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.
Fazio E, Medica P, Trifiletti C, Ferlazzo A.The objective of this study was to compare in detail the total and free iodothyronines' pattern of mares from the first ovulation of the year over an extended period of 12 weeks. A total of 20 mares were used in the study. The mares were classified into two groups: mares mated at the ovulation (n = 10) used as observational group and mares unmated at the ovulation (n = 10) used as control group. Serum total and free triiodothyronine (T3, fT3) and thyroxine (T4, fT4) levels were measured in baseline conditions at the first ovulation of year and once a week until 12 weeks later. For the experi...
Holcombe SJ, Jacobs CC, Cook VL, Gandy JC, Hauptman JG, Sordillo LM.Endotoxemia models are used to study mechanisms and treatments of early sepsis. Repeated endotoxin exposures induce periods of endotoxin tolerance, characterized by diminished proinflammatory responses to lipopolysaccharide (LPS) and modulated production of proinflammatory cytokines. Repeated measure designs using equine endotoxemia models are rarely performed, despite the advantages associated with reduced variability, because the altered responsiveness would confound study results and because the duration of equine endotoxin tolerance is unknown. We determined the interval of endotoxin toler...
Azarpeykan S, Dittmer KE, Gee EK, Marshall JC, Wallace J, Elder P, Acke E, Thompson KG.The aims of the study were to determine the effect of season and blanketing on vitamin D synthesis in horses and examine the interaction between vitamin D and other analytes involved in calcium homeostasis. Twenty-one healthy horses at pasture were included; 5 were covered with standard horse blankets including neck rugs. Blood samples were collected for 13 mo and analyzed for 25-hydroxyvitamin D2 (25OHD2) and 25-hydroxyvitamin D3 (25OHD3), 1,25-dihydroxyvitamin D (1,25[OH]2D), ionized calcium (iCa), total calcium (tCa), phosphorus (P), total magnesium (tMg), and parathyroid hormone (PTH). Gr...
McElhone RL, Meakin GE, French JC, Alexander T, Morgan RM.A study was designed to investigate the effects of external variables, including blood type, flooring surface, footwear tread depth and blood dryness, on the appearance of blood-based footwear marks, with particular reference to simulating a specific casework scenario. Results showed that footwear marks left in human blood tended to be of greater quality than those in equine blood, highlighting a potential issue in applying data generated with equine blood to human bloodstains in casework. Footwear tread effects were also dependent on blood type, but the type of flooring surface did not affect...
Arfuso F, Quartuccio M, Bazzano M, Fazio F, Piccione G.Knowledge of hematologic function in postparturient mares and foals is crucial for the monitoring of their health status and for the prompt diagnosis of pathologic conditions. Objective: The aim of this study was to evaluate erythrocyte osmotic fragility (EOF) and select hematologic variables in mares and their foals during the first month after foaling. Methods: Blood samples were collected from each animal every 3 days from day 1 until day 30 after foaling, and tested for RBC count, HGB, HCT, MCV, and EOF. Two-way repeated measures analysis of variance (ANOVA) and Bonferroni post hoc compari...
Van de Water E, Oosterlinck M, Duchateau L, Pille F.The purpose of this study was to determine whether the scil Vet abc Plus(+) (SCIL Animal Care Company, Altorf, France), an impedance hematology analyzer, can accurately quantify and differentiate nucleated blood cells (NBCs) in equine synovial fluid. Synovial fluid samples (n=242) in different stages of experimentally induced inflammation were analyzed with and without hyaluronidase pretreatment and compared to manual hemocytometer counts and smear reviews. No significant effect of hyaluronidase pretreatment was observed. Total nucleated cell counts of the scil Vet abc Plus(+) were significant...
Mach N, Plancade S, Pacholewska A, Lecardonnel J, Rivière J, Moroldo M, Vaiman A, Morgenthaler C, Beinat M, Nevot A, Robert C, Barrey E.The adaptive response to extreme endurance exercise might involve transcriptional and translational regulation by microRNAs (miRNAs). Therefore, the objective of the present study was to perform an integrated analysis of the blood transcriptome and miRNome (using microarrays) in the horse before and after a 160 km endurance competition. A total of 2,453 differentially expressed genes and 167 differentially expressed microRNAs were identified when comparing pre- and post-ride samples. We used a hypergeometric test and its generalization to gain a better understanding of the biological functio...
