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.
Smith HJ.A group of seven ponies naturally infected with large numbers of small strongyles and raised under conditions to minimize reinfection were treated periodically over a three year span with thiabendazole at the rate of 44 mg/kg body weight. Based on the absence of worm eggs in the feces following each treatment, thiabendazole removed the adult strongyles present with a new population subsequently developing by maturation of inhibited larvae. It took as many as four or five treatments to eliminate or reduce significantly the worm burdens present in the ponies under the conditions of this study. S...
Hanák J, Chvátal O, Janda J.Sixty seven thoroughbred race horse of various age categories were examined electrocardiographically by bipolar leak-apex of the heart -- withers; length of training corresponded to the age categories. Basic time and voltage criteria of EKG were statistically evaluated according to electrocardiographic curves: TF = 35.1 = %/- 6.82 pulses per min., time P = 0.16 +/- 0.03 sec., PQ = 0.03 +/- 0.04 sec., QRS = 0.12 +/- +/- 0.01 sec., TQc = 0.50 sec., R = 2.83 +/- 0.63 mV, Q = 0.38 +/- 0.31 mV. Repolarization phase of the chamber complex, mainly the T wave, is the most variable component of the who...
Delbeke FT, Debackere M.It is well known that nikethamide (N,N-diethylnicotinamide, CoramineR) is metabolized very rapidly to nicotinamide. Hence, there is difficulty in proving that nikethamide has been used as a doping substance because nicotinamide is a normal physiological metabolite in the organism as well as a vitamin preparation. However, an intermediate metabolite (N-ethylnicotinamide) was found by us in the urine of horses treated with CoramineR. This was characterized by gas chromatography/mass spectrometry, and synthesized and identified as being N-ethylnicotinamide. The excretion and metabolism of niketha...
Tobin T, Swerczek TW, Blake JW.This report concerns the detection and acute toxicity of pine oil (a commercially available disinfectant) after intravenous administration in horses. alpha Terpineol was identified as a major constituent of pine oil. alpha Terpineol was recovered from equine tissues by extraction into heptane and detected by gas chromatography, using either flame ionization detection or pentafluoropropionic anhydride derivatization and electron capture detection. After intravenous injection of 0.1 ml/kg, death due to massive pulmonary edema occurred within minutes. In this animal blood and tissue levels of alp...
Courtot D.At the request of the Service des Haras, our laboratory works on the toxicological problems of the sport-horse. These studies have resulted in the setting up of an anti-doping control for equestrian competitions of various types, not only flat racing. During events, horses, must be calm and docile to the riders' order. Frequently, the latter use tranquillizers to try and win events. The analytical method for the research and identification of these compounds is described. The technique involves successively: 1. alkalinisation of the sample - saliva, blood or urine after enzymatic hydrolysis. 2...
Tobin T, Blake JW.Since procaine has both local anaesthetic and central stimulant actions its presence in the blood or urine of racing horses is forbidden. After rapid intravenous injection of procaine HC1 (2.5 mg/Kg) in thoroughbred mares plasma levels of this drug fell rapidly (t 1/2 alpha = 5 min) and then more slowly (t 1/2 beta = 50.2 min). These kinetics were well fitted by a two compartment open model (Model I). This model gave an apparent Vdbeta for procaine in the horse of about 3,500 litres. Since procaine was about 45% bound to equine plasma protein this gives a true Vdbeta for procaine of about 6,50...
Chvátal O, Hanák J.Surface electric potentials of the heart of four horses were measured by use of unipolar leak with the so called central Wilson's clip; the measurements were performed on 95 precisely fixed places of the equine body. Potentials found out in this way were re-measured with bipolar leaks: the negative electrode was fixed in the place of the highest negative potentials, the positive electrode was gradually attached to places with the highest values of positive potentials. The largest potential differences when the negative electrode was placed in the region of the heart were obtained from the regi...
Roberts BL, Blake JW, Tobin T.Horses pretreated with 6.6 mg/kg of phenylbutazone were injected with 1 mg/kg of furosemide intravenously. Furosemide had no clinically significant effect on either plasma levels or plasma half-life of phenylbutazone. Furosemide reduced urinary levels of phenylbutazone 18-fold to concentrations which may result in inconsistent drug detection in routine screening tests. The results show that it is not possible to monitor compliance with phenylbutazone medication rules by means of urinalysis alone if the use of furosemide is permitted. Furosemide treatment, however, does not interfere with monit...
