Exercise in horses encompasses the physical activities that horses engage in, either through natural behaviors or structured training programs. These activities impact a horse's musculoskeletal, cardiovascular, and respiratory systems, influencing overall health and performance. Exercise can vary in intensity, duration, and frequency, and its effects are studied to understand conditioning, endurance, and recovery processes in equines. Research in this field often focuses on the physiological adaptations to different types of exercise, the prevention of exercise-related injuries, and the optimization of training regimens for various equestrian disciplines. This page compiles peer-reviewed research studies and scholarly articles that explore the physiological, biomechanical, and health-related aspects of exercise in horses.
Le Moyec L, Robert C, Triba MN, Bouchemal N, Mach N, Rivière J, Zalachas-Rebours E, Barrey E.Endurance racing places high demands on energy metabolism pathways. Metabolomics can be used to investigate biochemical responses to endurance exercise in humans, laboratory animals, and horses. Although endurance horses have previously been assessed in the field (i.e., during races) using broad-window Nuclear Magnetic Resonance metabolomics, these studies included several different race locations, race distances, age classes, and race statuses (finisher or elimination). The present NMR metabolomics study focused on 40 endurance horses racing in three race categories over 90, 120, or 160 km. T...
Witkowska-Piłaszewicz O, Bąska P, Czopowicz M, Żmigrodzka M, Szczepaniak J, Szarska E, Winnicka A, Cywińska A.Sport training leads to adaptation to physical effort that is reflected by the changes in blood parameters. In equine endurance athletes, blood testing is accepted as a support in training, however, only the changes before versus after exercise in creatine phosphokinase activity (CPK) and basic blood parameters are usually measured. This study is the first longitudinal investigation of the changes in routinely measured blood parameters and, additionally, serum amyloid A (SAA), during seven months, in Arabian horses introduced to endurance training and competing in events for young horses. It h...
Piccolo L, Kienapfel K.Too much rein tension while riding may compromise the welfare of the horse. But who generates the tension on the reins-the horse or the rider? The primary aim of this pilot study was to evaluate the maximum rein tension that horses voluntarily maintain without a rider compared to rein tension with a rider. A secondary aim was to evaluate conflict behaviours in relation to rein tension. Thirteen horses were used, all fitted with customised "Animon" rein tension sensors (25 Hz, up to 600 N range), free-moving with side reins set in dressage competition frame with the noseline on the vertical. Re...
Gillen AM, Munsterman AS, Reid Hanson R. To report the outcomes of horses with suspected nephrosplenic entrapment (NSE) of the large colon treated by IV phenylephrine administration and exercise with and without trocarization (ie, medical management). Retrospective, observational study. 134 horses. Electronic medical records were searched to identify horses that underwent medical management for suspected NSE at a veterinary teaching hospital between 1995 and 2014. Demographic information, physical and ultrasonographic examination findings, treatment information (including the number of times the treatment was performed and patien...
Coelho CS, Adam GL, Agra de Omena E Silva G, Silva de Carvalho R, Cuña de Souza VR, Fazio F.Measurement of heart rate (HR) and velocity before, during, and after training exercises under field conditions indicates health and fitness level and intensity of imposed physical effort and allows rapid adjustments in training and nutritional protocols, improving welfare of athletic horses. The aim of this study was to monitor HR of Mangalarga Marchador horses during a marcha field test. Fifteen Mangalarga Marchador horses were evaluated during an aerobic exercise (marcha) for 40 minutes using a HR monitor system with GPS (Polar RS800CX-G3). Results were analyzed through Polar ProTrainer 5 ...
Page AE, Stewart JC, Fielding CL, Horohov DW.Previous work to evaluate various risk factors for failure to complete competitive endurance rides has examined clinicopathologic parameters, measurements of inflammation, and speed. Here, inflammatory markers were measured before, during, and after a long-distance, competitive endurance ride to examine the intraride dynamics of inflammatory marker expression and attempt to correlate those findings with whether a horse completed or failed to complete the ride. A total of 77 horses entered into the 2018 Tevis Cup Ride in California were enrolled in the study. Peripheral blood samples for mRNA i...
Luthersson N, Bolger C, Fores P, Barfoot C, Nelson S, Parkin T, Harris P.Diet is an accepted risk factor for equine squamous gastric disease (ESGD), but there is little published evidence for the benefit of dietary change (DC). This study evaluated the effect of DC with or without initial omeprazole medication. Twelve pairs of exercising horses with ESGD Grade 2/4 (EM) and 17 pairs with ESGD Grade ≥3/4 (ES), were monitored. Paired horses had similar management, feeding times, workloads, and initially feed or forage. One of each pair was randomly assigned, postgastroscopy (Scope1), to a specified restricted starch ration; the other remained on their original diet....
