Sodium is an essential electrolyte in horses, involved in maintaining fluid balance, nerve function, and muscle contraction. It plays a significant role in the regulation of osmotic pressure within cells and the overall homeostasis of bodily fluids. Horses obtain sodium primarily through their diet, and it can be supplemented through salt blocks or electrolyte solutions, especially in cases of heavy sweating or increased physical activity. Imbalances in sodium levels, either deficiency or excess, can impact a horse's health and performance. This page compiles peer-reviewed research studies and scholarly articles that explore the metabolism, dietary requirements, and physiological effects of sodium in equine health.
Lloyd DR, Evans DL, Hodgson DR, Suann CJ, Rose RJ.We examined the effects of sodium bicarbonate in 6 Thoroughbred horses during submaximal and maximal treadmill exercise. Cardiorespiratory function was assessed together with the effect on exercise capacity by determining the run time to fatigue at maximal intensities. To discriminate between sodium bicarbonate's alkalinising effects and the fluid shifts that could result from the high osmotic load, we administered an equimolar solution of sodium chloride as a control. The horses were given sodium bicarbonate (1 g/kg bwt) or an equivalent number of moles of sodium chloride by nasogastric tube....
Cohen ND, Roussel AJ, Lumsden JH, Cohen AC, Grift E, Lewis C.Alterations of acid-base status, and fluid and electrolyte balance subsequent to exercise in Thoroughbred racehorses in North America have not been well-characterized. Des-cribed here are the results of an observational study conducted to characterize changes in fluid and electrolytes following strenuous exercise of 16 Thoroughbreds under routine training conditions. Changes following strenuous exercise were determined for the following variables: serum concentrations of sodium (Na), potassium (K), chloride (Cl) and protein; pH of blood; osmolality of plasma and urine; body weight; and, fracti...
Salloum RM, Duckworth D, Madison JB, Souba WW.The sodium-dependent transporter system responsible for L-glutamine uptake by brush border membrane vesicles prepared from equine jejunum was characterized. Vesicle purity was ascertained by a 14- to 17-fold increase in activity of the brush border enzyme markers. Glutamine uptake was found to occur into an osmotically active space with negligible membrane binding. The sodium-dependent velocity represented approximately 80% of total uptake and demonstrated overshoots. Kinetic studies of sodium-dependent glutamine transport at concentrations between 5 microM and 5 mM revealed a single saturable...
Rudolph JA, Spier SJ, Byrns G, Rojas CV, Bernoco D, Hoffman EP.We recently reported on a linkage study within a Quarter Horse lineage segregating hyperkalaemic periodic paralysis (HYPP), an autosomal dominant condition showing potassium-induced attacks of skeletal muscle paralysis. HYPP co-segregated with the equine adult skeletal muscle sodium channel alpha subunit gene, the same gene that causes human HYPP. We now describe the Phe to Leu mutation in transmembrane domain IVS3 which courses the horse disease. This represents the first application of molecular genetics to an important horse disease, and the data will provide an opportunity for control or e...
Bertone JJ, Shoemaker KE.Blood constituents and vascular volume indices were determined in 5 standing horses by use of 2-period crossover experimental design. Horses were either administered hypertonic (2,400 mosm/kg of body weight, i.v.) or isotonic (300 mosm/kg, i.v.) saline solution. Each solution was administered at a dosage of 5 ml/kg (infusion rate, 80 ml/min). Samples for determination of PCV, plasma volume, blood volume, plasma osmolality, total amount of plasma protein and plasma concentrations of protein, Na, K, and Cl were collected at 0 hour (baseline, before fluid infusion) and 0.5 hour (at the end of flu...
Weiss DJ, Geor R, Smith CM, McClay CB.Echinocytes have been incriminated in the pathogenesis of exertional diseases in horses. To evaluate the hypothesis that echinocytes are dehydrated erythrocytes, we decreased blood sodium and potassium concentrations in 4 horses by administering furosemide (1.0 mg/kg of body weight, q 12 h) for 2 days and we monitored CBC, serum and erythrocyte sodium and potassium concentrations, and echinocyte numbers. Serum sodium concentration decreased progressively over the 48 hours of furosemide administration, then returned to near baseline concentration at 168 hours. A statistically significant decrea...
Freeman DE, Ferrante PL, Palmer JE.A Latin square design was used to compare the effects of laxatives and a corresponding volume of water on gastrointestinal tract function in 4 healthy horses. Horses were intragastrically infused with each of the following: dioctyl sodium sulfosuccinate (DSS; 50 mg/kg of body weight); magnesium sulfate (0.5 g/kg--low dosage); magnesium sulfate (1.0 g/kg--high dosage); and an equal volume of water (6 L) given as a control infusion. From 5 to 33 hours after the high dosage of magnesium sulfate, feces were slightly softer than usual in all horses. In 1 horse, DSS caused mild colic, hyperpnea, and...
