per 100 ml for fibrinogen level; and 278 +/- 75 mm h-1 for aggregation of red cells at 37 degrees C (...
Paine SW, Aldurdunji M, Garth-Greeves A, Muir T, Hincks PR.Hydroxyzine and cetirizine are first- and second-generation oral antihistamine drugs, respectively, used to treat allergic reactions in horses. Cetirizine is also a metabolite of hydroxyzine, which may lead to complexities in regulating their use in equine sporting events. The aim of the research was to be able to provide detection times (DT) from pharmacokinetic studies in thoroughbred horses to better inform trainers, and their veterinary surgeons, prescribing these substances for treatment of Thoroughbred racehorses. Six and two horses were given 9 repeated administrations of hydroxyzine HC...
Allen BV.The assay of serum folate has been used to investigate the folate status of thoroughbreds in training to race, in-foal thoroughbred mares at stud and crossbred ponies kept permanently at grass. Throughbreds in training, with no obvious haematological or clinical abnormalities, had lower serum folate levels (mean 3.3, range 1.5 to 6.1 microgram per litre) compared with thoroughbred mares at stud (mean 10.6, range 6.4 to 15.8 microgram per litre) and crossbred ponies at grass (mean 10.9, range 7.4 to 16.6 microgram per litre. Intensive exercise, over a period of six months, significantly decreas...
Cartoni GP, Montanaro M.The results and the improvement of the analytical procedures adopted for the control of doping in horses will be reported. This control has been systematically carried out in Italy for about 10 years in the laboratories of Italian Federation of Sport and Medicine in which the biological samples for the control of doping in various sport activities (football, cycling, athletics etc.) are also examined. In this way it is possible to use the same instruments for all these similar problems and compare the results. The analytical procedure is based on the following steps: 1) Extraction of the sampl...