Crispe EJ, Lester GD.Exercise-induced pulmonary hemorrhage (EIPH) occurs commonly in horses undergoing strenuous exercise. Reported risk factors include racing in cold temperatures and wearing of bar shoes. In horses with documented moderate to severe EIPH, increasing the interval between races and adopting a negative race pace strategy may reduce the severity of EIPH in subsequent races. EIPH seems to have an impact on performance only when moderate to severe. This occurs in a small number of starters, approximately 6%. EIPH often is erratic in severity from race to race, although across a population it is weakly...
Dalla Costa E, Tranquillo V, Dai F, Minero M, Battini M, Mattiello S, Barbieri S, Ferrante V, Ferrari L, Zanella A, Canali E.Welfare of animals significantly depends on how stakeholders perceive their needs and behave in a way to favor production systems that promote better welfare outcomes. This study aimed at investigating stakeholders' perception of the welfare of equines, small ruminants, and turkeys using text mining analysis. A survey composed by open-ended questions referring to different aspects of animal welfare was carried out. Text mining analysis was performed. A total of 270 surveys were filled out (horses = 122, sheep = 81, goats = 36, turkeys = 18, donkeys = 13). The respondents (41% veterinarians) ca...
Curtiss AL, Parente EJ.To report an epiglottopexy technique for the treatment of epiglottic retroversion (ER) in 2 horses. Methods: Case report. Methods: A 2-year-old thoroughbred gelding and a 6-year-old standardbred gelding, both with ER. Methods: Epiglottic retroversion was diagnosed via exercising endoscopic examination in both horses. Epiglottopexy technique was performed in both cases. Results: Both horses returned to previous racing class within 1 year after surgery. Repeat exercising endoscopy of 1 horse 6 months postoperatively revealed resolution of the ER. Conclusions: Epiglottopexy should be consider...
Mami S, Khaje G, Shahriari A, Gooraninejad S.The aim of this study was to assay changes in blood biochemical parameters that resulted from exercise-induced muscle fatigue in horses participating in the two races (1,250 and 1,400 meters). Six male Arabian horses (3 to 6 years old) were used in this study. Blood samples were collected at time intervals including 1 hour before the race, immediately after the race, 1 and 24 hours after the end of race. Catalase (CAT), superoxide dismutase, glutathione peroxidase (GPX) activities, the blood level of malondialdehyde, protein carbonyl, and total antioxidant capacity (TAC) were measured, as w...
Strand E, Össurardóttir S, Wettre KB, Fjordbakk CT.To report clinical findings and performance in horses in which alar fold collapse (AFC) had been diagnosed and surgically treated and to assess form and degree of respiratory obstruction. Methods: Retrospective case series. Methods: Twenty-one standardbreds, 2 coldblooded trotter racehorses, 1 thoroughbred, and 1 Icelandic horse. Methods: Alar fold collapse was diagnosed on the basis of continuous abnormal expiratory flutter noise coinciding with filling of the false nostrils during exercise on a high-speed treadmill that was alleviated by suturing the alar folds (AF) temporarily in a dorsal p...
Soroko M, Śpitalniak-Bajerska K, Zaborski D, Poźniak B, Dudek K, Janczarek I.The aim of the study was to assess the effects of training on haematological and biochemical blood parameters as well as on the changes in body surface temperature in horses. In order to identify the predictive value of surface temperature measurements as a marker of animal's performance, their correlations with blood parameters were investigated. The study was carried out on nine horses divided into two groups: routinely ridden and never ridden. Infrared thermography was used to assess surface temperature changes before (BT) and just after training (JAT) on a treadmill. Seven regions of int...
Moore JL, Siciliano PD, Pratt-Phillips SE.Weight loss plans in horses typically use dietary restriction, but exercise may have additional benefits. This study aimed to compare the effects of a diet or exercise protocol resulting in comparable caloric restriction in obese horses. Ten obese horses were paired according to sex, age, and breed or breed type. One horse from each pair was randomly assigned to either diet (DIET)-intake restricted to approximately 85% of digestible energy requirements or exercise (EX)-exercised to expend approximately 15% of digestible energy requirements, resulting in 85% of requirements available, for 4 we...
