Omneity® Pellets
All-In-One Vitamin & Mineral Pellet
Topic:Metabolic Health
Metabolic health in horses refers to the physiological processes that manage energy production, utilization, and storage in equine bodies. These processes are critical for maintaining overall health, performance, and well-being. Metabolic health encompasses various aspects, including glucose metabolism, insulin sensitivity, and lipid regulation. Conditions such as Equine Metabolic Syndrome (EMS) and insulin dysregulation are common metabolic disorders that affect horses, impacting their ability to process and store energy efficiently. This topic compiles peer-reviewed research studies and scholarly articles that explore the mechanisms, diagnostic approaches, and management strategies related to metabolic health in horses.
Training programs. A training program is designed with the aim of developing the specific physiologic capabilities required to perform a certain type of exercise. Such capabilities involve the psychologic familiarity with, and acceptance of, the required tasks, the development of the neuromuscular coordination to perform these tasks optimally, and the utilization of energy by the working muscles. This article presents some basic principles for the design of training programs and offers ideas on how these principles may be applied to the conditioning of horses.
The organism as bioreactor. Interpretation of the reduction law of metabolism in terms of heterogeneous catalysis and fractal structure. Organisms and bioreactors are open, dissipative systems in steady state. They are functionally equivalent with respect to turnover and kinetics, and structurally analogous with respect to fractal organization and self-similar scaling. As heterogeneous catalytic systems both are governed by interaction of mass transport and reaction. The structural equivalent to turbulence in the reactor, yielding high efficiency, is the fractal folding and branching of the transport systems of the organism. Dimensionally and in terms of fractals, organisms and reactors are therefore area-volume hybrids. The ph...
Oral lactose tolerance test in foals: technique and normal values. Oral lactose tolerance tests were evaluated in 25 healthy foals (principals) assigned to 4 groups of approximately 1 week, 4 weeks, 8 weeks, and 12 weeks of age. Lactose monohydrate (1 g/kg of body weight [in a 20% water solution]) was administered via nasogastric tube after a 4-hour fast. Plasma glucose concentrations were monitored before dosing (0 minutes) and sequentially for 300 minutes. Six control foals were given a volume of water equivalent to the volume of lactose monohydrate administered to principal foals. After oral lactose loading, mean plasma glucose concentrations of all princi...
Inhibitory effects of intravenous chloramphenicol sodium succinate on the disposition of phenylbutazone in horses. The effects of i.v. chloramphenicol sodium succinate on the pharmacokinetics of i.v. phenylbutazone in six healthy adult horses were investigated. Administration of chloramphenicol sodium succinate to mares reduced mean (+/- SD) phenylbutazone clearance from 0.600 +/- 0.222 to 0.339 +/- 0.123 ml/min per kg and increased mean (+/- SD) half life from 244 +/- 59.8 to 371 +/- 80.8 min and mean residence time from 333 +/- 86.2 to 533 +/- 124 min. The mean steady-state volume of distribution of phenylbutazone was unchanged, with mean (+/- SD) values of 187 +/- 28.9 ml/kg in control animals and 170 +...
Activities of key enzymes of aerobic and anaerobic metabolism in middle gluteal muscle from trained and untrained horses. The effect of physical training on the in vitro activities of key enzymes that provide quantitative information on the maximum capacities of anaerobic and aerobic metabolism has been investigated in the gluteal muscle of the horse. Training had no effect on the activities of 6-phosphofructokinase or creatine kinase, suggesting that there was no effect on the capacity of anaerobic metabolism in this muscle. However, the activities of hexokinase and citrate synthase were increased, indicating that training increased the capacity of aerobic metabolism. For comparative purposes, muscle fibre compo...
Equine blood serum calcium and phosphorus concentrations in progressive nutritional hyperparathyroidism. Weekly blood serum samples from 20 yearling horses, divided into equal groups, receiving diets with total calcium to inorganic phosphorus ratios of 1,5/1 and 0,2/1, were analysed for calcium and phosphorus concentrations. This was done over a continuous 23 week period, divided into 2 sub-periods of 16 and 7 weeks each. During the first period complete diets were provided ad lib but were restricted during the second period to accentuate any effects of calcium deficiency and phosphorus excess. Falling calcium levels and rising phosphorus levels during period 1 and a reverse trend during period 2...
Enhanced prostacyclin biosynthesis and decreased thromboxane formation by 3-dimethylamino 5-(2′,6′-dichlorobenzylidene) 6-methyl (4H)-pyridazine (PC 89). The effects of 3-dimethylamino 5-(2',6'-dichlorobenzylidene) 6-methyl (4H)-pyridazine (PC 89) on the biosynthesis of PG I2 and TX A2 using horse aorta and horse platelet microsomes as sources of enzymes and arachidonic acid as substrate, were investigated. PC 89 (1.10(-6) M- 1.10(-3) M) dose-dependently - enhanced the biosynthesis of PG I2: the AD50 was 6.8 X 10(-6) M +/- 1.2 X 10(-9) M, the Vmax did not vary significantly with concentrations: PC 89 increased the affinity of enzyme for substrate - but inhibited TX A2 biosynthesis (ID50 = 3.31 X 10(-3) M +/- 4.8 X 10(-7) M): this inhibiting act...
