bluuebunny/crossref_metadata_2025_split huggingface dataset:
Accuracy of a Point‐of‐Care Lactate Analyzer for Measuring Blood and Plasma L‐Lactate Concentrations in Exercising Standardbreds
Authors: Constable P , Sulimai N , Tinkler S , Ko J , Couetil L 
Published: June 2014

IntroductionThe Accutrend® Lactate (formerly Accusport®) is a low cost point‐of‐care L‐lactate analyser. The analyser is widely used in the training of horses and has been used for research studies and to assist the clinical management of critically ill horses. The analyser is reported to be linear from 0.8–22.0 mmol/L (blood) and 0.7–26.0 mmol/L (plasma); however, test performance at high L‐lactate concentrations in equine blood and plasma has not been well documented. The purpose of this study was to determine the accuracy of the Accutrend® Lactate analyzer over a wide range of L‐lactate concentrations in paired blood and plasma samples.MethodsDuplicate jugular blood samples were collected from 8 trained Standardbreds before, during, and after a simulated race on a treadmill into 4 mL partially evacuated tubes containing lithium heparin. Blood and plasma L‐lactate concentrations were measured using a colorimetric lactate‐oxidase mediated reaction (BM‐Lactate® test strips and Accutrend® Lactate) and the reference enzymatic method (L‐lactic dehydrogenase spectrophotometry at 340 nm using samples deproteinized with 8% perchloric acid). Data was analysed using Deming regression and Bland‐Altman plots adjusted for repeated measures (P<0.05).ResultsThe reference method measured a wide range of L‐lactate concentrations in 128 blood (0.2–23.8 mmol/L) and 127 plasma (0.3–41.1 mmol/L) samples. The Accutrend® Lactate analyzer provided an accurate method of L‐lactate measurement, but only when blood and plasma L‐lactate concentrations were <12.5 mmol/L (79% of samples) and <15.0 mmol/L (64% of samples), respectively.ConclusionsBlood L‐lactate concentrations >12.5 mmol/L and plasma L‐lactate concentrations >15.0 mmol/L measured by the Accutrend® Lactate analyzer underestimate the true value by a variable amount when compared with the enzymatic reference method.Ethical Animal ResearchThe study was approved by the Institutional Animal Care and Use Committee at Purdue University. Sources of funding: Supported, in part, by a grant from the Indiana Horse Racing Commission. Competing interests: none.
Efficacy of Intravenous Dexamethasone Versus Placebo in Experimental Foot Lameness in Horses
Authors: Foreman C , Foreman J , Bergstrom B 
Published: June 2014

IntroductionThere are no refereed blinded controlled documentations of the skeletal analgesic efficacy of intravenous dexamethasone. The objective was to test the hypothesis that intravenous dexamethasone is more efficacious in alleviating lameness than placebo in a reversible adjustable heart bar shoe model of equine foot pain.MethodsEight healthy horses (7 Thoroughbreds, 1 Warmblood, aged 6.5 ± 3.3 years, age range 2–11 years) underwent weekly intravenous treatments 1 hour after lameness induction. Treatments were isotonic saline placebo at 1 ml/45 kg bwt, or dexamethasone (2 mg/ml in polyethylene glycol) at 0.045 mg/kg bwt, a typical dose used twice daily in the USA for anti‐inflammatory effect. Treatments were randomly assigned and administered by a co‐investigator who had no input on Heart Rate (HR) and Lameness Score (LS) measurements. Another investigator unaware of treatment assignments monitored HR and LS every 20 min for 5 hours after lameness induction and then hourly through 12 hours post‐treatment. One week later treatment assignments were reversed and the experiment was repeated. Repeated measures ANOVA and post hoc Tukey's test were used to identify significant effects at P<0.05.ResultsAfter treatment, mean HR and LS were not different between treatments (P>0.05). HR and LS remained elevated over pre‐lameness values throughout the 13‐hour post‐lameness monitoring period (P<0.05).ConclusionsIt was concluded that intravenous dexamethasone was no more effective than saline placebo. Neither treatment was effective at alleviating lameness over a 12‐hour post‐treatment period in this model. Dexamethasone at 0.045 mg/kg bwt should not affect acute foot lameness during equine exercise or performance.Ethical Animal ResearchThe study was approved by the University of Illinois Institutional Animal Care and Use Committee. Sources of funding: Fédération Equestre Internationale. Competing interests: none.
Chuckwagon Field Study: High‐Sensitivity Cardiac Troponin‐T Increases with Exercise But Is Not Correlated with the Presence of Arrhythmias During Exercise
Authors: Massie S , Leguillette R 
Published: June 2014

