The study of blood in horses encompasses the examination of its components, functions, and its role in equine health and disease. Blood consists of various elements, including red blood cells, white blood cells, platelets, and plasma, each serving specific functions such as oxygen transport, immune response, clotting, and nutrient distribution. Analyzing blood parameters can provide insights into the physiological and pathological states of horses. Common blood tests in equine medicine assess parameters like hematocrit, hemoglobin concentration, and white cell counts to monitor health status, diagnose conditions, and guide treatment decisions. This page compiles peer-reviewed research studies and scholarly articles that explore the composition, function, and clinical applications of blood analysis in horses.
Nicpon J, Czerw P, Harps O, Deegen E.24 cases of salinomycin poisoning in horses occurring recently in Silesia are discussed. All of these horses, used for riding-purposes, were fed with concentrate containing 61 mg/kg salinomycin as faulty prepared by the manufacturer. Each horse received approximately two to three kilograms of this forage. All horses developed severe clinical signs of intoxication. Despite therapy eight horses died within three to six days. Ten others became recumbent and had to be euthanased. Only six horses survived. Clinical and laboratory examinations were performed and are discussed. Laboratory examination...
Jackson JA, Ducharme NG, Hackett RP, Rehder RS, Ainsworth DM, Shannon KJ, Erickson BK, Erb HN, Jansson N, Soderholm LV, Thorson LM.To determine whether laryngeal hemiplegia would increase transmural pulmonary artery pressure (TPAP). Methods: 6 horses. Methods: Horses were studied under 5 conditions: control conditions, after induction of left laryngeal hemiplegia, during obstruction of the left nostril, after placement of an instrumented tracheostomy, and after placement of an open tracheostomy. Horses were evaluated after being given saline solution and after being given furosemide. Methods: Horses were exercised on a high speed treadmill, using a maximum speed of 13 m/s. During each exercise, airway pressures, airflow, ...
Weiss DJ, Evanson OA.To determine the potential usefulness of tests for detection of platelet activation and platelet-leukocyte aggregates in horses. Methods: Blood from 3 healthy Thoroughbreds. Methods: Microscopic and flow cytometric assays were used to evaluate spontaneous platelet aggregation, platelet activation, and platelet-leukocyte aggregates. Platelet activation was detected by evaluation of binding of anti-human fibrinogen to unactivated and ADP-, thrombin-, thrombin agonist receptor peptide-, and platelet activating factor-activated platelets. Platelet-leukocyte aggregates were evaluated microscopicall...
Cunningham FM, Andrews M, Landoni MF, Lees P.Calcium ionophore A23187 induced time and concentration dependent production of immunoreactive leukotriene (LT) B4 by equine heparinized whole blood in vitro. Time dependent production of immunoreactive LTB4 by equine neutrophils and immunoreactive LTC4 by equine eosinophils in vitro was also demonstrated. The 5-lipoxygenase activating protein (FLAP) inhibitors, BAY X 1005 and BAY Y 1015, produced concentration dependent inhibition of ionophore-induced LTB4 synthesis by equine whole blood (mean +/- SEM IC50s n = 5; 6.14 +/- 0.28 microM vs. 12.30 +/- 0.75 microM for BAY Y 1015 and BAY X 1005, r...
Takahashi H, Nakaya T, Nakamura Y, Asahi S, Onishi Y, Ikebuchi K, Takahashi TA, Katoh T, Sekiguchi S, Takazawa M, Tanaka H, Ikuta K.It is believed that Borna disease virus (BDV), an etiological agent of progressive polioencephalomyelitis in horses and sheep, is closely associated with psychiatric disorders in humans since the prevalence of BDV is higher in psychiatric patients than in blood donors. We investigated whether or not BDVs in humans are derived from infected domestic animals, by characterizing the BDVs in blood donors and horses derived from the same region of Hokkaido island, Japan. The seroprevalences (2.6 to 14.8%) of BDV were significantly higher in the blood donors from four regions where most horse farms a...
