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All-In-One Vitamin & Mineral Pellet
Topic:Equine Health
Equine health encompasses the study and management of diseases, disorders, and overall well-being of horses. It involves understanding various physiological systems, preventive care, and treatment strategies to maintain optimal health in equine populations. Common areas of focus include nutrition, infectious diseases, orthopedic conditions, and reproductive health. Research in equine health aims to advance knowledge on diagnostic methods, therapeutic interventions, and management practices that improve horse welfare and performance. This page collects peer-reviewed research studies and scholarly articles that explore the diverse aspects of equine health, offering insights into current findings and advancements in the field.
A lactate-guided conditioning programme to improve endurance performance. Blood lactate measurements are used widely in horses to assess athletic performance, but there are few published data on using lactate as a guide for endurance improvement. The velocity at which blood lactate concentration ([LA]) of 4 mmol/l is reached (v4) is widely used to determine fitness. In an earlier study of v4, exercise at low intensities for longer duration was more effective at improving endurance than shorter, higher intensities. However, the prescription was unchanged during the study (6 weeks). We hypothesised that, to produce greater improvement in v4 in the same time frame, it ...
Speed associated with plasma pH, oxygen content, total protein and urea in an 80 km race. To test the hypothesis that endurance performance may be related quantitatively to changes in blood, we measured selected blood variables then determined their reference ranges and associations with speed during an 80 km race. The plan had 46 horses in a 2 x 2 factorial design testing a potassium-free electrolyte mix and a vitamin supplement. Blood samples were collected before the race, at 21, 37, 56 and 80 km, and 20 min after finishing, for assay of haematocrit, plasma pH, pO2, pCO2, [Na+], [K+], [Ca++], [Mg++], [Cl-], lactate, glucose, urea, cortisol, alpha-tocopherol, ascorbate, creatine ...
Effects on exercise metabolism of varying dietary starch and sugar proportions. Studies of the effect of varying dietary carbohydrate compositions on exercise metabolism of horses are scarce. In the present study, the starch and sugar proportions were altered in the diet to 4 Standardbred horses. In a crossover experiment, the horses were offered a hay and oat diet, where the oats were substituted for barley syrup (BS) at 4 levels (BS 0, 0.5, 1.0 and 1.5 kg). Each diet was consumed for 21 days and both an incremental treadmill exercise test (IE) and a 40 min submaximal exercise test (SE) were performed. During the IE there was a significant (P<0.05) increase in mean VO...
Changes in skeletal muscle GLUT4 content and muscle membrane glucose transport following 6 weeks of exercise training. This study examined changes in skeletal muscle GLUT4 content and glucose transport in isolated muscle membranes (GT) from horses before and 2 min after standardised submaximal exercise tests (SET) prior to and after completion of 6 weeks of training. Seven horses, age 3-9 years, body mass mean +/- s.e. 530 +/- 19 kg, and sedentary for at least 4 months, completed 6 weeks of training on a treadmill. An initial SET (UT) was performed on a 4 degree incline at a speed equivalent to 55% of pretraining VO2max and was repeated post-training at the same absolute workload (ABS). A third SET (REL) was p...
Metabolic responses to submaximal field exercise tests and relationships with racing performance in pacing Standardbreds. This study was undertaken to invesigate the application of submaximal field tests in assessment of performance. A submaximal field exercise test consisting of 2 bouts of pacing for 1600 m, with 5 min rest or walking between runs was performed on Standardbred racehorses at 2 training centres (A and B). Performance indices were compiled for each horse: number of race starts, number of race wins, number of race placings (1, 2 or 3), and lifetime earnings. Regression analysis was conducted to describe the relationship between plasma lactate concentrations and speed for tests one, 2 and pooled resu...
Forelimb skeletal scintigraphy responses in previously untrained Thoroughbreds undergoing initial treadmill training. Scintigraphy has been used in numerous clinical settings to examine horses to determine the origin of lameness problems, but it has not been used previously to monitor prospectively the skeletal responses of a group of similarly-trained racehorses. Our hypothesis was that in naïve Thoroughbred (TB) racehorses, initial treadmill training induces increased radiopharmaceutical uptake in high-motion joints and in the dorsal third metacarpal bone (MC3). Eight previously-untrained TB racehorses underwent sequential skeletal scintigraphic examinations as they exercised daily for 9 weeks on an inclin...
Effect of dorsal displacement of the soft palate on ventilation and airflow during high-intensity exercise. Dorsal displacement of the soft palate (DDSP) is one of the most common obstructive conditions of the upper respiratory tract in the racehorse. The present study was conducted to determine the effects of intermittent dorsal displacement of the soft palate (DDSP) on ventilation and respiratory airflow during high intensity exercise. Videoendoscopic recordings were made of the nasopharynx and larynx simultaneously with measurements of airflow and respiratory gas exchange, during high-speed treadmill exercise in 9 horses with confirmed intermittent DDSP admitted for clinical investigation of poor...
