Omneity® Pellets
All-In-One Vitamin & Mineral Pellet
Topic:Standardbred Horses
Standardbred horses are a breed known for their performance in harness racing, characterized by their ability to trot or pace at high speeds. This breed is distinguished by its well-muscled build, strong legs, and calm temperament. Standardbreds are primarily used in racing but are also versatile in other equestrian activities, including riding and driving. Their genetic lineage can be traced back to the late 18th century, with the establishment of the breed registry in the United States. This page compiles peer-reviewed research studies and scholarly articles that explore the genetics, physiology, and performance characteristics of Standardbred horses, as well as their management and health considerations in various equine disciplines.
Factors contributing to plasma TCO2 and acid-base state in Ontario Standardbred racehorses. Standardbred and Thoroughbred racehorses around the world are tested for performance enhancing substances. Among these are blood alkalising substances that raise plasma pH and total carbon dioxide (TCO(2)) concentration. However, many horses have an elevated TCO(2) due to dietary, environmental and health concerns without having been administered an alkalising substance. Objective: The purposes of this study were to determine the acid-base profile of a cross section of Standardbred horses in racing/race training in Ontario and the main independent variables that contributed to acid-base state....
Plasma aldosterone concentration and cardiovascular response to low sodium intake in horses in training. Horses in training lose large amounts of sodium but little is known about the cardiovascular response to low sodium intake. Objective: To investigate the effect of low sodium intake on plasma aldosterone (pAldo) concentrations and the cardiovascular system of athletic horses, and to identify markers of low sodium intake. Methods: Seven Standardbred geldings in training (trained twice a week) were randomly offered a standardised diet supplemented (NaS, 58 mg Na/kg bwt) and not supplemented (NaN, 3 mg Na/kg bwt) with NaCl for 5 weeks in a changeover design. Blood samples were taken once a week a...
Effects of training on equine muscle fibres and monocarboxylate transporters in young Coldblooded Trotters. Muscular changes caused by training are breed-specific and studies on the Norwegian-Swedish Coldblooded Trotter (NSCT) are limited. Knowledge about lactate-transporters in muscle in this light draught breed used for harness racing is lacking. Objective: To identify muscular changes associated with training in young NSCTs and investigate muscular distribution of the monocarboxylate transporter 1 (MCT1) and its ancillary protein CD147, which facilitate lactate transport across membranes. Methods: Nine horses were followed from the start of their training period until the end of their 3-year-old ...
Effects of crude protein intake from forage-only diets on muscle amino acids and glycogen levels in horses in training. There is little information about the influence of crude protein (CP) intake on glycogen and free pool amino acid concentrations in the muscle of horses in training. High energy forage-only diets may be an alternative to concentrate rich diets and may provide high levels of CP. Objective: To study the effect of feeding 2 forage-only diets, containing either high or moderate CP concentrations on glycogen and free pool amino acid concentrations in the muscle. Methods: Two high energy forage-only diets based on high-energy grass forage were fed for 23 days in a crossover design to 6 Standardbred ...
Exercise-induced increases in inflammatory cytokines in muscle and blood of horses. Studies have demonstrated increases in mRNA expression for inflammatory cytokines following exercise in horses and have suggested those markers of inflammation may play a role in delayed onset muscle soreness. However, measurement of mRNA expression in white blood cells is an indirect method. No studies to date have documented the cytokine response to exercise directly in muscle in horses. Objective: This study tested the hypothesis that exercise increases cytokine markers of inflammation in blood and muscle. Methods: Blood and muscle biopsies were obtained from 4 healthy, unfit Standardbred m...
Age related decreases in thermoregulation and cardiovascular function in horses. Older horses have an increased risk of hyperthermia due to impaired cardiovascular function. While many studies have investigated thermoregulation in horses during exercise, none have investigated the effects of ageing. Objective: To test the hypothesis that there is a difference in thermoregulation during exercise and plasma volume (PV) in young and old horses. Methods: Study 1: 6 young (Y, 7.7 ± 0.5 years) and 5 old (O, 26.0 ± 0.8 years) unfit Standardbred mares (507 ± 11 kg, mean ± s.e.) ran on a treadmill (6% grade, velocity calculated to generate a work rate of 1625 watts) until core ...