Ellis JA, Steeves E, Wright AK, Bogdan JR, Davis WC, Kanara EW, Haines DM.The objective of this study was to determine whether the administration of modified-live equine herpesvirus (EHV-1) to young horses with residual maternal antibodies stimulated EHV-specific cytolytic responses, and whether these responses were crossreactive between EHV-1 and EHV-4. Eighteen clinically normal Belgian cross-foals were used in the study and were commingled in two adjacent pens. Skin biopsies were harvested from 16 foals within 24 h of birth and fibroblast cultures were established, expanded and cryopreserved. Beginning at approximately 10 weeks of age, 10 randomly chosen foals we...
Manohar M, Goetz TE, Sullivan E, Griffin R.The frusemide dose-response for attenuation of exercise-induced pulmonary capillary hypertension was studied in 7 healthy, exercise-conditioned Thoroughbred horses using previously described haemodynamic procedures. Four different doses of frusemide were tested: 250 mg regardless of bodyweight (amounting to 0.56 +/- 0.03 mg/kg bwt), 1.0 mg/kg bwt, 1.5 mg/kg bwt and 2.0 mg/kg bwt. Frusemide was administered i.v., 4 h before exercise. Haemodynamic data were obtained at rest and during treadmill exercise performed at 14.2 m/s on a 3.5% uphill grade; this workload elicited maximal heart rate of ho...
Motton DD, Roser JF.Recent evidence in our laboratory suggests that the cause of idiopathic subfertility/infertility in breeding stallions may originate in the testes at the luteinizing hormone (LH) receptor or postreceptor level. The objective of this research was to determine if LH receptor binding activity is altered in subfertile and infertile stallions. Six fertile, three subfertile, and three infertile stallions, ages 11-23 years, were classified according to normal semen parameters and pregnancy rates and then castrated in the breeding season. Blood was collected prior to castration, and plasma was stored ...
Gustafsson A, Båverud V, Gunnarsson A, Rantzien MH, Lindholm A, Franklin A.In Sweden there are several reports of mares developing acute colitis while their foals were being treated orally for Rhodococcus equi pneumonia with the combination of erythromycin and rifampicin. In this study 6 adult horses were given low oral dosages of these antibiotics, singly or in combination. Within 3 days post administration of erythromycin, in one case in combination with rifampicin, 2 horses developed severe colitis (one fatal). Clostridium difficile was isolated from one of the horses, whereas no specific pathogens were isolated from the other. Both horses had typical changes in b...
Singh AK, Jiang Y, White T, Spassova D.The performances of a radioimmunoassay method, a chemiluminescent immunoassay method, and a chemiluminescent-enzyme immunoassay method were evaluated for the analysis of cortisol and total thyroxine in blood samples obtained from dogs, cats, horses, and humans (reference samples). The analysis of cortisol in human and animal samples exhibited good precision, linearity, and recovery. The 3 methods gave comparable values for the ACTH-induced increase and the dexamethasone-induced decrease in cortisol concentrations in animal samples. The recoveries of total thyroxine from human samples, analyzed...
Essén-Gustavsson B, Ronéus N, Pösö AR.Histochemical and biochemical analyses were performed on muscle biopsies obtained after racing from the gluteus muscle of 18 standardbred trotters. Fibre type composition and enzyme activities varied among the horses. The percentage of type IIB fibres showed a positive correlation to the lactate dehydrogenase activity and a negative correlation to the citrate synthase activity. ATP concentrations in whole muscle after racing showed a negative correlation to both lactate and IMP concentrations. Within individual fibres, ATP concentrations varied markedly, with some type II fibres having values ...
Rivas LJ, Hinchcliff KW.To investigate the effect of i.v. administration of fluids on the furosemide-induced reduction in right atrial pressure (RAP) and relative change in blood volume (BV) of splenectomized mares. Methods: 5 splenectomized mares. Methods: RAP was measured by use of a micromanometer placed in the right atrium. Jugular venous blood was collected for measurement of hematocrit, plasma total protein concentration, and hemoglobin concentration. Right atrial pressure was recorded and blood samples were collected immediately before furosemide (1 mg/kg of body weight, i.v.) administration, then every 15 min...