Traub-Dargatz JL, Ingram JT, Stashak TS, Kiper ML, Tarr S, Child G, MacAllister CG.Four Quarter Horse foals ranging in age from 6 days to 2 months were determined to have upper airway stridor secondary to polymyopathy suspected to be hyperkalemic periodic paralysis. Electromyography revealed spontaneous muscle activity in all muscles examined. Electromyographic findings were similar in the dams of 3 foals (No. 1, 3 and 4). Hyperkalemia was found in foals 1 and 4. Endoscopically, the upper airway stridor in foals 1 and 3 was confirmed to be attributable to laryngeal and pharyngeal collapse or spasm. Foals 1, 2, and 3 were treated with acetazolamide. Foal 4 was not treated, at...
Gustafson SB, Trotter GW, Norrdin RW, Wrigley RH, Lamar C.Three doses of sodium monoiodoacetate (MIA) were used to induce degenerative changes in articular cartilage in middle carpal joints of horses. Twelve young (2- to 5-year-old) horses, free of lameness, were randomly allotted to 3 groups. One middle carpal joint of each horse was injected with 0.9% NaCl solution (control joint). The contralateral middle carpal joint was injected with 0.09 mg of MIA/kg of body weight (group 1); 0.12 mg/kg (group 2); or 0.16 mg/kg (group 3). After MIA administration, horses were allowed ad libitum exercise in a 2-acre paddock for 12 weeks. At the end of the study,...
Clarke LL, Roberts MC, Grubb BR, Argenzio RA.In ponies fed concentrated (pelleted) meals, postprandial increases of plasma aldosterone have been temporally associated with a decrease in colonic fluid volume that parallels the conclusion of postfeeding fermentation. To determine the significance of short-term increases of plasma aldosterone on the rate of colonic Na absorption, in vitro transport studies were conducted on the mucosae of three morphologically distinct colonic segments (i.e., ventral, dorsal, and small colons) from ponies infused with a high physiological concentration of aldosterone for an 8-h period. In control ponies, ba...
Morley PS, Desnoyers M.A 3-day-old Quarter Horse colt was examined because of signs of severe depression, discomfort, and abdominal straining. The foal seemed disoriented, and the abdomen was tense and distended ventrally. The differential diagnoses included ruptured urinary bladder, retained meconium, septicemia/bacteremia, and neonatal maladjustment syndrome. Serum biochemical analysis revealed marked hyponatremia, hypochloremia, and moderate hyperkalemia, as well as mildly high urea, creatinine, and phosphorus concentrations. The primary differential diagnosis at this time was ruptured urinary bladder. Abdominoce...
Sarasola P, Horspool LJ, McKellar QA.The effect of urine pH on plasma disposition of ampicillin sodium was evaluated. A single dose of 10 mg/kg of body weight was administered IV to Thoroughbreds with alkaline (pH greater than 8.0) or acidic (pH less than 4.5) urine. Urine alkalinity was achieved and maintained by oral administration of up to 400 mg of sodium bicarbonate/kg/d, and acidity was achieved and maintained by oral administration of up to 400 mg of ammonium chloride/kg/d. Ampicillin sodium was measured in the plasma of horses by use of an agar diffusion microbiological assay with Bacillus subtilis as the test organism. T...
Rikihisa Y, Johnson GC, Wang YZ, Reed SM, Fertel R, Cooke HJ.Ehrlichia risticii, an obligate intracellular bacterium in the family Rickettsiaceae, causes Potomac horse fever which is often associated with severe watery diarrhoea. The mechanism of the diarrhoea is unknown. The aim of this study was to determine whether sodium and chloride transport, morphology and cyclic adenosine 3', 5'-monophosphate (cyclic AMP) content of colonic mucosa was altered in E risticii-infected horses. Mucosa-submucosa sheets from the large and small colon of nine infected and seven to nine uninfected horses were set up in Ussing chambers for measurement of short-circuit cur...
Lakritz J, Madigan J, Carlson GP.Hypovolemic hyponatremia attributable to severe fluid and electrolyte alterations was diagnosed in a foal with diarrhea. Subsequent consumption of water resulted in rapid reduction of serum sodium concentration and serum osmolar depression. Clinical signs of neurologic disease developed including blindness, loss of menace response, and seizures. Treatment of this condition with IV administered fluids included hypertonic saline solution (7.2%; 2 ml/kg of body weight), and frequent monitoring of serum electrolyte concentrations and osmolality resulted in gradual correction of the fluid and elect...