IntroductionIn chuckwagon racing, dubbed the “half‐mile of hell”, teams often race multiple consecutive days. Horses are in peak condition, however rare cases of sudden death attributed to cardiovascular failure occur. There are concerns regarding cumulative racing and its impact on the risk of sudden death. The objective was to determine if cumulative exercise affects integrity of the myocardium, assessed by high‐sensitivity troponin‐T (cTnT), and if the presence of arrhythmias during race or recovery affects plasma cTnT concentrations.MethodsHeart rate and electrical activity were recorded on 148 horses (9 ± 2.7 years) during racing days 1 and 2. 750 plasma samples were analysed (374 pre‐exercise, 376 post‐exercise) comparing cTnT before and after activity (paired t‐test). Associations between consecutive racing days, age and cTnT were analysed (ANOVA, Pearson Correlation). The relationship between arrhythmias and cTnT was also examined.ResultscTnT increased significantly with exercise (pre: 4.52 ng/L ± 0.17, post: 5.20 ng/L ± 0.23, P<0.001). However cTnt was not affected by cumulative exercise. A correlation between age and cTnT was found. 4235 arrhythmic events were recorded. No association existed between cTnT (post‐exercise) and the presence of arrhythmias during exercise and recovery.ConclusionsThis is the first study examining the effect of exercise on high‐sensitivity cTnT in horses and first large‐scale study on chuckwagon horses. Racing increases cTnT, however values remain low, suggesting myocardial damage of little clinical significance. Chuckwagon horses have long careers therefore age and cTnT could be further examined. cTnT was not affected by the presence of arrhythmias during exercise, indicating chuckwagon racing is well tolerated.Ethical Animal ResearchThe study was approved by the Veterinary Sciences Animal Care Committee of the University of Calgary (AC120049) and onwer informed consent was obtained. Sources of funding: Clinical Research Fund from the University of Calgary's Faculty of Veterinary Medicine. Summer Studentships were funded by NSERC. Competing interests: none.
Chuckwagon Field Study on 148 Horses: Racing Consecutive Days Affects Baseline Blood Electrolytes, pH and Lactate But Does Not Increase the Prevalence of Cardiac Arrhythmias
Authors: Massie S , Leguillette R 
Published: June 2014

IntroductionChuckwagon racing involves 4 Thoroughbred horses pulling a 600 kg wagon through a figure‐8 pattern and running a 1000 m dash. Horses can race four days in a row and there are concerns regarding the contribution of cumulative racing to electrolyte imbalances, arrhythmias, and sudden death, and its impact on recovery. The objective was to investigate the effects of cumulative racing on plasma electrolytes, lactate and prevalence of cardiac arrhythmias.Methods148 horses (9.0 ± 2.7 years) from 13 teams were monitored for heart rate and ECG activity on racing days 1 and 2. Differences in plasma electrolytes, pH and lactate (pre‐vs. post‐exercise and between days) were analysed (paired t‐test). Associations between electrolytes and the presence of arrhythmias during racing and recovery (Pearson correlation) were examined.Results377 ECGs (82 incomplete due to lost electrode) and 750 plasma samples (374 pre, 376 post) were analysed. 4235 arrhythmic events (21.6% warm‐up, 37.6% racing, 20.4% recovery) were recorded and were not different between days 1 and 2. They mainly comprised supraventricular premature contractions during warm‐up and racing (48% and 81.4% respectively) and ventricular premature contractions during recovery (29.2%). A significant association was found between post‐exercise electrolytes and the presence of arrhythmias during racing (P<0.001, r = 0.17). Consecutive racing significantly increased post‐exercise lactate on day 2 (P<0.001). Pre‐exercise pH and electrolytes were significantly different on day 2.ConclusionsAn association exists between post‐exercise electrolytes and occurrence of arrhythmias during consecutive racing, however it is of little clinical significance. Ventricular arrhythmias are as prevalent in chuckwagon horses as in other disciplines. Overall, repetitive racing is well tolerated.Ethical Animal ResearchThe study was approved by the Veterinary Sciences Animal Care Committee of the University of Calgary (AC120049) and owner informed consent was obtained. Sources of funding: Clinical Research Fund from the University of Calgary's Faculty of Veterinary Medicine. Summer Studentships were funded by NSERC. Competing interests: none.
Effects of Aerobic Training on Systolic, Diastolic and Mean Blood Pressure in Arabian Horses
Authors: Mirian M , Piffer ML , Bogossian PM , Fernandes WR 
Published: June 2014

