Omneity® Pellets
All-In-One Vitamin & Mineral Pellet
Topic:Metabolism
Equine metabolism encompasses the biochemical processes that occur within horses to maintain life, including the conversion of food into energy, the synthesis of necessary compounds, and the elimination of waste products. These processes are essential for supporting various physiological functions such as growth, reproduction, and physical performance. Key components of equine metabolism include carbohydrate, fat, and protein metabolism, each of which contributes to the overall energy balance and health of the horse. Factors influencing metabolic rate and efficiency in horses include age, breed, diet, exercise, and health status. This page compiles peer-reviewed research studies and scholarly articles that explore the mechanisms, regulation, and implications of metabolic processes in equine physiology.
Effect of growth and training on muscle adaptation in Thoroughbred horses. To determine the effect of growth and training on metabolic properties in muscle fibers of the gluteus medius muscle in adolescent Thoroughbred horses. Methods: Twenty 2-year-old Thoroughbreds. Methods: Horses were randomly assigned to 2 groups. Horses in the training group were trained for 16 weeks, and control horses were kept on pasture without training. Samples were obtained by use of a needle-biopsy technique from the middle gluteus muscle of each horse before and after the training period. Composition and oxidative enzyme (succinic dehydrogenase [SDHI) activity of each fiber type were de...
Pharmacokinetics of gentamicin C1, C1a and C2 in horses after single intravenous dose. Gentamicin pharmacokinetics has not been studied in horses. Pharmacokinetics of gentamicin C1, C1a and C2 components following i.v. administration of total gentamicin at 6.6 mg/kg bwt to 6 healthy mature horses was determined. Significant differences in clearance, half-life (t 1/2), and mean residence time (MRT) between the gentamicin Cia and the 2 other components were found. The total body clearance (CL) of gentamicin C1a was 1.62 +/- 0.50 ml/min x kg and similar to the glomerular filtration rate (GFR) reported for horses. The CL of gentamicin C1 and C2 were 1.03 +/- 0.08 ml/min x kg and 1.1...
Endothelin response during and after exercise in horses. The objective of the present study was to measure plasma endothelin-1 (ET-1) at rest and during exercise in the horse. Six healthy, Standardbred and Thoroughbred mares (5.3+/-0.8 years; 445.2+/-13.1 kg) which were unfit, but otherwise accustomed to running on the treadmill, were used in the study. Plasma ET-1 concentrations were measured using a commercially available radioimmunoassay kit. Horses performed three trials: a standing control (CON) trial where blood was collected from the jugular vein every minute for 5 min; a graded exercise test (GXT) where blood samples were collected at the en...
Use of infrared thermography to detect injections and palmar digital neurectomy in horses. Thermography is a non-contact, non-invasive technique that detects surface heat emitted as infrared radiation. Because skin temperature reflects the status of underlying tissue metabolism and blood circulation, abnormal thermal patterns can signify areas of superficial inflammation. The objective of this study was to determine if thermography could detect the injection of analgesic and neurolytic agents and surgical palmar digital neurectomy. Procedures evaluated include injection of the lumbar region, suspensory ligaments, tibial nerve, palmar digital nerves, and palmar digital neurectomy. Th...
Monocarboxylate transporters and lactate metabolism in equine athletes: a review. Lactate is known as the end product of anaerobic glycolysis, a pathway that is of key importance during high intensity exercise. Instead of being a waste product lactate is now regarded as a valuable substrate that significantly contributes to the energy production of heart, non-contracting muscles and even brain. The recent cloning of monocarboxylate transporters, a conserved protein family that transports lactate through biological membranes, has given a new insight into the role of lactate in whole body metabolism. This paper reviews current literature on lactate and monocarboxylate transpo...
Serum concentrations of keratan sulfate, osteocalcin, and pyridinoline crosslinks after oral administration of glucosamine to standardbred horses during race training. To determine the effects of orally administered glucosamine on concentrations of markers of bone and cartilage metabolism in Standardbred horses during race training. Methods: Twenty 16- to 20-month-old Standardbreds beginning race training. Methods: Horses were randomly assigned to 2 groups. One group received glucosamine hydrochloride (4 g, PO, q 12 h), and the second (control) group received glucose (4 g, PO, q 12 h). Serum samples were obtained prior to onset of the study (baseline) and at regular intervals for 48 weeks for determination of concentrations of keratan sulfate (KS), osteocalc...
Nitric oxide synthase inhibition speeds oxygen uptake kinetics in horses during moderate domain running. Within the moderate exercise intensity domain, the speed of oxygen uptake (V(O(2))) kinetics at the transition to a higher metabolic rate is thought to be limited by an inertia of the oxidative machinery. Nitric oxide (NO)-induced inhibition of O(2) consumption within the electron transport chain may contribute to this inertia. This investigation tested the hypothesis that a reduction or removal of any such NO effect via infusion of N(omega)-nitro-L-arginine methyl ester (L-NAME; a NOS inhibitor) would speed V(O(2)) kinetics at the onset of moderate exercise. Five Thoroughbred geldings underwe...
