Performance horses are equines specifically trained and conditioned for activities that require a high level of athleticism, such as racing, dressage, show jumping, and eventing. These horses undergo specialized training regimens to enhance their physical capabilities, including speed, endurance, agility, and strength. The management of performance horses often involves tailored nutrition plans, regular veterinary care, and specific conditioning programs to optimize their performance and minimize the risk of injury. This topic covers peer-reviewed research studies and scholarly articles that explore the physiology, training methodologies, health management, and performance outcomes of these horses in various competitive disciplines.
Patterson-Kane JC, Firth EC, Goodship AE, Parry DA.To measure collagen fibril crimp angles and lengths as well as collagen fibril mass-average diameters in central and peripheral regions of the superficial digital flexor tendon of wild horses, to ascertain any age-related changes in either region in the absence of imposed galloping exercise. Methods: Measurements from a random cull of wild horses. Methods: Superficial digital flexor tendon samples were taken from 23 wild horses ranging in age from two to ten years. Methods: Horses were divided into 'young' (< 5 years, n = 10), 'middle-aged' (5 to < 10 years, n = 9) and 'ol...
Kozlov SA.The results of applying N. N. Sirotinin's concept of the use of hypoxic adaptation to enhance working capacity are given. There is evidence for the efficiency of adaptation of trotters to two hypoxias: to hypoxic hypoxia (in the midmountains) and to exercise hypoxia (during interval training under the conditions of Moscow) for increasing their performance. These studies demonstrated that in the midmountains, the trotters had more infrequent respiration, increased respiratory and minute respiratory volumes which were more obvious by the end of a monthly mountain stay. The monthly training of tr...
Jørgensen HS, Proschowsky H, Falk-Rønne J, Willeberg P, Hesselholt M.A retrospective cohort study was made of the racing performance of trotters which had been subjected routinely to radiography before they started training and racing. Sixty-one per cent (148) of the 243 horses, foaled in 3 consecutive years, had one or more abnormal findings categorised into 5 relevant groups based on radiography, of which osteochondrosis (OCD) was the most specific diagnosis. Parameters used to reflect racing performance were: proportion of horses starting in races, number of starts per year, earnings per year, earnings per start and racing longevity. No significant associati...
Roneus B, Andersson AM, Ekman S.Chronic synovitis may cause recurring lameness in competing race horses. Forty-five standardbred horses with recurring lameness secondary to chronic synovitis were studied. Arthroscopic synovectomy was performed in 32 metacarpo-/metatarsophalangeal joints and in 28 intercarpal joints of horses that had previously been treated unsuccessfully with commonly used intraarticular medication The outcome of the synovectomy was evaluated by comparing racing performance before and after surgery. The synovial membrane was microscopically characterized as chronic synovitis of varying severity. Racing perf...
Tetens J, Ross MW, Lloyd JW.To assess the effect of incomplete, midsagittal fractures of the proximal phalanx (P1) on racing performance in Standardbreds. Methods: Retrospective cohort study. Methods: 49 Standardbred horses admitted to the George D. Widener Hospital for Large Animals between July 1986 and December 1992 with a definitive radiographic diagnosis of an incomplete, midsagittal fracture of P1 and a known method of treatment. Methods: Performance index and racing time were compared before and after diagnosis and treatment of fracture, using ANOVA that controlled for the effects of horse, gender, age, track leng...
Hendrickson DA.The determination of poor performance in the young or unproven horse can be a difficult experience for the practitioner. This article describes an incremental exercise test that may be helpful in determining the cause of poor performance in horses when a complete physical examination and a lameness examination fail to elucidate the causes of poor performance. Included are values from normal yearling and 2-year-old horses that have undergone the incremental exercise test.
Parente EJ.The many testing methods available and the increasing sophistication of diagnostic equipment have enhanced greatly our capabilities to diagnose causes of exercise intolerance in the equine athlete during the last several years. High-speed treadmill examination has become the focus of this form of evaluation. Not all clinicians perform or have access to high-speed treadmill examinations. Testing methods that require the use of the high-speed treadmill, as well as methods that do not, are discussed.