Effects of flunixin on cardiorespiratory, plasma lactate and stride length responses to intense treadmill exercise in Standardbred trotters. Since nonsteroidal anti-inflammatory drugs, such as flunixin, on account of their anti-inflammatory and analgesic properties, are used in both racing and equestrian sport horses, the question has been raised as to whether these drugs affect the physiological responses to exercise and thus performance potential. Objective: The aims of this investigation were to study the effects of flunixin on cardiorespiratory, metabolic and locomotor parameters in horses during intense treadmill exercise. Methods: Six Standardbred trotters underwent an incremental treadmill exercise test to fatigue, without d...
Evaluation of neuromuscular electrical stimulation on fibre characteristics and oxidative capacity in equine skeletal muscles. Neuromuscular electrical stimulation (NMES) is used to increase or maintain muscle strength during rehabilitation. Human studies investigating different protocols show that some treatments induce changes in muscle characteristics. Despite the frequent use of NMES in horses, no studies have been published describing its efficacy. Objective: To investigate the effects of a NMES protocol on equine fibre types and areas, glycogen concentrations and enzyme activities. Methods: NMES was administrated to m. gluteus medius and m. longissimus dorsi, on one side of 6 healthy Standardbred horses. The con...
Effects of prior exercise on insulin-mediated and noninsulin-mediated glucose uptake in horses during a hyperglycaemic clamp. There is limited information about factors regulating glucose utilisation post exercise in horses. Objective: To determine the effects of a single bout of moderate intensity exercise on measures of insulin-mediated (IMGU) and noninsulin-mediated (NIMGU) glucose uptake during a hyperglycaemic clamp (HC). Methods: Hyperglycaemic clamps were administered in random order to 8 Standardbreds under 4 conditions: 1) rest, insulinopenia (R-L); 2) rest, hyperinsulinaemia (R-H); 3) post exercise (45 min at ∼ 50% VO2peak), insulinopenia (Ex-L) and 4) post exercise, hyperinsulinaemia (Ex-H). In the R-L a...
Muscle characteristics in young Norwegian-Swedish Coldblooded Trotters and associations with breeding index, body size and early training. The trotting speed of Norwegian-Swedish Coldblooded Trotters (NSCTs) is, although inferior to Standardbred speeds, gradually increasing. This development is mainly attributed to breeding progresses. Characteristics of the middle gluteal muscle have recently been described in a small number of these horses but the actual spread in muscle parameters within the population is unknown. Objective: To describe the characteristics of the middle gluteal muscle and their naturally occurring variability in young NSCT horses and investigate possible association with body size, individual breeding index an...
Effects of feed deprivation on Standardbred horses fed a forage-only diet and a 50:50 forage-oats diet. A higher forage allowance to athletic horses might be an alternative to increase health and the gut fluid reservoir. However, more forage might increase bodyweight (bwt) and could therefore be a limitation during competition. Objective: To investigate the effect of a forage-only diet (FD) compared to a 50:50 (dry matter basis) forage:oats diet (OD) on bwt, plasma protein concentration and some metabolic plasma parameters during 12 h of feed deprivation. Methods: Twelve adult Standardbred horses in training were used. The 2 diets were fed in 2 experimental periods of 3 weeks each in a crossover...
Oxidative stress and antioxidant status in intensely exercising horses administered nutraceutical extracts. Many nutraceuticals are used as equine supplements without their efficacy having been scientifically tested. Black tea, cranberries, orange peel and ginger are a few of those nutraceuticals that warrant further study. Objective: To test the effects of single doses of black tea, cranberry, orange peel and ginger extract on markers of oxidative stress and antioxidant status following exercise in horses. Methods: In Study 1, 9 mature, healthy but unfit Standardbred mares were administered 2 l of a control (water), orange peel extract (30 g extract) or decaffeinated black tea extract (28 g extract...