IntroductionExercise causes several physiological changes resulting from autonomic and hemodynamic adaptations, but there are few reports about the behaviour of blood pressure (BP) during physical activity in horses, as well as the effect of training on BP.Methods9 untrained Arabian horses underwent two treadmill evaluations (before and after 90 days of aerobic training at 60% HRmax) at 6% incline with incremental speed increases every 3 minutes (commencing at 2.5 m/s and reaching 12.5 m/s). The facial artery was cannulated with a 20 G catheter and systolic blood pressure (SBP), mean (MAP) and diastolic (DBP) blood pressures were recorded with a multiparameter monitor (GE Dash 3000 model). Data were evaluated by two‐way ANOVA for repeated measures and Bonferroni multiple comparison (P<0.05).ResultsDuring initial evaluation SBP increased in a gradual and uniform manner as speed increased, reaching a maximum of 208 mmHg at a speed of 10 m/s. After training, SBP behaved similarly during treadmill evaluation, however values were lower until 10 m/s (P<0.001), and the maximum value of SBP obtained was 218 mmHg at 12.5 m/s. DPB was not significantly different (P = 0.124). MAP emulated the behaviour of SBP (P = 0.012).ConclusionsA decrease in SBP and MAP during identical treadmill evaluations before and after 90 days of aerobic exercise (60% HR max) indicated that training decreased cardiac effort required for the maintenance of physical activity.Ethical Animal Researchprocedures were approved by the University of São Paulo. Sources of funding: none declared. Competing interests: none.
Cardiopulmonary Function in Thoroughbred Horses Running Uphill and Downhill on an Inclined Treadmill
Authors: Ohmura H , Mukai K , Takahashi T , Aida H , Jones J 
Published: June 2014

IntroductionEccentric muscle contractions (“negative” work, e.g., downhill running) affect human skeletal muscle differently than concentric contractions, increasing muscle size and strength more than concentric exercise training with reduced oxygen consumption (VO2). Better understanding of skeletal muscle and cardiopulmonary responses to downhill training may indicate a role for this in Thoroughbred training. We hypothesised that Thoroughbreds would reduce metabolic energy cost and cardiopulmonary function when they ran at equivalent speed on a declined treadmill compared with running horizontally or uphill.MethodsFive well‐trained Thoroughbreds ran for 2‐min incremental exercise intervals on a treadmill at 1.7, 3.5, 6.0, 8.0 and 10.0 m/s on a +4% incline, 0% incline (horizontal) and −4% decline in random order on different days. Cardiopulmonary and O2‐transport variables were measured and analysed with two‐way repeated‐measures ANOVA and Holm‐Šidák pairwise‐comparisons.ResultsHorses ran at all inclines with identical stride frequency and length. At identical uphill speeds they had significantly higher (vs. horizontal) mass‐specific VO2 (43% mean increase) and CO2 production (VCO2/Mb), cardiac output (Q/Mb), heart rate, arterial CO2 tension (PaCO2), and reduced arterial O2 tension and saturation; tidal volume tended to be higher (P = 0.060). Downhill running reduced (vs. horizontal) VO2/Mb (19% mean decrease), VCO2/Mb, Q/Mb and PaCO2. Fractional energy cost increase (incline) and reduction (decline) decreased linearly with increasing speed.ConclusionsThoroughbreds run downhill with lower energy cost than on the level or uphill and the cost changes with speed. It remains to be determined if eccentric training induces skeletal muscle changes in horses.Ethical Animal ResearchThe study was approved by the Animal Welfare and Ethics Committee of the Equine Research Institute, Japan Racing Association. Sources of funding: none. Competing interests: none.
Validation of a Novel High‐Sensitivity Cardiac Troponin‐T Assay in Horses
Authors: Shields E , Passante S , Massie S , Seiden‐Long I , Leguillette R 
Published: June 2014