Gasthuys F, Messeman C, De Moor A.The influence of hypertonic NaCl 7.2% infusion (4 ml/kg of body weight [BWT]) on plasma (PV) and blood (BV) volumes, sodium (Na), chloride (Cl), potassium (K) plasma concentrations, osmolality (Osm), total protein content (TP), packed cell volume (PCV) and red blood cell count (RBC) was studied in five standing and anaesthetized ponies (standard halothane anaesthesia). Arterial blood gases were followed in the anaesthetized ponies. Isotonic NaCl 0.9% (4 ml/kg of BWT) was used as a placebo in the standing ponies. Isotonic solution in the standing ponies induced few changes: only small decreases...
Ferrante PL, Menninger JH, Spencer PA, Kronfeld DS.Four mares fed a low fiber, high soluble carbohydrate diet were used in a crossover design to evaluate the effects of dietary sodium bicarbonate (NaHCO3) supplementation during daily low-intensity submaximal working conditions. Mares were fed the diet at 1.7 times the maintenance energy requirement for mature horses at work. The horses tolerated the diet well and had no clinical abnormalities. Resting venous blood bicarbonate (HCO3), standard HCO3, and base excess (BE) concentrations significantly (P less than 0.05) increased with NaHCO3 supplementation, but no significant changes in resting v...
Harkins JD, Kamerling SG.There is considerable debate regarding the ergogenic effects of sodium bicarbonate (NaHCO3) on racing performance in horses. Anecdotal evidence suggests that NaHCO3 improves performance by increasing the buffering capacity of the blood and delaying the onset of hydrogen ion-induced fatigue. In a cross-over study, 16 Thoroughbred racehorses were given an aqueous solution of NaHCO3 (0.4 g/kg in 1 litre H2O) or a control treatment (1 litre H2O) before a 1600-m race. Treatments were administered 3 h before the race, which was the time to peak buffering capacity (2.5-3.0 h) determined in a separate...
Waelchli RO, Lutz H, Hermann M, Eggenberger E.Eighteen healthy foals were studied from birth until 2 months of age. Blood samples were obtained at the following times: presuckle, 30 hours, 1, 3, 5, 7 and 9 weeks of age. Changes in serum P, Mg, Ca, Na, K, Cl, iron, AP, ASAT, ALAT, GGT, GLDH, CK, lipase, urea, creatinine, cholesterol, triglyceride, uric acid, protein and fibrinogen and in plasma total solids were examined and the values compared to reference values of adult horses. There were characteristic age related changes in several parameters. Single measurements should be interpreted cautiously to allow for individual variations.
Rudolph JA, Spier SJ, Byrns G, Hoffman EP.A genetic disease observed in certain Quarter horses is hyperkalaemic periodic paralysis (HYPP). This disease causes attacks of paralysis which can be induced by ingestion of potassium. Recent studies have shown that HYPP in humans is due to single base changes within the adult skeletal muscle sodium channel gene. A large Quarter horse pedigree segregating dominant HYPP was studied to determine if mutations of the sodium channel gene are similarly responsible for HYPP in horses. We used cross-species, PCR-mediated, cDNA cloning and sequencing of the horse adult skeletal muscle sodium channel a...
Day TK, Skarda RT.Understanding of the pharmacology of local anesthesia is important for selection of a local anesthetic for use in equine standing surgery. In general, the action potential is inhibited by local anesthetics by preventing the influx of sodium ions across the axonal membrane. The physicochemical properties of each local anesthetic determine the onset of action, potency, and duration of action. Procaine, chlorprocaine, lidocaine, and mepivacaine are the local anesthetics still used clinically in horses; lidocaine is the most widely used. The future of equine local anesthesia may see the introducti...
Houpt KA, Northrup N, Wheatley T, Houpt TR.When a preliminary experiment in sodium-replete ponies revealed an increase, but not a significant increase, in salt consumption after furosemide treatment, the experiment was repeated using sodium-deficient horses in which aldosterone levels might be expected to be elevated to test the hypothesis that a background of aldosterone is necessary for salt appetite. Ten Standardbred mares were injected intravenously with furosemide or an equivalent volume of 0.9% sodium chloride as a control to test the effect of furosemide on their salt appetite and blood constituents. Sodium intake and sodium los...