Expression of lactate transporters MCT1, MCT2 and CD147 in the red blood cells of three horse breeds: Finnhorse, Standardbred and Thoroughbred. In exercising horses, up to 50% of blood lactate is taken up into red blood cells (RBCs). Lactate transporter proteins MCT1, MCT2 and CD147 (an ancillary protein for MCT1) are expressed in the equine RBC membrane. In Standardbreds (SB), lactate transport activity is bimodally distributed and correlates with the amount of MCT1 and CD147. About 75% of SB studied have high lactate transport activity in RBCs. In other breeds, the distribution of lactate transport activity is unknown. Objective: To study whether similar bimodal distribution of MCT1 and CD147 is present also in the racing Finnhorse ...
Morphological, haemato-biochemical and endocrine changes in young Standardbreds with ‘maladaptation’ to early training. The demands in the Standardbred trotters industry require young, still growing horses, to be trained well above light exercise level. During that period, the risk of occurrence of energy imbalance and maladaptation to training is high. In man, the lack of energy homeostasis is considered as the basic problem in the development of chronic fatigue. Objective: To find objective biomarkers of early maladaptation to training in young racehorses under field conditions. Methods: Sixty-five 2-year-old Standardbreds were followed during their first 3 months of training in 5 different training centres. ...
Biomechanical characterisation of equine laryngeal cartilage. Upper airway obstruction is a common problem in the performance horse as the soft tissues of the larynx collapse into the airway, yet there is a paucity of information on biomechanical properties for the structural cartilage components. Objective: To measure the geometry and compressive mechanical properties of the hyaline cartilage to improve understanding of laryngeal function and morphology. Methods: A total of 11 larynges were harvested from Thoroughbred and Standardbred racehorses. During gross dissection, linear dimensions of the cricoid were obtained. From both the cricoid and arytenoid...
Prevalence of Clostridium difficile in horses. Fecal samples were collected to establish the apparent prevalence of Clostridium difficile shedding in Standardbred and Thoroughbred racehorses housed at 4 racetracks and 2 breeding facilities, and in horses admitted to a referral large animal clinic. Forty-one (7.59%) of 540 racetrack horses, seven (5.83%) of 120 breeding farm horses, and four (4.88%) out of 82 horses admitted to the referral clinic were culture-positive for C. difficile. An overall fecal culture prevalence of 7.01% for C. difficile was identified in 742 fecal samples. PCR-ribotyping and toxin gene identification was performe...
Population studies of 17 equine STR for forensic and phylogenetic analysis. As a consequence of the close integration of horses into human society, equine DNA analysis has become relevant for forensic purposes. However, the information content of the equine Short Tandem Repeat (STR) loci commonly used for the identification or paternity testing has so far not been fully characterized. Population studies were performed for 17 polymorphic STR loci (AHT4, AHT5, ASB2, ASB17, ASB23, CA425, HMS1, HMS2, HMS3, HMS6, HMS7, HTG4, HTG6, HTG7, HTG10, LEX3 and VHL20) including 8641 horses representing 35 populations. The power of parental exclusion, polymorphic information content...
Plasma concentrations of testosterone and nandrolone in racing and nonracing intact male horses. Pennsylvania (PA) State Racing Commissions regulate the endogenous androgenic steroid, testosterone (TES), in racing intact males (RIM) by quantification of TES in post-race samples. Post-race plasma samples (2209) collected between March 2008 and November 2010 were analyzed for TES, nandrolone (NAN), and other anabolic steroids (ABS). Of the 2209 plasma samples, 2098 had quantifiable TES ≥ 25 pg/mL. Plasma (mean ± SD) concentrations of TES and NAN in RIM were 329.2 ± 266.4 and 96.0 ± 67.8 pg/mL, respectively. Only 64.6% of RIM had quantifiable concentration of NAN, and there was no relat...