Canisso IF, Ball BA, Esteller-Vico A, Williams NM, Squires EL, Troedsson MH.While advanced stages of ascending placentitis can be diagnosed by transrectal ultrasonography and clinical signs, early stages can be missed. Thus, additional tools could enhance assessment of placental health. Objective: To characterise peripheral dehydroepiandrosterone sulphate (DHEA-S) and testosterone concentrations in mares carrying normal pregnancies (Study 1) and compare plasma concentrations of DHEA-S, testosterone, oestradiol 17-β (oestradiol) and oestrone sulphate (OES) in mares with or without placentitis (Study 2). Methods: Longitudinal cohort study of healthy mares (Study 1) and...
Salz RO, Ahern BJ, Boston R, Begg LM.To determine the variation of tracheal mucus scores, tracheal blood scores and transendoscopic tracheal wash (TW) cytology in a population of Thoroughbred (TB) racehorses and assess their association with racing performance. Methods: A total of 220 endoscopic examinations were performed and TWs obtained from 155 TB racehorses. Samples were collected 60-120 min following gallop work. Tracheal mucus score, tracheal blood score and TW cytology were analysed and their association with racing performance assessed. Results: Of the total examinations and samples, 194 from 135 horses fitted the criter...
Liu Q, Meli ML, Zhang Y, Meili T, Stirn M, Riond B, Weibel B, Hofmann-Lehmann R.A reverse line blot (RLB) hybridization assay was adapted and applied for equine blood samples collected at the animal hospital of the University of Zurich to determine the presence of piroplasms in horses in Switzerland. A total of 100 equine blood samples were included in the study. The V4 hypervariable region of the 18S rRNA gene was amplified by polymerase chain reaction and analyzed using the RLB assay. Samples from seven horses hybridized to a Theileria/Babesia genus-specific and a Theileria genus-specific probe. Of these, two hybridized also to the Theileria equi-specific probe. The oth...
Carslake H, Karikoski N, Pinchbeck G, McGowan C.Serum insulin concentration is commonly measured during investigation of suspected endocrinopathic disease in horses, but immediate analysis is frequently unavailable. The aim of this study was to examine the effect of storing samples at room temperature for 72 h as serum and as whole blood, compared to immediate separation and freezing. Samples from 14 horses were evaluated. Correlation was excellent for all comparisons (≥0.992). Bland-Altman plots revealed a negative bias (mean difference 2.16 µIU/mL) in samples stored as whole blood compared to serum, but this difference was not cons...
Taylor AH, Seymour CJ.Horses may become hypoxaemic during anaesthesia despite a high inspired oxygen fraction (FiO2). A lower FiO2 is used commonly in human beings to minimise atelectasis and to improve lung function, and previously has been shown to be of potential benefit in horses in experimental conditions. Other studies suggest no benefit to using a FiO2 of 0.5 during clinically relevant conditions; however, low FiO2 (0.65) is commonly used in practice and in a large number of studies. The present study was performed to compare the effect of a commonly used FiO2 of 0.65 versus 0.90 on calculated respiratory in...
Assenza A, Casella S, Giannetto C, Fazio F, Tosto F, Piccione G.The aim of this study was to evaluate the modifications of some haematological parameters and iron profile during an 80-day training program and their relationship with athletic performance of performance horses. Methods: During the training period, 20 Thoroughbreds were subjected to a standardised exercise test, previously standardised for gallopers to evaluate athletic performance. The test was performed immediately before the beginning of the training program (T0) and after 30 days (T30), 60 days (T60) and 90 days (T90). For each horse, their velocities at blood lactate concentrations of 2 ...
de Vries A, Pakkanen SA, Raekallio MR, Ekiri A, Scheinin M, Taylor PM, Vainio OM.To investigate the effects of MK-467 on sedation quality, and cardiopulmonary and pharmacokinetic variables in horses sedated intravenously (IV) with romifidine. Methods: Experimental, randomized, crossover design. Methods: Seven healthy mares. Methods: Romifidine (80 μg kg-1 ; R) and MK-467 (200 μg kg-1 ; MK) were administered IV alone and in combination (R + MK). Levels of sedation and borborygmi were scored. Heart rate (HR), direct arterial blood pressure (ABP) and respiratory rate (fR ) were recorded. Arterial and venous blood gas analyses were performed and venous plasma drug conc...
Diel de Amorim M, Nielsen K, Cruz RK, Card C.Intrauterine plant oil infusion, including fractionated coconut oil, has been previously found to be a safe, inexpensive, and reversible method of prolonging the luteal phase in mares when administered on Day 10 of the estrous cycle. Our objective was to understand the uteroovarian response to the administration of fractionated coconut oil infusion in the uterus of diestrous mares. We hypothesized that intrauterine coconut oil administration on Day 10 would prolong luteal life span in a dose-dependent fashion and would result in higher serum progesterone levels than untreated mares at the expe...
