Omneity® Pellets
All-In-One Vitamin & Mineral Pellet
Topic:Glucose
Glucose is a simple sugar that serves as a primary energy source for horses. It is metabolized through various biochemical pathways to support cellular functions and overall energy requirements. In equine physiology, glucose levels are influenced by factors such as diet, exercise, and metabolic health. Monitoring glucose concentrations is important for understanding metabolic conditions, such as insulin resistance and equine metabolic syndrome, which can affect a horse's health and performance. This page compiles peer-reviewed research studies and scholarly articles that explore the regulation, metabolism, and clinical implications of glucose in equine health.
Effects of phenylbutazone on glucose tolerance and on secretion of insulin in healthy geldings. The effect of phenylbutazone (4.4 mg/kg of body weight, IV, q 24 h, for 5 days) on glucose tolerance and on secretion of insulin in 6 healthy geldings was determined. Phenylbutazone significantly lowered fasting concentrations of glucose in plasma but did not significantly change the concentration of insulin in serum. There was no significant effect of phenylbutazone on glucose tolerance, on secretion of insulin, or on the area under the insulin/glucose ratio vs time curve in healthy geldings, as determined by paired t test analysis.
Blood chemistry and skeletal muscle metabolic responses during and after different speeds and durations of trotting. Eight standardbred horses trotted on a treadmill for 55 mins at a sub-maximal speed of 5m/sec and subsequently performed an exercise test consisting of 2 min intervals at increasing speed. Heart (HR) and respiratory (Rf) rates and venous blood samples were obtained before, during and for 5 mins after exercise. Gluteus medius muscle biopsies and rectal temperatures were taken before and after exercise. The mean HR was 132/min and the mean Rf was 156/min during the 5m/sec trotting. With 5m/sec exercise, plasma free fatty acids (FFA), glucose, creatinine and cortisol concentrations increased mark...
Echinococcus granulosus: a comparison of free amino acid concentration in hydatid fluid from primary and secondary cysts and host plasma. A total of 28 components were detected in the free amino acid (FAA) pool of hydatid fluid from primary and secondary equine cysts, secondary ovine cysts and host plasma. Examination of data from equine cysts revealed that the majority of FAAs were present in significantly greater concentrations in secondary cysts, glycine being over 30 times more concentrated. Values for total carbohydrates and glucose did not, however, differ significantly and total protein content was greater in primary cysts. Comparison of the (FAA) pool of secondary equine and ovine cysts revealed strain variation. It was ...
A study of diurnal changes in cortisol and glucose levels and FDPA activity in foals during the first 13 weeks of life and in their lactating mothers. 1. In six standard-bred mares and their foals diurnal changes in the cortisol and glucose levels and in FDPA activity were studies for 13 weeks of foal life. 2. In the cortisol level diurnal rhythm was found in the 3rd, 7th and 11th week of foal life and in the 11th week of lactation in mares. 3. In mares the mean diurnal cortisol level changed from 32 ng/ml in the first week to 57 in the 11th week and in foals from 24 in the first week to 16 ng/ml in the 11th week. 4. In the glucose level no diurnal rhythm was observed. 5. In mares the mean diurnal glucose level after parturition was about 58...
[Performance testing of mules and Haflinger horses used as pack animals]. During 20 weeks blood constituents in peripheral blood (Erythrocyte count, Packed cell volume, Hemoglobin, Sedimentation rate, activities of Aspartate aminotransferase, Alanine aminotransferase, Creatine phosphokinase, Lactate dehydrogenase, Lactate dehydrogenase-1-isoenzyme, Glucose, Lactate, Total bilirubin), pulse and respiration rate were determined at rest and after exercise. Significant increase of blood values after exercise could be noted in relation to the intensity of exercise and the performance of the animals. The well trained horses had an increase of their performance according t...
Metabolism of naturally occurring [13C]glucose given orally to horses. In 5 horses, 13CO2/12CO2 ratios in expired air were determined using isotope mass spectroscopy to investigate metabolism of naturally occurring [13C]glucose. Oral glucose tolerance tests (OGTT) were performed using maize or beet glucose. Maize has a higher 13C concentration than that of most plants. The 13CO2/12CO2 ratios after OGTT was performed using maize glucose were compared with 13CO2/12CO2 ratios in expired air after OGTT was performed using beet glucose. The ratio also was determined during the period horses were not fed. Using OGTT, all horses were glucose tolerant. The OGTT performed...