ATPase and Adpase activities in synovial membrane of equine metacarpophalangeal joint. ATPase and ADPase activities capable of hydrolyzing nucleoside di- and triphosphates in the presence of Ca2+ are present in synovial membrane of metacarpophalangeal joint mainly associated to membrane fractions. These hydrolytic activities have been considered involved in the inflammatory process where ATP and ADP are inflammatory mediators while adenosine counteracts this effect. Both, subcellular localization and kinetic properties of these nucleotidase activities, suggest that could correspond to single enzyme called ATP-diphosphohydrolase or apyrase. The comparison of the activity on ATP-C...
Effect of extraction time and acid concentration on the separation of proglycogen and macroglycogen in horse muscle samples. The objective of this study was to determine whether the concentrations of proglycogen (PG) and macroglycogen (MG) in biopsy samples of horse muscle are influenced by extraction time or perchloric acid (PCA) concentration. In study 1, individual muscle-biopsy samples from 10 horses were divided into 4 parts each and then randomly subjected to 4 periods of extraction (10, 20, 60, or 120 min) with 1.5 M PCA. In study 2, individual muscle-biopsy samples from 6 horses were divided into 24 pieces each and then randomly subjected to 12 combinations of extraction time (10, 20, 30, or 40 min) and PCA ...
Effects of dietary flaxseed oil supplementation on equine plasma fatty acid concentrations and whole blood platelet aggregation. An 18-week feeding trial was performed to investigate the effects of an omega-3 (n-3) fatty acid-enriched ration on plasma fatty acid concentrations and platelet aggregation in healthy horses. Flaxseed oil served as the source of the n-3 fatty acid alpha-linolenic acid (ALA). Twelve horses were fed dietary maintenance requirements using a complete pelleted ration (80%) and timothy grass hay (20%) for a 2-week acclimation period before being randomly assigned either to a treatment (group 1) or control (group 2) group. Group 2 horses (n = 6) were fed the diet described in the acclimation period,...
Analysis of the variations of follicular fluid composition during follicular growth and maturation in the mare using proton nuclear magnetic resonance (1H NMR). Follicular development and ovulatory processes in mammals involve local biochemical changes as a result of substantial modifications in cellular metabolism, the most well known of which is steroid variation. In the present study, the intrafollicular variation of several other components was studied using proton nuclear magnetic resonance ((1)H NMR). This approach made it possible to demonstrate that the intrafollicular biochemical content changes during follicular growth and maturation. Follicular fluid was aspirated by ovarian puncture of the dominant follicle at various physiological stages ...
Effect of withholding feed on concentration and composition of plasma very low density lipoprotein and serum nonesterified fatty acids in horses. To measure and compare the concentration and composition of very low-density lipoprotein (VLDL) in plasma and selected lipids in serum of horses fed mixed grass hay ad libitum or denied feed for 36 hours. Methods: 4 healthy adult mares. Methods: Mares were either fed mixed grass hay ad libitum or denied feed for 36 hours beginning at 8:00 AM. Blood samples were collected every 2 hours during the study period and analyzed for nonesterified fatty acid (NEFA), triglyceride (TG), VLDL, and glucose concentrations and composition of VLDL. Results: Withholding feed significantly increased mean serum ...
Molecular characterisation of carbohydrate digestion and absorption in equine small intestine. Dietary carbohydrates, when digested and absorbed in the small intestine of the horse, provide a substantial fraction of metabolisable energy. However, if levels in diets exceed the capacity of the equine small intestine to digest and absorb them, they reach the hindgut, cause alterations in microbial populations and the metabolite products and predispose the horse to gastrointestinal diseases. We set out to determine, at the molecular level, the mechanisms, properties and the site of expression of carbohydrate digestive and absorptive functions of the equine small intestinal brush-border memb...
Parenteral nutrition for horses with gastrointestinal disease: a retrospective study of 79 cases. Parenteral nutrition is advocated for sick foals and horses, although there is no report which has critically evaluated its benefits in this species. Therefore, the hypothesis that parenteral nutrition (PN) is beneficial for horses with severe gastrointestinal disease was investigated in a retrospective study. Records from 79 treatment courses in horses with gastrointestinal disease were reviewed for the years 1992-2000. The fatality rate (48.1%) was attributed to the severity of the primary disease. Complications due to PN were recorded and hyperglycaemia was the most common complication asso...