IntroductionCardiac troponin‐I (cTn‐I) has been previously validated in horses. Newer high sensitivity troponin assays have recently become available that are now the standard in human cardiology. The objective was to validate the high‐sensitivity cardiac troponin‐T (hscTn‐T) assay for use in horses and to determine the biological variation within and between horse breeds.MethodsSamples were analysed using the hscTn‐T assay reagent (Roche,Cobas c501). Method validation included linearity, lower limit of quantitation (LLQ), freeze‐thaw stability, within‐and between‐run precision, and comparison with cTn‐I (Abbott iSTAT, Deming regression). Normal range and biological variation included healthy horses (n = 120; age = 7.2 ± 0.5 years (SE)) representing 5 breeds.ResultsAssay was linear from 3–391 ng/L. The LLQ was validated at 3 ng/L. Stability of samples was unaffected by 3 freeze‐thaw cycles. Within‐run mean (±SD) was L1 = 6.50 (±0.97), L2 = 10.1 (±0.88), L3 = 15.3 (±0.82) ng/L and between‐run mean (±SD) was L1 = 12.2 (±1.03), L2 = 57.0 (±4.82), L3 = 256 (±23.1) ng/L. Comparison with cTn‐I assay showed excellent correlation (range: 8–3535 ng/L, r = 0.9998). Bias was evident in the regression results [hscTnT = (0.6153 ± 0.002809)*(cTnI*1000) − (11.53 ± 5.462)]. The 95th and 99th percentile of the normal distribution in healthy horses was 4 and 6 ng/L. Between breed, diurnal effect and between day variation was not detectable due to low concentrations of hscTnT.ConclusionsThis study established reference intervals for hscTn‐T assay in healthy horses and the performance characteristics of hsTn‐T assay in horse samples. Normal population distribution was mostly below the detection limit of the assay. The hscTn‐T assay will likely establish the standard in early detection of cardiac pathologies in horses.Ethical Animal ResearchThis study was approved by the Veterinary Sciences Animal Care Committee (protocol number AC12‐0049). Sources of funding: UCVM internship fund. Competing interests: none.
Description of a Field Exercise Test in Cross‐Bred Quarter Horses in Venezuela: Preliminary V200 and V170 Values
Authors: Zerpa H , Chacon T , Campos G 
Published: June 2014

IntroductionField exercise tests (FET) can assist design of individualized training programs. Although FETs have been used in other breeds, there are limited reports for Quarter horses (QH) and cross‐bred QH which are widely used in traditional Venezuelan equestrian activities. The aim of this study was to describe the implementation of an FET in cross‐bred Quarter horses in Venezuela.MethodsSix horses (3 stallions and 3 mares) performed a FET consisting of a four‐step incremental increase in speed (91 ± 10; 136 ± 3; 271 ± 20; 439 ± 43 m/min). Each cycle lasted 3 to 5 min with 3 minutes of rest between each. Environmental temperature was 32°C. Heart rate and speed were recorded (Polar Equine RS800CX®) and the speed to reach a heart rate of 200 and 170 beats/min was calculated by linear regression. The rate of heart rate decline was determined 5 minutes after the last step. Linear regression analysis, descriptive statistics and an unpaired t‐ test (Graph Pad Prism 5.0) were utilized to identify gender differences (P<0.05).ResultsGender did not influence the results. V200 and V170 were slightly higher in stallions (617 ± 98 and 465 ± 66 m/min, respectively) than in mares (511 ± 60 and 387 ± 60 m/min, respectively). The rate of heart rate decline was slightly more rapid in mares (25 ± 7 beats/min) compared to stallions (13 ± 5 beats/min).ConclusionsAlthough a low number of horses were evaluated, these preliminary data suggest that gender has limited influence on fitness of cross‐bred Quarter horses used in local Venezuelan equestrian activities under tropical environmental conditions. The mean V200 and V170 values obtained were lower than those reported for Thoroughbreds and Standardbreds, but similar to those reported in young racing Quarter horses.Ethical Animal ResearchThe study was approved by the Faculty of Veterinary Science, Central University of Venezuela Ethical Research Committee. Sources of funding: “San Antonio Farm” owned by Perez family and CDCH‐UCV (PG‐11‐8095‐2011). Competing interests: none.
Determination of Myofiber Types of Mangalarga Mares and Their Hybrids
Authors: D′angelis FHF , Santos EB , Ferraz GC , Andrade JM , Queiroz‐Neto A 
Published: June 2014