Martin GS, Strand E, Kearney MT.To develop a statistical model to evaluate the influence of specific parameters on racing performance in Thoroughbreds. Methods: Survey. Methods: Racing records of Thoroughbreds performing in Louisiana from 1981 to 1985. Methods: Race results for 20 randomly selected days from 5 racetracks during 5 years were analyzed, using regression analysis. Results: The most influential parameter was distance raced. There were significant differences in racing performance among horses at different tracks. At the tracks examined, fast racing surfaces resulted in significantly faster finish times than good ...
Kobluk CN, Gross GM.This article deals with the presenting histories, clinical examinations, and therapies of the causes of poor performance and exercise intolerance in the western performance horse and the sprint racehorse. The veterinarian's ability to diagnose and treat various pathophysiologic conditions that affect these horses is crucial to the major goals of a return to optimal performance and a long athletic career. Although these horses are a significant portion of most veterinary practices, there exists a minimal amount of information on their clinical evaluation and treatment. This article intends to f...
Beard W.The respiratory system is a frequent cause of exercise intolerance in performance horses. Labored breathing, fatigue during performance, and prolonged recovery after exercise are common complaints. Inadequate fitness level and diseases of the cardiovascular system are differential diagnoses that share these complaints and should be ruled out. Generation of increased airway noise is a clinical sign that implicates the upper respiratory system. A careful history from the owner and endoscopy of the upper airway are the most useful diagnostic tools. Endoscopy during exercise on a treadmill is indi...
Moore BR.Lower respiratory tract disease is an important source of poor performance and exercise intolerance in racehorses and middle-aged sport horses. Horses that perform high-intensity exercise are predisposed to development of infectious and noninfectious respiratory disease. Diagnostic aids for investigation of lower respiratory tract disease include thorough thoracic auscultation with rebreathing, endoscopic examination, bronchoalveolar lavage (BAL), and thoracic radiographic examination. The therapeutic approach for horses with lower respiratory tract diseases often can be directed by cytologic ...
Gottlieb-Vedi M, Essén-Gustavsson B, Lindholm A.Five Standardbred trotters performed treadmill exercise with incrementally increasing trotting velocities for 2 min intervals in three different tests until fatigue. Each test was performed with draught loads of either 10, 20 or 30 kilopond (kp). Each trotting interval was followed by 2 min periods at a walk without draught load. Recordings were made of heart rate (HR), respiratory rate (RR), plasma lactate (PLA) and stride frequency (SF) at the end of each trotting interval. The HR increased to average values of 191 +/- 10,203 +/- 10 and 214 +/- 7 bpm and PLA increased to 3.8 +/- 0.7, 7.3 +/-...
Gaughan EM.Skeletal origins of exercise intolerance and performance failure can reside in multiple tissues. Diagnosis of injury that results in an ability to continue to exercise, yet inefficiently do so, requires familiarity with evaluation of subtle lameness and often with the specific demands of the different equine sports. Imaging is usually vital to diagnosis development and understanding of lesion influences on locomotion. Therapy is lesion dependent. Return to competitive exercise and performance is dictated by an understanding of skeletal tissue response to injury, rational progressive treatment,...
Flaminio MJ, Gaughan EM, Gillespie JR.Endurance competition requires synchronism and development of metabolic and musculoskeletal systems. An understanding of the existence of performance-limiting factors may permit the detection of exercise intolerance that could lead to performance failure, fatigue, and exhaustion. New concepts for assessment of fitness have increased the understanding of individual capacities and deficiencies and the interaction of the different systems involved in exercise.
Valberg SJ.The muscular system of the horse is remarkable in its athletic scope and capacity to adapt to the demands placed on it. Muscular fatigue often causes exercise intolerance in horses as a primary muscular dysfunction or secondary to abnormalities in other integrated systems such as the cardiovascular, respiratory, or skeletal system. This article reviews basic muscular physiology leading to a discussion of the physiologic causes of muscular fatigue. In addition, a review of pathologic muscle disorders such as muscle strains and exertional myopathies that lead to poor performance is provided.