Barton AK, Kershaw O, Gruber AD, Gehlen H.Recently, a syndrome called "equine idiopathic hemorrhagic cystitis" was described and clinical features compared with bladder neoplasia. In this case report, we describe a case of hemorrhagic cystitis with a favorable outcome in a high-performance dressage horse, in which exercise intensity might be the etiologic factor for the development of bladder-wall hyperplasia and hematuria. A 14-year-old Warmblood gelding was presented with a history of hematuria of 2-day duration. The high-level dressage horse had performed on the previous 3 weekends and was trained at least three times a week at per...
Dengel OH, Raymond-Pope CJ, Bosch TA, Oliver JM, Dengel DR.To examine measures of total and regional body composition using dual X-ray absorptiometry (DXA) in NCAA Division I collegiate equestrian athletes, 31 female collegiate equestrian athletes were matched to a population of normal controls by age and body mass index. Total and regional fat tissue mass (FM), lean tissue mass (LM), bone mineral density (BMD), and abdominal visceral adipose tissue (VAT) were measured by DXA. Equestrian athletes had a significantly (p=0.03) lower total body fat percentage (%fat) than controls. There were no significant differences in total LM and VAT between equestri...
Feeney E, Peal BT, Inglis JE, Su J, Nixon AJ, Bonassar LJ, Reesink HL.The objective of this study was to examine temporal variations in synovial fluid composition and lubrication following articular fracture. Post-traumatic osteoarthritis (PTOA) was induced by creating an osteochondral fracture in the middle carpal joint of four horses while the contralateral limb served as a sham-operated control. Horses were exercised on a high-speed treadmill, and synovial fluid was collected pre-operatively and at serial timepoints until 75 days post-operatively. Lubricin and hyaluronic acid (HA) concentrations were measured using sandwich ELISAs, and the molecular weight di...
Thompson DL, Valencia NA, Walker NL, Oberhaus EL.Five experiments were performed to test the hypothesis that α-melanocyte-stimulating hormone (MSH) is secreted in response to various stressors in horses similar to prolactin, growth hormone, and adrenocorticotropin (ACTH). There was considerable variation in resting concentrations of MSH and in the degree of stimulation in responders; thus all data sets were tested for heterogeneity of variance and corrected for as needed before analysis. In experiment 1, 12 mares were used in a switchback design to test the effect of a 2-minute exercise bout on MSH secretion. Plasma MSH concentrations were ...
Rajão MD, Leite CS, Nogueira K, Godoy RF, Lima EMM.The aim of this study was to understand the bone response against the exercise adaptations to reduce the occurrence of orthopedic injuries in endurance horses. To this end, the objective of the present work was to investigate how the bone adaptation on adult equines that were trained for 4-5 yr to endurance races responds to the long-term exercise of moderate intensity by comparing to non-athlete horses. For this purpose, 14 Arabian horses were selected and divided equally into two groups; a control group formed by animals that had never practiced physical activity nor been tamed and an exerci...
Durando MM.Horses have a high prevalence of resting arrhythmias, cardiac murmurs, and valvular regurgitation, and training can increase the prevalence. This makes it challenging for equine veterinarians who are asked to evaluate horses for poor performance to determine the clinical relevance of some findings. In addition, cardiac disease has the potential to cause collapse or sudden death, putting both the horse and rider at risk. Further diagnostics, such as echocardiograms and resting and exercising ECGs can help to sort out the impact of an abnormality found on resting physical examination. However un...
van Loon G.Arrhythmias are common in horses. Sinus arrhythmia and first- and second-degree atrioventricular block are frequently found physiologic arrhythmias, but should immediately disappear after stress or exercise. Atrial premature depolarizations are usually not associated with poor performance, but are a potential trigger for atrial fibrillation. Atrial fibrillation results in an abnormal ventricular response during exercise and poses a risk for collapse in some horses. This arrhythmia can usually be treated by quinidine sulfate or transvenous electrical cardioversion. Ventricular premature depolar...
Navas de Solis C.The physiology of exercise and training is fascinating, and hundreds of interesting studies have given insight into its mechanisms. Exercise testing is a useful clinical tool that can help veterinarians assess poor performance, fitness, and performance potential and prevent injuries. The clinically applicable aspects of cardiovascular adaptions to training and exercise testing are highlighted in this review. Different exercise tests should be used to evaluate horses performing in different disciplines and levels. Exercise tests that simultaneously assess several body systems can be beneficial ...
Redaelli V, Luzi F, Mazzola S, Bariffi GD, Zappaterra M, Nanni Costa L, Padalino B.The aim of this pilot study was to document the effects of endurance training at different intensities on heart rate (HR), blood count, serum cortisol, and maximal temperatures of different body locations, namely eye, crown, pastern pasterns, and muscle (, measured by infrared thermography technique (IRT) in horses trained for endurance. Possible associations among the studied parameters were also investigated. Our hypothesis was that temperature, measured by IRT after endurance training of different intensities would vary depending on the intensity and would be positively correlated with HR...
