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.
Gálvez N, Fernández B, Sánchez P, Cuesta R, Ceolín M, Clemente-León M, Trasobares S, López-Haro M, Calvino JJ, Stéphan O, Domínguez-Vera JM.Transmission Electron Microscopy (TEM), X-ray Absorption Near Edge Spectroscopy (XANES), Electron Energy-Loss Spectroscopy (EELS), Small-Angle X-ray Scattering (SAXS), and SQUID magnetic studies were performed in a batch of horse spleen ferritins from which iron had been gradually removed, yielding samples containing 2200, 1200, 500, and 200 iron atoms. Taken together, findings obtained demonstrate that the ferritin iron core consists of a polyphasic structure (ferrihydrite, magnetite, hematite) and that the proportion of phases is modified by iron removal. Thus, the relative amount of magneti...
Yörük I, Deger Y, Mert H, Mert N.The serum concentrations of copper, zinc, iron, and cobalt and copper/zinc ratio were investigated in horses infected with equine herpesvirus-1 (EHV-1). Nine horses were naturally infected with the virus and nine healthy horses served as controls. The concentrations of copper, zinc, iron, and cobalt were determined spectrophotometrically in the blood serum of all horses. The results were (expressed in micrograms per deciliters) copper 2.80 +/- 0.34 vs 1.12 +/- 0.44, zinc 3.05 +/- 0.18 vs 0.83 +/- 0.06, iron 2.76 +/- 0.17 vs 3.71 +/- 0.69, cobalt 0.19 +/- 0.37 vs 0.22 +/- 0.45, and copper/zinc ...
Borges AS, Divers TJ, Stokol T, Mohammed OH.Detection of systemic inflammation, which is important for proper diagnosis and prompt treatment, can be challenging. Objective: Measurement of plasma iron concentration is a sensitive method for detecting systemic inflammation in horses compared with measurements of plasma fibrinogen concentration, a traditional marker for inflammation in the horse. Methods: Ninety-seven horses hospitalized with diseases causing systemic inflammation, 22 horses with localized inflammation, and 12 clinically normal horses were included in this study. Methods: A retrospective study was made on hospitalized hors...
Clauss M, Castell JC, Kienzle E, Schramel P, Dierenfeld ES, Flach EJ, Behlert O, Streich WJ, Hummel J, Hatt JM.To test whether mineral recommendations for horses are likely to guarantee adequate mineral provision for black rhinoceroses (Diceros bicornis), we investigated the apparent absorption (aA) of macro- and microminerals in eight black rhinoceroses from three zoological institutions in a total of 32 feeding trials with total faecal collection, with additional data from three unpublished studies (18 feeding trials). Feeds and faeces were analysed for Ca, P, Mg, Na, K, Fe, Mn, Cu, Zn and Co. The resulting aA coefficients, and the linear relationships of apparently absorbable dietary mineral content...
Newton JR, Woodt JL, Chanter N.Recurring respiratory infections can contribute to prolonged burdens of disease, especially in younger horses and better knowledge of factors and effective interventions, such as vaccines, should improve therapeutic and preventive strategies. Objective: To identify factors and infections associated with naturally occurring respiratory disease in recently weaned Welsh Mountain ponies maintained at pasture and to determine whether ponies vaccinated with an experimental inactivated bacterial vaccine had lower burdens of disease and infection compared to nonvaccinated controls. Transferrin allele,...
Mills PH, Ahrens ET.The rational development of new generations of MRI contrast agents (CAs) requires a scheme for predicting contrast enhancement. Previous contrast predictions have been based largely on empirical results in specific systems. Here we present a general theoretical model for evaluating the minimum concentration of T2 CA required for satisfactory image contrast. This analytic contrast model is applicable to a wide range of T2-type agents and delivery scenarios, and requires only a few readily evaluated parameters. We demonstrated the model by predicting contrast produced by superparamagnetic ferumo...
