Veterinary research in horses encompasses the study of diseases, health management, and medical treatments specific to equine species. This field investigates various aspects of horse health, including infectious diseases, metabolic disorders, and musculoskeletal conditions. Researchers focus on understanding the pathophysiology of equine ailments, developing diagnostic tools, and evaluating therapeutic interventions. The study of horse health also involves examining preventive measures such as vaccination protocols and nutritional management to promote overall well-being. This page collects peer-reviewed research studies and scholarly articles that explore the diverse areas of veterinary science related to horses, providing insights into disease mechanisms, treatment strategies, and advancements in equine healthcare.
Cybinski DH, Zakrzewski H.CSIRO 368 virus was isolated from blood collected in the Northern Territory from a healthy cow and electron microscope studies showed that the isolate had rhabdovirus morphology. Fluorescent antibody studies and complement fixation tests related the virus to bovine ephemeral fever (BEF) virus. Neutralization tests in both suckling mice and Vero cells showed that the virus was not BEF virus. Antibodies to CSIRO 368 virus were found in cattle sera from northern and eastern Australia and Papua New Guinea. Antibodies were found in 16 out of 45 buffalo, some of which also had antibodies to BEF viru...
Littlejohn A, Button C, Bowles F.Mean modal vectors of P1, P2 and QRS were determined in the 3 planes of a semi-orthogonal EKG lead system in 17 horses and ponies with chronic obstructive pulmonary disease (COPD) and in 17 clinically normal horses and ponies. Subjects were paired so that the heart rates of each pair were not dissimilar by more than 2 cycles per minute. Probably significant differences were observed between the mean angles of P1 vectors in the transverse and sagittal planes (T plane, normal = 324 degrees +/- 24,6 degrees, COPD = 342 degrees +/- 21,0 degrees, t = 2,0, P less than 0,05; S plane, normal = 331 deg...
Nelson R, Hampe DW.Tracheal mucous transport rates were measured in 12 nonanesthetized horses after an intratracheal injection of 99mtechnetium-sulfur colloid. The transport rate of the subsequent bolus of radioactivity was determined, using a portable scaler rate meter fitted with a high-energy gamma-scintillation probe. A gamma-scintillation camera was used to verify bolus form and movement in 1 horse. The mean tracheal mucous transport rate was 1.66 +/- 0.24 cm/min.
Bastianello SS.A survey was carried out on the neoplasms of horses, donkeys and mules which are recorded in the registration files of the Section of Pathology of the Veterinary Research Institute, Onderstepoort, in the Republic of South Africa, over a 40-year period from 1935 to 1974. A total of 378 tumours are recorded, 339 of which were in horses, 32 in mules and 7 in donkeys. Sarcoids (38%), squamous cell carcinomas (23,5%), fibromas (8,2%), melanomas (8,0%), papillomas (4,5%), fibrosarcomas (3,4%) and lymphosarcomas (3,0%) accounted for 88,6% of the total. Of the 58 sarcoids for which the site or origin ...
Suquet CM, Leid RW.Platelet-activating factor (PAF), a lipid released as a result of immediate allergic reactions from basophils and mast cells as well as by a variety of other cell types and stimuli, is one of the most potent platelet agonists and hypotensive agents known. Equine platelets stimulated over a wide range of PAF concentrations aggregated in a time- and dose-dependent manner. Maximum aggregation was observed at concentrations of PAF as low as 3.58 x 10(-14) M with platelet-rich plasma (PRP) and 3.58 x 10(-16) M with washed platelets. Furthermore, the aggregation observed did not appear to be breed-d...
Braverman Y, Ungar-Waron H, Frith K, Adler H, Danieli Y, Baker KP, Quinn PJ.A survey of sweet itch in horses in Israel based on a questionnaire to owners reported that 158 of 723 horses (21.8 per cent) had sweet itch lesions. The results indicated that the likelihood of a horse acquiring sweet itch decreased with increasing altitude but no definite association with rainfall zones was evident. Variation in the density of the horse population, however, obscured these observations. In the population surveyed, stallions were more sensitive than mares and pale horses appeared to be less sensitive than dark ones, but the sample size of this latter group was much smaller. In...