McKeever KH, McNally BA, Hinchcliff KW, Lehnhard RA, Poole DC.To test the hypotheses that erythropoietin (rhuEPO) treatment increases systemic hematocrit, maximal O2 uptake (VO2max, by elevated perfusive and diffusive O2 conductances) and performance five female horses (4-13 years) received 15 IU/kg rhuEPO (erythropoietin) three times per week for three weeks. These horses had been splenectomized over 1 year previously to avoid confounding effects from the mobilization of splenic red blood cell reserves. Each horse performed three maximal exercise tests (one per month) on an inclined (4°) treadmill to the limit of tolerance; two control trials and one f...
Fazio E, Medica P, Cravana C, Bruschetta G, Ferlazzo A.The purpose of this study was to determine which physiological seasonal thyroid and lipid panel (triglyceride, [TG], total cholesterol, [tCho], high-density lipoprotein cholesterol, [HDL Cho], LDL cholesterol, phospholipids, [PDs]) changes occur in 12 Thoroughbred pregnant and six nonpregnant mares over a period of 12 months, from April to March, by into account the lactation stage. Serum total triiodothyronine (T3) and thyroxine (T4) levels were measured using immunoenzymatic assay kits; the serum lipid panel was analyzed using the enzymatic colorimetric method. One-way ANOVA reported a sign...
Sanchez-Teran AF, Bracamonte JL, Hendrick S, Burguess HJ, Duke-Novakovski T, Schott M, Hoff B, Rubio-Martínez LM.To evaluate the effect of arthroscopic lavage on systemic serum amyloid A (SAA) and SAA, total protein, nucleated cell count, and percentage of neutrophils in synovial fluid in healthy horses. Methods: Prospective experimental study. Methods: Healthy adult horses (n = 6). Methods: Middle carpal joints were randomly assigned to 1 of 2 treatments: arthrocentesis (controls) or arthroscopic lavage, with 30 day washout period between treatments. Synovial fluid and blood samples were collected at 0, 24, 48, 72, 96, and 120 hours. Measurements included systemic and synovial fluid SAA, as well as ...
Brøkner C, Austbø D, Næsset JA, Blache D, Bach Knudsen KE, Tauson AH.The hypothesis for this study was that a higher dietary proportion of soluble fibre would result in stable and constant plasma metabolite and regulatory hormone concentrations. The study was a 4×4 Latin Square design with a sequence of 17 days adaptation to the ration followed by 8 sampling days. The feed rations consisted of only timothy hay (H), hay plus molassed sugar beet pulp combined with either whole oats (OB) or barley (BB) and hay plus a loose chaff-based concentrate (M). Four horses were fitted with permanent caecal cannulas and liquid caecal content was withdrawn manually and blood...
Sanchez-Teran AF, Bracamonte JL, Hendrick S, Riddell L, Musil K, Hoff B, Rubio-Martínez LM.The objective of this study was to evaluate the effect of through-and-through joint lavage on systemic and synovial serum amyloid A (SAA), total protein, nucleated cell count and percentage of neutrophils in the synovial fluid of six healthy horses. A prospective experimental study was performed where one healthy tarsocrural joint of each horse was randomly assigned to receive repeated through-and-through joint lavage at 0, 48 and 96 h. Synovial fluid and blood samples were collected at 0 (baseline), 24, 48, 72, 96 and 120 h. Systemic and synovial SAA, total protein, nucleated cell count a...
Cervantes DT, Ball JM, Edwards J, Payne S.Equine infectious anemia virus (EIAV) causes lifelong infections ranging from acutely fatal, to chronic, to asymptomatic. Within infected animals, EIAV is found as a quasispecies. Many experimental studies on EIAV, carried out in the U.S. over the past 70 years, have used either the highly virulent Wyoming (EIAVWYO) field strain or various derivatives of that strain. These infections have provided insights into the variety of genetic changes that accumulate in the env gene and LTR in experimentally infected horses. In the current study, we obtained EIAV sequences from blood samples collected f...