Hancke J, Burgos R, Cáceres D, Brunetti F, Durigon A, Wikman G.Sport horses with long lasting high levels of gamma Glutamiltransferase (gGT) and Glutamic Oxalacetic Transaminase (GOT) and Creatinine Phosphokinase (CPK) and poor performance were administered during 14 days 3 g of Caval D'Or®, a standardized dried extract of Schizandra chinensis (fructus) orally. At day "0" the horses were divided into two groups: group 1 received a placebo and group 2 received Caval D'Or®. The results showed that Caval D'Or® is able to reduce significantly the levels of gGT and GOT in the serum at day 7 and 14 after administration. The CPK levels were also reduced by da...
Tyler CM, Golland LC, Evans DL, Hodgson DR, Rose RJ.Thirteen standardbred horses were trained as follows: phase 1 (endurance training, 7 wk), phase 2 (high-intensity training, 9 wk), phase 3 (overload training, 18 wk), and phase 4 (detraining, 12 wk). In phase 3, the horses were divided into two groups: overload training (OLT) and control (C). The OLT group exercised at greater intensities, frequencies, and durations than group C. Overtraining occurred after 31 wk of training and was defined as a significant decrease in treadmill run time in response to a standardized exercise test. In the OLT group, there was a significant decrease in body wei...
Weiss DJ, Geor RJ, Burger K.To determine whether pentoxifylline treatment altered hematologic, rheologic, electrolyte, or blood gas test results of Thoroughbreds during submaximal treadmill exercise. Methods: 5 healthy Thoroughbreds that had raced within the past year and had no history of exercise-induced pulmonary hemorrhage. Methods: Mixed venous blood samples were obtained before exercise, at treadmill speeds of 9 and 13 m/s, and 20 minutes after exercise; hematologic, rheologic, electrolyte, and blood gas test results were determined. Results: Pentoxifylline treatment resulted in a 45% reduction in RBC filtration pr...
Soma LR, Uboh CE, Nann L, Gerber AL.The administration of sodium bicarbonate (NaHCO3) or 'milk shakes' to Standardbred horses before racing is widespread. This study analysed nonrace day (CTL) and prerace venous acid-base values from Standardbred horses racing in Pennsylvania (PA) and New Jersey (NJ). Mean +/- s.d. CTL bicarbonate (HCO3) and base excess (BE) values, for a group of horses stabled during the 1993 racing season at Pocono Downs, Pennsylvania, were 28.6 +/- 1.9 and 2.6 +/- 1.7 mmol/l, respectively. In the same population of horses, mean +/- s.d. values for prerace HCO3- and BE values were 33.1 +/- 2.8 and 7.0 +/- 2.3...
Guhl A, Lindner A, von Wittke P.Eight thoroughbred horses, trained for racing competition, were subjected to a standardised incremental speed test to determine the relationship between their blood lactate concentrations and running speed. Between 14 days before and 14 days after completing the standardised exercise test, the horses were timed for runs of 2000 to 6000 m. The blood lactate concentration after each run was measured and compared with the blood lactate concentration predicted from the individual horse's blood lactate-running speed relationship curve determined from the standardised exercise test. The relationship...
Wagner PD, Erickson BK, Seaman J, Kubo K, Hiraga A, Kai M, Yamaya Y.Although the horse is considered an elite athlete with a specific VO2max some 2-4 times higher than man, maximal O2 transport is compromised both by moderately severe arterial desaturation and by failure to extract all O2 from blood perfusing exercising muscle. This prompted the present study to ascertain whether correction of arterial desaturation would proportionally augment VO2max and, if so, would O2 extraction behave in a manner predicted by diffusional transport limitation. Six two year old thoroughbreds were exercised to VO2max on a treadmill each on three separate occasions breathing g...
Ruggles AJ, Moore RM, Bertone AL, Schneider RK, Bailey MQ.To determine clinical signs, radiographic and scintigraphic findings, and performance outcome of racing Standardbreds with tibial stress fractures. Methods: Retrospective case series. Methods: 13 racing Standardbreds with tibial stress fractures. Methods: Information concerning clinical signs, diagnostic evaluation, and recommendations was obtained by review of the medical records. Performance information before and after diagnosis of the fracture was collected from racing records, and follow-up information was obtained from the owners or trainers by use of a telephone questionnaire. Results: ...