Nygaard TK, Liu M, McClure MJ, Lei B.Heme is a preferred iron source of bacterial pathogens. Streptococcus equi subspecies equi is a bacterial pathogen that causes strangles in horses. Whether S. equi has a heme acquisition transporter is unknown. Results: An S. equi genome database was blasted with the heme binding proteins Shp and HtsA of Streptococcus pyogenes, and found that S. equi has the homologue of Shp (designated SeShp) and HtsA (designated SeHtsA). Tag-free recombinant SeShp and SeHtsA and 6xHis-tagged SeHtsA (SeHtsAHis) were prepared and characterized. Purified holoSeShp and holoSeHtsA bind Fe(II)-protoporphyrin IX (h...
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 ...
Schejter A, Ryan MD, Blizzard ER, Zhang C, Margoliash E, Feinberg BA.Contrary to most heme proteins, ferrous cytochrome c does not bind ligands such as cyanide and CO. In order to quantify this observation, the redox potential of the ferric/ferrous cytochrome c-cyanide redox couple was determined for the first time by cyclic voltammetry. Its E0' was -240 mV versus SHE, equivalent to -23.2 kJ/mol. The entropy of reaction for the reduction of the cyanide complex was also determined. From a thermodynamic cycle that included this new value for the cyt c cyanide complex E0', the binding constant of cyanide to the reduced protein was estimated to be 4.7 x 10(-3) L M(...
Divers TJ, Cummings JE, de Lahunta A, Hintz HF, Mohammed HO.To determine whether equine motor neuron disease (EMND) could be induced in adult horses fed a diet low in vitamin E and high in copper and iron. Methods: 59 healthy adult horses. Methods: Horses in the experimental group (n = 8) were confined to a dirt lot and fed a concentrate low in vitamin E and high in iron and copper in addition to free-choice grass hay that had been stored for 1 year. Control horses (n = 51) were fed a concentrate containing National Research Council-recommended amounts of copper, iron, and vitamin E. The hay fed to control horses was the same as that fed to experimenta...
Pesch S, Bergmann M, Bostedt H.Seminal plasma is very important for sperm metabolism as well as sperm function and survival and transport in the female genital tract. Analysis of enzyme activities and concentrations of elements can estimate integrity and function of sperm cell membranes. In man much data are available about biochemical analyses of seminal plasma. However, not many studies have been conducted in horses yet. We collected ejaculates from 72 stallions, measured the volume, obtained seminal plasma by centrifugation and examined spermatozoa with light microscopy for motility, concentration, for dead sperm and mor...
Asano K, Suzuki K, Chiba M, Sera K, Matsumoto T, Asano R, Sakai T.The influence of atrioventricular block (AV-block) on the trace elemental status in a horse hair was studied. The particle-induced X-ray emission (PIXE) method has provided a reliable, rapid, easy, and relatively inexpensive diagnostic method. Twenty-five elements (Al, Br, Ca, Cl, Co, Cu, Cr, Fe, Hg, K, Mg, Mn, Na, Nb, Ni, P, Pb, Rb, S, Se, Si, Sr, Ti, Y, and Zn) in mane hair and serum were measured by the PIXE method. A horse hair with first- and second-degree AV-block contained significantly greater amounts of Br, Ca, Sr, and Zn than those of horses without electrocardiographic abnormalities...
Jacobsen S, Jensen JC, Frei S, Jensen AL, Thoefner MB.Early recognition of excessive inflammation and infectious complications after surgery, leading to early institution of therapy, reduces post operative discomfort and facilitates recovery. Because serum amyloid A (SAA) is a highly sensitive marker of inflammation, measurements of SAA and other acute phase reactants in the equine surgical patient may be valuable in assisting clinical assessment of post operative inflammation. Objective: To investigate changes in inflammatory markers after castration and to correlate levels of acute phase reactants with clinical severity of inflammation after ca...
