Iron is an essential trace mineral in horses that plays a significant role in various physiological processes, including oxygen transport, energy metabolism, and enzyme function. It is a key component of hemoglobin and myoglobin, proteins responsible for transporting oxygen in the blood and muscles, respectively. Iron is also involved in the function of certain enzymes and the synthesis of DNA. Horses typically obtain iron from their diet, with forages and grains being primary sources. However, both iron deficiency and overload can lead to health issues, such as anemia or hemosiderosis. This page compiles peer-reviewed research studies and scholarly articles that explore the metabolism, dietary requirements, and health implications of iron in equine physiology.
Schryver HF, Millis DL, Soderholm LV, Williams J, Hintz HF.The effect of dietary aluminum on the absorption, retention and pathways of excretion of calcium, phosphorus, magnesium, zinc, iron and copper was studied in balance trials in mature ponies in a three by three latin square experiment. A basal diet consisting of one third each of oats, beet pulp and a commercial pelleted, complete horse ration and containing 336 ppm aluminum was supplemented with AlC1(3) . 6H2O. The middle and high level aluminum diets contained 1370 and 4500 ppm aluminum respectively. There was little difference in effect between the middle level aluminum and basal diets. The ...
Penhallow RC, Brown-Mason A, Woodworth RC.The ability of human-derived cells in culture to bind, remove iron from, and grow in the presence of transferrins (Tf) isolated from the sera of species commonly included in tissue culture medium was investigated. Kinetic studies on HeLa cells reveal apparent first-order association rate constants of 0.43 min-1 for human Tf and 0.15 min-1 for equine Tf. Labeled chicken ovo-Tf and fetal bovine Tf were not recognized by the HeLa cells. Competition experiments with HeLa cells that use either isolated Tf or parent serum confirm these findings. Equilibrium binding experiments performed on HeLa cell...
Smith JE, DeBowes RM, Cipriano JE.Corticosteroid preparation was administered to 7 Shetland Ponies and 10 Quarter Horses. Serum iron concentration increased dramatically for 48 to 72 hours after the steroid treatment, whereas serum iron-binding capacity and serum ferritin concentration did not. An increase in available iron may allow bacteria to proliferate when ponies or horses are stressed or treated inappropriately with corticosteroids.
Smith JE, Cipriano JE, DeBowes R, Moore K.Values for serum ferritin, serum iron, and serum total-iron binding capacity were determined in 100 hospitalized horses. Six foals had iron deficiency, as indicated by low serum ferritin and iron concentrations. Twenty-eight horses had low serum iron content and normal or high serum ferritin content and were considered to have pseudo-iron deficiency, possibly in response to infection. Ten horses had serum ferritin concentrations that were quite high, probably indicating iron overload.
Schryver HF, Oftedal OT, Williams J, Cymbaluk NF, Antczak D, Hintz HF.Milk samples were obtained in early and/or late lactation from Przewalski horses, Hartmann's zebras, Grant's zebras, domestic horses, ponies and a mule mare made pregnant by embryo transfer. Samples were compared for their content of total solids, ash, calcium, phosphorus, magnesium, sodium, potassium, copper, zinc and iron. Milk from the Przewalski horses, Hartmann's zebra and the domestic horse had similar mineral composition and the content of minerals was higher in early than in late lactation. Milk from the domestic mule contained the lowest concentration of calcium, phosphorus and zinc b...
Piscator M.Cadmium exposure, metabolism, and effects are described especially in relation to dietary intakes. Data on dietary intakes in several countries have been complied from studies using the duplicate diet method or fecal analysis. These two methods seem to give more accurate data than estimates based on cadmium concentrations in food classes and food consumption (composite method). The present data on absorption and retention of ingested cadmium indicate that normally less than 5% is ingested, but absorption may increase in women who have iron deficiency. Earlier estimates of the critical concentr...
Chasteen ND, Antanaitis BC, Aisen P.A preliminary EPR investigation of iron accumulation in apoferritin has identified paramagnetic species generated during the early stage of iron deposition within the apoprotein shell. A featureless resonance at g' = 4.3, attributable to solitary high spin Fe3+ ions bound to the protein, is generated when Fe(II) is added to apoferritin at a level of 0.5 Fe/subunit (12 Fe/molecule) followed by air oxidation. This resonance accounts for 36% of the added iron. The remainder is EPR-silent and is probably present as oligomeric Fe3+ species. The intensity of the g' = 4.3 signal is reduced 3-fold upo...