Tessier GJ, Traynor TR, Kannan MS, O'Grady SM.When the equine tracheal epithelium is mounted in Ussing chambers and bathed in plasma-like Ringer solution, the tissue generates a lumen-negative transepithelial potential (PD) of 22 mV and a short-circuit current (Isc) of 70-200 microA/cm2. Mucosal addition of 10 microM histamine produces a transient increase in the Isc followed by a return to baseline or below. Mucosal addition of 2 microM diphenhydramine inhibits the Isc response to mucosal histamine, whereas 100 microM mucosal cimetidine produces no effect. The average initial increases in Isc over time for mucosal vs. serosal histamine a...
Johnston JK, Freeman DE, Gillette D, Soma LR.Sheets of mucosa from the jejunum of healthy horses were mounted in incubation chambers and bathed with Krebs-Ringer bicarbonate solution. Changes in tissue function and histologic appearance were compared after the following conditions: (1) control conditions for 30 minutes with 95% O2/5% CO2 in the gas phase; (2) same conditions as control, except incubation with superoxide dismutase (300 U/ml) during the last 18 minutes; (3) anoxia for 15 minutes with 95% N2/5% CO2, followed by reoxygenation for 15 minutes; (4) same conditions as 3, except incubation with superoxide dismutase during reoxyge...
Lindner A.Several clinical chemical blood variables were compared, in order to evaluate the differences between Na heparinized plasma and serum samples. Samples from 45 healthy horses were used. No differences between the two sample substrates were found for aspartate aminotransferase, lactate dehydrogenase, lactate dehydrogenase-isoenzymes, creatine kinase, alkaline phosphatase, bilirubin, cholesterol, urea, total protein, alpha-globulin, gamma-globulin, albumin, calcium (Ca), phosphate (P), sodium (Na) and potassium (K). gamma-Glutamyltransferase and beta-globulin were significantly higher in heparini...
Dunlop CI, Hodgson DS, Chapman PL, Grandy JL, Waldron RD.The purpose of this study was to compare the thermodilution technique for estimation of cardiac output with the indocyanine green dye dilution technique at flows between 10 and 39 L/min in halothane-anesthetized horses. The estimation of area of dye dilution cardiac output curves was made by using the fore-'n-aft (FA) triangle method. This shorthand technique was compared with logarithmic exponential extrapolation and summation (extrapolated area), using 64 cardiac output curves. Then, 256 simultaneous thermodilution measurements were compared with dye dilution measurements calculated by use o...
Moon PF, Snyder JR, Haskins SC, Perron PR, Kramer GC.Conventional fluid resuscitation is unsatisfactory in a small percentage of equine emergency surgical cases because the large volumes of fluids required cannot be given rapidly enough to adequately stabilize the horse. In anesthetized horses, the volume expansion and cardiopulmonary effects of a small volume of highly concentrated hypertonic saline-dextran solution were evaluated as an alternative initial fluid choice. Seven halothane-anesthetized, laterally recumbent, spontaneously ventilating, normovolemic horses were treated with a 25% NaCl-24% dextran 70 solution (HSD) at a dosage of 1.0 m...
Johnson PJ, Goetz TE, Foreman JH, Vogel RS, Hoffmann WE, Baker GJ.The effects of whole-body potassium depletion induced by food deprivation on plasma, erythrocyte, and middle gluteal muscle K concentrations was quantified in 16 healthy, adult horses before, during, and at the end of a 7-day period of food deprivation during which water and sodium chloride were available ad libitum. Potassium concentrations were determined by atomic absorption spectroscopy. Plasma K concentration remained constant (3.49 +/- 0.09 mM K/L of plasma; mean +/- SEM) throughout the study. Erythrocyte potassium concentration decreased from 93.10 +/- 1.94 mM K/L of erythrocytes on day...
McKeever KH, Hinchcliff KW, Schmall LM, Muir WW.Exercise-induced changes in renal function were examined during steady-state submaximal treadmill exercise in six unfit mares. Horses were randomly assigned to either an exercise or parallel control (no exercise) trial on day 1 and the alternate trial 1 wk later. The mares ran on a treadmill, set at a 6 degrees incline, for 1 h at 55-60% of maximal heart rate. Exercise significantly (P less than 0.05) increased plasma osmolality, plasma [K+], urine flow (+ 45%), Na+ excretion (+ 371%), K+ excretion (+ 57%), osmotic clearance (+ 32%), Na+ clearance (+ 391%), K+ clearance (+ 33%), and fractional...
Bohanon TC, Schneider RK, Weisbrode SE.Six normal horses received 3 intra-articular injections of sodium monoiodoacetate (MIA) in the distal intertarsal (DIT) and tarsometatarsal (TMT) joints of one hindlimb. Injections were at three week intervals, and post injection pain was controlled with routine administration of phenylbutazone for five days following each injection. All horses underwent a gradually increasing exercise programme consisting of walking and trotting beginning one week after the first injection and continuing for 24 weeks. All treated joints showed increasingly severe radiographic evidence of degenerative joint di...