Jaggard G.The major problems of racing in the United States at the present time are caused by too much racing. This has led to too few horses and small fields. Consequently many owners and trainers are trying to enter their horses too frequently and to race them when they are not really fit to run. The desire to race horses as frequently as possible has led to constant pressure from horsemen through their organizations for so called "permissive medication". Started in the state of Colorado approximately ten years ago this has grown until finally there are only a few states, notably New York and New Jers...
Haywood PE, Chalmers P.The chromatographic and spectroscopic properties of several unusual substances which have been detected in the "alkaloidal" chloroform extract from racehorse urine and saliva samples are reported. Some of these substances have been identified by combined gas chromatography-mass spectrometry and the source of the substance is stated where this is known. Other substances whose identity is not known have been detected and their mass spectra show characteristic amine fragments. The occurrence of these unidentified substances is more frequent in aged urine samples and it would therefore appear that...
Evans JA, Lambert MB, Miller J.The anti-inflammatory drug Ibuprofen [(+/-)-2-(p-isobutylphenyl) propionic acid] was estimated in the blood and urine of a horse using gas-liquid chromatography of the silylated derivative. Levels of the drug in the two body fluids were measured over a period of about 24 hours after administering a 12 gm dose of Ibuprofen. Plasma peak levels were observed within 30 to 60 min, and the drug was no longer detectable in the plasma by 8 hr. Urinary peak levels were observed 200 to 300 min after dosing, and the drug was no longer detectable in the urine by about 28 hr. It was observed that only 2% t...
Muir WW, Milne DW, Skarda RT.Intravenous administration of furosemide in the horse resulted in an immediate and significant decrease in right atrial pressure, pulmonary arterial pressure, pulmonary arterial wedge pressure, cardiac output, and stroke volume (P less than 0.05). There was a significant increase in total systemic vascular resistance and heart rate (P less than 0.05). There were no significant alterations in mean arterial pressure. Coincidental with these hemodynamic changes were increased urine production and associated increase in packed cell volume and total serum protein. All variables except cardiac outpu...
Kundriutskova LA, Kruglikova RI.Hydrolysis of ethers of saturated and unsaturated alcohols and ethers, e.g. phenol and choline, under the action of horse blood serum cholinesterase, was studied. The reactivity towards enzymatic hydrolysis is decreased due to a greater length of the chain in the alcohol residue of the benzoic acid aminoethers; at nCH2 = 4 the compound is a poor substrate. An increase in nydrophobicity of the acyl residue of the ether molecule also leads to a decrease in the Vmax and Km values. In case of cholinesterase substrates, an increase in the molecule hydrophobicity results in an increase of its non-pr...
Brown RF, Houpt KA, Schryver HF.In two adult horses doses of 0.02-0.03 mg/kg diazepam, intravenously, increased 1 hr intake 54-75% above control levels. Intake was stimulated when the diet was a high grain, calorically dense one and also when the diet was a high fiber, calorically dilute one. Two young rapidly growing weanling horses showed an even more pronounced stimulation of intake. Following diazepam 1 hr intake was increased 105-240% above control lelvels. Promazine at a dose of 0.5 mg/kg also stimulated intake in adult horses, but not as markedly as did diazepam. A transquilizer and a neuroleptic appear to have a stim...
Helmstaedter V, Feurle GE, Forssmann WG.Equine pancreas was investigated with immunohistochemical methods to study the distribution of endocrine cells immunoreactive to anti-insulin, anti-glucagon, and anti-somatostatin. A-cells demonstrable by anti-glucagon are located in the center of Langerhans islets and frequently in the duct epithelium. Few A-cells are seen associated to acini. Anti-insulin reactive B-cells form a large zone around the center of the Langerhans islets in which some B-cells lie between exocrine cells and others, although few, are located in the duct epithelium. D-cells stained with anti-somatostatin serum form a...
Rankin JS, Diesem CD.The hindlimbs of 3 ponies and 3 horses were dissected. The hip joint capsule was found to receive articular nerve fibers from the femoral, obturator, cranial gluteal, and sciatic nerves. The nerve fibers were distributed to the fibrous joint capsule and associated capsular ligaments. The stifle joint capsule was found to receive articular branches from the femoral, saphenous, obturator, common peroneal, and tibial nerves. The fibers terminated in the joint capsule, fat pad, patellar and collateral ligaments, and the internally situated meniscal and cruciate ligaments.