Changes in hoof surface strain distribution in response to moderate exercise in Standardbreds. To quantify changes in hoof wall strain distribution associated with exercise and time in Standardbreds. Methods: 18 young adult Standardbreds. Methods: 9 horses were exercised 4 d/wk for 30 to 45 minutes at a medium trot for 4 months; 9 nonexercised horses served as the control group. Rosette strain gauges were used to measure the principal surface strains at the toe, lateral quarter of the hoof wall (LQ), and medial quarter of the hoof wall (MQ) of the right forefoot at the beginning and end of the experiment. Midstance maximal (msϵ1) and minimal (msϵ2) principal and peak minimal principal...
Equine laminitis: comparative histopathology 48 hours after experimental induction with insulin or alimentary oligofructose in standardbred horses. Laminitis has many triggers and comparing the histopathology of lesions induced by different causes may help to establish whether a common mechanism or multiple pathologies are involved. The aim of this study was to describe the microscopical lesions and to quantify morphometric changes in the lamellae of horses with insulin-induced (n=4) and oligofructose (OF)-induced laminitis (n=4) compared with normal controls (n=4). Archived lamellar samples collected during two previous studies were used. Laminitis was induced within 48 h in standardbred horses with either a euglycaemic, hyperinsulinaemi...
Physical, behavioral, endocrinologic, and cytogenetic evaluation of two Standardbred racehorses competing as mares with an intersex condition and high postrace serum testosterone concentrations. 2 Standardbred racehorses that had been winning races while competing as mares underwent postrace drug testing and had serum testosterone concentrations above the acceptable limit for female racehorses. Results: Initial physical examinations by the referring veterinarian revealed ambiguous external genitalia and suspected intra-abdominally located testes leading to a preliminary diagnosis of male pseudohermaphroditism. Horses were referred for further evaluation of sex. Physical examination of the external genitalia confirmed the findings of the referring veterinarian. Transrectal palpation an...
Quantification of left ventricular longitudinal strain, strain rate, velocity, and displacement in healthy horses by 2-dimensional speckle tracking. The quantification of equine left ventricular (LV) function is generally limited to short-axis M-mode measurements. However, LV deformation is 3-dimensional (3D) and consists of longitudinal shortening, circumferential shortening, and radial thickening. In human medicine, longitudinal motion is the best marker of subtle myocardial dysfunction. Objective: To evaluate the feasibility and reliability of 2-dimensional speckle tracking (2DST) for quantifying equine LV longitudinal function. Methods: Ten healthy untrained trotter horses; 9.6 ± 4.4 years; 509 ± 58 kg. Methods: Prospective study. Re...
Bronchoalveolar lavage fluid cytology and cytokine messenger ribonucleic Acid expression of racehorses with exercise intolerance and lower airway inflammation. There is limited information relating bronchoalveolar lavage (BAL) cytology and cytokine messenger ribonucleic acid (mRNA) expression in racehorses with inflammatory airway disease (IAD). HYPOTHESIS AND OBJECTIVE: We hypothesize that cytokine expression in BAL cells would correlate with cytology. Thus, we evaluated the mRNA expression of selected cytokines in BAL cells in racehorses with exercise intolerance and lower airway inflammation. Methods: Thirty-one client-owned Standardbred racehorses with exercise intolerance. Methods: Prospective, observational study. Cells were obtained by BAL, an...
The use of foal and studbook traits in the breeding programmes of Finnhorse and Standardbred trotters. Genetic correlations for body measurements and subjectively scored traits between foals and studbook horses were estimated using bivariate linear mixed models. Observations for nine foal and eleven studbook traits in Finnhorses on 6529 foals and 6596 studbook horses and in Standardbred trotters on 3069 foals and 2112 studbook horses were available from the Finnish horse breeding shows. The number of sires with progeny in both foal and studbook data was 203 in Finnhorse and 145 in Standardbred trotters. Estimates of heritability for body measurements in foals and studbook horses using univariat...