Gomez DE, Buczinski S, Darby S, Palmisano M, Beatty SSK, Mackay RJ.Use of different analyzers to measure electrolytes in the same horse can lead to different interpretation of acid-base balance when using the simplified strong ion difference (sSID) approach. Objective: Investigate the level of agreement between 2 analyzers in determining electrolytes concentrations, sSID variables, and acid-base disorders in sick horses. Methods: One hundred twenty-four hospitalized horses. Methods: Retrospective study using paired samples. Electrolytes were measured using a Beckman Coulter AU480 Chemistry analyzer (PBMA) and a Nova Biomedical Stat Profile (WBGA), respectivel...
Kareskoski AM, Reilas T, Sankari S, Andersson M, Güvenc K, Katila T.Seminal plasma (SP) is a mixture of contents from the testes, epididymides and accessory sex glands. The sperm concentration is highest in the first few jets, or fractions, of the ejaculate, and the composition of SP varies between these fractions because accessory gland secretions are released in a specific order. The aim of this study was to compare the levels of Na, Cl, K, Mg, Ca, inorganic phosphate (Pi) and the enzymes alkaline phosphatase (AP), acid phosphatase (ACP) and β-glucuronidase (BG) in the different fractions of the ejaculate and in different stallions. All semen collections we...
Bertone JJ, Traub-Dargatz JL, Fettman MJ, Wilke L, Wrigley RH, Jaenke R, Paulsen ME.Sequential reciprocals of serum creatinine concentration and sodium sulfanilate clearance half-times were used to monitor a horse with chronic renal failure. The horse was diagnosed as having polycystic kidney disease; at least one cyst was of distal tubular origin. Using the plots of the sequential data, a reasonably accurate prediction was made for complete renal decompensation to develop.
Magalhaes HB, Canuto LEF, Canisso IF.The objectives of this study were to determine (i) the usefulness of serial assessment of mammary gland electrolytes concentrations and correspondent pH to detect impending parturition in jennies; and (ii2) the associations between mammary gland secretions, and gestation length, foal sex, maternal, placental, and foal birth weights. Multiparous jennies (n = 37) were monitored daily from 350 to 355 days of gestation until parturition. The pH of mammary gland secretions was assessed daily with a hand-held device. Aliquots of mammary secretions were frozen daily and then retrospectively assesse...
Gasthuys F, Messeman C, De Moor A.The influence of hypertonic NaCl 7.2% infusion (4 ml/kg of body weight [BWT]) on plasma (PV) and blood (BV) volumes, sodium (Na), chloride (Cl), potassium (K) plasma concentrations, osmolality (Osm), total protein content (TP), packed cell volume (PCV) and red blood cell count (RBC) was studied in five standing and anaesthetized ponies (standard halothane anaesthesia). Arterial blood gases were followed in the anaesthetized ponies. Isotonic NaCl 0.9% (4 ml/kg of BWT) was used as a placebo in the standing ponies. Isotonic solution in the standing ponies induced few changes: only small decreases...
Tessier GJ, Traynor TR, Kannan MS, O'Grady SM.When the equine tracheal epithelium is mounted in Ussing chambers and bathed in plasma-like Ringer solution, the tissue generates a lumen-negative transepithelial potential (PD) of 22 mV and a short-circuit current (Isc) of 70-200 microA/cm2. Mucosal addition of 10 microM histamine produces a transient increase in the Isc followed by a return to baseline or below. Mucosal addition of 2 microM diphenhydramine inhibits the Isc response to mucosal histamine, whereas 100 microM mucosal cimetidine produces no effect. The average initial increases in Isc over time for mucosal vs. serosal histamine a...
Mancini RA, Ramanathan R.Injection-enhancement of beef with lactate improves color stability; however, the mechanism is unclear. Thus, our objectives were to assess the effects of sodium lactate on equine myoglobin redox stability in vitro. Oxymyoglobin at pH 5.6 (50mM sodium citrate) and pH 7.4 (50mM sodium phosphate) was incubated at 4°C with lactate (0, 5, 10, 100, or 200mM) and myoglobin redox form was determined using absorbance spectra. Metmyoglobin formation at pH 5.6 and 7.4 was significantly (P<0.05) decreased by lactate at concentrations of 100 and 200mM. In general, increasing lactate concentration from...