Gromadzka-Ostrowska J, Zalewska B, Jakubów K, Gozlinski H.Changes in some trace minerals concentrations (calcium, inorganic phosphorus, magnesium, zinc, iron, copper, sodium and potassium) in blood plasma were investigated during a three-year period in Shetland pony mares. Blood plasma mineral concentrations were determined by the atomic absorption method and colorimetric method. The three-year averages were in micrograms/ml; Na 4630 +/- 168; K 277 +/- 3.8; Ca 171 +/- 3.8; P 31.5 +/- 0.74; Fe 1.92 +/- 0.14; Zn 1.07 +/- 0.04 and Cu 1.06 +/- 0.02. Two trace minerals (magnesium in inorganic phosphorus) showed only long-term tendency changes--upward or d...
Varma KJ, Powers TE, Powers JD, Spurlock SL.A reproducible experimental disease model in horses using Streptococcus zooepidemicus was developed. An intravenous challenge dose of 1 X 10(10) colony-forming units (CFU), followed 24 h later with another challenge of 1 X 10(8) CFU of Strep. zooepidemicus produced the desired disease model. The disease was characterized by depression, pyrexia, anorexia, abnormal lung sounds, inflammation of joints, moderate to severe lameness, gradual loss of condition and emaciation. The effects of the disease on hematology, serum chemical profile and different protein fractions were studied. The disease sta...
Eley CG, Ragg E, Moore GR.The reduction of horse and Candida krusei cytochromes c by ferrocyanide has been studied by 1H NMR spectroscopy and the reaction found to involve a precursor complex of ferrocyanide bound to ferricytochrome c (pH* 7.4, 2H2O, I = 0.12, and 25 degrees C). The electron transfer rate constants for the reduction of the two ferricytochromes by associated ferrocyanide were found to be the same at 780 +/- 80 sec-1 but the association constants for binding of ferrocyanide to ferricytochrome c were significantly different: horse, 90 +/- 20 M-1 and Candida, 285 +/- 30 M-1. The different association const...
Eamens GJ, Macadam JF, Laing EA.Four young horses grazing pastures near industrial plants developed illthrift, lameness and skeletal abnormalities characterised by periarticular enlargement of the long bones. The clinical signs and lesions were attributed to hypocuprosis induced by an excessive intake of zinc from pasture. High pasture intakes of iron may have further compounded the problem.
Harvey JW, Asquith RL, McNulty PK, Kivipelto J, Bauer JE.Packed cell volume, haemoglobin concentration, erythrocyte counts, erythrocyte indices, serum iron, iron binding capacities, total and differential leucocyte counts, platelet counts, total plasma protein, fibrinogen, haptoglobin and icterus index values were determined at 14 different ages in eight Thoroughbred and 14 Quarterhorse foals during the first year of life. Absolute neutrophil numbers in blood decreased and lymphocyte numbers increased during the first months. Absolute eosinophil numbers tended to increase until three months old. Haemoglobin concentration and packed cell volume decre...
Smith JE, Moore K, Cipriano JE, Morris PG.Occasionally, horses are given large amounts of iron to improve performance. Although iron deficiency could limit erythrocyte production and other functions related to nonhematological tissues, it probably only occurs in blood loss. We have developed an enzyme immunoassay for ferritin in equine sera and evaluated its relationship to iron stored in liver and spleen. Serum ferritin correlated significantly (P less than 0.0001) with the concentration of nonheme iron in the liver and spleen. It increased following iron therapy and decreased after phlebotomy. We conclude that serum ferritin provide...
Garrett BJ, Holtan DW, Cheeke PR, Schmitz JA, Rogers QR.Dried tansy ragwort, which contains pyrrolizidine alkaloids, was fed as 10% of a complete diet to ponies, with and without a mixture of additives. The additives provided a dietary supplement equivalent to 1% cysteine, 0.75% butylated hydroxyanisole, 200 micrograms of vitamin B12/kg of feed, and 5 mg of folic acid/kg of feed. The additives did not alter tansy ragwort toxicity, as assessed by survival time, liver changes, sulfobromophthalein (BSP) clearance rate, serum gamma-glutamyl transpeptidase activity, and plasma amino acid patterns. In ponies fed tansy ragwort, BSP clearance rate was a se...
