Topic:Hemoglobin
Hemoglobin is an iron-containing protein found in the red blood cells of horses, responsible for the transport of oxygen from the lungs to the tissues and the return of carbon dioxide from the tissues to the lungs. It plays a vital role in maintaining cellular respiration and energy metabolism. The structure and function of hemoglobin can be influenced by various factors, including genetics, age, and health status. Research into equine hemoglobin includes studies on its biochemical properties, the impact of different physiological and pathological conditions on its levels, and its importance in performance and endurance. This page compiles peer-reviewed research studies and scholarly articles that explore the characteristics, regulation, and clinical implications of hemoglobin in equine physiology and health.
Physiological adjustments of haematological profile during the last trimester of pregnancy and the early post partum period in mares. The aim of the study was to assess changes in some haematological parameters of periparturient mares from the last three months of pregnancy until the third week after foaling. The study was carried out on 15 healthy pregnant mares (Group A) and 7 healthy non-pregnant non-lactating mares (Group B). Blood samples were collected by jugular venipuncture into EDTA tubes and tested for Haematocrit (Hct), Red Blood Cell (RBC), Haemoglobin (Hb), Platelets (Plt) and White Blood Cell (WBC). Peripheral blood smears were also performed to assess changes in the leucocyte differential count. Group A showed...
Acute exercise does not induce an acute phase response (APR) in Standardbred trotters. The purpose of the study was to investigate whether acute strenuous exercise (1600- to 2500-m race) would elicit an acute phase response (APR) in Standardbred trotters. Blood levels of several inflammatory markers [serum amyloid A (SAA), haptoglobin, fibrinogen, white blood cell count (WBC), and iron], muscle enzymes [creatinine kinase (CK) and aspartate transaminase (AST)], and hemoglobin were assessed in 58 Standardbred trotters before and after racing. Hemoglobin levels increased and iron levels decreased 12 to 14 h after racing and haptoglobin concentrations, white blood cell counts, and i...
Evaluation of health status of horses immunized with snake venom and montanide adjuvants, IMS 3012 (nanoparticle), ISA 206 and ISA 35 (emulsion based) during polyvalent snake antivenom production: hematological and biochemical assessment. Several biochemical and hematological changes in horses are observed during production of snake antivenom. Although conventional adjuvants like Freund's (Complete and Incomplete) are good immunopotentiators, they produce considerable local reactions in animals. Variety of commercial adjuvants, like montanide adjuvants, having high immunopotentiation and showing lesser side effects are available. The prime objective during antivenom production is to strike a balance between safety of immunized horses and efficacy of the product. In our earlier work, efficacy of montanide group of adjuvants in a...
Detection of efaproxiral (RSR13) and its metabolites in equine by liquid chromatography tandem mass spectrometry. Efaproxiral (RSR 13) is an experimental synthetic allosteric modifier of haemoglobin (Hb) that acts by increasing the release of oxygen from Hb to the surrounding tissues. It has been shown to increase maximum oxygen uptake (VO(2max)) in a canine skeletal muscle model. The ability to increase maximal muscle oxygen uptake makes efaproxiral a potential performance-enhancing agent and is therefore prohibited by the World Anti-Doping Agency. In this study, a method for the detection and elimination of efaproxiral in equine plasma and urine after a 2.5 g intravenous administration of efaproxiral ...
Hematologic and biochemical profiles in Standardbred mares during peripartum. The purposes of this study were to determine physiological changes occurring in hematologic and biochemical parameters in mares between the last month of gestation and the first week after parturition. If a significant change was observed with respect to the reference interval of an adult horse, a further aim of the study was to establish different reference intervals. Blood samples were collected from 62 healthy pregnant Standardbred mares. Seventeen nonpregnant and nonlactating mares were used as a control group. In pregnant mares, blood sampling was conducted every three days from 1 month b...
Clinical and clinicopathological factors associated with survival in 44 horses with equine neorickettsiosis (Potomac horse Fever). The epidemiology of equine neorickettsiosis (EN) has been extensively studied but limited clinical and clinicopathological data are available concerning naturally infected horses. Objective: Factors predictive of survival will be identified in horses diagnosed with EN. Methods: Convenience sample of 44 horses with EN admitted to 2 referral institutions. Methods: A retrospective study was performed. A diagnosis of EN was based on the presence of positive blood or fecal PCR. Results: The most common clinical signs included diarrhea (66%), fever (50%), anorexia (45%), depression (39%), colic (39%...