Lee S, Hwang S, Yu HJ, Oh D, Choi YJ, Kim MC, Kim Y, Ryu DY.MicroRNAs (miRNAs) in blood plasma are stable under high levels of ribonuclease activity and could function in tissue-to-tissue communication, suggesting that they may have distinctive structural characteristics compared with non-circulating miRNAs. In this study, the expression of miRNAs in horse plasma and their characteristic nucleotide composition were examined and compared with non-plasma miRNAs. Highly expressed plasma miRNA species were not part of the abundant group of miRNAs in non-plasma tissues, except for the eca-let-7 family. eca-miR-486-5p, -92a, and -21 were among the most abund...
van Oostrom H, Schaap MW, van Loon JP.Hypoventilation or apnoea, caused by the induction of general anaesthesia, may cause hypoxaemia. Preoxygenation may lengthen the period before this happens. No scientific studies are published on preoxygenation in equine anaesthesia. Objective: To determine whether supplementation of oxygen at a flow rate of 15 l/min for 3 min via a nasal cannula before induction of general anaesthesia is effective in elevating the arterial partial pressure of oxygen (PaO ) directly after induction. Methods: Randomised, prospective clinical trial. Methods: A total of 18 American Society of Anesthesiologists ph...
Viu J, Armengou L, Ríos J, Cesarini C, Jose-Cunilleras E.Acid-base imbalances observed in human paediatric patients are associated with outcome. Likewise, neonatal foals may have different acid-base imbalances associated with diagnosis or prognosis. Objective: To determine acid-base imbalances by the quantitative method in ill neonatal foals and assess their association with diagnosis and prognosis. Methods: Observational prospective clinical study. Methods: This study included 65 ill neonatal foals (32 septic, 33 nonseptic) admitted to an equine referral hospital from 2005 to 2011with acid-base parameters determined on admission and a control group...
Woodman J, Wagg CR, Boysen SR, Leguillette R, Mizen K, Roy MF.Dexamethasone was administered to healthy horses daily for 7 days. Blood samples were collected at 3 time points from both treatment and non-treatment groups, and analyzed via thromboelastography (TEG). There were no significant differences in TEG parameters between treated and untreated horses, or within treatment groups over time. La dexaméthasone a été administrée à des chevaux en santé pendant 7 jours. Des échantillons de sang ont été prélevés à trois moments auprès des groupes de traitement et des groupes sans traitement et ensuite analysés par thrombo-élastographie (TEG)....
Romão FT, Pereira PF, Flaiban KK, Dearo AC, Fernandes TM, Lisbôa JA.Treatment of metabolic acidosis using sodium bicarbonate solutions is safe when blood gas analysis is available. The evidence that solutions containing metabolisable buffers can be used as an alternative for treatment of metabolic acidosis in horses is of practical interest. Objective: To investigate the safety and efficacy of a polyionic solution containing 84 mEq/l of lactate (L84) for the correction of induced hyperchloraemic metabolic acidosis. Methods: Non-randomised crossover design. Methods: Five healthy, adult, crossbred horses were used. A solution containing 100 mmol/l of HCl was inf...
Piccione G, Rizzo M, Arfuso F, Giannetto C, Di Pietro S, Bazzano M, Quartuccio M.During early post-partum period both neonatal foals and peripartum mares are most susceptible to diseases. The aim of this study was to establish physiologic modifications of leukogram during the first month after foaling in mares and their newborn foals. To this end blood samples were collected from nine mares and nine foals (T0-T10), every three days from the 1st day until the 30th day after foaling. Samples were analysed for white blood cell (WBC) count and differential leucocyte counts. Two-way repeated measure analysis of variance (ANOVA) showed, in postpartum mares WBC showed significant...
Arfuso F, Giannetto C, Giudice E, Fazio F, Piccione G.The effect of exercise on platelet aggregation, albumin and nonesterified fatty acids (NEFAs) values and the correlation among these parameters were evaluated in ten clinically healthy and regularly trained Thoroughbred horses. All horses were subjected to two simulated races. Blood samples were collected by jugular venipuncture before and after the first simulated race (T0PRE and T0POST), every 7 days at rest condition for a month (T1R-T2R-T3R), and before and after the second simulated race (T4PRE and T4POST) in order to assess platelet aggregation, albumin and nonesterified fatty acids (NEF...
Issel CJ, Foil LD.There is no credible evidence that the lentivirus that causes equine infectious anaemia (EIA) replicates in invertebrates. The virus persistently infects its equid hosts and is often present in blood in significant quantities. Blood-feeding arthropods thus have the potential to transfer the virus between hosts, especially if their feeding on the first host is interrupted and immediately continued on a second host. The general details and dynamics of mechanical transmission are included in this paper, as this agent presents an excellent model. Mechanical transmission can be effectively controll...