Acland HM, Mann PC, Robertson JL, Divers TJ, Lichtensteiger CA, Whitlock RH.Six foals of three different breeds, born to healthy mares, appeared normal at birth, and died at two to five days of age with icterus, ataxia, head pressing, and terminal hepatic coma. Their livers were less than one-half normal weight. Most of the liver was dark red-brown and slightly rubbery. Histologically, these areas were characterized by severe bile ductule proliferation, mild portal tract fibrosis, and massive hepatocellular necrosis and lobular collapse. A small proportion of the liver, usually on the peripheral part of the lobes, was grossly light brown and slightly raised. Histologi...
Sayers DE, Theil EC, Rennick FJ.Cell-specific variations in apoferritin structure correlate with variations in iron metabolism that suggest functional specificity of the protein shell. Using EPR spectroscopy, we previously showed that vanadyl binds to specific sites on apoferritin, and that VO2+ binding is reduced by Fe(II) and Fe(III) (the natural substrates) and by metals known to influence iron storage (Chasteen, N. D., and Theil, E. C. (1982) J. Biol. Chem. 257, 7672-7677). Such observations suggest that the metal-binding site is important to apoferritin function and may define a location where the influence of cell-spec...
Hartikka P, Dahlbom M, Westermarck H.In four training stables five trotter horses of the Finnish coldblooded breed and seven warmblooded trotters were treated with a ferrissaccharin preparation (Hippiron, Hausmann) intravenously. A short increase in heart frequency after the injection was noted. The cold solution injections, less than + 15 degrees C, may cause dangerous reactions. All horses showed an enhanced appetite, a substantially livier habitus after treatment.
Rose RJ, Hodgson DR, Sampson D, Chan W.Plasma biochemical values were measured in 14 horses, before a 160 km endurance ride, immediately after 85 km, immediately after 160 km, after 30 min recovery period and the day after the ride. For statistical analysis, a group of 7 horses that completed the ride at a mean speed of 234 metres per min (m/min) (Fast Group) was compared with 7 horses that completed the ride at a mean speed of 144 m/min (Slow Group). Estimations were made of sodium, potassium, chloride, bicarbonate, glucose, creatinine, urea, bilirubin, iron, total protein, albumin, calcium, phosphate, cholesterol, alkaline phosph...
Rose RJ, Hodgson DR.Eleven horses were studied throughout a 12 week training schedule. Serial blood samples were taken for haematological analysis and an extensive biochemical profile, including the following parameters: sodium, potassium, chloride, bicarbonate, glucose, creatinine, urea, bilirubin, iron, total protein, albumin, alkaline phosphatase, aspartate aminotransferase, creatine kinase, gamma glutamyl transferase, calcium phosphate and cholesterol. There were few significant changes detected and it was concluded that routine haematological and biochemical screening has no useful role in assessing the fitn...
Ulvik RJ, Romslo I, Roland F, Crichton RR.Mitochondria mobilize iron from ferritin by a mechanism that depends on external FMN. With rat liver mitochondria, the rate of mobilization of iron is higher from rat liver ferritin than from horse spleen ferritin. With horse liver mitochondria, the rate of iron mobilization is higher from horse spleen ferritin than from rat liver ferritin. The results are explained by a higher affinity between mitochondria and ferritins of the same species. The mobilization of iron increases with the iron content of the ferritin and then levels off. A maximum is reached with ferritins containing about 1 200 i...
Arnbjerg J.Peroral application of iron salts in various types of anemia was previously considered atoxic. The increased use of iron has, however, led to an increasing number of poisoning in children, taking iron tablets for candy. There have only been reported a few number of spontaneous intoxications in animals, but experimentally it has been possible to produce fatal intoxications in various kinds of animal species. The clinical findings are quite similar in the various animals, starting with vomiting, bloody diarrhoea and metabolic acidosis. If the intoxication is severe, shock and coma may develop, a...