Tofé E, Muñoz A, Castejón F, Trigo P, Castejón-Riber C, Gómez-Díez M, Riber C.The influence of hydration prior to exercise on hormonal response to exercise was investigated in horses, divided into two groups, control (n=11) and dehydrated (n=53). They were also classified according to their body weight in A (≈ 350 kg), B (351-450 kg) and C (≈ 451 kg). Horses covered 60 m on a track pulling a carriage loaded with 2, 2.25 and 2.5 times their body weight, for A, B and C. Blood samples were taken at rest, after exercise and during recovery. Electrolytes, albumin, renin, angiotensin and aldosterone concentrations were measured. Dehydrated and control horses had higher al...
Mueller PO, Hunt RJ, Allen D, Parks AH, Hay WP.The effect of intraperitoneal sodium carboxymethylcellulose (SCMC) administration on clinical outcome and survival was evaluated in horses undergoing exploratory celiotomy for acute gastrointestinal disease. Comparison of variables was made retrospectively between 44 horses that had SCMC and 92 horses (controls) not treated with SCMC. Mean age, body weight, heart rate, packed cell volume and plasma total protein of horses at admission, and convalescent period were not significantly different between control and SCMC groups. No significant differences were noted between control horses and SCMC ...
Gossett KA, French DD, Cleghorn B, Church GE.L-Lactic acid and D,L-lactic acid infusion in ponies resulted in metabolic acidosis with high anion gap (AG). Increased AG was explained entirely by increased blood L- and D-lactate concentrations. Hydrochloric acid infusion caused metabolic acidosis with decreased AG. Saline (NaCl) infusion caused mild metabolic acidosis, with no significant change in AG. Plasma K+ concentration was decreased by all types of infusions, with a maximum of 0.50, 0.25, 0.40, 0.50 mmol/L below baseline at the end of infusion in the L-lactic acid-, D,L-lactic acid-, HCl-, and NaCl-infused ponies, respectively. Only...
Morley PS, Desnoyers M.A 3-day-old Quarter Horse colt was examined because of signs of severe depression, discomfort, and abdominal straining. The foal seemed disoriented, and the abdomen was tense and distended ventrally. The differential diagnoses included ruptured urinary bladder, retained meconium, septicemia/bacteremia, and neonatal maladjustment syndrome. Serum biochemical analysis revealed marked hyponatremia, hypochloremia, and moderate hyperkalemia, as well as mildly high urea, creatinine, and phosphorus concentrations. The primary differential diagnosis at this time was ruptured urinary bladder. Abdominoce...
Shupe JL, Eanes ED, Leone NC.Sodium fluoride (5 mg/kg of body weight) was fed for 20 months to horses with hereditary multiple exostoses (HME), a skeletal disorder that primarily affects endochondral bones during skeletal development. Rib biopsies were performed on both HME horses not fed fluoride (control) and HME horses that were fed fluoride to obtain comparable specimens for chemical analyses and x-ray diffraction. Fluoride content of the rib from a horse fed fluoride for 20 months was approximately 20 to 30 times higher than that from a control horse. Fluoride content of the bone tumors was higher than those of norma...
Lloyd DR, Evans DL, Hodgson DR, Suann CJ, Rose RJ.We examined the effects of sodium bicarbonate in 6 Thoroughbred horses during submaximal and maximal treadmill exercise. Cardiorespiratory function was assessed together with the effect on exercise capacity by determining the run time to fatigue at maximal intensities. To discriminate between sodium bicarbonate's alkalinising effects and the fluid shifts that could result from the high osmotic load, we administered an equimolar solution of sodium chloride as a control. The horses were given sodium bicarbonate (1 g/kg bwt) or an equivalent number of moles of sodium chloride by nasogastric tube....
von Engelhardt W, Rösel E, Rechkemmer G.Short circuit current (ISC) and transepithelial conductance (gt) across sheets of epithelia were measured in the caecum, the proximal and the distal colon of pig, sheep, pony, rat and guinea pig. The electrical parameters underline the basic segmental and species differences. The diversity of ISC demonstrates the different nature of electrogenic transport mechanisms, and data clearly show the heterogeneity with respect to transport mechanisms along the large intestine in the various species. The great differences in amiloride sensitive ISC indicate the variabilities in the electrogenic Na tran...
Coruzzi G, Poli E, Montanari C, Bertaccini G.1. Uterine motility was studied in vitro in the myometrial tissue obtained from pregnant and non-pregnant mares. 2. The spontaneous contractions of the preparations were not modified by tetrodotoxin, by anticholinergics, antiadrenergics, histamine H1 and H2 blockers, antiserotoninergic and opioid antagonists; but disappeared in Ca2+ and Na+ free medium. 3. beta 2-adrenergic stimulants like salbutamol and hexoprenaline and the calcium channel blockers nifedipine and verapamil were effective inhibitors of the amplitude of phasic contractions (ID50S for salbutamol and nifedipine were 7.7 nM and 1...