Mudge MC, Walker NJ, Borjesson DL, Librach F, Johns JL, Owens SD.Post-transfusion survival of allogeneic RBCs has been reported to be much shorter in horses than in other species. We hypothesized that post-transfusion survival of biotinylated allogeneic equine RBCs would be greater than the survival previously reported from studies using radioactive RBC-labeling techniques. Objective: The study objective was to determine post-transfusion survival of N-hydroxysuccinimide (NHS)-biotin-labeled allogeneic equine RBCs transfused into adult horses. Methods: Horses were adults and included 5 donors and 5 recipients. All horses were blood-typed, and donors were pai...
Zhang Y, Chahan B, Liu S, Song R, Li Y, Huercha , Guo Q, Wu H, Zhu Y.In order to found the epidemiological situation of T. equi in the horse herds in Ili Prefecture of Xinjiang Province, 723 blood samples collected from 4 counties and districts were test for T. equi through microscopic detection and Polymerase chain Reaction (PCR). In the result, we found that the 295 of 723 blood samples (40.8%) were positive for T. equi infection. The results showed that the choosed counties have a varying degrees infection. To our knowledge, this is the first time that we detected T. equi infection using the molecular techniques from Ili in Xinjiang Uygur Autonomous region.
Kaabia Z, Dervilly-Pinel G, Popot MA, Bailly-Chouriberry L, Plou P, Bonnaire Y, Le Bizec B.Nandrolone (17β-hydroxy-4-estren-3-one) is amongst the most misused endogenous steroid hormones in entire male horses. The detection of such a substance is challenging with regard to its endogenous presence. The current international threshold level for nandrolone misuse is based on the urinary concentration ratio of 5α-estrane-3β,17α-diol (EAD) to 5(10)-estrene-3β,17α-diol (EED). This ratio, however, can be influenced by a number of factors due to existing intra- and inter-variability standing, respectively, for the variation occurring in endogenous steroids concentration levels in a si...
Rüegg SR, Torgerson PR, Doherr MG, Deplazes P, Böse R, Robert N, Walzer C.Piroplasmosis has been identified as a possible cause of mortality in reintroduced Przewalski's horses (Equus ferus przewalskii) in the Dsungarian Gobi (Mongolia). A cross-sectional and a longitudinal study were conducted in a representative sample (n = 141) of the resident domestic horse population and in 23 Przewalski's horses to assess the prevalence of Theileria equi and Babesia caballi. Piroplasms were detected in blood by light microscopy in 6.7% (95% confidence interval [CI]: 3.6-12.2%) of the domestic horse samples. Antibody prevalence was 88.6% (95% CI: 82.4-92.9%) for T. equi and 75....
Turlo A, Cywinska A, Czopowicz M, Witkowski L, Szarska E, Winnicka A.The aim of this study was to evaluate serum amyloid A (SAA) concentration in horses with orthopedic injuries acquired during racing and in healthy ones after completing the race. Injuries of bone and tendon did not cause radical increase in SAA concentration observed in other inflammatory conditions. SAA concentration correlated positively with white blood cell count (WBC) on the 3rd-4th days after race being significantly higher in the injured horses than in the control group in that time. It was suggested that racing effort may cause increase in SAA level, more pronounced in horses manifesti...
Weiss DJ, McClay CB, Smith CM, Rao GH, White JG.Platelet function was evaluated in horses with exercise-induced pulmonary hemorrhage (bleeder) and in control horses (nonbleeder). Platelet aggregation, secretion, and adhesion to rabbit aortic subendothelium were similar for bleeders and nonbleeders. Platelets readily aggregated in response to ADP, thrombin, collagen, and arachidonic acid, but platelet secretion occurred only with high concentrations of thrombin. Platelets readily adhered to rabbit aortic subendothelium and tended to form large thrombi rather than platelet monolayers or aggregates. These data suggest that horses may be predis...
Brunner J, Wichert B, Burger D, von Peinen K, Liesegang A.This study aims at the comparison of the actual feeding of horses with the recommendations from the literature, and it studies the effects of feeding and exercise on several blood metabolic parameters before and after exercise. Blood samples were collected from 25 horses during one-star eventing competitions and evaluated for blood glucose, insulin, lactate, free fatty acids and triglyceride levels. Questionnaires on the feeding practices of the horses were evaluated. The questionnaires revealed that during training, and on tournament days, horses received on average 4.3 kg of concentrate per ...