Donoghue S, Kronfeld DS, Berkowitz SJ, Copp RL.Four diets were fed to pony fillies for 40 weeks. One group received a basal diet low in carotene, designated mildly deficient. Other groups were fed basal diet plus vitamin A propionate equivalent to 12 (control), 1,200 (mildly intoxicated) or 12,000 (severely intoxicated) microgram retinol/kg body weight/day. The mildly deficient group exhibited impairment of growth and hematopoiesis with decreased serum concentrations of iron, albumin and cholesterol prior to depletion of liver vitamin A. Growth was depressed in mildly intoxicated and severely intoxicated fillies. The latter became debilita...
Crichton RR, Roman F, Roland F.The release of iron from horse spleen ferritin by the chelating agents desferrioxamine B, rhodotorulic acid, 2,3-dihydroxybenzoate, 2,2'-bipyridyl and pyridine-2-aldehyde-2-pyridyl hydrazone (Paphy) has been studied in vitro. Ferritin prepared by classical procedures involving thermal denaturation releases its iron less effectively than ferritin isolated by a modified procedure that avoids this step. Desferrioxamine B and rhodotorulic acid are the most effective in releasing iron from both preparations of ferritin. When FMN is added, iron release by desferrioxamine B, rhodotorulic acid, and 2,...
Esparza I, Brock JH.The effect of trypsin digestion on iron-saturated and iron-free (apo) human, rabbit, bovine, pig and horse tranferrins has been studied. Iron-binding fragments were produced only from iron-saturated pig and bovine transferrins although some cleavage of the polypeptide chain occurred in all cases. The apo-transferrins were generally degraded to a greater extent than the corresponding iron-saturated proteins. The ability of the different transferrins to donate iron to rabbit reticulocytes varied in the order rabbit approximately pig greater than human approximately horse greater than bovine. Try...
Smith HT, Millett F.Spectrophotometric titrations of five singly modified horse heart ferricytochromes c, specifically (trifluoromethyl)phenylcarbamylated (CF3PhNHCO-) or trifluoroacetylated (CF3CO-) at lysines-13, -72, and -79, were carried out. The CF3PhNHCO-Lys-13, Lys-79, and CF3CO-Lys-79 derivatives all underwent alkaline isomerization with loss of the 695-nm band to low-spin species with an apparent pK of about 8.9, as did the unmodified cytochrome. However, modification of lysine-72 appeared to alter the reaction pathway since the CF3PhNHCO-Lys-72 derivative isomerized to a high-spin form with an apparent ...
Tisserand JL, Boulard F, Deponge P.We studied a caecum-cannulated pony fed hay libitum in order to determine the mineral elements likely to cause deficiencies which decrease microbial activity in the caecum. During four successive 1-month periods, we observed the effects of adding 50 mg of iron, 1 mg of cobalt, 40 mg of copper and 200 mg of zinc, respectively. Except for the introduction of zinc, which greatly diminishes cellulolytic activity measured with the nylon bag technique, there was no significant modification in that activity as shown by pH, NH3-nitrogen, total nitrogen and volatile fatty acid production (table 1). It ...
Bertrand ML, Harris DC.To test whether the reactivity of ferritin iron is affected by the heat treatment used in ferritin isolation, we prepared ferritin from the same horse spleen with or without heating. Both samples exhibited similar reactivity upon reduction or chelation of iron.
Bertrand ML, Harris DC.To test whether the reactivity of ferritin iron is affected by the heat treatment used in ferritin isolation, we prepared ferritin from the same horse spleen with or without heating. Both samples exhibited similar reactivity upon reduction or chelation of iron.
Ramsay WN.The non-haem iron concentration was estimated in post-mortem liver samples from 51 horses (age range 1-25 years). Two were normal and 49 had been suffering from conditions that were not expected to have had long-term effects on iron metabolism. Muscle samples (splenius and biceps femoris) from 23 of these horses were also analysed. There was a highly significant age-related increase in the non-haem iron concentration in the liver (r = 0.635, p < 0.001), but not in the muscles, in which the iron concentration was much lower than in the liver.
Garrett BJ, Holtan DW, Cheeke PR, Schmitz JA, Rogers QR.Dried tansy ragwort, which contains pyrrolizidine alkaloids, was fed as 10% of a complete diet to ponies, with and without a mixture of additives. The additives provided a dietary supplement equivalent to 1% cysteine, 0.75% butylated hydroxyanisole, 200 micrograms of vitamin B12/kg of feed, and 5 mg of folic acid/kg of feed. The additives did not alter tansy ragwort toxicity, as assessed by survival time, liver changes, sulfobromophthalein (BSP) clearance rate, serum gamma-glutamyl transpeptidase activity, and plasma amino acid patterns. In ponies fed tansy ragwort, BSP clearance rate was a se...