Effects of altered ambient temperature on metabolic rate during CO2 inhalation. The purpose of this study was to determine if the changes in O2 consumption (VO2) during CO2 inhalation could in part be due to stimulation of thermogenesis for homeothermy. Twelve ponies were exposed for 30-min periods to inspired CO2 (PIco2) levels of less than 0.7, 14, 28, and 42 Torr during the winter at 5 (neutral) and 23 degrees C ambient temperatures (TA) and during the summer at 21 (neutral TA), 30, and 12 degrees C. Elevating TA in both seasons resulted in an increased pulmonary ventilation (VE) and breathing frequency (f) (P less than 0.01) but no significant increase in VO2 (P great...
Metabolic response of equine muscle to intermittent maximal exercise. Four thoroughbred horses performed 4 gallops (G1-G4) with intervals of 5 min. With one exception, gallops were sustained at maximal speed over 620 m. Muscle biopsy samples of the middle gluteal and brachiocephalicus were taken before, during, and after exercise and assayed for ATP and intermediary metabolites. The results showed a major involvement of the brachiocephalicus, in addition to the middle gluteal, during galloping. In three horses, who were clearly fatigued, muscle ATP decreased by up to 50% by the end of G4. This was matched by an equal rise in inosine 5'-monophosphate. Pronounced ...
Current concepts of hyperlipaemia in horses and ponies. Hyperlipaemia is an important condition in ponies, not just because of the seriousness of the clinical signs and biochemical changes involved, but because of the distress it causes owners and breeders that have had animals suffer from it. Hyperlipaemia occurs most commonly in fat ponies in late pregnancy and is rarely seen in larger horses. The syndrome has similarities with conditions in other species but the definitive aetiologies are not yet known. The condition in ponies is undoubtedly related to stress. The biochemical mechanisms involved in equine hyperlipaemia are considered and an hypo...
The effect of training and physical exercise on the energetic metabolism of equine erythrocytes. Erythrocytes, due to their simple metabolic processes, differ greatly from nucleated
cells. Their main metabolite of glycolysis is 2,3-Diphosphoglycerate (2,3-DPG), which
serves also as an energy store for producing ATP in the pyruvate kinase reaction. 2,3-DPG
modifies also the affinity of haemoglobin for oxygen (4). Increase in the concentration of
2,3-DPG, ATP and body temperature, or a decrease in the pH value of blood causes
decreased affinity of haemoglobin for oxygen as blood transverses muscle capillaries,
facilitating oxygen delivery. In equine erythrocytes, the level of ATP is s...
Effects of dietary energy supply on serum thyroxine, tri-iodothyronine and insulin concentrations in young horses. The effects of meal ingestion on the circulating concentrations of the growth-regulating hormones thyroxine (T4), tri-iodothyronine (T3) and insulin were examined in weanling Thoroughbreds fed 70% (diet A), 100% (diet B) or 130% (diet C) of their energy and protein requirements. Peak insulin concentrations occurred 1, 2 and 3 h after the ingestion of diets C, B and A respectively. Increases in plasma glucose concentrations preceded the increases in serum insulin concentrations. Serum T4 concentrations increased after the ingestion of diets A and B and decreased after diet C. In contrast, serum...
Metabolic investigations of fibroblasts from horses, Equus caballus, with hereditary severe combined immunodeficiency. In an attempt to determine the metabolic defect causing severe combined immunodeficiency (SCID) in horses in which altered purine metabolism has been observed, various parameters of purine and pyrimidine metabolism were evaluated. The activities of nine purine enzymes (adenosine kinase, purine nucleoside phosphorylase, deoxyadenosine kinase, deoxycytidine kinase, 5'-nucleotidase, AMP deaminase, hypoxanthine-guanine phosphoribosyl transferase, and adenine phosphoribosyl transferase were measured in fibroblasts. All activities determined for SCID horses were normal. Uptake of 10 microM adenosine...
Unfolding-refolding transition of a hinge bending enzyme: horse muscle phosphoglycerate kinase induced by guanidine hydrochloride. The unfolding-refolding transition of horse muscle phosphoglycerate kinase induced by guanidine hydrochloride was studied under equilibrium conditions using four different signals: fluorescence intensity at 336 nm, UV difference absorbance at 286 and 292 nm, ellipticity at 220 nm, and enzyme activity. From the following arguments, we found that the process deviates from a two-state model and intermediates are significantly populated even at equilibrium: (1) the noncoincidence of the transition curves and (2) the asymmetry of the transition curve obtained from CD measurements. From these differ...