Murphy D, Love S.Nine pony breed foals were reared indoors, then allocated to one of three groups infected with either 3.9 million (Group A) or 3.15 million (Group B) cold-conditioned third stage cyathostome larvae or kept as uninfected controls (Group C). The larvae were administered as a 'trickle' infection of 150000 larvae per dose, three times weekly. Blood biochemical and haematological analyses were performed weekly and faecal worm egg counts bi-weekly. Complete parasitological examinations were performed on all ponies at various times post-initial infection (PI): one infected animal at 9 weeks PI, four ...
Christley RM, Hodgson DR, Evans DL, Rose RJ.To compare the development of exercise-induced arterial hypoxemia in horses before and after training, and to determine whether increases in maximum oxygen uptake (VO2max) following training results in a greater degree of exercise-induced arterial hypoxemia. Methods: 13 three- to five-year-old. Standardbred geldings without clinical signs of respiratory or cardiovascular disorders. Methods: Horses were rested for 4 months prior to commencing a 16-week training program. Arterial blood was collected from the transverse facial artery during standardized exercise tests performed before and after 8...
Fuentes VO, Gonzalez H, Sanchez V, Fuentes P, Rosiles R.The toxic effect of neomycin on the horse kidney was studied. Twelve horses were used, and were divided at random into three groups of four. The first group was treated twice a day with 10 mg/kg I.M. for 15 days and then euthanised; kidney and liver samples were studied and no histopathological changes were observed. Group 2 was treated with neomycin sulphate as in group 1, and group 3 was used as control. Blood samples were taken at 8.00 h and 20.00 h daily from both neomycin treated and control horses. Serum creatinine, potassium, sodium and urinary creatinine remained without change. On day...
Lepage OM, Eicher R, Uebelhart B, Tschudi P.To evaluate applicability of a human osteocalcin (OC) immunoradiometric assay (IRMA) for use with equine serum and compare it with a bovine radioimmunoassay (RIA) previously proven valid for such samples, and to describe the effect of type and breed of horses on serum OC concentration. Methods: 100 healthy horses of either sex, classified as type I or II (draught or warmblood, respectively). Each type was represented by 2 breed groups, each comprising 25 horses. Methods: Blood samples were collected in the morning, and the serum was separated. Osteocalcin was measured, using commercially avail...
Rivas LJ, Hinchcliff KW, Kohn CW, Sams RA, Chew DJ.To describe changes in blood constituents of horses after oral and i.v. administration of sodium bicarbonate (NaHCO3), and to determine whether the changes are dose dependent. Methods: 6 adult Standardbred mares. Methods: 3 oral doses (1,500, 1,000, and 250 mg/kg of body weight) or 1 intravenous dose (250 mg/kg, 5% solution) of NaHCO3 in 3 L of water, or water (3 L orally), were given to the mares; then changes in blood constituents were measured. Access to food and water was denied during the experiment. Blood samples were collected immediately before treatment and at hourly intervals for 12 ...
Alexander SL, Roud HK, Irvine CH.To study the effect of hypoglycaemia on secretion rates of corticotrophin-releasing hormone (CRH), arginine vasopressin (AVP) and ACTH in a non-ruminant species, a non-surgical method was used to collect pituitary venous (PitVen) blood every 0.5 or 1 min from seven horses before and after insulin administration (0.4 U/kg i.v.). To assess the effect of PitVen cannulation on results, peripheral hormones were also measured before and after insulin in five horses without PitVen cannulae. Insulin administration lowered plasma glucose in all horses (P < 0.0001; paired t-test). Cortisol concentrat...
Dierenfeld ES, Hoppe PP, Woodford MH, Krilov NP, Klimov VV, Yasinetskaya NI.Circulating concentrations of alpha-tocopherol, beta-carotene, and lipids were quantified in 19 Przewalski horses (Equus przewalskii) inhabiting the steppes of Ukraine during June 1991. Foals (n = 3) had lower mean plasma alpha-tocopherol (4.7 micrograms/ml) and beta-carotene (0.3 microgram/ml) levels than did adults (n = 16; 6.6 and 0.7 micrograms/ml, respectively) and higher mean cholesterol concentrations (1.42 vs. 0.98 mg/ml). Mean triglyceride levels did not differ between foals and adults (0.46 mg/ml). Alpha tocopherol concentrations were substantially higher than those considered normal...