Asano K, Suzuki K, Chiba M, Sera K, Asano R, Sakai T.The concentrations of 28 elements (Al, Br, Ca, Cl, Co, Cu, Cr, Fe, Ga, Hg, K, Mg, Mn, Mo, Na, Nb, Ni, P, Pb, Rb, S, Se, Si, Sr, Ti, V, Y, and Zn) were measured in mane hair by the particle-induced X-ray emission method. Except for Br, Cl, K, S, and P, the trace element concentrations in mane hair of horses are similar to literature values for human hair. The values obtained are not dependent on the horse's age, breed, and sex and could be used as reference values in the assessment of diseases and nutritional status in equines.
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...
Inoue Y, Matsui A, Asai Y, Aoki F, Matsui T, Yano H.We investigated the effect of exercise on iron metabolism in horses. Four horses were walked on a mechanical walker for 1 wk (pre-exercise). They then performed moderate exercise on a high-speed treadmill in the first week of the exercise and relative high in the second week and high in the third week. Serum iron was significantly lower in the third week of exercise than in the pre-exercise. Transferrin saturation (TS) was significantly lower in the first and third weeks of exercise than in the pre-exercise. Serum haptoglobin was significantly lower in the first week of exercise than in the pr...
Lansdowne JL, Bouré LP, Pearce SG, Kerr CL, Caswell JL.To compare laparoscopic dissection with-laparoscopic dissection combined with abdominal instillation of ferric hyaluronate gel for the treatment of experimentally induced adhesions in pony foals. Methods: 12 healthy pony foals. Methods: A serosal abrasion method was used to create adhesions at 4 sites on the jejunum (day 0). At day 7 laparoscopy was performed and the adhesions observed in each foal were recorded. In group-1 foals (n = 6), the adhesions were separated laparoscopically (treatment 1). In group-2 foals (n = 6), 300 mL of 0.5% ferric hyaluronate gel was infused into the abdomen aft...
Cowley AB, Lukat-Rodgers GS, Rodgers KR, Benson DR.N-Acetylmicroperoxidase-8 (1) contains heme and residues 14-21 of horse mitochondrial cytochrome c (cyt c). The two thioether bonds linking protein to heme in cyt c are present in 1, and the native axial ligand His-18 remains coordinated to iron. As an approach to probing structural or functional roles played by the double covalent heme-protein linkage in cyt c, we have initiated a study in which the properties of 1 are compared with those of a synthetic mono-His coordinated heme peptide containing a single covalent linkage (2). One consequence of the greater conformational restriction imposed...
Massányi P, Trandzik J, Nad P, Toman R, Skalická M, Koréneková B.To determine the seminal concentrations of copper, zinc, iron, cadmium, lead and nickel in bulls, rams, boars, stallions and foxes and study their correlations. Methods: Semen samples were obtained, digested and analyzed by means of the atomic absorption spectrophotometer. Data were analyzed statistically with the Student's t-test and Scheffe's test using PC programs SAS and Excel. Results: The seminal copper concentration was significantly higher in ram [(2.49+/-0.18) mg/kg] and fox [(2.16+/-0.53) mg/kg] than that in bull [(1.64+/-0.21) mg/kg], boar [(1.64+/-0.28) mg/kg] and stallion (0.86 mg...
Hyyppä S, Höyhtyä M, Nevalainen M, Pösö AR.Iron is of key importance for aerobic metabolism, and natural feeds of the horse are fairly rich sources of iron. Accordingly, the known incidence of iron deficiency anaemia is apparently rare in performance horses; despite this, iron deficiency in performance horses continues to be of concern to trainers and veterinarians. Effects of exercise on plasma ferritin concentrations were therefore studied in Standardbreds, Finnhorses and half-bred riding horses. Blood samples were taken after a moderate exercise test on a racetrack, a competition exercise test on a treadmill and a race. Even moderat...