Marlin DJ, Scott CM, Mills PC, Louwes H, Vaarten J.The administration of 41 of an isotonic, plasma-like oral rehydration solution (ORS) with an osmotic skeleton and 41 of water (water; no osmotic skeleton), were evaluated in five thoroughbred horses. Solutions were administered by nasogastric tube 4 h after feeding. Uptake of deuterium, concentrations of plasma sodium, potassium, chloride, glucose, total protein and packed cell volume, pH, PCO2, HCO3-, total CO2, actual base excess, standard base excess, plasma volume and weight loss were assessed both at rest, and during and after exercise on a treadmill. Each horse underwent four experimenta...
Keenan DM.Changes in concentration of a number of blood metabolites in 30 thoroughbred horses were recorded after an 1110 metre race. No significant changes occurred in blood urea or aspartate aminotransferase during the three hours after racing. Plasma sodium, potassium and calcium levels were increased immediately after racing but had returned to normal one hour after racing. Plasma phosphate showed a significant fall in concentration one hour after racing. Creatinine and lactic acid concentrations were elevated ten minutes after racing and although they subsequently decreased, the level of lactic aci...
Migliorisi A, Barger A, Austin S, Foreman JH, Wilkins P.Hyponatremia is common in horses with bacterial pleuropneumonia, but no further characterization of this abnormality has been reported. Objective: Describe admission plasma sodium concentration ([Na]) in horses with septic pneumopathy and evaluate any association of plasma [Na] with markers of systemic inflammation. Methods: Medical records of horses >1 month of age that between 2008 and 2021 had a transtracheal aspirate (TTA) performed, abnormal TTA cytology, positive TTA culture, pulmonary disease on ultrasonography, radiography or both, and plasma [Na] assessed by direct ion-selective-e...
Schmall LM, Muir WW, Robertson JT.The effects of treatment with small volume hypertonic (2400 mOsm/litre) and isotonic (300 mOsm/litre) saline on serum electrolyte and biochemical concentrations, haemograms and blood gases were evaluated in 12 horses using a haemorrhagic shock model. Intravascular catheters were placed surgically for sample collection prior to anaesthesia. Controlled haemorrhage was initiated and continued until mean systemic pressure reached 50 to 60 mmHg. Hypertonic or isotonic saline (2 litres) was administered by intravenous infusion and data collected for 2 h. Following haemorrhage, packed cell volume (PC...
Lloyd KC, Stover SM, Pascoe JR, Pool RR, Kurpershoek C.The effect of gentamicin sulfate, unbuffered and buffered with sodium bicarbonate, on synovial fluid and membrane of clinically normal equine joints was evaluated. Thirty-six adult horses with clinically normal antebrachiocarpal joints were allotted to 6 treatment groups of 6 horses each. One antebrachiocarpal joint in each horse was chosen for treatment. Group-1 horses were given gentamicin (3 ml; 50 mg/ml); group-2 horses were given sodium bicarbonate (3 ml; 1 mEq/ml); group-3 horses were given gentamicin (3 ml; 50 mg/ml) and sodium bicarbonate (3 ml; 1 mEq/ml); group-4 horses were not treat...
Amann RP, Cristanelli MJ, Squires EL.Motility and fertility of frozen-thawed semen differs greatly amongst stallions. Differences in seminal plasma might be one cause of this variation. For 8 ejaculates from each of 17 stallions, seminal plasma was saved at -20 degrees C and spermatozoa were cryopreserved. Based on post-thaw sperm motility, seminal plasma samples from 7 stallions (2 good, 3 variable, 2 poor sperm motility) were selected for measurement of electrolytes, protein content and analysis by sodium dodecylsulphate gel electrophoresis (10% gel, Coomassie blue stain). Variation in seminal plasma was significant (P less tha...
Fielding CL, Magdesian KG, Carlson GP, Rhodes DM, Ruby RE.To apply the principle of sodium dilution to calculate the changes in the extracellular fluid (ECF) volume (ECFV) and intracellular fluid volume (ICFV) that occur during dehydration and rehydration in horses. Methods: 8 healthy horses of various breeds. Methods: Horses were dehydrated over 4 hours by withholding water and administering furosemide. Saline (0.9% NaCl) solution was administered IV during the next 2 hours (20 mL/kg/h; total 40 mL/kg). Horses were monitored for an additional hour following IV fluid administration. Initial ECFV was determined by use of multifrequency bioelectrical i...