Turner GA, Taylor DM.The interactions between tetravalent plutonium and horse serum proteins were studied in vitro by electrophoresis on cellulose acetate and by gel filtration. The results show that in horse serum, as in other mammalian sera, the plutonium is associated principally with the transferrin component of the beta1-globulins. The formation of the plutonium-transferrin complex requires the presence of HCO3-, and plutonium is displaced from the complex by excess iron, thus indicating that similar binding sites may be involved in the complexing of iron and plutonium. The plutonium complex is considered to ...
Sanmartí J, Armengou L, Viu J, Alguacil E, Civit S, Ríos J, Jose-Cunilleras E.Sparse information regarding plasma iron concentration in neonatal foals and its utility as an inflammatory marker in this population has been published. Objective: To determine the physiologic plasma iron concentration in neonatal foals. To assess its utility as an inflammatory marker to predict systemic inflammatory response syndrome (SIRS) and as a prognostic marker. Methods: Forty-seven ill neonatal foals admitted to a referral equine hospital were divided in 2 groups based on the SIRS criteria (24 SIRS and 23 non-SIRS). Two control groups of 43 hospital and 135 stud farm healthy neonatal ...
Lisiecki P, Sobiś-Glinkowska M, Mikucki J.Under iron-restricted conditions staphylococcal strains could utilize in vitro several animals body iron sources in form of bovine haemoglobin, hemin, lactoferrin and transferrin, ovotransferrin, horse myoglobin ferritin and cytochrome C. Spectrum of utilized iron sources was not dependent on species affiliation and kind of siderophores system. Strains isolated from clinical materials utilized largest spectrum of animal iron body sources.
Ott EA, Asquith RL.Thirty-three Thoroughbred and Quarter Horse yearlings were used in two experiments (18 in Exp. 1 and 15 in Exp. 2) to determine the influence of trace mineral (TM) supplementation on growth and bone mineral content in young growing horses from 340 to 452 d of age. In each experiment the yearlings were assigned at random within breed and sex outcome groups to one of three treatments. Horses were fed assigned concentrates individually to appetite for two 1.5-h feeding periods, daily and group-fed Coastal bermudagrass (Cynodon dactylon) hay in drylot paddocks at a rate of 1.0 kg/100 kg BW daily. ...
Yin A, Shen C, Huang Y, Yue M, Huang B, Xin J.Large areas of soils in China are contaminated with Cd and are deficient in Se. Therefore, here, we aimed to reduce Cd accumulation while increasing Se content in rice grain, and to elucidate the mechanisms associated. A greenhouse pot experiment was conducted to determine grain concentrations of Se and Cd upon foliar spraying of Se combined with the application of horse manure and/or fly ash to different contaminated soils containing Cd 0.51 (T1), 1.46 (T2), and 4.59 mg Cd kg (T3). The amount of Fe, Si, and Cd in root iron plaque, and concentrations of Cd and Si in rice tissues were also det...
Varma KJ, Powers TE, Powers JD, Spurlock SL.A reproducible experimental disease model in horses using Streptococcus zooepidemicus was developed. An intravenous challenge dose of 1 X 10(10) colony-forming units (CFU), followed 24 h later with another challenge of 1 X 10(8) CFU of Strep. zooepidemicus produced the desired disease model. The disease was characterized by depression, pyrexia, anorexia, abnormal lung sounds, inflammation of joints, moderate to severe lameness, gradual loss of condition and emaciation. The effects of the disease on hematology, serum chemical profile and different protein fractions were studied. The disease sta...
Hashimoto M, Nambo Y, Kondo T, Watanabe K, Orino K.In mammal circulation, ferritin-binding proteins (FBPs) are thought to be involved in clearance of circulating ferritin after complex formation with it through receptor-mediated uptake. However, there is no report on fetal FBP in fetal circulation. Although iron concentrations of fetal horse plasma were higher than those of adult horse plasma, plasma ferritin concentrations and ferritin-binding activities were found to be significantly lower in fetus than in adult. FBPs were purified from fetal or adult horse plasma on horse spleen ferritin-Sepharose 4B affinity column. Partially affinity-puri...