Ekman S, Lindahl A, Rüetschi U, Jansson A, Björkman K, Abrahamsson-Aurell K, Björnsdóttir S, Löfgren M, Hultén LM, Skiöldebrand E.Molecular serum markers that can identify early reversible osteoarthritis (OA) in horses are lacking. Objective: We studied serum concentrations of a novel cartilage oligomeric matrix protein (COMP) neo-epitope in horses subjected to short-term exercise and with acute lameness. The effects of circadian rhythm and age were also evaluated. Methods: Longitudinal studies in healthy horses and cross-sectional comparison of lame and non-lame horses. Methods: Sera were collected from five horses before and after short-term interval exercise and during full-day box rest. Sera from 32 acutely lame hors...
Broeckx SY, Pille F, Buntinx S, Van Brantegem L, Duchateau L, Oosterlinck M, Chiers K, Bertone AL, Spaas JH, Martens AM.OBJECTIVE To evaluate lameness and morphological changes associated with an osteochondral fragment-groove procedure as a means of experimental induction of metacarpophalangeal (MCP) joint osteoarthritis within an 11-week period in horses. ANIMALS 6 nonlame adult warmbloods. PROCEDURES The right MCP joint of each horse underwent an osteochondral fragment-groove procedure (day 0). After 1 week of stall rest (ie, starting day 7), each horse was trained daily on a treadmill. Weekly, horses underwent visual and inertial sensor-based assessments of lameness. Both MCP joints were assessed radiographi...
Bond SL, Greco-Otto P, Sides R, Kwong GPS, Léguillette R, Bayly WM.A prospective, randomized, controlled study was designed to determine relative aerobic and anaerobic (lactic and alactic) contributions at supramaximal exercise intensities using two different methods. Thoroughbred racehorses ( = 5) performed a maximal rate of oxygen consumption (V̇o) test and three supramaximal treadmill runs (105, 115, and 125% V̇o). Blood lactate concentration (BL) was measured at rest, every 15 s during runs, and 2, 5, 10, 20, 30, 40, 50, and 60 min postexercise. In , oxygen demand was calculated for each supramaximal intensity based on the V̇o test, and relative aerobi...
Van Steenkiste G, De Clercq D, Vera L, Decloedt A, van Loon G.Atrial tachycardia including focal atrial tachycardia and macroreentrant atrial tachycardia (atrial flutter), are occasionally found in horses. Diagnosis, treatment and follow-up of these arrhythmias has been inadequately described. Objective: To describe the findings on surface electrocardiography (ECG), intra-atrial electrogram recording and tissue Doppler imaging (TDI), the response to treatment by transvenous electrical cardioversion (TVEC), and TDI follow-up, of sustained atrial tachycardia in horses. Methods: Case series. Methods: Records from horses with sustained atrial tachycardia tre...
Hardeman AM, Serra Bragança FM, Swagemakers JH, van Weeren PR, Roepstorff L.Objective lameness assessment is gaining more importance in a clinical setting, necessitating availability of reference values. Objective: To investigate the between -path, -trial and -day variation, between and within horses, in the locomotion symmetry of horses in regular use that are perceived sound. Methods: Observational study with replicated measurement sessions. Methods: Twelve owner-sound horses were trotted on the straight line and on the lunge. Kinematic data were collected from these horses using 3D optical motion capture. Examinations were repeated on 12 occasions over the study wh...
Nolazco Sassot L, Villarino NF, Dasgupta N, Morrison JJ, Bayly WM, Gang D, Sanz MG.A comprehensive study of the effect of supramaximal exercise in lipid homeostasis of Thoroughbreds provides the basis for future research on the role of lipids on energy metabolism in racehorses. Objective: To compare the plasma lipidome of Thoroughbreds before and after supramaximal exercise using an untargeted lipidomics approach. Methods: Pilot experimental study. Methods: Four Thoroughbred horses were used. The maximal oxygen consumption (VO ) was calculated for each horse. Horses then underwent treadmill exercise at the speed for which the oxygen requirements had been calculated to be 11...