DiPietro JA, Paul A, Todd KS.Forty horses from a herd known to have benzimidazole-resistant small strongyles were treated with mebendazole (8.8 mg/kg) or combinations of mebendazole and piperazine monohydrochloride (25, 40, or 55 mg of piperazine base/kg). Pretreatment and 7-day posttreatment fecal examinations were done. Fecal cultures and strongyle egg per gram (epg) counts, and in vitro testing for benzimidazole resistance were performed. Results of fecal examinations prior to treatment were similar in all horses, and results of testing were positive for benzimidazole resistance. Horses treated with mebendazole and pip...
de Vries PJ, van der Holst W.The reliability of determination of the plasma progesterone level within approximately eighteen days after ovulation in the pregnancy diagnosis of mares is examined in the present study. Studies were done in seventy-five mares, a number of which were served or inseminated during several cycles so that a total number of eighty-seven blood samples were obtained. On the analogy of other authors, the progesterone level above which mares were believed to be pregnant and below which they were assumed to be non-pregnant, was set at 2 ng/ml. The twenty-five mares in which the level was below 2 ng/ml. ...
Zamansky GB, Arundel C, Nagasawa H, Little JB.The growth of two human diploid skin fibroblast cell lines, originally grown in medium supplemented with foetal bovine serum and later adapted to medium supplemented with newborn bovine, bovine calf or horse serum, has been studied. Prolonged generation times increased cell volumes and decreased plating efficiencies were observed in cultures grown in newborn bovine, bovine calf or horse serum. In general, the deleterious effects were most severe as a result of growth in bovine calf or horse serum. In the light of the present findings, we believe investigators should exert great caution in swit...
Oprescu SV.The paper presents the results of some genetic studies accomplished in Romania in the field of pathology of reproduction in domestic animals (pseudohermaphroditism in horses, testicular hypoplasia in he-goats, intersexuality in pigs, freemartinism and genital infantilism in cattle). Also, the use of the cytogenetic test in genetic prophylaxis in pigs and cattle was shown. In addition, the methods for detecting genitors with undesirable genes were devised and perspectives for the development of hereditary hygiene discussed.
Mishra PC, Leach DH.The extrinsic and intrinsic venous drainage of the equine hoof have previously been poorly described. There is also an absence of information about the venous organisation of both primary and secondary dermal lamellae of the hoof wall. The purpose of this study was to describe the normal venous pattern of the horse hoof, especially that associated with the dermal lamellae of the wall. The venous organisation of 46 pairs of hooves from clinically healthy horses was studied using standard plastic vascular corrosion casts and histological sections. A consistent pattern of venous organisation was ...
Bruyninckx WJ, Blancquaert AM.Horse mononuclear cells were separated from whole blood using neutral density gradient centrifugation on Isopaque-Ficoll. The resulting cell suspension was comparable in composition with similarly prepared human and bovine mononuclear cell preparations. The relative concentration of monocytes was increased by the use of a gradient with density lower than that originally proposed by Böyum (Böyum, A. 1968. Scand. J. Clin. Lab. Investig. 21 supple. 97:77-89). Contamination by neutrophils was limited either by using a gradient medium of lower density or by replacing Isopaque-Ficoll by Percoll-0....
Combie JD, Nugent TE, Tobin T.Morphine could be detected in horses dosed with 0.1 mg of drug/kg of body weight for up to 48 hours in blood and 144 hours in urine. This dose of morphine elicited no observable effects and is a suggested analgesic dose. Computer analysis revealed that a 3-compartment open system was the best fitting model with a serum half life (t1/2(beta)) of 87.9 minutes and a urine t1/2(beta) of 101.1 minutes. Binding to equine serum proteins was linear over a drug concentration range of 3.88 X 10(-5)M to 3.50 X 10(-8)M and averaged 31.6%. In RBC-partitioning experiments, 78.1% of the drug was found in the...
Firth EC, Hartman W.The change in the degree of fitting of the opposing articular cartilage surfaces of the radiocarpal joint of foals was studied in vitro using a pneumatic loading device. The thickness of the articular cartilage of the distal radius was examined using radiographic and histological techniques. The thickest cartilage corresponded with the approximate centre of the contact area of the opposing articular surface. The variations in articular cartilage contact area and thickness are discussed.