Chronic nodular panniculitis in a three-year-old mare. The clinical signs of chronic nodular panniculitis in a three-year-old mare were consistent with a diagnosis of sterile nodular panniculitis, but the mare had histopathological signs of both generalised steatitis and sterile nodular panniculitis. The mare was deficient in vitamin E and selenium.
Effect of trotting speed, load and incline on hindlimb stance-phase kinematics. The objective was to understand how the stance-phase kinematics of the hindlimb of trotting horses change with speed under 3 conditions (level, loaded and incline), to compare our results with the predictions of the spring-mass model and to help focus our future studies of muscle function. Video recordings were made of 5 Arabian horses trotting on a treadmill. Five consecutive strides were digitised and averaged for each trial. The angle-time diagrams were qualitatively similar to those reported previously. As speed increases, the range of motion of the hindlimb increases, as predicted by the ...
Effects of prolonged training, overtraining and detraining on skeletal muscle metabolites and enzymes. Thirteen Standardbred horses trained intensively for 34 weeks and detrained for 12 weeks to investigate the effects of training, overtraining and detraining on muscle metabolites, buffering capacity and enzyme activities (CS, HAD and LDH). After a standardised exercise test to fatigue at 10 m/s (approximately 100% VO2max), there was significant depletion of [ATP], [PCr] and muscle [glycogen] and accumulation of muscle and plasma [lactate], [NH3] and elevated muscle temperature. After training, associated with increased run time to fatigue (148%), there was reduced depletion of muscle [glycogen...
Effects of ageing and training on maximal heart rate and VO2max. The purpose of this study was to test the hypotheses that ageing would result in a decline in maximal heart rate (HRmax) and maximal aerobic capacity (VO2max) and, secondarily, that those effects would be reversible with training. Eighteen, healthy, unfit Standardbred mares representing 3 age groups: young (Y = mean +/- s.e. 6.8 +/- 0.4 years, n = 6); middle-aged (MA = 15.2 +/- 0.4 years, n = 6); and old (O = 27.0 +/- 0.2 years, n = 6) were used. HRmax, VO2max and oxygen pulse at VO2max (OPmax) and the velocities producing HRmax (VHRmax) and VO2max (VVO2max) were measured during pretraining an...
Modelling the oxygen cost of transport in competitions over ground of variable slope. This study provides an objective method for estimating the oxygen consumption of horses while running on variable slopes so that realistic comparisons may be made of the locomotory transport cost involved in 3-day events, particularly the Speed and Endurance Test, at sites of differing terrain. A knowledge of the work profile over a particular course would enable competitors to plan speed and interval times appropriately along its length. We have developed a semi-empirical, but mechanistically based, model to calculate the oxygen cost of transport [COTpath in ml O2/kg/m path] for running on th...
Hindlimb net joint energies during swing phase as a function of trotting velocity. Net joint powers and energies have been described in walking horses during the swing phase of the stride in the fore- and hindlimb (Clayton et al. 2001). During trotting, swing phase net joint powers have been described in the forelimb but not in the hindlimb. The effects of velocity on power profiles and energy patterns are important in relation to locomotor energetics. The objective of this study was to evaluate velocity-dependent changes in hindlimb net energy profiles of the swing phase during trotting. Inverse dynamic analysis was used to calculate net joint energies at the hindlimb joint...
Antioxidant status and muscle cell leakage during endurance exercise. Antioxidant status of 35 endurance horses was studied during an 80 (OD80) or 160 km (OD160) race. Packed cell volume (PCV), total plasma protein (TPP), plasma ascorbic acid (VIT C), plasma alpha-tocopherol (VIT E) and erythrocyte glutathione (GSH) concentrations, erythrocyte glutathione peroxidase (GPX), plasma aspartate aminotransferase (AST) and plasma creatine kinase (CK) activities were measured at 0, 40, 80 km and 60 min of recovery (REC) at OD80, and 0, 64, 106, 142, 160 km and REC at OD160. In both races, no changes were found in plasma VIT E concentration, but VIT C and GSH concentrati...
Influence of trotting and supplemental weight on metacarpal bone development. The use of weight-training to alter bone strength has not been investigated in horses. Recognising that bone responds to loading, we studied the effect of carrying weight on bone development during training. Seventeen horses were divided into 3 groups: controls exercised counterclockwise in a free-flow exerciser; the weight group performed the same exercise carrying progressively increasing weight up to 45 kg and the weight supplement group also received a myo-anabolic supplement. Radiographic equivalence measure of bone mineral content of zones of the third metacarpi (MCIII) was determined on...