Weiss DJ, Evanson OA, Wells RE.To determine whether synthetic peptides containing the arginine-glycine-aspartate (RGD) sequence inhibit equine platelet function. Methods: For in vitro studies of blood, 3 healthy Thoroughbreds; for in vivo and ex vivo studies of administration of RGD-containing peptides, 4 young adult pony mares. Methods: Blood was incubated with and without addition of aspirin or RGD-containing peptides (RGDS, RPR 110885) and platelet aggregation responses and platelet adhesion to subendothelial collagen were determined. RPR 110885 was administered IV, and platelet function was evaluated. Platelet aggregati...
Sarkar P, McIntosh JM, Leavitt R, Gouthro H.Nimesulide is a nonsteroidal anti-inflammatory drug recently detected in equine blood and urine samples taken at the race track. The detection of the drug in a blood sample led to the identification of an unknown thin-layer chromatographic (TLC) spot in track urine samples as a metabolite of nimesulide. Characterization of the unknown TLC spot and comparison with the synthesized compound shows that the unknown TLC spot is a previously unreported equine metabolite of nimesulide. The metabolite was identified as resulting from the reduction of the nitro group on nimesulide to an amino group. Thi...
Sailleau C, Moulay S, Cruciere C, Laegreid WW, Zientara S.A reverse transcription-polymerase chain reaction (RT-PCR) assay followed by dot-blot hybridisation was used to detect African horse sickness virus (AHSV); the primers employed amplified the S7 gene that encodes the VP7 protein. The RT-PCR assay was compared with virus isolation for detecting AHSV in blood samples form horses experimentally infected with AHSV-4 and AHSV-9. The influence of sample storage and transportation and the effects of two anticoagulants (EDTA and heparin) were also studied. RT-PCR results were obtained within 48 hours as opposed to a minimum of 15 days for virus isolati...
Moore T, Wilcke J, Chilcoat C, Eyre P, Crisman M.Equine neutrophils (PMN) play a critical role in inflammatory processes in horses. The objective of this study was to characterize equine PMN function ex vivo following stimulation with calcium ionophore A23187 (A23187) and phorbol myristate acetate (PMA). These stimulants trigger different branches of the PMN activation process that occurs in vivo. Equine PMN were isolated from the whole blood of six clinically normal geldings using a one-step discontinuous Percoll gradient technique. Neutrophil aggregation, degranulation, and superoxide anion production were evaluated in assay systems which ...
Trim CM, Eaton SA, Parks AH.An 8-year-old Thoroughbred gelding with colic was anesthetized for surgical correction of right dorsal displacement of the ascending colon. Removal of the nasogastric tube at the end of surgery resulted in hemorrhage from the nares and loss of 24 L of blood. Treatment included administration of acetated Ringer's solution, hypertonic saline solution, and dobutamine. A blood transfusion was started after hemorrhage was controlled, and arterial pressure was restored to the prehemorrhage value, but was stopped after infusion of 2.7 L of blood because of a suspected adverse reaction. This case indi...
Persson SG.The purposes of this study were to elucidate the influences of age and sex on the heart rate (HR, bpm) and blood lactate (LA, mmol/l) related exercise tolerance parameters V2000 (tread ill velocity at HR 200), VLA4 (velocity at LA 4), W200 (power output at V2000), and WLA4 (power output at VLA4), and to establish reference values for these in normally performing Standardbred trotting race horses. A further aim was to improve the predictability of individual normal values by correlating them with the total red blood cell volume (CV) alone or in combination with the blood lactate response at V20...
Kumar S, Malhotra DV, Dhar S.The present study aimed to develop Dot-ELISA, complement fixation test (CFT) and capillary tube agglutination test (CAT) for serodiagnosis of Babesia equi infection and to compare their sensitivity with each other. For this study, sequential serum samples were collected from four donkeys experimentally infected with B. equi up to 90 days post infection (P.I.). B. equi antigen was prepared from the blood of a donkey showing more than 80% parasitaemia. Dot-ELISA, CF and CA tests were standardized as per the standard method. While performing CFT, it was observed that CFT standardized for the donk...