Barnés CM, Petoud S, Cohen SM, Raymond KN.The ability of ferritin as an Fe(II) detoxifier and Fe(III) storage protein is limited by its ability to recognize and incorporate Fe(II), which is then oxidized and mineralized at internal protein sites. The Cr(III) amine complex [Cr(N(CH(2)CH(2)NH(2))(3)(H(2)O)(OH)](2+) [abbreviated as Cr(TREN)] is a kinetically inert inhibitor of iron incorporation and mineralization in ferritin. Unlike other inhibitors, Cr(TREN) can only exchange its two aqua/hydroxy ligands. Competition studies between Cr(TREN) and Tb(III) binding have been performed in horse spleen ferritin (HoSF) to probe uptake of Fe(I...
Asano R, Suzuki K, Otsuka T, Otsuka M, Sakurai H.Concentrations of trace elements (As, Al, Pb, Cd, Hg, Se, Si, P, Na, K, Ca, Mg, Fe, Cu, Zn, Mn, Cr, Ni and Mn) in the mane hair obtained from 9 female and 15 male healthy racing Thoroughbred horses aged 2-5 years were analyzed by the inductively coupled plasma atomic emission spectrometry (ICP-AES) method. No significant differences between the female and male horses were observed in the mean concentrations of those minerals. Significantly positive correlations with age were observed in Cd (r=0.546, p<0.01) and Mo (r=0.733, p<0.001). Significantly negative correlations with age were observed i...
Hagen SJ, Latypov RF, Dolgikh DA, Roder H.Time-resolved spectroscopic studies of unfolded horse iron(II) cytochrome c have suggested that the imidazole side chains of His26 and His33 bind transiently to the heme iron on microsecond time scales, after photodissociation of a carbon monoxide ligand from the heme. Our studies of four variants of cytochrome c (horse wild type, horse H33N, horse H33N/H26Q, and tuna wild type), unfolded in guanidine hydrochloride at pH 6.5, demonstrate that these side chains are responsible for the observed microsecond spectral changes. As His33 and then His26 are eliminated from the horse wild-type sequence...
Casteel SW.The ubiquity and stability of metals in the environment make them unique as a pollutant or an essential dietary component. Metals are neither created nor destroyed by chemical processes but are redistributed in the environment. In combination with other elements, metal compounds and alloys are essential materials of the contemporary world. Inappropriate use or distribution in the environment leads to adverse health effects on all biologic systems, including horses. Gastrointestinal upset is a common feature of acute toxicosis with metals in general. Among the metals discussed, arsenic and inor...
Brommer H, Sloet van Oldruitenborgh-Oosterbaan MM.Forty-three Dutch Warmblood foals were divided at random into 3 rearing groups immediately after birth: a box-rest group, a box-rest with exercise group, and a pasture group. All stabled foals (box-rest and exercise groups) were fed freshly cut grass harvested from the same pastures on which the pasture group foals were grazing. Blood samples were obtained monthly for CBC and biochemical analyses. At 1-3 months of age, the foals at pasture were active but the foals in the box-rest and exercise groups were listless. Mean hemoglobin concentrations, PCVs, blood iron concentrations, and saturation...
Pearson EG, Andreasen CB.To evaluate the potential of excess dietary iron to cause hepatic lesions similar to those described in horses with suspected iron toxicosis or hemochromatosis. Methods: Prospective study. Methods: 6 adult male ponies. Methods: 4 ponies received 50 mg of iron/kg (22.7 mg/lb) of body weight each day by oral administration of ferrous sulfate, which contained 20% elemental iron; 2 ponies received only the carrier (applesauce). Complete blood counts, serum biochemical analyses, and hepatic tissue biopsies were performed, and serum iron concentrations were measured. Blood and tissue samples were ob...