Structural and oxidative enzyme characteristics of the diaphragm. During exercise, the horse can achieve oxygen uptakes and ventilations in excess of 200 ml/kg/min and 1800 l/min, respectively. Whether the diaphragm has the capacity to contribute substantially to inspiratory effort in the exercising horse is not known. To investigate the potential for the horse diaphragm to generate tension, lung displacement and sustain ventilatory function, we measured diaphragm thickness, muscle length and oxidative enzyme activity (citrate synthase) within the ventral, medial and dorsal costal and crural diaphragm. In the diaphragms of 6 mature horses (5 Thoroughbreds, o...
Postprandial glucose and insulin responses to a postexercise grain meal. Many studies have examined the effect of pre-exercise feeding on glucose and insulin responses of horses. The objective of this study was to determine whether exercise performed one hour prior to a meal would attenuate the glucose and insulin responses to a meal. Data collected from 8 mature geldings in a 2 period crossover design experiment were used to determine the postprandial glucose and insulin responses to a meal of oats offered 1 h postexercise. During each period, 4 horses received a test meal following a 14 h fast (NoEx) or a 14 h fast and exercise bout (PostEx) that consisted of 48 ...
Effect of exercise on plasma ferritin concentrations: implications for the measurement of iron status. Iron is of key importance for aerobic metabolism, and natural feeds of the horse are fairly rich sources of iron. Accordingly, the known incidence of iron deficiency anaemia is apparently rare in performance horses; despite this, iron deficiency in performance horses continues to be of concern to trainers and veterinarians. Effects of exercise on plasma ferritin concentrations were therefore studied in Standardbreds, Finnhorses and half-bred riding horses. Blood samples were taken after a moderate exercise test on a racetrack, a competition exercise test on a treadmill and a race. Even moderat...
The cost of transport in an extended trot. We hypothesised that trotters during an extended trot have lower energetic costs of locomotion (CT) than horses not bred for this behaviour. VO2 was measured as a function of speed in 7 Arabian horses (3 trained to extend their trotting speeds) and in 2 horses, of similar mass, bred to trot (Hackney). Both oxygen consumption and CT increased with speed and there was, contrary to our hypothesis, no difference between breeds. In Arabians at 6.5 m/s, CT had increased 25% above the CT at 5.0 m/s (normal transition speed). For Hackneys at 6.8 m/s, the CT was almost 35% higher. Stride frequencies in...
Effects of substituting starch with fat on the acid-base and mineral status of female horses. Feeding a high-fat diet may have potential advantages by maintaining pH homeostasis during intense exercise; conversely, effects including elevated PCV and increased plasma concentration of total protein may indicate effects detrimental to performance by reducing perfusion of tissues and organs. Six horses were used to determine the effects of an replacement of starch (diet '0.00') with 0.33, 0.67, 1.00 and 1.33 g soybean oil/kg bwt/day (diets '033', '0.67', '1.00' and '1.33') on venous and renal acid-base status and fractional clearance (FC) of electrolytes in a postprandial state but prior t...
Biomechanical implications of uphill training on the aetiology of tendinitis. It has been reported that a small decrease in the strain in the superficial digital flexor tendon (SDFT) occurs if the toe is raised during walking. Although walking on a slope appears similar to raising the toe, it is unclear whether uphill exercise decreases the strain in the SDFT. Because the force or strain on tendons is one of the important factors leading to tendon stress injury, we hypothesised that reducing the force in the SDFT during exercise may prevent tendinitis. The purpose of this study was to determine the effects of treadmill inclination on the force in the SDFT in the walking...
Oral L-carnitine combined with training promotes changes in skeletal muscle. The purpose of this study was to determine whether oral L-carnitine supplementation enhances the responses of skeletal muscle to training in seven 2-year-old Standardbreds. Four horses were supplemented with 10 g/day L-carnitine for 10 weeks and 3 horses served as controls. All horses were exercised regularly every second day on a treadmill for 5 weeks (training period) and housed in individual boxes for 5 additional weeks (detraining period). The training period consisted of 8 high- and 8 low-speed exercises carried out in alternating sequence. Gluteus medius muscle biopsies were taken at Wee...