McKenzie EC, Valberg SJ, Godden SM, Finno CJ, Murphy MJ.To determine the effect of oral administration of dantrolene sodium on serum creatine kinase (CK) activity after exercise in horses with recurrent exertional rhabdomyolysis (RER). Methods: 2 healthy horses and 5 Thoroughbreds with RER. Methods: 3 horses received 2 doses of dantrolene (4, 6, or 8 mg/kg, p.o., with and without withdrawal of food) 2 days apart; 90 minutes after dosing, plasma dantrolene concentration was measured spectrofluorometrically. On the basis of these results, 5 Thoroughbreds with RER from which food was withheld received dantrolene (4 mg/kg) or an inert treatment (water ...
Michelotto PV, Muehlmann LA, Zanatta AL, Bieberbach EWR, Kryczyk M, Fernandes LC, Nishiyama A.This study investigated the putative roles of inflammation and platelet-activating factor (PAF) in exercise-induced pulmonary haemorrhage (EIPH). Two-year-old Thoroughbred colts (n=37) were exercised on a racetrack for 5months before commencement of the study. Each colt was then exercised at 15-16m/s over 800-1000m and broncho-alveolar lavage fluid (BALF) was collected 24h later. The colts were subsequently divided into two groups on the basis of BALF analysis; an EIPH-positive group (presence of haemosiderophages, n=23) and an EIPH-negative group (absence of haemosiderophages, n=14). BALF fro...
Piccolo L, Kienapfel K.Too much rein tension while riding may compromise the welfare of the horse. But who generates the tension on the reins-the horse or the rider? The primary aim of this pilot study was to evaluate the maximum rein tension that horses voluntarily maintain without a rider compared to rein tension with a rider. A secondary aim was to evaluate conflict behaviours in relation to rein tension. Thirteen horses were used, all fitted with customised "Animon" rein tension sensors (25 Hz, up to 600 N range), free-moving with side reins set in dressage competition frame with the noseline on the vertical. Re...
Art T, Amory H, Desmecht D, Lekeux P.This study investigated some physiological responses to exercise performed by a horse during show jumping. The effects of jumping on heart rate (HR), blood lactate (LA) and some other blood values were studied in nine normal horses participating at the Belgian Junior Championship. Venous blood was sampled before and immediately after the show jumping and was analysed for packed cell volume, LA, blood glucose (GLU), total plasma protein, bicarbonate, sodium, potassium (K+), chloride, calcium and activities of plasma lactate dehydrogenase, creatine phosphokinase (CK) aspartate amino transferase ...
Ringmark S, Jansson A, Lindholm A, Hedenström U, Roepstorff L.The aim of this study was to document effects of two high-intensity training regimes on horse health. Sixteen Standardbred horses in training from September as 1-year-olds with the goal to race as 3-year-olds were used in a 2.5 year study. Horses were trained in either a control training program (C-group) or in a program with 30% reduced high intensity distance compared to the C-group (R-group). Clinical examinations were performed nine times. Locomotion asymmetry was registered with a sensor-based system 17 times. There was no difference in health scores, locomotion asymmetry or veterinary tr...
Butudom P, Barnes DJ, Davis MW, Nielsen BD, Eberhart SW, Schott HC.To determine whether temperature of rehydration fluid influences voluntary rehydration by horses, six 2-3-year-old horses were dehydrated (4-5% body weight loss) by a combination of furosemide administration and 30 km of treadmill exercise. For the initial 5 min following exercise, horses were offered a 0.9% NaCl solution at 10, 20, or 30 degrees C. Subsequently, after washing and cooling out, voluntary intake of water at 10, 20, or 30 degrees C from 20 to 60 min after exercise was measured. Fluid intake (FI) during the first 5 min of recovery was 9.8+/-2.5,12.3+/-2.1 and 9.7+/-2.0L (p>0.05) f...
Rakesh V, Ducharme NG, Cheetham J, Datta AK, Pease AP.The necessary degree of arytenoid cartilage abduction (ACA) to restore airway patency at maximal exercise has not been determined. Objective: Use computational fluid dynamics modelling to measure the effects of different degrees of ACA on upper airway characteristics of horses during exercise. Objective: Maximal ACA by laryngoplasty is necessary to restore normal peak airflow and pressure in Thoroughbred racehorses with laryngeal hemiplegia. Methods: The upper airway was modeled with the left arytenoid in 3 different positions: maximal abduction; 88% cross-sectional area of the rima glottis; a...
Wilsher S, Allen WR.An opportunity to monitor equine chorionic gonadotrophin (eCG) production during 61 pregnancies in 25 Thoroughbred mares mated to the same Thoroughbred stallion was utilised in order to further knowledge regarding factors involved in the production of this hormone. Objective: To examine the effects of maternal body condition, exercise and parity on eCG production. Methods: In the first experiment, maiden mares were fed either a moderate (n = 9) or an excessive (n = 10) food intake throughout gestation. In the second experiment, 5 mares were exercised daily during pregnancy and eCG production r...