IntroductionThere are no published studies that characterize the different myofiber types of Mangalarga (ML) horses and hybrids. This study aimed to characterize and compare muscle fibers of the gluteus medius of ML mares and young and inactive mules resulting from the breeding of these mares with a Brazilian donkey.MethodsPercutaneous biopsies were performed in 11 mares and their foals (10 mules), at a depth of 60 mm. Fiber types were determined by comparing identical images using both the staining techniques of myofibrillar adenosine triphosphatase (mATPase) and nicotinamide adenine dinucleotide‐tetrazolium reductase (NADH‐TR). Stains for mATPase were pre‐incubated in acid medium followed by alkaline incubation. The frequency (F%) and relative total area (RTA%) of fiber types I, IIA and IIX were analysed. The cross‐sectional area (CSA, μm2) was quantified by the NADH‐TR technique. The means were compared using ANOVA followed by Tukey test (P<0.05).ResultsThe frequency of type IIA fibers was greater than types I and IIX. Type IIX fibers had higher CSA than I and IIA. The RTA of type IIX fibers was greater than type IIA fibers followed by type I. The higher RTA value of IIX fibers resulted from higher CSA. There was no difference between the variables for mares compared to the mules.ConclusionsML mares and mules that resulted from breeding with the Brazilian donkey have a high prevalence of type IIA fibers in the gluteus medius. This fatigue‐resistant fiber uses both metabolic pathways, glycolytic and oxidative, to obtain energy during muscle contraction, thus giving the ML mares and mules good performance in horseback riding, marching contests and endurance rides.Ethical Animal ResearchAll procedures were approved by the institutional animal care and use committee of the university (CEUA, Process: 01370/12). Sources of funding: Fundação de Amparo a Pesquisa do Estado de São Paulo. Process: 04655‐9/2012. Competing interests: none.
High‐Resolution Respirometry May Identify Early Indicators for Exertional Rhabdomyolysis in Standardbred Racehorses
Authors: Houben R , Leleu C , Fraipont A , Serteyn D , Votion D 
Published: June 2014

IntroductionDuring racing, mitochondrial oxidative phosphorylation (OXPHOS) is a major source of energy for muscle contraction. Assessment of muscle OXPHOS capacity by high‐resolution respirometry (HRR) might identify animals with altered energy metabolism and consequently increased risk of exertional rhabdomyolysis (ER).MethodsProspective cohort study. Ten healthy French Standardbreds in active training, aged 4–7 years, recruited at the start of a competitive racing season, underwent a standardised field exercise test with determination of speed at onset of lactate accumulation (VLa4) and measurement of serum creatine kinase activity (CK) two hours post‐exercise. Triceps brachii muscle microbiopsies were obtained for determination of OXPHOS and electron transfer system (ETS) capacities with HRR. Associations between HRR variables and occurrence of ER over the following four months of racing were analysed using univariate logistic regression.ResultsTwo horses developed ER during the study period: one within one month of recruitment, another presented multiple minor episodes over the season. For these ER horses OXPHOS/ETS ratio was lower, and Complex I/Complex I + II ratio and Complex I /Complex II ratio were higher than non‐affected horses in the study (perfect prediction of occurrence of ER with ratio of ≤0.74, ≥0.60 and ≥0.715 respectively). VLa4 for ER horses was within the range of non‐affected horses. Post‐exercise CK was within normal limits for all horses in the study.ConclusionsOXPHOS and ETS capacities and their derived ratios indicate dysfunctional muscle energy metabolism whereas VLa4 and CK were unremarkable in horses subsequently affected by ER.Ethical Animal ResearchThe study was approved by Liège University's Animal Ethics Committee (agreement N° 07‐629); owner informed consent was obtained. Sources of funding: Part of the study protocol was funded by Les Haras Nationaux (France). Competing interests: The Oxygraph‐2k HRR apparatus was provided on loan by OROBOROS Instruments (Innsbruck, Austria); there are no patents, products in development or marketed products to declare.