Dietary requirements and athletic performance of horses. There is no clear evidence that the chronic requirement for any non-energy yielding nutrient rises in proportion as the energy requirement increases with hard work. The need for protein, and probably that for calcium, remain a function of bodyweight daily. Some proportionality with energy may exist for certain nutrients, although the evidence has not been adduced. For example, because of an increase in both the proportion and amount of propionic acid in the volatile fatty acids of caecal contents, the tissue requirement for vitamin B12 may rise with an increase in the rate of energy metabolism...
Progressive myotonia in foals resembling human dystrophia myotonica. A severe and progressive neuromuscular disorder accompanied by clinical, electrophysiological, and pathological features resembling human dystrophia myotonica was observed in three foals. This disorder was apparent as early as 1 month of age and involved progressive skeletal muscle dysfunction, initially characterized by proximal muscle hypertrophy and hypertonicity with subsequent muscle stiffness, weakness, and atrophy. Multisystem involvement was manifested in one case by testicular hypoplasia, early cataract formation, and borderline glucose intolerance. Prolonged dimpling of these large r...
Adrenocorticotropin-containing neoplastic cells in a pars intermedia adenoma in a horse. Pituitary-dependent hyperadrenocorticism was diagnosed in a 14-year-old Arabian mare with chronic weight loss, hirsutism, polyuria, and polydipsia. The mare had a stress leukogram, glucosuria, and consistent hyperglycemia. Plasma glucose concentrations were resistant to suppression by insulin. Plasma cortisol concentrations were within normal limits, but did not respond to dexamethasone suppression and had an exaggerated response to ACTH stimulation. At necropsy, a chromophobe adenoma of the pars intermedia of the pituitary gland was found. The zona fasciculata of the adrenal cortex and the pa...
Responses of blood glucose, insulin and cortisol concentrations to common equine diets. Two experiments were conducted to determine the response of blood glucose, insulin and cortisol levels to four common equine diets. Experiment 1 was designed to determine the diurnal variation of glucose and two glucoregulatory hormones, insulin and cortisol, in four fasting geldings. No diurnal variation was observed in either glucose or insulin levels during the 24-h sampling period. However, cortisol levels did exhibit a circadian rhythm, with elevated values observed in the morning and low values in the evening. Experiment 2 investigated the response of glucose, insulin, cortisol and selec...
Neuroendocrine changes produced by competition stress on the Thoroughbred race horse. 1. Packed cell volume (PCV) and plasma catecholamines, cortisol and glucose were determined in blood samples obtained from race horses, after competition. 2. All these parameters were higher than basals but catecholamines increased 6-7 times while cortisol was enhanced only by 25%. 3. The increase of glucose and PCV was related to the rise of catecholamines. 4. In samples withdrawn after overnight stress caused by change of horseshoes, it was not possible to find values from basal values significantly different. 5. Influence of nervous temperament was observed only in the higher hematocrit fou...
Glucose metabolism in a pony mare with a tumour of the pituitary gland pars intermedia. A case of pituitary dependent hyperadrenocorticism in a horse is reported. Clinical signs included hirsutism, polydipsia and general debility. The horse was persistently hyperglycaemic and glucose values were unchanged following subcutaneous administration of insulin. Resting cortisol values were normal, but dexamethasone suppression of cortisol concentration was shorter than normal. Plasma glucose, cortisol, insulin and glucagon concentrations were measured as part of an intravenous glucose tolerance test. The patient responses were different from those in a control pony.
Metabolic responses to exercise in the racehorse: changes in plasma alanine concentration. Previous studies in humans have shown that alanine is released from the skeletal muscle in proportion to the work load. We have measured plasma alanine and urea concentrations in well-trained Standardbred and Finnish-bred (cold-blooded) trotters after a graded-intensity exercise and during recovery to study metabolic responses to exercise in this animal model. As controls we measured blood lactate, pyruvate, and glucose concentrations as well as hematocrit values. Metabolic responses to exercise were closely reflected in all these parameters. Plasma alanine increased relatively more than plasm...
Some metabolic and hormonal changes associated with general anaesthesia and surgery in the horse. Three different anaesthetic techniques were studied in normal, healthy Thoroughbred or Thoroughbred type horses. These were (a) acepromazine, thiopentone and suxamethonium; (b) acepromazine, glyceryl guaiacolate and a 'half-dose' of thiopentone; and (c) xylazine and ketamine. Anaesthesia was maintained with halothane vaporized in oxygen and nitrous oxide. All horses underwent either laryngeal or body surface surgery. Heart rate, packed cell volume, blood glucose and lactate, plasma non-esterified fatty acids, insulin and cortisol were measured before, during and after surgery. The greatest met...