Pan LG, Forster HV, Bisgard GE, Kaminski RP, Dorsey SM, Busch MA.We studied blood gases in ponies to assess the relationship of alveolar ventilation (VA) to pulmonary CO2 delivery during moderate treadmill exercise. In normal ponies for 1.8, 3, or 6 mph, respectively, partial pressure of CO2 in arterial blood (PaCO2) decreased maximally by 3.1, 4.4, and 5.7 Torr at 30-90 s of exercise and remained below rest by 1.4, 2.3, and 4.5 Torr during steady-state (4-8 min) exercise (P less than 0.01). Partial pressure of O2 in arterial blood (PaO2) and arterial pH, (pHa) also reflected hyperventilation. Mixed venus CO2 partial pressure (PVCO2) decreased 2.3 and 2.9 T...
Klei TR, Chapman MR, Torbert BJ, McClure JR.An indirect fluorescent antibody assay (IFA) was developed using Strongylus vulgaris third stage larvae (L3) as antigens. Observations using the IFA indicate that a species-specific antibody response to S. vulgaris L3 develops in S. vulgaris-infected ponies and that some surface L3 antigens are shared by adult worms. Sequential antibody levels against S. vulgaris were measured in strongyle-naive and in immune ponies following initial and challenge infections using the IFA and an indirect hemagglutination assay (IHA). Antibody levels measured by IFA increased faster following initial infections...
Rehbein G, Heidrich-Joswig S.Eight ponies infected with Babesia equi were investigated for their serological response to B. equi schizont and piroplasm antigen with the indirect fluorescent antibody test (IFAT) and complement fixation test (CFT). Piroplasm antigen was prepared from an infected splenectomized pony, while schizont antigen was produced from cultured lymphoid cells which contained B. equi macroschizonts. The IFAT detected a rise in antibody titres to schizont antigen as well as to piroplasm antigen, but differences were obtained in the duration of antibody detection. Significant antibody titres to piroplasm a...
Brown MP, Pool RR.Braided carbon fiber sutures were used to repair surgically transected or lacerated digital flexor tendons of 20 mature horses (10 experimental and 10 clinical cases). In addition, 4 experimental horses had tenectomies that were not surgically repaired; these served as controls for the horses with carbon-implanted tendons. Six of the 10 clinically affected horses were returned to their intended use; 2 were euthanatized because of complications and 2 were still recuperating. The experimental horses were euthanatized at 12 days and 1, 2, 4, 8, and 12 months. Tendon scars were structurally and fu...
Acland HM, Kenney RM.Twenty-three mares were infected with contagious equine metritis organism by intrauterine inoculation, and necropsied after intervals of two to 116 days. Severe diffuse subacute salpingitis was seen in one mare, and mild multifocal subacute salpingitis was common. Severe diffuse endometritis and cervicitis initially were acute and became more severe, subacute and predominantly plasmacytic by 14 days, then declined but persisted as mild diffuse or multifocal inflammation for the rest of the experimental period. Vaginitis arose in parallel but resolved after 70 days. There were no lesions in the...
Davies JV, Gerring EL.The effect of acepromazine, Buscopan (Crown Chemicals), pethidine and methadone was evaluated in ponies prepared with Thiry-Vella (T-V) loops. Motility was assessed by electrophysiological means (bipolar electrodes and strain gauge transducers) and by the passage through the T-V loop of a fluid test meal. Results were obtained from 26 experiments in three ponies and compared with six control experiments, in which saline had been administered to the same ponies. Each pony acted as its own control in each experiment and pre and post treatment values for slow wave frequency, spiking activity, del...
Davies JV, Gerring EL.Motility patterns in the equine small intestine were investigated in eight ponies. Muscular activity was assessed by means of extramural strain gauge transducers, bi-polar electrodes and in three of the animals, fitted with Thiry-Vella loops, the transit of fluid. Circular muscle contractions were preceded by spiking superimposed on the slow wave and fluid transit in the loops correlated with both these events.
Parker WG, Sullivan JJ, Larson LL.The diagnostic value of rectal palpation and immunological assay of PMSG was tested at different stages of pregnancy in mares inseminated with frozen semen in three separate studies. The results were based on foaling success and particular attention was paid to the numbers of inconsistent results obtained by the two tests. Generally, the number of false positive diagnoses was lower for the immunological assay than for palpation in early pregnancy (Days 40 to 60) and the relationship became reversed later in gestation.