Dietary soyabean oil depresses the apparent digestibility of fibre in trotters when substituted for an iso-energetic amount of corn starch or glucose. The aim of the present study was to establish whether the inhibitory effect of fat feeding on fibre digestion has been underestimated due to the substitution of fat for corn starch. A high fat intake has been shown to lower total intestinal tract apparent digestibility of crude fibre in horses but, since fat was substituted for nonstructural carbohydrates, including starch, the specific effect of fat could not be ascertained. The possibility could not be excluded that starch also inhibits fibre digestibility, so that the fat effect observed earlier would have been underestimated. In this study...
Prednisone per os is likely to have limited efficacy in horses. Based on its efficacy for the treatment of human asthma, the corticosteroid prednisone is commonly used in horses for treatment of recurrent airway obstruction. However, recent studies have failed to show any benefit of prednisone tablets for the treatment of this condition. The purpose of this study was to determine why oral prednisone has poor efficacy for the treatment of heaves in horses. In a crossover study, 5 horses were given the following treatments: prednisone tablets, prednisone liquid, prednisolone tablets, prednisolone liquid and i.v. prednisolone sodium succinate (positive contro...
Cytosolic ratio of malate dehyrogenase/lactate dehydrogenase activity in peripheral leukocytes of race horses with training. The activities of the enzymes involved in the malate-aspartate shuttle and m RNA expression of malate dehydrogenase (MDH), a crucial enzyme for the NADH shuttle that produces ATP in glucose metabolism in the peripheral leukocytes of horses, were measured to investigate the change in metabolic states with training. There were no significant differences in plasma glucose and immunoreactive insulin concentrations between race horses and riding horses, used as a comparable reference. The cytosolic and mitochondrial MDH activities in leukocytes of race horses were significantly higher than those of...
The concentration of plasma triacylglycerols in horses fed diets containing either medium chain triacylglycerols or an isoenergetic amount of starch or cellulose. In a Latin square design, six horses were fed hay and concentrates with isoenergetic amounts of either starch, cellulose or medium chain triacylglycerols (MCT). The dietary variables provided on average 22% of total dietary net energy. Plasma triacylglycerols and other variables of lipid metabolism were determined. The experimental periods lasted 21 days. Blood samples were taken just before the morning meal and three and six hours later. The diet rich in MCT significantly raised the plasma level of triacylglycerols when compared to either the starch- or cellulose-rich diet. The plasma concent...
Serum keratan sulphate as a cartilage metabolic marker in horses: the effect of exercise. Keratan sulphate (KS) concentration in sera from resting horses and horses training daily on a racetrack was measured by an inhibition enzyme-linked immunosorbent assay (ELISA) using anti-equine KS antibody 1/14/16H9. For the in-training horses, serum KS concentrations in 2-year-old-horses was significantly higher than 3- or 4-year-old-horses. A higher concentration of serum KS was found in the in-training group than in the long-term resting group in 2-year-old-horses. Serum KS concentration increased remarkably immediately after training in healthy horses, and at 1, 5, 9 and 24 h after traini...
Effect of holding at room temperature on initial chromatin configuration and in vitro maturation rate of equine oocytes. The relationship of holding time in media at room temperature (approximately 22 degrees C) to initial chromatin configuration and rate of in vitro maturation (IVM) of equine oocytes was determined. Only oocytes having a complete, compact cumulus were used in this study. Oocytes were removed from ovaries 3.5-8 h after slaughter and were put into one of four treatment groups: (1) immediate/fix (IF) = immediate fixation following removal from the ovary; (2) delay/fix (DF) = fixation after oocytes were held 1-4 h in medium at room temperature; (3) immediate/mature (IM) = immediate placement into m...
The isomeric metabolites of doxepin in equine serum and urine. Due to its tranquilizing properties, the tricyclic antidepressant doxepin may be misused as a doping agent in competition horses. Therefore, efficient analytical procedures are required to detect this drug in samples submitted for doping control. To screen for parent doxepin in equine blood and urine, a less specific method has been accepted employing gas chromatography (GC) combined with electron impact (EI) mass spectrometry (MS). The aim of this study was identification of doxepin metabolites providing more specific MS data to verify positives resulting from screening. Thus, after a horse w...
Effect of 2-deoxy-D-glucose on gonadotropins, prolactin and serum glucose concentrations in the mare. In a variety of species, glucoprivation results in the suppression of the reproductive axis. Two experiments were performed to test the hypothesis that blockade of glucose metabolism via administration of the glucose inhibitor 2-deoxy-D-glucose (2DG) to mares would cause a modification in gonadotropin and prolactin secretion. Long-term ovariectomized mares (Experiment 1, n=4) or ovary-intact mares during the follicular phase of a synchronized estrous cycle (Experiment 2, n=4 per dose) were treated with 2DG. The dose of 2DG used in Experiment 1 was 100mg 2DG/kg BW, but because severe behavioral...