Matsuura A, Sakuma S, Irimajiri M, Hodate K.The aim of this study was to determine the loading capacity of a trotting Taishuh pony by gait analysis using a motion analysis system. Seven Taishuh Ponies (5 mares and 2 geldings) and their rider were fitted with a marker (70 mm in diameter placed on their chest) and recorded by 2 high-resolution digital DVD cameras (at a sampling frequency of 60 Hz) as they were trotting along a straight course. Each horse performed 7 tests: 1 test with a loaded weight of 70 kg, 5 tests with random loaded weights between 80 kg and 120 kg, and a final test with a loaded weight of 70 kg again. Three-dimension...
Theoret CL, Barber SM, Moyana T, Townsend HG, Archer JF.The reparative ability of equine synovium was determined by gross, histological, and ultrastructural examination. The functional potential of the synovium was estimated by examination of synovial cell organelles with transmission electron microscopy. Results from rested and exercised horses were compared to determine the effect of exercise on synovial healing. The response of synovectomized joint to exercise was evaluated with a standardized lameness examination and by gross, histological, and histochemical observations of the articular cartilage. A 7-mm diameter motorized synovial resector wa...
Avellini L, Silvestrelli M, Gaiti A.Oxidative stress develops when the generation of free radicals exceeds the antioxidant capacity of cells or extracellular fluids. It can also occur as a result of physical exercise, and the pathogenesis of exercise-induced myopathies and haemolysis in horses may be related to changes in lipid peroxidation caused by free radicals. Cells have developed biochemical protection against oxidative stress and, as tissues seem to increase their antioxidant defences under chronic activation, training may be one of the ways of increasing antioxidant defences. Accordingly, we tested some enzymatic antioxi...
Fonseca RG, Kenny DA, Hill EW, Katz LM.Fitness assessment can be challenging. The use of global positioning systems (GPS) with heart rate (HR) monitors has been promising; however, evaluation of speed parameters during training has not been reported. Objective: To evaluate speed indices during training in Thoroughbreds using a GPS-HR monitor. Methods: Thoroughbreds (n = 102) were assessed during training with data collected each work day (WD; sprinting). Speed indices evaluated included maximal velocity (V(max)), duration at V(max) (V(maxt)), acceleration rate (m/s(2)) from 800 m to V(max) (Acc800-V(max)), the distance (m) 6 (V(max...
van Harreveld PD, Lillich JD, Kawcak CE, Turner AS, Norrdin RW.To determine microradiographic appearance, bone histomorphometry, and mineral density of the long bones of the metacarpophalangeal joint in horses after immobilization followed by remobilization. Methods: 5 healthy horses. Methods: One forelimb of each horse was immobilized in a fiberglass cast for 7 weeks, followed by 8 weeks of increasing exercise. Calcein and oxytetracycline were administered IV during the immobilization and exercise phases, respectively, for bone labeling and analysis after euthanasia. Sagittal sections of metacarpal bones and proximal phalanges were examined via radiograp...
Conley KE, Jones C.We test the hypothesis that myoglobin is important for O2 supply near the oxidative capacity of muscle. This hypothesis is evaluated with a simple model that incorporates the properties of heart and skeletal muscle tissue taken from steers and horses exercising at their maximum O2 consumption rate. These tissue samples allowed us to set the bounds on oxidative demand and O2 flux from red blood cells to the core of the muscle fiber, to estimate the blood and tissue capacities for O2 diffusion, and to define the capillary blood PO2 driving this O2 flux. A model combining blood convection with ti...
MacKechnie-Guire R, Pfau T.High-level dressage horses regularly perform advanced movements, requiring coordination and force transmission between front and hind limbs across the thoracolumbosacral region. This study aimed at quantifying kinematic differences in dressage horses when ridden in sitting trot-i.e. with additional load applied in the thoracolumbar region-compared with trotting in-hand. Inertial sensors were glued on to the midline of the thoracic (T) and lumbar (L) spine at T5, T13, T18, L3 and middle of the left and right tubera sacrale of ten elite dressage horses (Mean±SD), age 11±1 years, height 1.70±0...
Bond SL, Greco-Otto P, Sides R, Kwong GPS, Léguillette R, Bayly WM.A prospective, randomized, controlled study was designed to determine relative aerobic and anaerobic (lactic and alactic) contributions at supramaximal exercise intensities using two different methods. Thoroughbred racehorses ( = 5) performed a maximal rate of oxygen consumption (V̇o) test and three supramaximal treadmill runs (105, 115, and 125% V̇o). Blood lactate concentration (BL) was measured at rest, every 15 s during runs, and 2, 5, 10, 20, 30, 40, 50, and 60 min postexercise. In , oxygen demand was calculated for each supramaximal intensity based on the V̇o test, and relative aerobi...