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...
Rifkind JM, Lauer LD, Chiang SC, Li NC.Oxidation studies of hemoglobin by Cu(II) indicate that for horse hemoglobin, up to a Cu(II)/heme molar ratio of 0.5, all of the Cu(II) added is used to rapidly oxidize the heme. On the other hand, most of the Cu(II) added to human hemoglobin at low Cu(II)/heme molar ratios is unable to oxidize the heme. Only at Cu(II)/heme molar ratios greater than 0.5 does the amount of oxidation per added Cu(II) approach that of horse hemoglobin. At the same time, binding studies indicate that human hemoglobin has an additional binding site involving one copper for every two hemes, which has a higher copper...
Aytekin I, Onmaz AC, Aypak SU, Gunes V, Kucuk O.The aim of this study was to compare hematological, some biochemical parameters, and serum trace element concentrations in horses with or without pica. Fifteen horses with pica (group I) and another 15 healthy horses without pica (group II) were used. The hematological parameters were not changed between the two groups. In group I, hemoglobin values were lower than those of group II. However, the difference in hemoglobin values between the two groups was not significant (P > 0.05). Serum iron and copper concentrations and the copper/zinc ratio were lower in group I than those of group I...
Schorr G.Serum iron concentration and iron-binding capacity were determined in 34 respectively 35 clinically healthy horses of different sex, with the age of 3 to 21 years. In the Warm blooded horse, the Half bred, the Haflinger horse, the Heavy horse and the Arabian Haflinger the mean serum iron concentration amounted to 253 +/- 66 micrograms/dl, 202 +/- 87 micrograms/dl, 166 +/- 67 micrograms/dl, 183 micrograms/dl and 366 micrograms/dl, while the iron-binding capacity in the Warm blooded horse, the Half bred, the Haflinger horse, the Thoroughbred, the Heavy horse and the Arabian Haflinger ran up to 4...
Martens RJ, Cohen ND, Chaffin MK, Waskom JS.To quantify and compare geochemical factors in surface soils from horse-breeding farms with horses with pneumonia caused by Rhodococcus equi (affected farms) and horse-breeding farms with no history of pneumonia caused by R equi (unaffected farms). Methods: Soil from 24 R equi-affected farms and 21 unaffected farms. Methods: Equine veterinary practitioners throughout Texas submitted surface soil samples from areas most frequented by foals, on R equi-affected and unaffected horse-breeding farms in their practice. Soil samples were assayed for the following factors: pH, salinity, nitrate, phosph...
Kohn CW, Jacobs RM, Knight D, Hueston W, Gabel AA, Reed SM.At birth, 24 Standardbred foals were assigned at random to 1 of 2 groups and were given a placebo supplement (group 1) or an iron supplement (248 mg of iron/treatment; group 2). Foals were given iron supplement or placebo 4 times during the second and third weeks after birth. Hematologic variables and general health were monitored until foals were 4 months old. Mean PCV in foals of both groups decreased during the first 2 weeks after birth, but values remained within adult horse reference ranges. During the first 6 weeks after birth, foal erythrocytes were smaller than adult horse erythrocytes...
Wong KS, Cheung HW, Choi TLS, Kwok WH, Curl P, Mechie SC, Prabhu A, Wan TSM, Ho ENM.Recent advances in label-free quantitative proteomics may support its application in identifying and monitoring biomarkers for the purpose of doping control in equine sports. In this study, we developed a workflow of label-free quantitative proteomics to propose plasma protein biomarkers in horses after administration with krypton (Kr), a potential erythropoiesis-stimulating agent. Plasma proteomes were profiled by using nanoliquid chromatography-high-resolution mass spectrometry. An in-house mass spectral library consisting of 1121 proteins was compiled using samples collected from geldings (...
Boss MA, Chris Hammel P.The influence of proton diffusion on nuclear magnetic resonance (NMR) relaxation was investigated in the presence of horse spleen ferritin at 7 T. Binary mixtures of water and glycerol were used to control diffusion within the range of 0.6-2.0 × 10(-9)m(2)/s, which was confirmed by pulsed gradient techniques. The effect of chemical exchange by hydrolysis between water and glycerol on relaxation was characterized with Carr-Purcell-Meiboom-Gill (CPMG) dispersion experiments. The relaxation rate enhancement of the protons due to ferritin was found to be inversely proportional to the diffusion co...