McGreevy PD, Hawson LA, Habermann TC, Cattle SR.Recorded in several species including humans, geophagia or soil eating has been observed in both wild and domesticated horses and has generally been regarded as an indication of nutritional deficiency or "boredom". Studies of soils consumed by different species have led to several theories as to the identity of soil constituents that stimulate geophagia. In this study, geochemical analysis of 13 equine geophagic sites from different parts of Australia was undertaken. Significantly larger concentrations of iron and copper were found in soil samples from geophagic sites when compared to paired c...
Wooding FB, Morgan G, Fowden AL, Allen WR.The placenta is the only channel for transport of nutrients to the conceptus and the fetal nutrient demands increase exponentially to term. The 9 kDa calcium binding protein (calbindin, 9CBP) and the iron binding protein uteroferrin (UF) are proving to be reliable markers for epithelia that mediate active transcellular calcium and iron transport and the glucose transporter proteins (GT1 and GT3) for glucose transport by facilitated diffusion. Light and electron microscope immunocytochemistry have been used on perfusion fixed resin embedded material to establish the distribution of 9CBP, UF, GT...
Meehan M, Burke FM, Macken S, Owen P.Streptococcus equi possesses a haem-uptake system homologous to that of Streptococcus pyogenes and Streptococcus zooepidemicus. The system consists of two ligand-binding proteins (Shr and Shp) and proteins (HtsA-C) with homology to an ABC transporter. The haem-uptake system of S. equi differs from that of S. pyogenes and S. zooepidemicus in that Shr is truncated by two-thirds. This study focused on the SeShr, SeShp and SeHtsA proteins of S. equi. Analysis of shr, shp and shphtsA knockout mutants showed that all three proteins were expressed in vitro and that expression was upregulated under co...
Wooding FB, Morgan G, Fowden AL, Allen WR.The placenta is the only channel for transport of nutrients to the conceptus and the fetal nutrient demands increase exponentially to term. The 9 kDa calcium binding protein (calbindin, 9CBP) and the iron binding protein uteroferrin (UF) are proving to be reliable markers for epithelia that mediate active transcellular calcium and iron transport and the glucose transporter proteins (GT1 and GT3) for glucose transport by facilitated diffusion. Light and electron microscope immunocytochemistry have been used on perfusion fixed resin embedded material to establish the distribution of 9CBP, UF, GT...
McGreevy PD, Hawson LA, Habermann TC, Cattle SR.Recorded in several species including humans, geophagia or soil eating has been observed in both wild and domesticated horses and has generally been regarded as an indication of nutritional deficiency or "boredom". Studies of soils consumed by different species have led to several theories as to the identity of soil constituents that stimulate geophagia. In this study, geochemical analysis of 13 equine geophagic sites from different parts of Australia was undertaken. Significantly larger concentrations of iron and copper were found in soil samples from geophagic sites when compared to paired c...
al-Massad FK, Kadir FH, Moore GR.The origin of the 440 nm fluorescence of horse spleen ferritin and of Pseudomonas aeruginosa and Azotobacter vinelandii bacterioferritin has been investigated using a Nitro Blue Tetrazolium/glycinate colorimetric test specific for quiones [Paz, Flückiger, Boak, Kagan & Gallop (1991) J. Biol. Chem. 266, 689-692]. The results of the analysis indicate that ferritin and bacterioferritins contain quinones. A possible functional role of these quinones in iron uptake and release is described, as is the possibility that the presence of quinones in these proteins results from oxidative damage.
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 ...
Brosnahan MM, Erb HN, Perkins GA, Divers TJ, Borges AS, Osterrieder N.Research in humans has demonstrated that high serum iron (sFe) concentration can predispose to infection, and many infections subsequently result in alterations of host sFe. A decrease in sFe concentration is an early and sensitive indicator of systemic inflammation caused by tissue necrosis, bacterial infections, or endotoxemia in horses. Serum iron parameters in acute equine herpesvirus type 1 (EHV-1) infection have not been evaluated previously. Objective: To document the sFe response to EHV-1 infection and to determine whether or not significant differences in sFe concentration exist betwe...