Räsänen LA, Wiitanen PA, Lilius EM, Hyyppä S, Pösö AR.Plasma concentration of uric acid, total peroxyl radical-trapping antioxidative parameter (TRAP), blood lactate concentration and plasma activity of xanthine oxidase (XO) were measured in six Standardbreed trotters after six bouts of exercise with increasing intensity on two separate days three days apart. Blood samples were taken immediately, 5, 10, 15, 30 and 60 min after each heat and 2, 4, and 6 hr after the last heat. Exercise caused an increase in TRAP and in the concentrations of lactate and uric acid. Plasma uric acid concentration increased exponentially with respect to time after the...
Morrice-West AV, Hitchens PL, Walmsley EA, Whitton RC.Little is known about the types of surfaces used during training of Thoroughbred racehorses or methods of exercise used in addition to ridden track-work. Our aims were to (1) describe the types of surfaces used in the training of Thoroughbred racehorses and to (2) identify alternative approaches used to exercise horses in addition to, or in place of, ridden overground track-work. Information regarding surface and alternative exercise methods was collected as part of an in-person survey of training practices of 66 registered Thoroughbred trainers in Victoria, Australia. Sand and synthetic surfa...
Karikoski NP, Box JR, Mykkänen AK, Kotiranta VV, Raekallio MR.The oral sugar test (OST) is commonly used to diagnose insulin dysregulation (ID) and equine metabolic syndrome; however, possible seasonal changes in OST results have not been evaluated. Objective: To determine the possible variation in insulin response to OST throughout the year and risk factors associated with maximum insulin concentration (InsMax) and ID. Methods: Prospective, longitudinal cohort study. Methods: The OST was performed on 29 Finnhorses every other month six times. Serum total adiponectin concentration and phenotypic variables related to obesity were also measured. Changes in...
Ghosh M, Cho HW, Park JW, Choi JY, Chung YH, Sharma N, Singh AK, Kim NE, Mongre RK, Huynh D, Jiao ZJ, Do KT, Lee HK, Song KD, Cho BW, Jeong D.The athletic abilities of the horse serve as a valuable model to understand the physiology and molecular mechanisms of adaptive responses to exercise. We analyzed differentially expressed genes in triceps brachii muscle tissues collected from Eonjena Taeyang and Jigusang Seryeok Thoroughbred horses and their co-expression networks in a large-scale RNA-sequence dataset comparing expression before and after exercise. High-quality horse transcriptome data were generated, with over 22 million 90-bp pair-end reads. By comparing the annotations, we found that MYH3, MPZ, and PDE8B genes in Eonjena Ta...
Shaktivesh S, Malekipour F, Whitton RC, Hitchens PL, Lee PV.Fatigue-induced subchondral bone (SCB) injuries are prevalent among athletes due to the repetitive application of high magnitude loads on joints during intense physical training. Existing fatigue studies on bone utilize a standard fatigue test approach by applying loads of a constant magnitude and frequency even though physiological/realistic loading is a combination of various load magnitudes and frequencies. Metal materials in implant and aerospace applications have been studied for fatigue behavior under physiological or realistic loading, however, no such study has been conducted on biolog...
Pan LG, Forster HV, Bisgard GE, Kaminski RP, Dorsey SM, Busch MA.We studied blood gases in ponies to assess the relationship of alveolar ventilation (VA) to pulmonary CO2 delivery during moderate treadmill exercise. In normal ponies for 1.8, 3, or 6 mph, respectively, partial pressure of CO2 in arterial blood (PaCO2) decreased maximally by 3.1, 4.4, and 5.7 Torr at 30-90 s of exercise and remained below rest by 1.4, 2.3, and 4.5 Torr during steady-state (4-8 min) exercise (P less than 0.01). Partial pressure of O2 in arterial blood (PaO2) and arterial pH, (pHa) also reflected hyperventilation. Mixed venus CO2 partial pressure (PVCO2) decreased 2.3 and 2.9 T...