Pazdera J, Hruban V, Pichrtová J, Müller Z, Jílek F.Using a multilocus DNA probe, individual - specific hybridization patterns, the so-called DNA fingerprints (TAB) were determined in six horse families by the DNA fingerprinting method. The probe with evolutionally preserved nucleotide sequence from bacteriophage M13 determines hypervariable regions placed in genomic minisatellite DNA. The use of this probe permits an identification of an individual and execution of paternity relationships with a probability over 99.99 per cent.
Akbari Shahkhosravi N, Kakavand R, Davies HMS, Komeili A.The health and performance of horses are significantly affected by diseases associated with the hoof. Laminitis is a critical hoof disease that causes pain and, potentially, severe hoof and bone pathology. Objective: To generate an equine hoof finite element (FE) model to investigate the impact of normal and toe-in hoof conformations on the degeneration (decrease in elastic modulus) of the laminar junction (LJ), as occurs in chronic laminitis. Methods: Computer software modelling. Methods: A hoof FE model was generated to investigate the biomechanics of hoof laminitis. A 3D model, consisting o...
Gordon BJ, Latimer KS, Murray CM, Moore JN.Continuous-flow centrifugation leukapheresis techniques were used to collect 300-ml volumes of leukocyte-rich plasma from 5 nonmedicated horses and from 5 corticosteroid-stimulated horses. White blood cell counts and differential counts were performed on the horses before (base line) and up to 48 hours after leukapheresis. Systemic administration of hydrocortisone increased numbers of total WBC and neutrophils and improved harvest of these cells. Nonmedicated horses had a mean yield of 3.38 X 10(10) leukocytes in the 300-ml volume. Stimulated horses yielded a mean of 6.88 X 10(10) leukocytes. ...
Echeverria KO, Lascola KM, Giguère S, Foreman JH.Minocycline is commonly used to treat bacterial and rickettsial infections in adult horses but limited information exists regarding the impact of feeding on its oral bioavailability. This study's objective was to compare the pharmacokinetics of minocycline after administration of a single oral dose in horses with feed withheld and with feed provided at the time of drug administration. Six healthy adult horses were administered intravenous (2.2 mg/kg) and oral minocycline (4 mg/kg) with access to hay at the time of oral drug administration (fed) and with access to hay delayed for 2 hr after ...
Gilhooly MH, Eades SC, Stokes AM, Moore RM.To measure and compare palmar digital venous plasma nitric oxide (NO) concentrations and digital arterial blood flow after application of topical nitroglycerine (NTG). Methods: Experimental study. Methods: Healthy adult horses (n=8). Methods: Digital blood flow was measured by an ultrasonic Doppler flow probe surgically implanted around the medial palmar digital artery. Blood was collected from a catheter placed in the medial palmar digital vein for quantification of NO. NTG patches, NTG ointment or control patches were placed over the palmar digital vessels at the level of the fetlock. Two ho...
Pycock J.Jonathan Pycock is one of three equine claims consultants with the Veterinary Defence Society. His career in equine reproduction, and lecturing on the same topic, has given him the opportunity to work and travel widely, and ensure his work/life balance stays in sync.
Gehlen H, Groner U, Rohn K, Stadler P.In the present study, a right heart catheterisation was carried out on three consecutive days in 17 healthy horses to evaluate the day-to-day variability of cardiac pressure values. Cardiac pressure values were measured in the right atrium, the right ventricle, the pulmonary artery, and the pulmonary capillaries (pulmonary artery wedge pressure). Additionally it was examined wether the cardiac pressure variability was influenced by the heart rate and if there are differences between trained and untrained horses. Beside the coefficient of variances, statistical analysis with assessment of varia...
Wijnberg ID, van der Kolk JH, van Garderen E, Binkhorst GJ.A 18-year-old Dutch Warmblood mare was referred for colic. Upon arrival, lethargy, blindness, head pressing, ataxia, and circling were the main clinical signs. On rectal examination a hard mass and oedema around the cranial mesenteric artery were palpated. Plasma liver enzyme activities and the ammonia level were elevated. Atrial fibrillation with a pulse frequency of 36-52 beats per minute was noticed. On both sides a holosystolic murmer with the maximum intensity on the right side could be auscultated. Postmortem examination revealed eccentric hypertrophy of the right atrium and a pale spott...