Satterlee JD, Moench S.Proton hyperfine resonance assignments for cytochromes c from several species are currently being successfully pursued by several laboratories. These efforts focus mostly on the ferrous forms. In contrast to that work, we have pursued assignments of the proton hyperfine shifted resonances for horse and tuna ferricytochromes c. Our results indicate that assignments are nearly identical in those two proteins. Using the pre-steady state nuclear Overhauser effect, several additional assignments have been made for the tuna protein, whereas for the horse protein, the following protons have been assi...
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...
Latham CM, Dickson EC, Owen RN, Larson CK, White-Springer SH.To test the hypothesis that complexed trace mineral supplementation would increase antioxidant capacity and decrease muscle oxidative stress and damage in young horses entering an exercise training program, Quarter Horses (mean [Formula: see text] SD; 9.7 ± 0.7 mo) balanced by age, sex, and BW were assigned to receive complexed (CTM; n = 8) or inorganic (INORG; n = 8) trace minerals at -12 week relative to this study. Blood and muscle samples were collected before (week 0) and after 12 week of light exercise training surrounding a 1.5-h trailer stressor. Muscle glutathione peroxid...
Harvey JW, Asquith RL, Sussman WA, Kivipelto J.Twenty-one healthy Thoroughbred and Quarter Horse foals were studied from birth until 1 year of age. Foals had access to an iron-supplemented creep feed before weaning and were fed an iron-supplemented concentrate as part of their diet after weaning at 4 months of age. Initial blood samples were taken before foals were allowed to nurse. Serum iron concentration, total iron-binding capacity, and PCV decreased during the foal's first 24 hours of life. Serum iron concentration decreased rapidly from 446 +/- 16 micrograms/dl (mean +/- SE) at birth to 105 +/- 11 micrograms/dl at 3 days of age. Seru...
Rodríguez R, Cerón JJ, Riber C, Castejón F, Gómez-Díez M, Serrano-Rodríguez JM, Muñoz A.Clinical and laboratory findings were determined in 23 Andalusian horses in southern Spain that were positive for Theileria equi by PCR, including 16 mares at pasture (group A1) and seven stabled stallions (group B1). Five healthy mares at pasture (group A2) and five stabled stallions (group B2), all of which were negative for T. equi in Giemsa stained blood smears and by PCR, were used as controls. The most frequent clinical signs were anorexia, anaemia, depression and icterus (group A1), along with loss of performance or failure to train and depression (group B1). Thrombocytopoenia was evi...
Brommer H, Sloet van Oldruitenborgh-Oosterbaan MM.Forty-three Dutch Warmblood foals were divided at random into 3 rearing groups immediately after birth: a box-rest group, a box-rest with exercise group, and a pasture group. All stabled foals (box-rest and exercise groups) were fed freshly cut grass harvested from the same pastures on which the pasture group foals were grazing. Blood samples were obtained monthly for CBC and biochemical analyses. At 1-3 months of age, the foals at pasture were active but the foals in the box-rest and exercise groups were listless. Mean hemoglobin concentrations, PCVs, blood iron concentrations, and saturation...
Plumlee KH, Johnson B, Gardner IA.Records were reviewed of horses that had fatal injuries at California racetracks over a 16-mo period. Horses were categorized based on injury type, sex, age and breed. Arsenic, cadmium, copper, iron, lead, molybdenum and zinc concentrations were measured in the liver and kidneys from each horse. Arsenic and lead were not detected in any tissues. Liver heavy metal concentrations were not related to the injury type. Kidney iron concentrations were significantly (P < 0.05) higher in horses with ligament ruptures and in horses with fractured sesamoid, carpus or metacarpus/metatarsus bones. Live...