Scott CM, Marlin DJ, Schroter RC.Modification of a ventilated capsule technique for the measurement of sweating rate (SR) is described for application in an exercising horse. The plastic capsule was sealed against the coat of the horse. Dry air was blown through the capsule over the skin and the change in absolute humidity (g/m3) between air entering and leaving the capsule was used to calculate SR. The effect of flow rate on the response characteristics of the system was investigated and measured over a range of sweating rates in a group of horses completing a short exercise test. Repeatability of SR measurements made at 2 s...
Rivero JL, Henckel P.Biopsies were taken from three different depths of the gluteus medius muscle of 36 endurance horses aged between four and 17 years. Twenty of the horses were considered excellent performers according to their three fastest records in endurance events over the previous two or three years. The other 16 horses were moderate performers, with a mean racing speed < 3.5 ms-1 (in 120 to 180 km endurance rides), < 4.0 ms-1 (in 80 to 120 km endurance rides) or < 3.75 ms-1 (in 40 to 60 km endurance rides). The biopsy specimens were analysed for fibre type distribution (type I, IIA and IIB), fibr...
Schroter RC, Baylis E, Marlin DJ.Heart rate and gait characteristics (stride length and frequency) were studied in 6 horses subjected to a standardised incremental exercise test, involving moving at the trot and increasing speeds up to a fast gallop and subsequently during the steeplechase phase of a 3-day-event. The studies were performed in hot conditions. Appropriate scaling, based on hindleg length (hh), stride length (L), stride frequency (f) and speed (Sp) for nondimensional stride length (lambda = (L/hh), nondimensional stride frequency (phi = f(hh/g)1/2) and nondimensional velocity (û = Sp/(ghh)1/2), where g is the g...
Marlin DJ, Scott CM, Schroter RC, Mills PC, Harris RC, Harris PA, Orme CE, Roberts CA, Marr CM, Dyson SJ, Barrelet F.The aim of the present study was to determine the effect of different environmental conditions on physiological response to exercise. Four winter acclimatised, nonheat acclimated horses of different breeds were exercised at 20 degrees C/40% RH (CD), 30 degrees C/40% RH (HD) and 30 degrees C/80% RH (HH). The exercise test was designed to represent the structure and intensity of a One star Speed and Endurance test (competition exercise test [CET]). All 4 horses were able to complete the full CET (60 min + 30 min active recovery) in CD and HD, but only one horse completed the CET in HH. Two horse...
Foreman JH, Grubb TL, Benson GJ, Frey LP, Foglia RA, Griffin RL.This study was designed to characterise the acid-base and electrolyte effects of shortening the distance required during steeplechase (Phase B) in the face of hot and humid weather conditions during a treadmill-simulated Speed and Endurance test. Eight conditioned Thoroughbred horses underwent 3 randomised permutations of a standardised exercise test on a high speed treadmill. Each test consisted of trotting at 3.7 m/s for 10 min (Phase A); galloping at 11 m/s (Phase B) for 4 (cool laboratory conditions), 3 (hot and humid), or 2 (hot and humid) min; trotting at 3.7 m/s for 30 min (Phase C); an...
Kronfeld DS.Does dietary fat supplementation during conditioning improve athletic performance, especially in the heat? Fat adaptation has been used to increase energy density, decrease bowel bulk and faecal output and reduce health risks associated with hydrolysable carbohydrate overload. It may also reduce spontaneous activity and reactivity (excitability), increase fatty acid oxidation, reduce CO2 production and associated acidosis, enhance metabolic regulation of glycolysis, improve both aerobic and anaerobic performance and substantially reduce heat production. A thermochemical analysis of ATP generat...
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...
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...
Blanco MA, Di Rado FN, Peterson MM.Turfgrass in equine sports has clear advantages over other types of reinforcement but adds complexity to the management. This study investigates factors that influence the turfgrass' surface performance and how the use of a drainage package and a geotextile reinforcement affect quantitative measurements of turfgrass. The measurements are made using affordable, lightweight testing tools that are readily available or easily constructed. Eight boxes with turfgrass over a mix of the arena with peat at a consistent depth were tested for volumetric moisture content (VMC %) with time-domain reflectom...
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...