Fenger CK, Granstrom DE, Langemeier JL, Stamper S.To determine the clinical findings, course of treatment, and long-term outcome of horses on a farm in central Kentucky during an epizootic of equine protozoal myeloencephalitis (EPM). Methods: Cohort study. Methods: 21 horses on a farm in central Kentucky, 12 of which developed clinical signs of EPM. Methods: Horses on the farm were serially examined for signs of neurologic disease and serum and CSF antibodies to Sarcocystis neurona. Horses were considered to have EPM if they had neurologic signs and positive test results for antibodies to S neurona in CSF. Blood values were monitored for evid...
de Moura Alonso J, de Melo-Neto GB, Dos Santos B, Mogollón García HD, Paim KP, Pinheiro Ferreira JC, Santos Schmidt EM, da Silva ANF, da Cunha GM....This study aimed to evaluate the inflammatory response of miniature horses subjected to open and half-closed orchiectomy by physical examination, blood cell count, peritoneal fluid evaluation, total plasma protein, fibrinogen, and serum amyloid A (SAA) concentrations. Methods: Thirteen male healthy miniature horses were divided into two groups, according to the surgical approach: half-closed technique (HCT) and open technique (OT). The HCT group was subjected to ligation of the spermatic cord followed by its sharp incision, and closure of the vaginal tunic, and the OT group was only submitted ...
Rutkowski JA, Eades SC, Moore JN.A chronic model with an ultrasonic transit time blood flow probe and strain gauge force transducers implanted on the cecum was used to evaluate cecal mechanical activity and cecal arterial blood flow in 4 conscious adult horses. Intravenous administration of xylazine (1.1 mg/kg of body weight) significantly decreased heart rate and cardiac output, but significantly increased diastolic pulmonary arterial pressure, mean pulmonary arterial pressure, carotid arterial pressure, and central venous pressure. Lateral cecal arterial blood flow after xylazine administration was decreased substantially m...
Roneus B, Arnason T, Collinder E, Rasmussen M.A clinical material of 133 Standardbred horses with palmar/plantar osteochondral fragments (POF) in the metacarpo- and metatarsophalangeal joints were studied. All horses had their fragments removed with arthroscopic surgery. 102 of the horses were 3 years old or younger when surgery was performed. Anatomical localisations of the fragments were in agreement with earlier reports. There was no statistical significant difference in month of birth in the POF--group compared to the total population. Eighty % of the horses that had raced before surgery came back to racing. The racing performance rel...
Parry BW, Gay CC, McCarthy MA.Eighteen horses were used to investigate the influence of head position on arterial blood pressure, measured indirectly at the coccygeal artery. Head height significantly altered systolic pressure, diastolic pressure, pulse pressure, and mean arterial pressure, such that head-lowering decreased and head-raising increased all variables.
Weiss DJ, Evanson OA, Wells RE.To determine whether synthetic peptides containing the arginine-glycine-aspartate (RGD) sequence inhibit equine platelet function. Methods: For in vitro studies of blood, 3 healthy Thoroughbreds; for in vivo and ex vivo studies of administration of RGD-containing peptides, 4 young adult pony mares. Methods: Blood was incubated with and without addition of aspirin or RGD-containing peptides (RGDS, RPR 110885) and platelet aggregation responses and platelet adhesion to subendothelial collagen were determined. RPR 110885 was administered IV, and platelet function was evaluated. Platelet aggregati...
Patoux S, Istasse L.Eight trained horses (6 mares - 2 geldings, 6 Selle Français, 2 Trotteur Français, 12 ± 5.8 years old, 538 ± 72.5 kg) were offered three diets to potentially affect haematology and the fatty acids (FA) profiles in red blood cells (RBC) membranes. The control diet was composed of 50% hay and 50% concentrate containing mainly rolled barley (48%) and whole spelt (48%). In the case of sunflower oil diet, sunflower oil (62.0% of α-linoleic acid, LA) was incorporated at a rate of 8% and substituted by an equal proportion of barley. In the linseed oil diet, first cold-pressed linseed oil (...