Effect of feeding on the fate of orally administered phenylbutazone, trimethoprim and sulphadiazine in the horse. Phenylbutazone, sulphadiazine and trimethoprim were administered to three horses on two occasions, recently fed and unfed, and the effect of feeding on the pharmacokinetics of the three drugs assessed. The mean peak concentrations of phenylbutazone and trimethoprim were reduced by feeding by 34 and 75 per cent, respectively. The pharmacokinetics of sulphadiazine were not significantly affected.
The starch digestion test in the horse. Variable results were obtained when the starch digestion test was carried out on a suspected case of malassimilation in a horse. In order to re-evaluate this test, 15 starch digestion tests were carried out using 4 horses. Results showed a marked variation in the increase in plasma glucose levels between individual horses and especially between poor and good condition horses when the dose of starch was based on body mass. Results also suggest that a fixed dose of starch may give more consistent results.
Drug disposition in the neonatal animal, with particular reference to the foal. Differences between neonatal and adult animals in their response to drugs can usually be attributed to altered disposition (ie, distribution, metabolism and excretion) processes during the neonatal period. These alterations affect the plasma concentrations as well as the concentrations of drug attained at the receptor site. Some characteristics of the neonatal period include greater absorption from the gastrointestinal tract, lower extent of plasma protein binding, increased apparent volume of distribution of drugs that distribute in extracellular fluid or total body water, increased permeabil...
Diurnal changes in the metabolic indices in the blood of racing Arabian horses. In 8 stallions and 6 mares of pure Arabian breed the diurnal changes in the levels of lactic and pyruvic acid, glucose, and alkaline reserve were studied. All of them showed distinct diurnal changes but they failed to fulfil the criteria of circadian rhythm according to Halberg. It was found that all peaks occurred during the dark phase of the 24 h period except the glucose level in the stallions. Three of the indices studied showed higher mean diurnal levels in the mares than in the stallions. Only in the glucose level the mean values were reversed.
Effects of physical activity and other types of stress on catecholamine metabolism in various animal species. The investigation of catecholamine (CA) metabolism in animals subjected to various types of stress (different pain syndromes; cranial trauma; immobilization; cooling) and physical exercise shows considerable similarity among species in the sequence of changes, leading from the activation to the depletion of the sympathoadrenal system. The changes caused by physical exercise tend to be more pronounced in individuals with a genetic predisposition to greater stress responses. Stress adaption, induced by special training or by long-duration exposure to hypoxia, can substantially prevent the change...
[Various aspects of lactate production and disappearance in trotters during exertion]. Venous lactate concentrations were determined in standard-bred trotters following exercise of varying intensity to obtain a useful parameter in determining the working capacity of horses. After standard exercise, well-trained horses produced less lactate than did inadequately trained horses. During the post-exercise resting period, lactate disappeared faster from the blood in well-trained horses and young lightly trained horses than it did in poorly trained horses. Steady-state training resulted in lower lactate levels than those recorded after racing, whereas interval training resulted in the...
Effect of age on anion gap in clinically normal Quarter Horses. Anion gap [AG = (Na + K) - (Cl + HCO3)] was determined in Quarter Horses: 10 clinically normal foals 0.5 to 3 days, 2 to 3 weeks, and 5 to 7 weeks of age; 10 yearlings; and ten 2-year-olds. Mean AG (+/- 1 SD) were 12.8 +/- 3.3, 15.2 +/- 2.9, 14.0 +/- 1.6, 12.3 +/- 1.8, and 10.4 +/- 1.2 mEq/L, respectively. The 4 to 5 mEq/L higher AG in 2- to 7-week-old foals, when compared with that in 2-year-old horses, can be explained in part by hyperphosphatemia (2 mEq/L) and lower calcium values (0.4 mEq/L). Decreased globulin concentrations may also contribute to the higher AG. The AG can be useful in th...
Effects of training on cardiorespiratory function in the horse. The effects of 5- and 10-wk treadmill exercise training on cardiorespiratory function were evaluated in the horse. Cardiac output (Q), heart rate (HR), and stroke volume (SV), as well as left ventricular (LVP), aortic (AoP), and mean right atrial (RAP) pressures and the peak first time derivative of LVP (LV dP/dtmax), were measured at rest and at five different levels of exercise up to 90% of initial predicted maximal HR (HRmax). Oxygen uptake (VO2) and respiratory exchange ratio (R) were also obtained under the same conditions. At rest, although HR was no different after training, LV dP/dtmax...
Insulin tolerance in laminitic ponies. Sensitivity to insulin was assessed in ponies episodically affected with chronic laminitis by measurement of blood glucose and arterial blood pressure during insulin tolerance tests. In terms of blood glucose values, laminitic ponies were significantly less sensitive to insulin than controls. Conversely, a post-insulin decline in diastolic, systolic and mean blood pressure values was significantly greater in laminitic ponies than in controls.