Funkquist P, Sandhagen B, Persson SG, Hedenstierna G, Essén-Gustavsson B, Nyman G.Five Standardbred trotters with red cell hypervolaemia (RCHV) were compared before and after removal of approximately 22% (36 ml/kg bwt) of the total blood volume in order to evaluate the haemodynamic responses, haemorheological alterations and oxygen transport during exercise to fatigue. Data were recorded during submaximal exercise at 4 different speeds on a treadmill and then during continued running at the highest speed step until fatigue. Oxygen uptake (VO2), pulmonary artery pressure (PAP), systemic artery pressure (SAP), heart rate (HR), haematocrit and haemoglobin concentrations (Hb) w...
van der Harst MR, Rijkenhuizen AB.The prognosis of ruptured collateral ligaments of the metacarpophalangeal or metatarsophalangeal joint in horses is usually considered to be poor, especially for future athletic performance. The main problem is the development, due to joint instability, of osteoarthritis, which may result in persistent lameness. In this paper a surgical technique is described in which joint stabilisation is realised by using a polypropylene mesh as a substitute for the ruptured ligaments, with the subsequent application of a cast for 7 weeks. The technique was successfully performed in 2 horses with ruptured l...
Nollet H, Deprez P.Since riders nowadays are expecting the highest level of performance from their horses, muscular disorders therefore represent a major problem for the equine athlete. A lot of research has been done to identify muscular disorders and their etiopathogenesis. Both acquired and inherited forms of muscle diseases have been described. In this review only the latter forms will be mentioned. Major signs of all muscle disorders are muscular stiffness, cramping or pain, muscular fasciculations, muscular atrophy and exercise intolerance. Muscle biopsies can help to identify the cause of rhabdomyolysis o...
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...
Rose RJ, Backhouse JW, Ilkiw JE.The electrocardiograms of 22 horses competing in a 3-day event were recorded before and after the event. In addition, blood samples were taken for determination of packed cell volume and total plasma protein before, during and after the speed and endurance phases (Day 2). The electrocardiograms of 13 horses showed various abnormalities before the event, most of which were T wave changes. As a result of competition in the event, there was a significant increase in the number of leads showing T wave abnormalities when the electrocardiograms taken before and after the event were compared. At all ...
van den Hoven R.Venous lactate concentrations were determined in standard-bred trotters following exercise of varying intensity to obtain a useful parameter in determining the working capacity of horses. After standard exercise, well-trained horses produced less lactate than did inadequately trained horses. During the post-exercise resting period, lactate disappeared faster from the blood in well-trained horses and young lightly trained horses than it did in poorly trained horses. Steady-state training resulted in lower lactate levels than those recorded after racing, whereas interval training resulted in the...
Southwood LL, Evans DL, Hodgson DR, Bryden WL, Rose RJ.The effects of roughage source on metabolism and exercise capacity were investigated using 6, previously conditioned, mature thoroughbred horses in a cross-over experiment. The horses were assigned to either non-alfalfa or alfalfa roughage diets which were isocaloric. The diets were fed for 2 weeks, after which the horses were exercise tested and then fed the alternate diet. Horses were exercised on a high-speed treadmill using a rapid incremental test. Arterial blood samples were collected for blood gas analysis and acid base measurements and venous blood samples for lactate and red blood cel...
Chu KK, Wang N, Stanley S, Cohen ND.The pharmacokinetic behavior of furosemide concentrations in performance horses is of great interest to the equine industry and equine researchers. Specifically, such information is useful for the evaluation of the existing guidelines in several racing jurisdictions and for the possible development of new guidelines for varying time periods after administration. We studied several approaches within the framework of nonlinear mixed effects models to increase the accuracy of evaluating these guidelines. Theoretical properties of the proposed methods were examined and the variances of the resulti...
Roneus B, Andersson AM, Ekman S.Chronic synovitis may cause recurring lameness in competing race horses. Forty-five standardbred horses with recurring lameness secondary to chronic synovitis were studied. Arthroscopic synovectomy was performed in 32 metacarpo-/metatarsophalangeal joints and in 28 intercarpal joints of horses that had previously been treated unsuccessfully with commonly used intraarticular medication The outcome of the synovectomy was evaluated by comparing racing performance before and after surgery. The synovial membrane was microscopically characterized as chronic synovitis of varying severity. Racing perf...