Tennent-Brown B.Although a range of plasma-based products (e.g., cryoprecipitate, albumin, platelet-rich plasma, individual coagulation factors) are available to human physicians, equine veterinarians are largely restricted to using whole blood, frozen plasma, and fresh frozen plasma for transfusions. The indications for frozen or fresh frozen plasma in human medicine are relatively limited, and there is little evidence supporting the efficacy of these products in many cases. Furthermore, many human physicians have concerns regarding disease transmission and anaphylactic reactions after administration of any ...
Ginther OJ, Utt MD, Beg MA.The temporal relationships between follicle deviation and systemic hormone concentrations were studied in mares. Blood samples were obtained at 01:00, 07:00, 13:00, and 19:00 h from nine mares throughout an interovulatory interval. Diurnal variation in progesterone occurred on Days 4-12 and in LH on Days 4 and 5; the lowest concentration for both hormones was at 13:00 h. Ultrasonically observed deviation in the ovulatory follicular wave began on Day 15.7+/-0.5 (ovulation=Day 0). An increase (P<0.002) in LH began on Day 14 before the beginning of deviation, and an increase (P<0.05) in est...
Young LE, Blissitt KJ, Bartram DH, Clutton RE, Molony V, Jones RS.In order to determine if transoesophageal Doppler echocardiography could be used to estimate cardiac output in anaesthetized horses, we have compared the technique with estimations of cardiac output by thermodilution in eight healthy adult thoroughbreds. Measurements of aortic blood flow velocity were made by high pulse repetition frequency (HPRF) and continuous wave (CW) Doppler echocardiography from a 3.5-MHz transoesophageal probe. Cardiac output was increased during the study by administration of dobutamine, providing a range of cardiac output measurements by thermodilution from 15.0 to 64...
Suagee JK, Burk AO, Quinn RW, Hartsock TG, Douglass LW.Low-grade inflammation precedes the development of obesity-related metabolic disorders in humans, but whether the same is true in the horse is not known. The objective of this study was to examine the effects of weight gain and diet on the inflammatory state of horses as determined by serum concentrations of tumour necrosis factor-α (TNF), an inflammatory cytokine. Fifteen mature Thoroughbred geldings with an initial body weight (BW) of 519±12 kg and body condition score (BCS) of 4.3±0.1 were fed a diet of hay plus a concentrate that was either high in non-structural carbohydrates (NSC) (i....
Hamblin C, Anderson EC, Mellor PS, Graham SD, Mertens PP, Burroughs JN.Four ponies were each inoculated with a different serotype of African horse sickness virus (AHSV) which had been passaged through cell culture in order to achieve attenuation. Three of the ponies died suddenly after showing mild clinical signs, the fourth pony remained clinically normal and was killed at day 38. Infectious AHSV was isolated from blood samples collected at intervals from all four ponies. Positive antigen ELISA reactions were only observed with blood samples from two of the ponies on the two days preceding death. Specific AHSV antibodies were detected by ELISA in serum samples f...
DeNotta SL, Brooks MB.Horses with clinical signs of unprovoked or excessive hemorrhage should be evaluated for underlying platelet defects or coagulopathies. This article provides an overview of preliminary screening and definitive tests to assess coagulation and identify hemostatic defects in horses, as well as a review of the hemostatic disorders most frequently encountered in clinical practice.
Thane K, Bedenice D, Pacheco A.To determine the extent of intraoperator (between duplicate samples) and interoperator (between different operators) variability in equine thromboelastography (TEG). Methods: Kaolin-activated TEG was performed in duplicate by operator-pair A/B or A/C (2 groups of 10 horses) using discrete setups, within 30-45 minutes of vacuum-assisted blood collection. Recorded TEG variables included clot initiation time (R), clot formation time (K), rate of clot formation (α), clot strength (MA), and viscoelastic/shear strength (G). Operators independently determined the clinical coagulation status for each...
Dunkle NJ, Bottoms GD, Fessler JF, Knox K, Roesel OF.A study was conducted to determine whether body fluids undergo a net shift from one compartment to another during endotoxin-induced shock in the pony, and whether flunixin meglumine alters these endotoxin-induced changes in the volumes of body fluid compartments. Total blood, RBC, and plasma volumes were determined, using 51Cr-labeled RBC and PCV that were corrected for trapped plasma. Total body water was measured by distribution of 3HOH. Arterial blood pressure was measured directly, using a blood pressure transducer. Treatment (flunixin meglumine, 1.1 mg/kg of body weight) was given to 6 of...