Wilbur DJ, Allerhand A.The titration behavior of individual tyrosine residues of myoglobins has been studied by observing the pH dependence of the chemical shifts of Czeta and Cgamma of these residues in natural abundance of 13C Fourier transform NMR spectra (at 15.18 MHz, in 20-mm sample tubes, at 37 degrees) of cyanoferrimyoglobins from sperm whale, horse, and red kangaroo. A comparison of the pH dependence of the spectra of the three proteins yielded specific assignments for the resonance of Tyr-151 (sperm whale) and Tyr-103 (sperm whale and horse). Selective proton decoupling yielded specific assignments for Cze...
Ogbourne CP.A total of 21 species of Cyathostominae was found in the lumen of the large intestine of 86 mature horses of various ages and breeds killed in south-west England during 1972-1974. Cylicostephanus longibursatus, C. goldi, C. calicatus, Cyathostomum catinatum, C. coronatum and Cylicocyclus nassatus were found in over 80% of the horses, while 12 of the remaining species were detected in less than 30%. Quantitative studies on 55 horses showed the adult cyathostome burdens to rise to a sharp peak (average over 400,000/horse) in April-June and a lower one in November-December. Parallel fluctuations ...
Breaud TP, Steelman CD, Roth EE, Adams WV.A tissue culture of Culex pipiens quinquefasciatus Say ovarian cells appeared to support the growth of equine infectious anemia (EIA) virus. Shetland ponies inoculated with 2nd, 7th, 9th, and 11th passages of mediums harvested from infected tissue culture had clinical signs of the disease and became EIA positive on 11, 19, 23, and 43 days after inoculation, respectively.
Charman HP, Bladen S, Gilden RV, Coggins L.Equine infectious anemia virus (EIAV) has a density of 1.154 g/cm3 in sucrose a high-molecular-weight RNA similar in size to Rauscher murine leukemia virus, and an internal virion reverse transcriptase that utilizes the synthetic RNA template poly(rA) but not the synthetic DNA template poly(dA), both with (dT)12 as primer. Although capable of utilizing manganese at low concentrations (approximately 0.1 mM), EIAV reverse transcriptase showed highest activity in the presence of 9 mM magnesium. The major protein of EIAV has a slightly lower molecular weight than the comparable protein of type C v...
DeVico AL, Issel CJ, Le Grice SF, Payne SL, Montelaro RC, Sarngadharan MG.The immunogenicity of the equine infectious anemia virus (EIAV) reverse transcriptase (RT) was examined by immunoblot assay with recombinant EIAV RT. All of the 19 sera from EIAV-infected horses tested contained antibodies that recognized EIAV RT and directly inhibited the polymerase activity of the enzyme. An examination of sera obtained sequentially from two experimentally infected animals revealed that anti-RT antibodies arise early in infection and increase in level. The appearance of the antibodies correlated with progression toward the asymptomatic period of infection.
Martens JG, Stephens KA, Kerchner LJ, Heck FC, Martens RJ.Plasma fibronectin concentrations were measured in clinically healthy mares and their neonatal foals, using a modified human fibronectin competitive enzyme-linked immunosorbent assay. Ranges of plasma fibronectin were established in clinically healthy horses, and the assay was reliable and reproducible. Plasma fibronectin concentrations were similar in mares and foals, both before and after colostrum ingestion.
Oladunni FS, Reedy S, Balasuriya UBR, Horohov DW, Chambers TM.Equine herpesvirus type 4 (EHV-4) is mildly pathogenic but is a common cause of respiratory disease in horses worldwide. We previously demonstrated that unlike EHV-1, EHV-4 is not a potent inducer of type-I IFN and does not suppress that IFN response, especially during late infection, when compared to EHV-1 infection in equine endothelial cells (EECs). Here, we investigated the impact of EHV-4 infection in EECs on type-I IFN signaling molecules at 3, 6, and 12 hpi. Findings from our study revealed that EHV-4 did not induce nor suppress TLR3 and TLR4 expression in EECs at all the studied time...
Seeherman HJ, Morris E, O'Callaghan MW.Discovering the cause of poor performance in racehorses can often represent a considerable challenge eluding the more common diagnostic techniques available at the racetrack. Application of sports medicine techniques to these problem cases can aid in the diagnosis of poor performance. Central to the development of this capability has been the use of highspeed treadmills, allowing the racehorse to be evaluated in the controlled laboratory setting, at exercise intensities equivalent to those of racing. Video and cinematographic gait analysis can be used in the diagnosis of subtle lameness condit...