Bostedt H, Hospes R, Herfen K.Basing on exact investigations of normal behaviour and abnormalities in newborn and up to 24 hours old foals a program for evaluation, comprehending exogeniously judgable criteria, was developed. It aims at a quick recognition of aberrations in behaviour. The program includes a score, which allows early diagnosis of even subtile abnormalities. As a result, a veterinary surgeon should be consulted if the score exposes a critical situation, so that therapy can be started in time. Furthermore informations about investigations on blood-glucose- and immunoglobulin-G-concentration in relation to neo...
Evans MJ, Loy RG, Taylor TB, Barrows SP.Cyclic mares were given daily i.m. injections of 150 mg progesterone (Group P, N = 4), 150 mg progesterone and 10 mg oestradiol-17 beta (Group PE, N = 3), 10 mg oestradiol-17 beta (Group E, N = 3) or cottonseed oil vehicle (Group C, N = 4), from the day after ovulation (Day 1) to Day 28. Blood samples were collected daily, and the ovaries were palpated every 1-2 days. Serum FSH and LH concentrations were measured in all samples, and means determined for 7 consecutive 4-day periods throughout treatment. Comparisons within each steroid treatment group between time periods and comparisons between...
The Journal of heredityJuly 1, 1987
Volume 78, Issue 4 248-250 doi: 10.1093/oxfordjournals.jhered.a110376
Bowling AT.Blood type analysis of 29 foals in a paternal half-sib family verified linkage of five LGII loci (Es, E, To, Gc, Al). Population and parentage data from other tobiano-spotted horses suggested conservation of a tightly linked (To:GcS:AlB) marker complex.
Critchley KL.A 6 month Welsh pony filly with an interventricular septal defect in conjunction with a pulmonary stenosis due to a bicuspid pulmonary valve is described. The animal had poor exercise tolerance, a loud pansystolic murmur and a precordial thrill. Blood pressure and oxygen tension values obtained during cardiac catheterization suggested the diagnosis which was confirmed at autopsy.
Manohar M, Goetz TE.It has been reported that pulmonary injury (i.e. capillary stress failure) evoked histamine release from airway inflammatory/mast cells contributes to exercise-induced arterial hypoxemia (EIAH) and that pre-exercise inhalation of nedocromil sodium mitigated EIAH in human subjects 'Med. Sci. Sports Exercise 29, (1997) 10-16'. Because exercise-induced pulmonary hemorrhage due to capillary stress failure is routinely observed in racehorses, we examined whether nedocromil inhalation would similarly benefit EIAH and desaturation of hemoglobin in horses. Two sets of experiments, namely, placebo stud...
Buschmann H, Baumann M.During strenuous exercise of horses that are prepared for international Three-Day-Events a significant decrease in the in vitro killing rate of phagocytosed yeast cells by the blood granulocytes has been observed. Other immunological parameters, such as the phorbolmyristate dependent chemiluminescence in granulocytes and the mitogenic stimulation of blood lymphocytes, remained unchanged.
Court MH, Engelking LR, Dodman NH, Anwer MS, Seeler DC, Clark M.The pharmacokinetics of dantrolene sodium were investigated in horses following both intravenous (2 mg/kg) and intragastric (4 mg/kg) administration. Two ponies also received dantrolene sodium intravenously (2 mg/kg) in a pilot study to obtain preliminary kinetic data and to determine urinary and biliary excretion of the intact drug. Distribution and elimination of dantrolene was rapid, resulting in an elimination half-life of 129 +/- 8 (SEM) min and a whole body clearance of 4.16 +/- 0.52 ml/min/kg. Following intragastric administration, dantrolene rapidly acheived peak concentrations within ...
Budnitskaya P, Gapanhuk E, Henriques OB.The kininogenase activity of trypsin, plasmin, plasma kallikrein and heated Bothrops venom was compared, using fresh, heated and heat-acid-denatured horse plasma as source of kininogen. The venom kininogenase was found to have the highest activity on fresh horse plasma, followed by plasmin and trypsin which were equally active, and plasma kallikrein which was half as active as plasmin on these substrates. Plasmin and trypsin released more kinin from heat-treated than from fresh plasma whereas kallikrein released half as much as it liberates from fresh plasma. On heat-aciddenatured plasma equal...