Physiological responses of young thoroughbred horses to intermittent high-intensity treadmill training. Training of young Thoroughbred horses must balance development of cardiopulmonary function and aerobic capacity with loading of the musculoskeletal system that can potentially cause structural damage and/or lameness. High-speed equine treadmills are sometimes used to supplement exercise on a track in the training of young Thoroughbreds because the horse can run at high speeds but without the added weight of a rider. We tested the hypothesis that intermittent high-intensity exercise on a treadmill of young Thoroughbred horses entering training can enhance development of aerobic capacity (VO2max...
Detection of myo-inositol tris pyrophosphate (ITPP) in equine following an administration of ITPP. Myo-Inositol tris pyrophosphate (ITPP) is a powerful allosteric modulator of haemoglobin that increases oxygen-releasing capacity of red blood cells. It is capable of crossing the red blood cell membrane unlike its open polyphosphate analog myo-inositol hexakisphosphate (IHP). Systemic administration of ITPP enhanced the exercise capacity in mice. There have been rumours of its abuse in the horse racing industry to enhance the performance of racing horses. In this paper, the detection of ITPP in equine plasma and urine after an administration of ITPP is reported. A Standardbred mare was admini...
Age and gender related changes in hematological parameters of thoroughbred foals. Hematological and biochemical profiles commonly are required in equine medicine. We studied hematological parameters including red blood cells (RBC), white blood cells (WBC), hemoglobin (Hb), hematocrit (PCV), differential leukocyte counts, mean cell volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC) in thoroughbred foals at different ages and for both sexes. Sixty healthy thoroughbred foals, 1 day, 3 days and 1 year old were used. Each age group consisted of 10 male and 10 female animals. We found significant differences related to age in RBC...
Structural and oxygen binding properties of dimeric horse myoglobin. Myoglobin (Mb) stores dioxygen in muscles, and is a fundamental model protein widely used in molecular design. The presence of dimeric Mb has been known for more than forty years, but its structural and oxygen binding properties remain unknown. From an X-ray crystallographic analysis at 1.05 Å resolution, we found that dimeric metMb exhibits a domain-swapped structure with two extended α-helices. Each new long α-helix is formed by the E and F helices and the EF-loop of the original monomer, and as a result the proximal and distal histidines of the heme originate from different protomers. Th...
Copper-associated hepatic cirrhosis in a Friesian horse. A 6-year-old Friesian stallion was examined because of signs of exercise intolerance, stiff gait and symmetrical hind weakness, and increased serum liver enzymes. On presentation, the horse showed muscle atrophy of the hindquarters. Neurological investigation showed no abnormalities. Laboratory findings revealed a prolonged prothrombin time and increased levels of alkaline phosphatase (AF), aspartate aminotransferase (ASAT), gamma-glutamyl-transferase (GGT), lactate dehydrogenase (LDH), and bile acids. Histological evaluation of the liver revealed severe cirrhosis and intracytoplasmic greyish ...
Patient-based feedback control for erythroid variables obtained using in-house automated hematology analyzers in veterinary medicine. Automated in-house diagnostic analyzers, most commonly used for hematologic and biochemical analysis, are typically calibrated, and then control materials are used to confirm the quality of results. Although this approach provides indirect knowledge that the system is performing correctly, it does not provide direct knowledge of system performance between control runs. Objective: The objectives of this study were to apply analysis of weighted moving averages to assess performance of hematology analyzers using animal patient samples from dogs, cats, and horses as they were analyzed and apply co...
Antioxidant effect of different vitamins on methemoglobin production: An in vitro study. Nitrite intoxication occurs frequently in ruminants and equines. The most common treatment of this disorder is administration of 1% methylene blue, although the use of some antioxidant agents e.g. vitamins and complementary treatment may also be useful. The aim of this study was to evaluate the in vitro antioxidative effects of some vitamins on methemoglobinemia induced by sodium nitrite. For this purpose the blood sample of a healthy dairy cattle was pre-incubated with three different concentrations (5, 10, 20 mmol L(-1)) of each vitamin (E, C, B1, A and a combination of vitamin E and vitamin...
Physiological changes in jeju crossbred riding horses by swim training. The changes in physiologic parameters by swim exercise duration were examined in five female well-trained Jeju crossbred riding horses that had riding experience of more than three years without swim training experience. The horses were performed with swim exercise for 10 min (60.0 m/min) once a day for 14 days. Physiologic characteristics and haematic parameters were measured before swimming, immediately after swimming, and after a 10 min rest at first day (D0), 7 days (D7), and 14 days (D14) of training. After 14 days of swim training, heart rate (p<0.05), blood glucose (p<0.05), lacta...