Phosphorylation of protein tyrosine residues in fresh and cryopreserved stallion spermatozoa under capacitating conditions. Phosphorylation of tyrosine residues on sperm proteins is one important intracellular mechanism regulating sperm function that may be a meaningful indicator of capacitation. There is substantial evidence that cryopreservation promotes the capacitation of sperm and this cryocapacitation is frequently cited as one factor associated with the reduced longevity of cryopreserved sperm in the female reproductive tract. This study was designed to determine whether stallion sperm express different levels of tyrosine phosphorylation after in vitro capacitation and whether thawed sperm display similar ph...
Age-related changes and inheritance of lactate transport activity in red blood cells. In red blood cell membranes, the activity of the main lactate carrier, H+-monocarboxylate co-transporter (MCT), varies interindividually and its distribution is bimodal. To show the repeatability of MCT activity, 2 to 5 blood samples were taken, at an interval of approximately 1 year, from 51 Standardbred horses, age 2 weeks-8 years, for a total of 128 observations. The horses could be divided into low (LT) and high (HT) lactate transport activity groups. Age significantly affected (P<0.05) MCT activity such that activity was highest in foals, reached a nadir at 2-3 years, and tended to inc...
Influence of draw reins on ground reaction forces at the trot. According to riding texts, draw reins are supposed to support increased collection. This has not been measured objectively. Therefore, the objective of this study was to determine whether a horse ridden with draw reins would relatively increase weightbearing of the hindquarters while worked with the draw reins compared to a normal rein. Ground reaction forces were measured in 8 horses at the slow trot over a force plate in 3 different experimental set-ups: 1) riding with only a draw rein (DR); 2) riding with the combination of a normal and a draw rein (NR-DR) and 3) riding with a normal rein (...
Effect of instillation into lung of autologous blood on pulmonary function and tracheobronchial wash cytology. This study aimed at measuring the functional consequences and the pulmonary cytology changes following a simulation of pulmonary haemorrhage. Pulmonary function tests including lobeline-induced hyperventilation, cytology of tracheo-bronchial wash (TBW) and thoracic radiographs were performed before, as well as 1, 7, 14 and 28 days after, the instillation of 300 ml of blood into the lungs of 4 horses deemed free of exercise-induced pulmonary haemorrhage (Group 1). Control data (Group 2) were obtained by instilling the same volume of saline into the lungs of the same horses in a crossover design...
Evaluation of the i-STAT hand-held chemical analyser during treadmill and endurance exercise. This study examined the accuracy and precision of a hand-held, chemical analyser, i-STAT, in measuring selected blood constituents which may be of use in the diagnosis and management of metabolic disorders found in exercising horses. Venous blood samples were taken from 3 Thoroughbred geldings, fit and trained to exercise on a treadmill, both before and after exercise at a speed sufficient to elicit VO2max. The samples were analysed both with the i-STAT and with in-house analysers to compare the values of pH, partial pressure of oxygen (PO2), partial pressure of carbon dioxide (PCO2), bicarbon...
Potassium and lactate uptake by noncontracting tissue during strenuous exercise. Efflux of potassium (K+) and lactate (lac-) from active skeletal muscle during high intensity exercise leads to increased plasma [K+] and [lac-] in venous and arterial blood. The exercise-induced increases in these ions in human athletes is ameliorated, in part, by uptake by noncontracting tissue, reflected by an increase in the arteriovenous difference across these tissues from rest to exercise. To test the hypothesis that these ions are taken up by noncontracting tissue in strenuously exercising horses, plasma [K+] and [lac-] were measured in blood samples collected simultaneously from the c...
Comparison between glycerol and ethylene glycol for the cryopreservation of equine spermatozoa: semen quality assessment with standard analyses and with the hypoosmotic swelling test. The aims of this study were to compare glycerol (G) at customary concentrations and ethylene glycol (EG) as cryoprotectants for stallion semen in a skimmed milk (SM) extender, to test different EG concentrations and to compare the results of manual and computerized analysis with the hypoosmotic swelling (HOS) test. Ejaculates from two stallions were collected over 3 weeks (6 ejaculates per stallion), diluted in a SM based extender, divided into 4 fractions, centrifuged and diluted again to a concentration of 100 x 10(6) mL(-1) progressive motile spermatozoa (PMS) in addition with the cryoprote...
The effect of a tongue-tie in horses with dorsal displacement of the soft palate. Tongue-ties are frequently used in an attempt to prevent dorsal displacement of the soft palate (DDSP). The aim of this study was to determine the efficacy of a tongue-tie in horses clinically affected with the disorder. Videoendoscopic recordings and measurements of respiratory airflow were made simultaneously during high intensity treadmill exercise in 6 Thoroughbred racehorses with confirmed DDSP, with and without a tongue-tie. DDSP was confirmed in all 6 horses without the tongue-tie but occurred in only 4 horses with the tongue-tie in place. In one horse the palate displaced only on slowi...