Todini L, Malfatti A.An instance of hormone assay method flaw is reported. In this journal Chronobiology International, two papers appeared in which an ELISA method for human serum or plasma was utilized for blood serum of horse and sheep, respectively. From our testing, it is resulted that such method does not work at all for equine, sheep and other animal species. The use of commercial hormone assay kits for heterologous species always needs a careful validation procedure. First, the same hormone molecule by different species could not share enough homology to be regognized by and react with antibodies utilized ...
Shih AC.Monitoring variables of cardiac performance in horses is challenging owing to patient size, temperament, and anatomic peculiarities. Blood pressure is a major determinant of afterload, but it is not a reliable surrogate of cardiac performance and tissue perfusion. Cardiac output, together with arterial and venous oxygen content, provides insight as to the adequacy of delivery of blood and oxygen to the body as a whole and can be used to gauge the fluid responsiveness and cardiovascular status of the patient. Measurement of intracardiac pressures serves to assess cardiac filling pressures, myoc...
Adeyefa CA.The rapid diagnosis of African horse sickness (AHS) during the incubation period using virus antigens in peripheral blood mononuclear cells (PBMC) and red blood cells (RBC) in a sandwich indirect enzyme-linked immunosorbent assay (ELISA) is reported. PMBC consistently gave higher positive ELISA results than RBC from blood collected during viraemia from clinically affected horses. The potential of the method described for wider application in rapid diagnosis and virus surveillance in susceptible equine populations, particularly in AHS-free and in enzootic areas, for effective control strategies...
Requena F, Campos MJAPM, Martínez Marín AL, Camacho R, Giráldez-Pérez RM, Agüera EI.In equine reproduction, accurate and timely detection of the moment of ovulation is of great importance. Power Doppler ultrasound technology is a non-invasive method that enables to assess the morpho-echogenic features and blood flow changes during the estral cycle in mares. The objective of the present study was to evaluate the influence of age on ultrasonographic parameters (follicular diameter, follicular blood flow-FBF, corpus luteum (CL) area and corpus luteum blood flow-CLBF) and blood plasma progesterone concentrations in cycling Spanish Purebred mares (15 less than 8 years old and 15 e...
Kollias-Baker C, Sams R.The objective of this study was to determine if the administration of poppy seeds to horses would result in detectable concentrations of morphine in urine and blood samples, as has been shown to occur in humans. In this study blood and urine samples were collected following administration of poppy seeds and morphine sulfate orally to four horses. Urine samples were subjected to enzyme-linked immunosorbent assay (ELISA) for the presence of morphine. All urine samples testing positive by ELISA, as well as plasma samples collected after administration of the 10-g doses of poppy seeds, were analyz...
Ratzlaff MH, Shindell RM, DeBowes RM.Blood pressures from the catheterized lateral digital vein of the fore-limbs of 6 clinically normal horses were measured at rest, at the walk, and at the trot. Digital venous pressures were compared with the phases of the stride and weight-bearing forces, using electrogoniometry and a force platform. Rapid increases in digital venous pressures to maximal values were observed immediately before maximal forces during the support period of the stride. At the trot, increases in peak vertical forces were paralleled by increases in peak digital venous pressures. Seemingly, the hydrodynamics of the d...
Lowry TF, Forster HV, Korducki MJ, Forster AL, Forster MA.To gain insight into central and peripheral contributions to changes in breathing during hypoxia, we compared effects on breathing of reducing inspired PO2 (hypoxic hypoxia) with reducing arterial O2 content (CaO2) through elevation of carboxy-hemoglobin (COHb) (CO hypoxia). Twelve awake ponies were studied during 1 h of breathing room air followed by 6 h when COHb was increased to 25% and CaO2 was decreased by 17%. When COHb was increased, arterial PCO2 (PaCO2) increased gradually to 1.3 Torr above (P < 0.05) control level between 30 and 45 min of CO exposure. Pulmonary ventilation (VE) de...