Huntley NF, Naumann HD, Kenny AL, Kerley MS.The domestic horse is used as a nutritional model for rhinoceros maintained under human care. The validity of this model for browsing rhinoceros has been questioned due to high prevalence of iron overload disorder (IOD) in captive black rhinoceros (Diceros bicornis), which is associated with high morbidity and mortality. Iron chelators, such as tannins, are under investigation as dietary supplements to ameliorate or prevent IOD in prone species. Polyphenolic compounds variably affect microbial fermentation, so the first objective of this experiment was to evaluate the effects of grape seed ext...
da Silveira BP, Gressler LT, Cargnelutti JF, Bordin AI, de Vargas AC.The ability of Rhodococcus equi to survive in macrophages and cause pneumonia in foals depends on vapA and rhbC genes, which produce the virulence-associated protein A (VapA) and the rhequichelin siderophore, respectively. Virulent R. equi acquires Fe from transferrin by unknown mechanisms. Our objectives were to determine the role of GAPDH in Fe homeostasis, to further characterize GAPDH, rhbC, and vapA expression under iron homeostasis, and to document the occurrence of rhbC gene in R. equi isolates. Therefore, vapA + R. equi was cultured under excessive, physiologic, and restricted iron c...
Strange R, Morante S, Stefanini S, Chiancone E, Desideri A.Extended X-ray absorbance fine structure measurements have been carried out on the initial Fe(III)-apoferritin complex at a Fe/subunit ratio of 2 in native and modified horse spleen apoferritin. Analysis of the data indicates that in the native protein the iron forms a protein-bound polynuclear cluster (Fe-Fe distance 3.4 A) with a first coordination sphere constituted by 5-6 low-Z atoms, e.g., nitrogen atoms, carboxylate-like ligands or oxo bridges between the iron atoms. Modification of Cys-126, a residue localized on the outer surface of the hydrophilic three-fold channels, with p-chloromer...
Giers J, Bartel A, Kirsch K, Müller SF, Horstmann S, Gehlen H.After submaximal exercise, blood values of eventing horses show physiological reactions. This prospective longitudinal study investigated blood parameters in 20 elite eventing horses before and after two-four-star cross-country rides. Using a mixed model adjusting for plasma volume shift, we assessed exercise-dependent parameters and compared blood values with reference ranges for healthy horses at rest. Following exercise, cortisol, triiodothyronine (T3) and thyroxine (T4) showed short-term increases, and superoxide-dismutase showed a small short-term increase. Hepatic values showed short-ter...
Su Y, Zhang Z, Wang L, Zhang B, Su L. subsp. () is one of the important zoonotic and opportunistic pathogens. In recent years, there has been growing evidence that supports the potential role of in severe diseases in horses and other animals, including humans. Furthermore, the clinical isolation and drug resistance rates of have been increasing yearly, leading to interest in its in-depth genomic analysis. In order to deepen the understanding of the characteristics and genomic features, we investigated the genomic islands, mobile genetic elements, virulence and resistance genes, and phenotype of strain ZHZ 211 (ST147), isolat...
Youssef MA, El-Khodery SA, Ibrahim HM.The aim of the present study was to evaluate the oxidative stress level and antioxidant trace elements status associated with lower airway disease in draft horses. For this purpose, venous blood samples were obtained from draft horses exhibiting signs of lower respiratory tract disorders (n = 83) and from control group (n = 20). Serum trace elements including selenium (Se), copper (Cu), zinc (Zn), manganese (Mn), and iron (Fe) were assayed. Serum malondialdehyde (MDA) and low-density lipoprotein (LDL) levels as well as plasma hydrogen peroxides (H₂O₂) concentration and activity of ...