Brown-Douglas CG, Firth EC, Parkinson TJ, Fennessy PF.To determine the responsiveness of the pituitary-gonadal axis of peri-pubertal colts to GnRH, buserelin (0.5, 1, 5, 10 and 40 microg) was given to 13 male Thoroughbred yearlings ( n=3-8 colts per dose). Jugular venous blood samples were taken at -10, 0, 10, 20, 30, 40, 60, 120 and 180 min relative to buserelin administration. Increases (P < 0.05) in LH concentrations occurred in colts that received 5, 10, or 40 microg buserelin, but not in those that received 0.5 or 1 microg. Peak LH concentrations and mean area under the curve were higher (P < 0.05) in colts receiving 40 microg busereli...
Hess EK, Reinhart JM, Anderson MJ, Jannasch AS, Taylor SD.Thiamine is a vital co-factor for several anti-inflammatory and antioxidant processes that are critical for mitigation of sepsis-associated inflammation, but pharmacokinetic (PK) analysis has not been reported in horses. We hypothesized that IV thiamine hydrochloride (TH) at increasing dosages would result in corresponding increases in plasma thiamine concentrations without causing adverse effects. A randomized cross-over study was performed in 9 healthy horses that each received TH at 5, 10, and 20 mg/kg IV. Blood was collected immediately prior to drug administration and at several time poi...
Polikepahad S, Haque M, Francis J, Moore RM, Venugopal CS.The purpose of the study was to determine and compare the expression of endothelin (ET) receptors in the peripheral lungs of healthy horses and those affected with recurrent airway obstruction (RAO) using reverse transcriptase polymerase chain reaction (RT-PCR), real-time PCR, Western blot analysis, and immunohistochemical techniques. Two groups of horses (7 healthy and 7 RAO-affected) were selected from a pool of horses destined for euthanasia. The grouping of horses was based on the history, clinical scoring, and pulmonary function testing. After euthanasia, gross postmortem evaluation of th...
Otani S, Arimitsu Y, Akama K.Antileptospiral sera from hyperimmunized horses were fractionated by gel filtration on Sephadex G-200 or by starch block electrophoresis. The fractions were examined quantitatively for leptospiricidal, agglutinating and complement fixing activities. The leptospiricidal activity was higher in the 78 globulin fraction than in the 19S globulin fraction, while the agglutinating activity was shared by both the fractions being higher in the 19S fraction. Complement fixing activity was found evenly in both the fractions. Leptospiricidal and complement fixing activities were higher in gamma-globulin t...
Wullschleger L, Weisse B, Blaser D, Fürst AE.Four radii of different horses were tested in three-point bending and in pure torsion. Detailed finite element (FE) models of these long bones were established by means of computed-tomography (CT) images and tests simulated for both load cases. For the allocation of the local isotropic material stiffness, individual exponential functions were applied whose factor and exponent were determined solely by fitting them to the measured torsional stiffness and bending stiffness of the entire bones. These stiffness functions referring directly to the CT number and having exponents between 1.5 and 2 we...
Milne EM, Pogson DM, Else RW, Rowland AC.One case of caecocaecal intussusception (case 1) and one case of caecocolic intussusception (case 2) in ponies are described. Case 1 showed mild abdominal discomfort for seven days followed by sudden death whereas case 2 showed continuous moderate pain for three weeks. At post mortem examination, case 1 showed intussusception of the base of the caecum into the body whereas in case 2, the entire caecum had invaginated into the right ventral colon. Histopathological examination showed that the lesions in both animals had been present for a long time.
Chacon-Arellano JT, Woolley DM.Smooth muscle cells are present in the tunica albuginea testis of the horse, pig and sheep. typical fusiform muscle cells constitute a distinct layer up to 0.3 micrometer thick in the horse; there are fewer muscle cells, mainly of the branched form, in the pig; whereas in the sheep the muscle component is least well developed, with some cells intermediate in form between smooth muscle cells and fibroblasts (myofibroblasts). Attention is drawn to the continuity of this capsular muscle with the smooth muscle associated with the vasculature of the spermatic cord in the horse. This association sug...
Hunt JP, Haywood PE, Moss MS.A gas chromatographic screening procedure for the non-steroidal anti-inflammatory group of drugs is described. The method invovles on-column methylation of the carboxylic acid group using trimethylanilinium hydroxide as the methylating reagent. Fifteen such drugs were studied. Eight of these were detected in urine collected from horses that had received these compounds orally and for these drugs, rates of urinary excretion are recorded. Seven other members of this group of drugs were shown to be detectable by this procedure but in these cases the drug was added to urine and not administered to...