The influence of road transport on the activities of glutathione reductase, glutathione peroxidase, and glutathione-S-transferase in equine erythrocytes. Transport of horses may have significant impact on serum biochemical and hematologic analytes and resistance to infection. Objective: The aim of our study was to assess the influence of transport stress on selected enzymatic antioxidants in equine blood. Methods: The study was conducted on a group of 60 horses of different breeds and ranging in age from 4 to 10 years. Venous blood was collected immediately before loading horses onto trailers for 8 hours of transport (I), immediately after unloading them from the trailer (II), and after subsequent stall rest for 24 hours (III). Hemolysates of b...
Agreement between arterial partial pressure of carbon dioxide and saturation of hemoglobin with oxygen values obtained by direct arterial blood measurements versus noninvasive methods in conscious healthy and ill foals. To determine agreement between indirect measurements of end-tidal partial pressure of carbon dioxide (PetCO(2)) and saturation of hemoglobin with oxygen as measured by pulse oximetry (SpO(2)) with direct measurements of PaCO(2) and calculated saturation of hemoglobin with oxygen in arterial blood (SaO(2)) in conscious healthy and ill foals. Methods: Validation study. Methods: 10 healthy and 21 ill neonatal foals. Methods: Arterial blood gas analysis was performed on healthy and ill foals examined at a veterinary teaching hospital to determine direct measurements of PaCO(2) and PaO(2) along wit...
Sequence variations and two levels of MCT1 and CD147 expression in red blood cells and gluteus muscle of horses. MCT1-CD147 complex is the prime lactate transporter in mammalian plasma membranes. In equine red blood cells (RBCs), activity of the complex and expression of MCT1 and CD147 is bimodal; high in 70% and low in 30%. We studied whether sequence variations contribute to the bimodal expression of MCT1 and CD147. Samples of blood and cremaster muscle were collected in connection of castration from 24 horses. Additional gluteus muscle samples were collected from 15 Standardbreds of which seven were known to express low amounts of CD147 in RBCs. The cDNA of MCT1 and CD147 together with a promoter regi...
The workload and plasma ion concentration in a training match session of high-goal (elite) polo ponies. This study was designed to consider the complexity of the physical effort inherent to horses in polo competitions and the absence of reports in the literature on the effort, intensity and electrolyte changes resulting from a collective team training session aimed at preparing for a polo championship. Objective: To determine the effort and ion changes caused by an outdoor polo training match for a 25 goal handicap (elite) based on physiological variables including acid-base status (venous pH, PCO(2) and HCO(3)(-)), packed cell volume (PCV), haemoglobin (Hb), lactate, glucose, sodium, chloride a...
Efficacy of rabbit anti-thymocyte globulin in severe aplastic anemia. A combination of horse anti-thymocyte globulin and cyclosporine produces responses in 60-70% of patients with severe aplastic anemia. We performed a phase II study of rabbit anti-thymocyte globulin and cyclosporine as first-line therapy for severe aplastic anemia. Methods: Twenty patients with severe aplastic anemia treated with rabbit anti-thymocyte globulin were compared to 67 historical control cases with matched clinical characteristics treated with horse anti-thymocyte globulin. Results: Response rates at 3, 6 and 12 months were similar for patients treated with rabbit anti-thymocyte glob...
In-vitro hypocoagulability on whole blood thromboelastometry associated with in-vivo expansion of red cell mass in an equine model. In several species, there is a strong correlation between indicators of red cell mass (RCM) and thromboelastometry results. The horse has a reliable, temporary, polycythemia in response to phenylephrine infusion. Our objective was to evaluate the effects of an in-vivo increase in circulating RCM on thromboelastometry results in an equine model of transient polycythemia. Six healthy research horses had whole blood thromboelastometry with contact activator and tissue factor initiation after recalcification of citrated samples. Additional samples were frozen for thrombin-antithrombin (TAT). Compl...
Disturbance of oxidant/antioxidant equilibrium in horses naturally infected with Trypanosoma evansi. Oxidant/antioxidant equilibrium disturbance has already been reported in trypanosome infections by several authors. The present study was aimed to explore the possible oxidant/antioxidant disturbance in surra of naturally infected horses before and after treatment. Fifteen naturally infected horses were chosen to analyse erythrocytic indices, platelet counts, lipid peroxides (LPO), nitric oxide (NO), reduced glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) while six healthy animals acted as control. There was a highly significant (P<0.001) reduction in red blood cell (RBC) c...