Yoshinari K, Yuasa K, Iga F, Mimura A.A growth-promoting factor for human myeloid cells was purified to apparent homogeneity from horse serum by a combination of gel filtration, blue Sepharose affinity chromatography, Mono Q anion-exchange chromatography, Mono P chromatofocusing and sodium dodecyl sulfate polyacrylamide gel electrophoresis. The growth promoter was an iron-bound, single glycopolypeptide chain with a molecular weight of 84,000, an isoelectric point of 5.4 and an amino terminal sequence of Glu-Gln-Thr-Val-Arg-Trp-Cys-Thr-Val-Ser-Asn-His-Glu-Val-Ser-Lys-. According to the results of the amino acid sequence, iron bindi...
Mills PC, Roberts CA, Smith NC.To investigate the effects of ozone and airway inflammation on indices of oxidant injury in horses. Methods: 5 clinically normal horses and 25 horses referred for poor performance. Methods: Blood, tracheal wash, and bronchoalveolar lavage fluid samples were collected before and after ozone exposure (n = 5) or from clinical cases (n = 25), and were analyzed for reduced glutathione (GSH), glutathione disulfide (GSSG), and free and total iron (Fe) values. A scoring system (0 to 5) was used to assess airway inflammation on the basis of clinical signs and cytologic analysis of the tracheal wash and...
Asano K, Suzuki K, Chiba M, Sera K, Asano R, Sakai T.The concentrations of 28 elements (Al, Br, Ca, Cl, Co, Cu, Cr, Fe, Ga, Hg, K, Mg, Mn, Mo, Na, Nb, Ni, P, Pb, Rb, S, Se, Si, Sr, Ti, V, Y, and Zn) were measured in mane hair by the particle-induced X-ray emission method. Except for Br, Cl, K, S, and P, the trace element concentrations in mane hair of horses are similar to literature values for human hair. The values obtained are not dependent on the horse's age, breed, and sex and could be used as reference values in the assessment of diseases and nutritional status in equines.
Satué K, Fazio E, Cravana C, Medica P.During pregnancy, maternal erythropoietic expansion and fetal development require greater mobilization of available iron (Fe) stores. These adjustments in Fe metabolism in humans and rodents are largely mediated by the hormone hepcidin (Hepc), which controls the expression of ferroportin (Fpn), a transporter responsible for exporting Fe from stores to extracellular fluid and plasma. These mechanisms based on the regulation of Hepc on the availability of Fe during gestation in healthy mares remain unknown. The objective of this study was to determine the existence of interrelationships among co...
Mullaney TP, Brown CM.Newborn Shetland foals died of acute hepatic failure following oral administration of approximately 16 mg/kg body weight ferrous fumarate. Lesions in these foals were indistinguishable from lesions in foals given an oral digestive inoculant containing ferrous fumarate and were also similar to the syndrome characterised as 'toxic hepatopathy' in foals in the United States in 1983. We conclude that foals are susceptible to toxicity from low doses of iron compounds in the first few days of life. Vitamin E and selenium deficiency may contribute to this susceptibility.
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.
Wahl L, Vervuert I.The use of hair samples to assess the mineral intake of horses under practical conditions has recently been attracting increased interest. The aims of this study were to compare mineral analysis results in equine mane hair between three commercial laboratories and to determine the relationship between the mineral intake and mineral content in mane hair. Four warmblood horses (14 ± 3 years) were included in the study. Horses were fed hay ad libitum and a commercial mineral supplement to meet nutrient requirements under maintenance conditions. Mane hair from the hairline was collected with a sa...
Crichton RR.The researchers investigated the biochemical properties of ferritin, a protein responsible for iron storage in the body. They identified its distribution and structure, noting variations in different species and tissues. […]
Jacobsen S.Serum amyloid A (SAA) has become an indispensable part of the management of equine patients in general practice and specialized hospital settings. Although several proteins possess acute phase properties in horses, the usefulness of SAA exceeds that of other acute phase proteins. This is due to the highly desirable kinetics of the equine SAA response. SAA concentrations exhibit a rapid and pronounced increase in response to inflammation and a rapid decline after the resolution of inflammation. This facilitates the detection of inflammatory disease and real-time monitoring of inflammatory activ...
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...