The timeline of lamellar basement membrane changes during equine laminitis development. The timing of lamellar basement membrane (BM) changes occurring during laminitis development is incompletely understood. Objective: To determine the temporal progression of lamellar BM changes and whether laminin-332 (Ln-332) γ2 cleavage products are generated during laminitis development. Methods: Eight clinically normal Standardbred horses were allocated into treatment (n = 5) or sham (n = 3) groups. The treatment group received, via nasogastric intubation, an oligofructose (OF) bolus (10 g/kg bwt) while the sham group was given water. Laminitis induction proceeded for 48 h followed by euth...
Treatment of epiglottic entrapment by transnasal axial division in standing sedated horses using a shielded hook bistoury. To report use of a shielded hook bistoury developed for correction of epiglottic fold entrapment in standing sedated horses. Methods: Prospective clinical study. Methods: Standardbreds (n=8), 3-19 years of age. Methods: Epiglottic fold entrapment was corrected during standing sedation using a shielded hook bistoury passed nasally into the pharynx. Owners, trainers, and referring veterinarians were contacted by telephone to establish outcome. Results: Axial division of the entrapping epiglottic fold was successful in all horses. No short- or long-term complications occurred. Axial transection o...
Electrosurgical tenoscopic desmotomy of the accessory ligament of the superficial digital flexor muscle (proximal check ligament) in horses. To report a tenoscopic technique using monopolar electrosurgery to transect the accessory ligament of superficial digital flexor muscle (AL-SDFM) and outcome in 33 horses. Methods: Case series. Methods: Horses (n=33). Methods: Medical files and surgery video recordings of horses that had AL-SDFM desmotomy performed by tenoscopy with monopolar electrosurgical electrodes were reviewed. Results: Of 33 horses, 24 were Standardbred racehorses with surgery performed bilaterally for superficial digital flexor tendonitis and 9 horses had flexural deformity. Severe (n=6) and mild (6) intrathecal hemorr...
Effects induced by exercise on lymphocyte β-adrenergic receptors and plasma catecholamine levels in performance horses. The effect of dynamic exercise on complete blood cell count, lymphocyte β-adrenergic receptor and plasma catecholamine (adrenaline and noradrenaline) levels in horses performing different disciplines were investigated during rest and after exercise. Blood samples were collected from jumping horses (n=6), Arabian Endurance horses (n=6) and Standardbred trotters (n=6) before and immediately after competition. Dynamic exercise caused a significant increase in red blood cell count (Standardbred trotters: P=0.0012), haemoglobin concentration (jumping horses: P=0.001; Standardbred trotters: P=0.01)...
Genome-wide association analysis of osteochondrosis of the tibiotarsal joint in Norwegian Standardbred trotters. Osteochondrosis (OC), a disturbance in the process of endochondral ossification, is by far the most important equine developmental orthopaedic disease and is also common in other domestic animals and humans. The purpose of this study was to identify quantitative trait loci (QTL) associated with osteochondrosis dissecans (OCD) at the intermediate ridge of the distal tibia in Norwegian Standardbred (SB) using the Illumina Equine SNP50 BeadChip whole-genome single-nucleotide polymorphism (SNP) assay. Radiographic data and blood samples were obtained from 464 SB yearlings. Based on the radiographi...
Morphological variation in the horse: defining complex traits of body size and shape. Horses, like many domesticated species, have been selected for broad variation in skeletal size. This variation is not only an interesting model of rapid evolutionary change during domestication, but is also directly applicable to the horse industry. Breeders select for complex traits like body size and skeletal conformation to improve marketability, function, soundness and performance in the show ring. Using a well-defined set of 35 measurements, we have identified and quantified skeletal variation in the horse species. We collected measurements from 1215 horses representing 65 breeds of dive...