Comparative evolutionary analyses of beta globin gene in eutherian, dinosaurian and neopterygii taxa. Comparative genomics and evolutionary analyses of conserved genes have enabled us to understand the complexity of genomes of closely related species. For example: β-globin gene present in human hemoglobin is one such gene that has experienced many genetic changes in many related taxa and produced more than 600 variants. One of the variant, HBS causes sickle-cell anemia in humans but offers protection against severe malaria due to Plasmodium falciparum. In the present study, we characterized and performed evolutionary comparative analyses of the ?-globin gene in different related and unrelated...
Effects induced by exercise on lymphocyte β-adrenergic receptors and plasma catecholamine levels in performance horses. The effect of dynamic exercise on complete blood cell count, lymphocyte β-adrenergic receptor and plasma catecholamine (adrenaline and noradrenaline) levels in horses performing different disciplines were investigated during rest and after exercise. Blood samples were collected from jumping horses (n=6), Arabian Endurance horses (n=6) and Standardbred trotters (n=6) before and immediately after competition. Dynamic exercise caused a significant increase in red blood cell count (Standardbred trotters: P=0.0012), haemoglobin concentration (jumping horses: P=0.001; Standardbred trotters: P=0.01)...
The effects of deferoxamine mesylate on iron elimination after blood transfusion in neonatal foals. Hepatic failure is one of the more common complications in foals requiring blood transfusion to treat neonatal isoerythrolysis. Iron intoxication is likely the cause of hepatic injury. Objective: To determine the effects of deferoxamine on iron elimination in normal foals. Methods: Thirteen neonatal foals. Methods: Randomized-controlled trial. At 1-3 days of age, foals received either 3 L of washed packed dam's red blood cells (RBC) or 3 L of saline IV once. Foals were treated with deferoxamine (1 g) or saline (5 mL) SC twice daily for 14 days. Foals were randomly assigned to 1 of 3 gr...
Morphological and biochemical changes in the blood of horses naturally infected with Gasterophilus sp. larvae. Gasterophilus sp. constitute a group of specific parasites, which larval forms are found in horses and other phylogenetically related species--donkeys, mules and zebras. Their invasion is associated with marked fluctuations of hematological and biochemical blood parameters, including the activity of many enzymes and the electrolyte concentration. The purpose of the study was to analyze changes in selected biochemical and morphological blood parameters of horses infected with botfly larvae. The experimental group was formed of horses infested by Gasterophilus sp. larvae whereas the control grou...
Paroxysmal nocturnal hemoglobinuria clones in severe aplastic anemia patients treated with horse anti-thymocyte globulin plus cyclosporine. Clones of glycosylphosphatidylinositol-anchor protein-deficient cells are characteristic in paroxysmal nocturnal hemoglobinuria and are present in about 40-50% of patients with severe aplastic anemia. Flow cytometry has allowed for sensitive and precise measurement of glycosylphosphatidylinositol-anchor protein-deficient red blood cells and neutrophils in severe aplastic anemia. Methods: We conducted a retrospective analysis of paroxysmal nocturnal hemoglobinuria clones measured by flow cytometry in 207 consecutive severe aplastic anemia patients who received immunosuppressive therapy with a h...
Gender differences in exercise–induced intravascular haemolysis during race training in thoroughbred horses. Exercise-induced intravascular haemolysis and "sport anemia" are widely reported in human sports medicine. It has been recognized also in horses, however, the clinical importance and the onset of this condition seem different than in human. In this study we investigated the episodes of intravascular haemolysis, indicated by the increase in plasma haemoglobin and the decrease in serum haptoglobin levels, after routine training sessions in race horses. Heart rate and changes in haematological parameters confirmed, that the exertion was relatively high. Intravascular haemolysis did not appear in ...
Babesiosis in equines in Pakistan: a clinical report. Equine babesiosis is a tick-borne haematological disease of equidae that can affect acutely, subacutely and chronically. The disease is manifested by intermittent fever, anaemia, icterus and haemoglobinuria. The authors describe the clinical, haematological and therapeutic aspects of babesiosis in equines at two units in Kotley and at two units in Jehlum of the Remount Veterinary and Farms Corps (RVFC). Animals on these units showed the signs of illness. On clinical examination, intermittent temperature, increased respiratory rate, anaemia, lacrimation, conjunctivitis and pale mucous membranes...
Characterization of the haem-uptake system of the equine pathogen Streptococcus equi subsp. equi. 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...
Changes in serum mineral concentrations, biochemical and hematological parameters in horses with pica. 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...