Tarello W.A report from England has suggested that Chronic Fatigue Syndrome exists in equines and constitutes an emerging veterinary problem. Preliminary epidemiological studies seem to confirm the zoonotic implications of CFS. An arsenical drug, sodium thiacetarsamide, was administered to four horses with a diagnosis of Chronic Fatigue Syndrome (CFS), already treated unsuccessfully with different medications. The CFS-like lethargy, with accompanying symptoms and signs, of the four animals obtained a complete remission after intravenous treatment with this drug at low dosage (0.1 mg/kg/day). No adverse ...
Papasouliotis K, Tennant KV, Dodkin S, Mason J.Falcor 350 is a wet-reagent biochemistry analyser that is available for in-house use. The aim of this study was to compare the results produced by this analyser with those obtained by the KoneLab 30i that served as the reference instrument. Blood samples from 60 clinical cases were analysed for urea, creatinine, total proteins, albumin, creatine kinase, aspartate aminotransferase, alkaline phosphatase, total bilirubin, total calcium, phosphate, sodium, and potassium using both instruments. Good to excellent correlations (r s value) value) were identified for creatinine (0.88), total proteins (...
Deldar A, Fregin FG, Bloom JC, Davanipour Z.The effects of strenuous exercise on serum electrolytes, blood metabolites, and serum enzymes were studied in a group of 13 horses participating in a 50-mile endurance ride. Blood samples were collected before, during, and at the end of the ride, as well as 1 hour and 16 hours after the completion of the ride. There were significant changes in these values when preride values were compared with those of samples taken at different sample-collection periods. Significant (P less than 0.001) decreases were observed in serum concentrations of chloride, potassium, and calcium. A significant increase...
Sweeney CR, Scanlon T, Russell GE, Smith G, Boston RC.To determine application rate and effectiveness of sodium bisulfate to decrease the fly population in a horse barn environment. Methods: 12 privately owned farms in southeastern Pennsylvania. Methods: Application rates of sodium bisulfate were approximately 2.3 kg/stall, 1.1 kg/stall, and 0.5 kg/stall. Two or 3 stalls were treated, and 1 or 2 stalls were not treated (control stalls) at each farm. Farm personnel applied sodium bisulfate in treated stalls daily for 7 days. Fly tapes were hung from the same site in treated and control stalls. After 24 hours, the fly tape was removed, flies adheri...
Bos A, Compagnie E, Lindner A.Blood is collected for hematologic and biochemical analyses when racehorses perform poorly. However, racing affects most analyte levels; therefore, the timing of blood sampling can affect analyte levels and interpretations. Objective: This study aimed to determine if the blood variable levels returned to pre-racing levels 2 and 3 days post-racing. Methods: Blood was sampled from 17 healthy racehorses pre- and post-racing. The variables measured from plasma were albumin, cholesterol, creatinine, calcium (Ca), phosphorus (P), magnesium (Mg), sodium (Na), potassium (K), creatine phosphokinase (C...
Dirikolu L, Waller P, Waguespack ML, Andrews FM, Keowen ML, Gaunt SD.This study evaluated the usage of Beckman Coulter AU680 analyzers for measurement of TCO in horse serum, and the effect of sodium bicarbonate administrations on serum TCO levels in resting horses. Treatment of horses with sodium bicarbonate did not result in any adverse events. Mean TCO concentration was significantly higher from 1 to 8 h in the sodium bicarbonate-treated horses compared to the untreated controls. Within an hour, administration of sodium bicarbonate increased the TCO level from 31.5 ± -2.5 (SD) to 34.0 ± 2.65 (SD) mmol/L and at 2-8 h post-administration, the TCO l...
Denham J, Hulme A.Sodium bicarbonate administration in the hours prior to exercise has been used as a performance-enhancing substance in horses since the late 1980s. Although sodium bicarbonate administration to racehorses 24 hours before racing is a banned practice in most racing industries, whether or not it improves running performance in racehorses is currently unclear. The aim of this systematic review and meta-analysis was to establish whether or not acute sodium bicarbonate administration improves running performance in trained Standardbred and Thoroughbred horses. Seven randomized controlled trials, in...
Diaz-Espiñeira M, Escolar E, Bellanato J, De La Fuente MA.Atomic spectrometry has been used in 20 samples of equine urinary sabulous deposits in order to detect minor elements accompanying the predominant element, calcium, which is present in the form of calcium carbonate (calcite and/or vaterite). The elements measured have been (besides calcium) magnesium, sodium, potassium, iron, copper and manganese. Phosphates, sulphates and silica are frequently present as minor constituents of equine urinary sabulous deposits and uroliths, but their detection can be difficult by infrared (IR) spectroscopy in the original samples due to overlapping with the ban...