Forster HV, Murphy CL, Brice AG, Pan LG, Lowry TF.The major objective was to determine in ponies whether factors in addition to changes in blood PCO2 contribute to changes in plasma [H+] during submaximal exercise. Measurements were made to establish in vivo plasma [H+] at rest and during submaximal exercise, and CO2 titration of blood was completed for both in vitro and acute in vivo conditions. In 19 ponies arterial plasma [H+] was decreased from rest 4.5 neq/l (P less than 0.05) during the 7th min of treadmill running at 6 mph, 5% grade (P less than 0.5). A 5.6-Torr exercise hypocapnia accounted for approximately 2.9 neq/l of this reduced ...
Pereira MR, Trein CR, Webster A, Dallagnol B, Gonchoroski GZ, Pellegrini DP, Doyle R, Klafke G, Reck J.The apicomplexan hemoprotozoan Theileria equi is a tick-borne pathogen that causes disease in equids, and together with Babesia caballi, causes equine piroplasmosis (EP). Many ticks are associated with EP around the world, and in South America three species may be related: Dermacentor nitens, Amblyomma sculptum, and Rhipicephalus microplus, as they are commonly found in horses. Among the species cited above, only R. microplus is found in Rio Grande do Sul state, Southern Brazil. In addition, this state has the only area legally free of R. microplus in Brazil. This study aimed to compare the se...
Akens MK, Holznagel E, Franchini M, Bracher V.In the present study, two methods of lymphocyte preparation, whole blood lysis and Ficoll-Paque separation, prior to FACS analysis were compared. The comparison was done with single and dual-colour staining techniques. Monoclonal antibodies (mAb) against eCD4, eCD5, eCD8 and eMHC class II were used. There was no significant difference in the results obtained by these two methods.
Stick JA, Arden WA, Chou CC, Parks AH, Wagner MA, Johnston CC.Using isolated autoperfused intestinal segments, the effects of flunixin meglumine administration on systemic arterial blood pressure, jejunal blood flow, vascular resistance, motility, arteriovenous oxygen difference, and oxygen consumption were determined in 10 anesthetized ponies ventilated with a mixture of halothane and oxygen. Saline solution or flunixin meglumine (1.1 mg/kg of body weight) was infused as a single bolus into the left jugular vein. By 10 minutes, flunixin meglumine increased systemic arterial blood pressure and increased intestinal vascular resistance. The jejunal blood f...
Gillespie JR.Respiratory function in newborn foals is discussed with particular reference to the important part played by functional residual capacity and chest wall compliance in maintaining blood gaseous exchange within normal limits.
Gürtler LG, Yeboa DA, Cleve H.The membrane components of equine, porcine and ovine erythrocytes were separated by sodium dodecylsulfate polyacrylamide gel electrophoresis and subsequently incubated with the radioiodinated lectins from lentils (LCH), castorbeans (RCA), Phaseolus beans (L-PHA), gorse seeds (UEH-F) and from vineyard snails (HPA). The following individual glycoproteins could be labeled: gp 26, 33, 100 and 320 in horse erythrocytes, gp 24, 46, 75, 130 and 210 in swine and gp 24, 57, 100 and 210 in sheep erythrocytes.
Smith JE, Agar NS.Anaemic horses do not provide reticulocytes during an erythropietic response. Acute blood loss was studied in 4 ponies as a model to monitor changes in erythrocyte metabolism during active erythropoiesis. Following phlebotomy, erythrocyte adenosine-5-triphosphate, adenosine-5-diphosphate, glucose-6-phosphate, fructose-6-phosphate, and phosphoenolpyruvate increased signifcantly. The remaining glycolytic intermediates did not change. It is suggested that the determination of erythrocyte adenosine-5-triphosphate may be used to evaluate erythrocyte response following acute blood loss in the horse....
Taylor PM.Some metabolic and endocrine effects of hypoxaemia were studied during halothane anaesthesia in six ponies. Each was anaesthetised twice; on one occasion a 20-minute period of hypoxaemia (arterial oxygen tension between 4.4 and 5.8 [mean 5.3] kPa) was imposed during 120 minutes of anaesthesia. On the second occasion arterial oxygen tension was maintained above 17 kPa throughout. Routine cardiovascular monitoring was performed and blood samples were taken to measure haematocrit, cortisol, insulin, glucose and lactate. Anaesthesia was associated with hypotension in both groups (mean ABP 7.0 kPa...