Studdert MJ, Azuolas JK, Vasey JR, Hall RA, Ficorilli N, Huang JA.To develop and validate specific, sensitive and rapid diagnostic tests using RT-PCR for the detection of Ross River virus (RRV), Kunjin virus (KV) and Murray Valley encephalitis virus (MVEV) infections in horses. Methods: Primer sets based on nucleotide sequence encoding the envelope glycoprotein E2 of RRV and on the nonstructural protein 5 (NS5) of KV and MVEV were designed and used in single round PCRs to test for the respective viruses in infected cell cultures and, in the case of RRV, in samples of horse blood and synovial fluid. Results: The primer pairs designed for each of the three vir...
Brummer M, Hayes S, Adams AA, Horohov DW, Dawson KA, Lawrence LM.Selenium status has been reported to affect immune function across many different species. Yet few studies have focused on the effect of Se status on the equine immune system. This study examined the effect of Se supplementation on vaccination response and immune function in mature horses. Twenty-eight horses were blocked by age and sex and were randomly allocated to 1 of 4 dietary treatment groups: low Se (LS), adequate Se (AS), Se-yeast (SP), and sodium selenite (SS). For 35 wk, horses allocated to LS, SP, and SS received a low-Se diet (0.06 mg/kg DM) with the intention to lower Se stores, w...
Persson SG, Funkquist P, Nyman G.The purposes of this study were to elucidate the influences of age and sex on the mass specific blood volume parameters: total blood volume (TBV/BW, ml/kg), plasma volume (PV/ BW, ml/kg), total red cell volume (CV/BW, ml/kg) and maximal packed cell volume (PCV, l/l, i.e. after total mobilisation of the splenic red cell reservoir) and to establish reference values for these in normally performing Standardbred trotting race horses. In total 205 horses were studied. They were all, according to their owners and/or trainers, performing satisfactorily in racing or training for shortly impending raci...
Palazzo M, Vizzarri F, Cinone M, D'Alessandro AG, Martemucci G, Casamassima D.The effect of Lippia citriodora extract on selected blood parameters and on plasma oxidative markers in Avelignese horses was evaluated. Twenty-four horses were divided into three groups, consisting of eight animals each. Results of two experimental groups, 0.5 mg of verbascoside per kg of metabolic body weight (bw ) in the low-dose group (LVB) and 1.0 mg of verbascoside per kg of metabolic body weight (bw ) in the high-dose group (HVB), were compared to the control group (CON). Groups fed L. citriodora extract (HVB and LVB) showed a significant decrease in triglycerides, total cholesterol ...
Piccione G, Bertolucci C, Grasso F, Guidice E.The effect of storage temperature and time on blood gas and acid-base values has been investigated intensively in cattle and dogs; however, data are lacking in other species. Objective: The aim of our study was to evaluate changes in gas composition and acid-base values in venous blood stored at different temperatures and for different times in 4 domestic species in Italy. Methods: Blood samples from Comisana sheep (n = 10), Maltese goats (n = 10), Ragusana donkeys (n = 10), and Thoroughbred horses (n = 10) were analyzed after storage at 23 degrees C (room temperature) for 15 minutes (group I)...
Manohar M, Goetz TE, Hassan AS.Strenuously exercising horses exhibit arterial hypoxemia and exercise-induced pulmonary hemorrhage (EIPH), the latter resulting from stress failure of pulmonary capillaries. The present study was carried out to examine whether the structural changes in the blood-gas barrier caused by a prior bout of high-intensity short-term exercise capable of inducing EIPH would affect the arterial hypoxemia induced during a successive bout of exercise performed at the same workload. Two sets of experiments, double- and single-exercise-bout experiments, were carried out on seven healthy, sound Thoroughbred h...
Thorsteinsdóttir L, Jónsdóttir S, Stefánsdóttir SB, Andrésdóttir V, Wagner B, Marti E, Torsteinsdóttir S, Svansson V.Two types of gammaherpesviruses (γEHV) are known to infect horses, EHV-2 and EHV-5. Foals become infected early in life, probably via the upper respiratory tract, despite maternal antibodies. In this study, we analyzed samples from a herd of mares and their foals. The foals were followed from birth to 22 months of age and the dams during the first 6 months postpartum. Blood and nasal swab samples were taken regularly for evaluation of antibody responses, virus isolation and viral load by qPCR. EHV-2 was isolated on day 5, and EHV-5 on day 12, earlier than previously reported. γEHV specific a...