Metabolic and hormonal responses to neuroleptanalgesia (etorphine and acepromazine) in the horse. Administration of etorphine and acepromazine to horses was associated with an increase in haematocrit, blood glucose, blood lactate and plasma non-esterified fatty acids (NEFA). The rise in plasma NEFA was most striking following injection of the antagonist diprenorphine and could contribute to the production of cardiac arrhythmias. Plasma insulin was depressed at the end of surgery. These changes, plus profuse sweating, are indirect evidence of strong sympathetic stimulation. Plasma cortisol did not alter significantly due to wide individual variation. Venous blood pH fell, reflecting the ris...
Serum triiodothyronine and thyroxine concentrations in weanling horses fed carbohydrate by direct gastric infusion. Plasma glucose and serum insulin, thyroxine, and triiodothyronine concentrations were monitored in 6 weanling Thoroughbreds after direct gastric infusion of solutions containing sucrose or casein. Neither plasma glucose nor serum hormone concentrations were affected by infusions of water or by infusions of 326 or 424 g of casein/250 kg of body weight. However, glucose and hormone concentrations increased significantly (P less than 0.001) after infusions of 649 or 844 g of sucrose/250 kg. Initial rates of increase were more rapid and increases were subsequently reversed more rapidly when 844 g ...
Effect of yohimbine on xylazine-induced hypoinsulinemia and hyperglycemia in mares. Serum insulin and plasma glucose concentrations were determined in 8 mares. Four IV treatments were studied: xylazine (1.1 mg/kg of body weight); yohimbine (0.125 mg/kg); yohimbine (0.125 mg/kg) followed 5 minutes later by xylazine (1.1 mg/kg); and 5 ml of isotonic saline solution as a control. Blood samples were collected before (time 0) and at 5, 15, 30, 60, 120, and 180 minutes after drug administration. Serum insulin concentration decreased and plasma glucose concentration increased in mares given xylazine. Plasma glucose concentration was unchanged in control mares and in mares given yohi...
Sympathoadrenal and other responses to hypoglycaemia in the young foal. The effects of insulin-induced hypoglycaemia on plasma catecholamines, cortisol and metabolites have been examined in newborn and 7-14-day-old foals. The fall in plasma glucose elicited by the highest dose of insulin (1.0 i.u./kg) given to the neonates was slower in onset and less severe in effect than 0.5 i.u./kg in the older foals. There was a significant inverse correlation between the concentrations of glucose and adrenaline (but not noradrenaline) in plasma once the glucose level had fallen below 2 mmol/l; the adrenergic response to hypoglycaemia was greater in the 7-14-day-old foals than...
An evaluation of an oral glucose-glycine-electrolyte solution for the treatment of experimentally induced dehydration in the horse. Five standardbred geldings were given 1 mg/kg bodyweight of frusemide by intramuscular injection to induce mild dehydration. After food and water deprivation overnight, the mean weight loss was 24.4 +/- 1.8 kg (5.5 per cent of bodyweight). The horses were then given an equivalent volume of an oral glucose-glycine-electrolyte solution by stomach tube. No more than 10 litres was given every 30 minutes until the calculated bodyweight loss had been replaced. Measurements made before, during and after the fluid administration included bodyweight, arterial blood haematocrit, PCO2, pH, standard bicar...
Endocrinologic, hematologic, and heart rate changes in swimming horses. Two identical experiments, using Standardbred and Thoroughbred horses (experiment A, n = 31; experiment B, n = 17) on a swimming regimen, were performed 1 week apart to evaluate short-term heart rate, hematologic, and endocrinologic changes. Horses were placed in 4 categories based on duration of swimming (1 to 5, greater than 5 to 10, greater than 10 to 15, and greater than 15 minutes). Heart rate, PCV, and plasma concentrations of total protein, cortisol triiodothyronine, thyroxine, insulin, and glucose of each horse were evaluated before, immediately after, and 1 hour after swimming. For ex...
Definition of diabetes mellitus. The nomenclature of human diabetes mellitus (DM) has been revised, and this classification has been accepted throughout the medical world and literature. The major categories of diabetes are: insulin-dependent DM, type I or IDDM; noninsulin-dependent DM, type II or NIDDM; secondary DM or type S; impaired glucose tolerance, IGT; gestational diabetes; and previous abnormality of glucose tolerance, PrevAGT. A review of the literature has shown that over half of the documented diabetic dogs, with a single medical diagnosis, appear to be type I, IDDM, with a substantial proportion being type S, and...