Sayers DE, Theil EC, Rennick FJ.Cell-specific variations in apoferritin structure correlate with variations in iron metabolism that suggest functional specificity of the protein shell. Using EPR spectroscopy, we previously showed that vanadyl binds to specific sites on apoferritin, and that VO2+ binding is reduced by Fe(II) and Fe(III) (the natural substrates) and by metals known to influence iron storage (Chasteen, N. D., and Theil, E. C. (1982) J. Biol. Chem. 257, 7672-7677). Such observations suggest that the metal-binding site is important to apoferritin function and may define a location where the influence of cell-spec...
Schryver HF, Millis DL, Soderholm LV, Williams J, Hintz HF.The effect of dietary aluminum on the absorption, retention and pathways of excretion of calcium, phosphorus, magnesium, zinc, iron and copper was studied in balance trials in mature ponies in a three by three latin square experiment. A basal diet consisting of one third each of oats, beet pulp and a commercial pelleted, complete horse ration and containing 336 ppm aluminum was supplemented with AlC1(3) . 6H2O. The middle and high level aluminum diets contained 1370 and 4500 ppm aluminum respectively. There was little difference in effect between the middle level aluminum and basal diets. The ...
Zhang B, Wilson PE, Watt GD.Ferritin catalyzes the oxidation of Fe2+ by O2 to form a reconstituted Fe3+ oxy-hydroxide mineral core, but extensive studies have shown that the Fe2+ to O2 stoichiometry changes with experimental conditions. At Fe2+ to horse spleen ferritin (HoSF) ratios greater than 200, an upper limit of Fe2+ to O2 of 4 is typically measured, indicating O2 is reduced to 2H2O. In contrast, a lower limit of Fe2+ to O2 of approximately 2 is measured at low Fe2+ to HoSF ratios, implicating H2O2 as a product of Fe2+ deposition. Stoichiometric amounts of H2O2 have not been measured, and H2O2 is proposed to react ...
Waheed MM, Meligy A, Alhaider AK, Ghoneim IM.Seminal plasma contains several microelements like Zn, Fe, Se, and Cu that affect sperm motility and male fertility. Biochemical evaluation of seminal plasma trace elements is important for assessing fertility and diagnosing male infertility. Unassigned: The present study was designed to evaluate the effect of seminal fluid trace elements on sperm parameters and fertility in Arabian horses. Unassigned: Ninety-four ejaculates from 25 Arabian stallions (4-27 years old) were used to investigate the effect of seminal fluid trace elements on semen parameters and fertility. Data divided according to...
Kadir FH, al-Massad FK, Fatemi SJ, Singh HK, Wilson MT, Moore GR.Reactions of reduced horse spleen ferritin with horse and Saccharomyces cerevisiae ferricytochromes c, cow ferricytochrome b5, sperm-whale metmyoglobin and Pseudomonas aeruginosa ferricytochrome c-551 were investigated by u.v.-visible spectrophotometry. In all cases the reduced ferritin reduced the ferrihaemoproteins. The rate of reduction varied from less than 0.2 M-1.s-1 for metmyoglobin to 1.1 x 10(3) M-1.s-1 for horse ferricytochrome c (0.1 M-phosphate buffer, pH 7.4, at 25 degrees C). We conclude that the mechanism of ferrihaemoprotein reduction involves long-range electron transfer throu...
Canola PA, Salles RF, Daneze ER, Sobreira MFR, Oliveira BE, Favero ML, Antonioli ML.The aim of the study was to compare and correlate levels of ferritin, transferrin, iron and APPs in healthy horses and those surgically treated for strangulating colic. On admission, measurements of inflammatory markers related to iron and total protein, fibrinogen, albumin, haptoglobin and ceruloplasmin were made. The study comprised 22 horses, divided into a control group (CG) of healthy horses (n = 10) and horses with surgically treated acute abdomen (n = 12), obstruction group (OG). The OG was subdivided according to the affected intestinal segment (small vs. large) and according to ou...
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