Tudor RA, Papich MG, Redding WR.To evaluate pharmacokinetics of once daily i.v. administration of gentamicin sulfate to adult horses that had abdominal surgery. Methods: Prospective study. Methods: 28 adult horses that underwent abdominal surgery for colic. Methods: 14 horses were treated with each dosage of gentamicin (i.e., 6.6 or 4 mg/kg, i.v., q 24 h) and blood samples were collected for pharmacokinetic analysis. Plasma gentamicin concentrations were measured by use of a fluorescence polarization immunoassay. Pharmacokinetic analysis measured the elimination half-life, volume of distribution, and gentamicin total systemi...
Aleman M, Costa LRR, Crowe C, Kass PH.Neuroglycopenia refers to a shortage of glucose in the brain resulting in neuronal dysfunction and death if left untreated. Presumed neuroglycopenia has not been described in horses. Objective: To report neurological signs in horses with presumed neuroglycopenia as the result of severe hypoglycemia. Methods: Ninety horses (hours to 28 years of age) diagnosed with hypoglycemia (blood glucose concentration < 75 mg/dL [< 4.2 mmol/L]). Methods: Retrospective study. Electronic medical records were searched. Signalment, history, complaint, clinical signs, laboratory findings including CSF analysis, ...
Segura D, Monreal L.Template bleeding time (TBT) is considered to be a useful test for detecting platelet function disorders and the effect of platelet-activating drugs, but studies in human medicine have concluded that the test has poor reproducibility and sensitivity. Objective: TBT has poor reproducibility in horses and has insufficient sensitivity to detect the effect of etamsylate on platelet function. Methods: Twenty healthy horses. Methods: TBT was determined and repeated 2 hours and 30 days later. TBT was also performed 2 hours after IV administration of etamsylate. Results: Although no statistical differ...
Kelley DE, Warren LK, Mortensen CJ.L-arginine is an amino acid which can alter pituitary function and increase blood flow to the reproductive tract. The objective was to determine the effect of supplementing 100g of L-arginine on plasma arginine concentrations, follicular dynamics and ovarian and uterine artery blood flow during the estrus that occurs subsequent to foaling. In Experiment 1, mares were fed 100g L-arginine for 1 day during the last 3 weeks of pregnancy and plasma samples taken for every hour for the first 4h and every other hour until 12h.L-arginine supplementation elevated plasma arginine concentrations from 1 t...
Mendoza FJ, Perez-Ecija RA, Monreal L, Estepa JC.Coagulation disorders are frequently diagnosed, especially in hospitalized equidae, and result in increased morbidity and mortality. However, hemostatic reference intervals have not been established for donkeys yet. Objective: To determine whether the most common coagulation parameters used in equine practice are different between healthy donkeys and horses. Methods: Thirty-eight healthy donkeys and 29 healthy horses. Methods: Blood samples were collected to assess both coagulation and fibrinolytic systems by determination of platelet count, fibrinogen concentration, clotting times (prothrombi...
Freeman SL, Bowen IM, Bettschart-Wolfensberger R, Alibhai HI, England GC.The cardiovascular effects of romifidine, an alpha-2 adrenoreceptor agonist, were investigated in six horses using two doses (80 and 120 microg kg(-1)) in a cross-over study design. Cardiac index and mixed venous oxygenation were significantly decreased at 15 and 30 minutes after both doses of romifidine. Systemic vascular resistance was significantly increased with romifidine (120 microg kg(-1)). Arterial blood pressure increased initially and then gradually decreased; the doses of decrease was significant at 90 and 120 minutes with romifidine 80 and 120 microg kg(-1). There were minimal diff...
Witkowska-Piłaszewicz O, Cywińska A, Michlik-Połczyńska K, Czopowicz M, Strzelec K, Biazik A, Parzeniecka-Jaworska M, Crisman M, Witkowski L.Breed specific reference ranges for selected blood parameters are recommended for proper interpretation of blood tests, but there are only few reports dealing with ponies. The purpose of this study was to investigate if blood parameters differ among ponies' classes and to check if general normal values for equine species are applicable to ponies. Results: All, except total protein concentration, biochemical parameter significantly (p < 0.05) differed among ponies' classes. The most pronounced difference was noted in blood lactate concentrations, higher (p < 0.001) in the sma...
Hanis F, Chung ELT, Kamalludin MH, Idrus Z.The high prevalence of abnormal oral behavior (AOB) in working horses has been linked to management issues and the pathophysiology of this behavior remains unclear. Therefore, this study aims to elucidate the blood profile, hormones, and telomere length responses between low and high levels of AOB among different horse working groups. A total of 207 healthy horses from various breeds were initially selected from four working groups (leisure riding, equestrian, endurance, and patrolling) and observed for the time spent on AOB. Then, six horses each with higher and lower AOB than the population ...