Diabetes mellitus associated with bilateral granulosa cell tumors in a mare. Both ovaries in a 10-year-old American Saddle Horse mare were determined to be larger than normal. The mare had problems with infertility during the preceding 3 years. Clinical evaluation revealed that the mare was polyuric, polydypsic, hyperinsulinemic, and hyperglycemic, and had reduced tolerance to exogenous glucose. Bilateral granulosa cell tumors were identified on histologic examination of the ovaries. The precise mechanism for the secondary diabetes mellitus was not determined; however, the cause was suspected to be a result of the synthesis and release of a hormonal substance by the tu...
Glucose tolerance and insulin sensitivity in ponies and Standardbred horses. The existence of an innate insulin insensitivity in ponies was investigated and compared with the situation in larger breeds of horse. Ponies that were fat or had previously suffered laminitis were found to be far more intolerant to oral glucose loading (1 g/kg bodyweight [bwt]) than normal ponies or Standardbreds. These ponies also exhibited a far greater response in plasma insulin levels after glucose loading. Insulin response tests (0.4 iu/kg bwt insulin intravenously) showed only a minimal and very protracted response in both the fat and laminitic groups. The relevance of these findings in...
Effects of xylazine on renal function and plasma glucose in ponies. The intravenous administration of xylazine (1.1 mg/kg bodyweight) in six ponies resulted in a significant increase in urine output over two hours, with maximum flow occurring between 30 and 60 minutes after injection. Urine specific gravity, osmolality and glucose concentration decreased. Renal clearance of endogenous creatinine was unchanged. Significant increases in the excretion of potassium and chloride occurred. Plasma glucose concentration was increased 30 minutes after the administration of xylazine by a mean value of 37 per cent. Serum osmolality and sodium, potassium and chloride conc...
[Normal values of the hematological, biochemical and enzymological indices of the donkey]. Studied were a total of 85 (33 male and 52 female) donkeys of the Martina Franca breed of the domestic ass, aged from one to twelve years. Stated are the results for the normal values of hemoglobin, hematocrit, ESR, total erythrocyte and leukocyte counts, leukocyte formula, blood sugar, cholesterin, urea, total protein and protein fractions, some micro- and macroelements, and enzymes as tabulated in four diagrams. No differences have been established with regard to sex. It has been found that with young animals the normal values of hemoglobin and erythrocytes are lower than with adult ones. Wi...
An apparatus for collecting blood samples by radiotelemetry from horses during exercise. An apparatus was designed to collect four consecutive blood samples from exercising horses. The collection of each sample was controlled by valves activated by radiotelemetry signals transmitted by an observer. Using the device, venous blood samples were collected from ten thoroughbred racehorses before, during and after a 400 m training gallop. Blood glucose increased markedly post-exercise. Both phosphorus and potassium concentrations increased during exercise, decreased post-exercise and recovered to pre-exercise levels within 120 minutes. The system was modified to collect anaerobic sample...
Hormonal responses to exercise and training. Current knowledge and understanding of the hormonal response to exercise are limited, whether in relation to horses, humans, or other species. The changes in plasma concentration of some hormones occur early in exercise, apparently owing to a neuronal stimulation, whereas others, being pituitary dependent, require hormonal stimulation. Also, although it is possible to observe changes in plasma concentrations of hormones, the mechanism by which this is achieved is not always understood, and unless the nonprotein-bound, or active, form of the hormone is also determined, changes in plasma concent...
Comparison of acetate and glucose incorporation into rat and horse skin lipids. The relative efficiency of acetate and glucose as substrates for the biosynthesis of lipids in the skin of the rat and horse was examined using in vivo pulse labelling of skin with [1-14C]acetate and [U-14C]glucose by intradermal injections. The resulting radiolabelled lipids were recovered in the rat by punch biopsy as well as by daily, long-term skin surface lipid collections and in the horse by punch biopsy of the injection sites. The lipids were examined by liquid scintillation and by a combination of thin-layer chromatography and autoradiography. In both species the recovery of radiolabel...
Methods of assigning accurate values to reference serum. Part 2. The use of definitive methods, reference laboratories, transferred values and consensus values. Eight analytes (Ca, Cl, cholesterol, glucose, Mg, K, Na and urate) have been determined in one horse serum masterlot by up to six different procedures: (i) by so-called definitive methods; (ii) by a group of reference laboratories using a variety of analytical methods; (iii) using the results of two independent external quality assessment schemes; (iv) by transferring values from a human serum standard reference material analysed by definitive methods; (v) by similar transfer of values from several batches of horse reference serum previously analysed by definitive methods; and (vi) as in (v) b...