Couroucé A, Corde R, Valette JP, Cassiat G, Hodgson DR, Rose RJ.The purpose of this study was to determine the optimal treadmill slope for trotters to produce the same heart rate and blood lactate responses as on the track during a standardized exercise test. Nine 2-year-old French trotters performed exercise tests on a training track and on a treadmill set at an incline of 0, 2 or 4%. For all horses, track testing was performed on day 1 and then on the treadmill according to a Latin-square design. The track test utilized three steps each of 3 min at speeds of 470, 530, 590 m/min and the same speeds were used on the treadmill. Derived physiological variabl...
Ríha J, Minár J, Králík O, Krupa V.The adverse effect of blood-sucking dipterous insects (gadflies, gnats, black flies, midges) was determined and checked, as exerted on the working performance of draft horses working in forests; the possibilities of protecting horses with repellents were studied at the same time. The trial was conducted under field conditions in the territory of the Broumov Forest Establishment in the Náchod and Trutnov districts. A 10% water emulsion of the repellent, diethyltoluamide, was used; the horses were treated with the emulsion in a 24-hour interval. Over the seventy working days from the 1st of Jul...
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...
Rogers CW, Davies AS, Pfeiffer DU, Davie PS.To quantify the linear and temporal characteristics of the trot of 3-day event horses during the preliminary horse inspection of an advanced grade CCI*** 3-day event. Methods: A cross sectional study was made of the kinematics of 24 3-day-event horses during the first horse inspection at a CCI*** level S-day event. Video footage was digitised and linear and temporal measurements were made. Results: The horses trotted for an average of 10.44+/-1.55 strides. Spatial measurements were made on an average of 5.66+/-0.92 consecutive strides when the horses were within the calibration zone. The horse...
Pollock PJ, Kelly PG, Reardon RJ, Kelly GM.The objectives of this report were to describe the occurrence and features of dynamic ventrorostral displacement of the dorsal laryngeal mucosa (VRDDLM) in a group of Thoroughbred horses presented for investigation of poor performance and/or abnormal respiratory noise. Records from 600, dynamic, endoscopic examinations of the upper respiratory tract of horses were reviewed. Horses with VRDDLM were identified as those in which the dorsal laryngeal mucosa progressively obscured the interarytenoid notch and dorsoaxial portion of the corniculate processes of the arytenoid cartilages during high-sp...
Whitton RC, Kannegieter NJ, Rose RJ.To examine the relationship between medial palmar intercarpal ligament (MPICL) tearing and postoperative performance in racing horses. Methods: The postoperative performance of 42 horses in which the midcarpal joint was examined arthroscopically was followed prospectively. Intra-articular variables examined were the severity of MPICL tearing, subchondral bone damage and articular cartilage damage. Using a scoring system based on the class of race and the position in the race, a mean score was calculated for up to five races before and after surgery. The preoperative score was subtracted from t...
Caure S, Bonomelli N, Carro M, Leveillard D, Blanville F, Mortagne P, Cousty M, Weller R.Although the effects of both the surfaces and plantar angles on equine locomotion have been widely discussed, limited scientific data are available. Methods: Our objectives were to determine the effects of two surfaces (asphalt and sand) and of 3-degree hind toe or heel elevation on horse kinematics in an experimental study. Six saddle horses were shod with a reference shoeing (REF), characterized by a fore aluminium (REF F) and hind steel racehorse (REF H) shoeing. Two dimensional kinematic videos compared horse's kinematic parameters when walking and trotting on asphalt and sand. On asphalt,...
Quintanar MN, Millar TP, Burd MA.The limb of the equine athlete is subjected to all types of various stressors during exercise. To ensure the health of the horse and to prevent the possibility of lameness, it has been a common practice to apply cold therapy to the distal limb of the horse pre- and post-exercise. Commercially available boots are widely available for the application of cold therapy. To test the effectiveness of the boot, 6 healthy performance level sport type horses were exercised at a walk, trot, and canter in a round-pen and then subjected to the application of the ice boot for 20 minutes on a treatment leg, ...
Lewczuk D.The aim of the present study was to verify the influence of distance between obstacles in combination for free jumping test on linear and temporal kinematic parameters of the jump. Investigated groups of halfbred stallions being prepared for 100 days performance test (two groups, 36 horses in total) were filmed on different distances between main doublebarre obstacle and last cross-pole in the jumping lane. Both groups of horses were filmed during their regular work in the same training centre 1 week before performance test. Jumping parameters were obtained on the same size of the obstacle. Da...