Broeckx SY, Pille F, Buntinx S, Van Brantegem L, Duchateau L, Oosterlinck M, Chiers K, Bertone AL, Spaas JH, Martens AM.OBJECTIVE To evaluate lameness and morphological changes associated with an osteochondral fragment-groove procedure as a means of experimental induction of metacarpophalangeal (MCP) joint osteoarthritis within an 11-week period in horses. ANIMALS 6 nonlame adult warmbloods. PROCEDURES The right MCP joint of each horse underwent an osteochondral fragment-groove procedure (day 0). After 1 week of stall rest (ie, starting day 7), each horse was trained daily on a treadmill. Weekly, horses underwent visual and inertial sensor-based assessments of lameness. Both MCP joints were assessed radiographi...
Greve L, Dyson S.Major back dimension changes over time have been observed in some horses, the speed of which may be influenced by work type, skeletal maturity, nutrition and saddle fit. Currently, there are no longitudinal data quantifying changes in back dimensions. The objectives of this study were to quantify back dimension changes over time, to identify the effects of horse, saddle and rider on these dimensions, and to determine their association with season, weight, work and saddle management. A prospective, longitudinal study was performed, using stratified random sampling within a convenience sample of...
Frontiers in agingOctober 27, 2021
Volume 2 708918 doi: 10.3389/fragi.2021.708918
Latham CM, Owen RN, Dickson EC, Guy CP, White-Springer SH.In aged humans, low-intensity exercise increases mitochondrial density, function and oxidative capacity, decreases the prevalence of hybrid fibers, and increases lean muscle mass, but these adaptations have not been studied in aged horses. Effects of age and exercise training on muscle fiber type and size, satellite cell abundance, and mitochondrial volume density (citrate synthase activity; CS), function (cytochrome c oxidase activity; CCO), and integrative (per mg tissue) and intrinsic (per unit CS) oxidative capacities were evaluated in skeletal muscle from aged (n = 9; 22 ± 5 yr) and yea...
Mrugala D, Leatherwood JL, Morris EF, Dickson EC, Latham CM, Owen RN, Beverly MM, Kelley SF, White-Springer SH.Conjugated linoleic acid (CLA) improves oxidative stress and mitochondrial biogenesis in various species but has not been thoroughly investigated in horses. We collected blood and muscle samples from lightly exercising horses before and 6 and 12 wk after receiving either soybean oil (CON; n = 5) or CLA (CLA; n = 5) supplementation. Samples were analyzed for markers of mitochondrial characteristics, antioxidant status, oxidative stress, and muscle damage. Data were analyzed using a linear model with repeated measures. In the triceps brachii (TB), citrate synthase (CS) activity was higher in CON...
Marlin DJ, Allen JC.Knowledge of the competitive demands of different sports or activities is important for designing appropriate training programmes to ensure that animals reach a sufficient level of fitness to reduce the risk of overexertion and injury or illness and to achieve the best possible performance in relation to an individual's genetic potential. Whilst the physiological demands of many equestrian sports have been described, to the best of our knowledge the cardiovascular demands of polo have not. The aims of the present study were therefore to record heart rate during and after competitive polo games...
French DA, Barber SM, Leach DH, Doige CE.Arthroscopic surgery was performed on 12 horses (2-4 years of age) to create a 7 x 14 mm full-thickness cartilage defect in one radial carpal bone and in the contralateral third carpal bone. Six horses remained confined to a small paddock and six horses underwent a program of increasing exercise consisting of walking, trotting, and cantering for 13 weeks. All lesions showed evidence of healing at week 6 that progressed to more complete healing at week 13. There was no difference in the amount of repair tissue covering the defect. Histologically, the lesions healed with a combination of fibrous...
Valberg SJ, Velez-Irizarry D, Williams ZJ, Henry ML, Iglewski H, Herrick K, Fenger C.Certain Standardbred racehorses develop recurrent exertional rhabdomyolysis (RER-STD) for unknown reasons. We compared gluteal muscle histopathology and gene/protein expression between Standardbreds with a history of, but not currently experiencing rhabdomyolysis (N = 9), and race-trained controls (N = 7). Eight RER-STD had a few mature fibers with small internalized myonuclei, one out of nine had histologic evidence of regeneration and zero out of nine degeneration. However, RER-STD versus controls had 791/13,531 differentially expressed genes (DEG). The top three gene ontology (GO) enriched ...
Priest DT, Cheetham J, Regner AL, Mitchell L, Soderholm LV, Tamzali Y, Ducharme NG.Examination of the equine upper airway during racing has not previously been documented. Objective: To describe the feasibility and appearance of the upper airways by overground respiratory endoscopic examination during racing conditions. Methods: Overground videoendoscopic examinations were performed on 46 Standardbred racehorses during qualifying races. Examined horses' speeds were recorded throughout the race with a portable GPS device. Results: The procedure did not interfere with performance as there were no significant differences in race times between races in which horses were examined...