Leung DKK, Wong ASY, Zhou QL, Wan TSM, Ho ENM.A non-target variable Data Independent Acquisition (vDIA) workflow based on accurate mass measurements using a Q Exactive OrbiTrap is presented for the first time for equine doping control testing. The vDIA workflow uses a combination of MS1 events (1 to 2) and multiple vDIA events to cover the analytes of interest. The workflow basically captures a digital image of a sample allowing all relevant MS1 and MS2 data to be recorded. In theory, the workflow can accommodate an unlimited number of analytes as long as they are amenable to the sample extraction protocol and fall within the mass limits ...
Southwood LL, Trotter GW, McIlwraith CW.To determine the outcome of horses after arthroscopic removal of abaxial fracture fragments of the proximal sesamoid bone and association of fracture grade with outcome. Methods: Retrospective study. Methods: 47 horses. Methods: Information obtained from dorsopalmar and dorsoplantar radiographic views of metacarpophalangeal and metatarsophalangeal joints was used to classify fractures as grade 1 ( 25 mm long) and type 1 (abaxial) and type 2 (apical-abaxial). Outcome was determined by whether the horse returned to its intended use, raced in the same class or higher (racehorses), or performed sa...
Michio Clark J, Connor TA, Post A, Blaine Hoshizaki T, Ní Annaidh A, Gilchrist MD.The performance of equestrian helmets to protect against brain injuries caused by fall impacts against compliant surfaces such as turf has not been studied widely. We characterize the kinematic response of simulated fall impacts to turf through field tests on horse racetracks and laboratory experiments. The kinematic response characteristics and ground stiffness at different going ratings (GRs) (standard measurement of racetrack condition) were obtained from 1 m and 2 m drop tests of an instrumented hemispherical impactor onto a turf racetrack. The "Hard" rating resulted in higher peak lin...
Kawahisa-Piquini G, Bass L, Pezzanite LM, Moorman VJ.The role of hoof morphology is increasingly recognized as a factor associated with lameness incidence in performance horses. The primary objective was to evaluate effect of training initiation on hoof unevenness in Quarter Horses (n = 42; 29 2-year-olds, 13 3-year-olds) over 6-months (m) in training (m0, m2, m4, and m6). Horses were objectively assessed for lameness (inertial sensor system) and photographs and radiographs of feet were taken. Hoof measurements were taken (palmar/plantar angles, frog base width/length, toe length/angle, heel length/angle, heel/foot width, wall height/angle), a...
Ronéus N, Essén-Gustavsson B.To determine whether performance capacity in a group of young trained Standardbreds is related to skeletal muscle characteristics and metabolic response to exercise. Methods: 13 clinically normal 2-year-old Standardbreds. Methods: Venous blood and middle gluteal muscle biopsy samples were obtained from each horse within 1 to 2 minutes after trotting at high speed for 1,600 m. Results: There was a positive correlation between plasma lactate and muscle glucose-6-phosphate (G-6-P) concentrations and trotting speed. There was a negative correlation between muscle adenosine triphosphate concentrati...
Knych HK, Stanley SD, Benson D, Arthur RM.Guaifenesin is an expectorant commonly used in performance horses to aid in the clearance of mucus from the airways. Guaifenesin is also a centrally acting skeletal muscle relaxant and as such is a prohibited drug with withdrawal necessary prior to competition. To the authors' knowledge, there are no reports in the literature describing single or multiple oral administrations of guaifenesin in the horse to determine a regulatory threshold and related withdrawal time. Therefore, the objective of the current study was to describe the pharmacokinetics of guaifenesin following oral administration ...
Henderson B, Bramlage LR, Koenig J, Monteith G.To assess the influence of humeral stress fracture location on the time to return to racing and postinjury performance of thoroughbred racehorses. Methods: Retrospective study (1992-2015). Methods: Thoroughbred racehorses (n = 131) that presented for lameness with the sole diagnosis of humeral stress fractures in the lame limb, as determined by scintigraphy or radiology. Methods: Sex, fracture site, age, starts, earnings, and average earnings per race were examined for differences in pre-stress and post-stress fracture diagnosis for the entire population as well as individual stress fracture l...