Archer RM, Lindsay WA, Smith DF, Wilson JW.The vasculature of 22 small colons from dead adult ponies was perfused with latex or barium sulphate solution. The vascular anatomy was studied by use of dissection and alkali digestion of the latex specimens and microangiography of the barium sulphate-perfused specimens. The small colon is supplied by the caudal mesenteric artery. The left colic artery arises from the caudal mesenteric artery, which then becomes the cranial rectal artery. Branches from the left colic and cranial rectal arteries form anastomosing arcades that become narrower distally along the length of the small colon. From t...
Gordon DL, Radtke CL.A 12-year-old Norwegian Fjord gelding was diagnosed with paranasal sinusitis as a post-operative complication of tooth repulsion surgery. The infection with inspissated purulent material persisted despite sinus trephination and lavage, and systemic antimicrobial therapy. Resolution occurred following infusion of a gelatin/penicillin mixture into the right rostral and caudal maxillary sinus. Une sinusite paranasale a été diagnostiquée chez un hongre Fjord âgé de 12 ans comme complication postopératoire d’une chirurgie pour la répulsion d’une dent. L’infection avec du matériel pur...
May SA, Hooke RE, Lees P.The concentration of Percoll required for isolating equine peripheral blood mononuclear cells has been reinvestigated. A poor cell yield was obtained at the 60 per cent concentration already reported. It is recommended that workers specifically interested in high yields of mononuclear cells, for investigation of lymphocyte and monocyte functions, use a concentration of 65 per cent Percoll. However, workers wishing to isolate pure populations of equine neutrophils might consider a concentration of 70 per cent in the upper layer of Percoll used to retain the mononuclear cells.
Kowalski KA, McConnell LA, Sadoff DA, Leid RW.Equine platelets, when treated with the anthelmintic drug diethylcarbamazine (DEC), gave a dose-dependent release of radiolabeled serotonin without concomitant aggregation. At levels of the drug that gave only minimal release of radiolabel, marked dose-dependent inhibition of platelet aggregation to three of four platelet agonists tested--adenosine diphosphate (ADP), collagen, and arachidonic acid--was observed. With ADP, inhibition was observed to be reversed by removal of DEC prior to agonist challenge. However, with collagen, inhibition was only partially reduced by prior removal of DEC; wh...
McCullagh KG, Silver IA.The historical development of "firing" as a treatment for various complaints in animals and man is followed from the first surviving written account by Vegetius (approximately AD 500) to the present day. Changing concepts as to the mechanism of action of the actual cautery are examined in relation to physiological understanding at various times and conflicting views and evident fallacies are discussed. It is of particular interest that firing of "sinewes" (tendons and ligaments) was expressly forbidden until the 18th century. It is concluded that "firing" is an outmoded practice for which ther...
Knych HK, Stanley SD, Arthur RM, McKemie DS.Cetirizine is an antihistamine used in performance horses for the treatment of hypersensitivity reactions and as such a withdrawal time is necessary prior to competition. The objective of the current study was to describe the disposition and elimination of cetirizine following oral administration in order to provide additional serum concentration data upon which appropriate regulatory recommendations can be established. Nine exercised thoroughbred horses were administered 0.4 mg/kg of cetirizine orally BID for a total of five doses. Blood samples were collected immediately prior to drug admin...
The objective of this study was to test the efficacy of an equine pericardial patch for repairing full-thickness defects of the stomach wall. Methods: Circular defects, 1.5 cm in diameter, were created on the anterior wall of the stomach of 12 female New Zealand rabbits. The defects were repaired by an equine pericardial patch. After euthanasia at different time intervals (3 days to 8 weeks) a macroscopic evaluation of the abdominal cavity (including adhesion scoring), mechanical testing and a histological examination of the stomach were performed. Results: The animals survived the surgical pr...
Deane NJ, Davies AS.A photographic study of the angles of 71 carpal joints of horses at the end of a race has shown that overextension of the joint is normal at this stage. Further study is needed to determine the factors which may influence hyperextension, and whether they are relevant to carpal injury.
Pérez W, Martin E.Thirteen fresh equine heads were dissected in an attempt to determine the cause of a groove frequently found on the dorsal border and medial side of the nasal process of the incisive bone. This groove appeared on both sides in 40 out of 44 equine skulls. The sulcus seems to be caused by the combined action of the lateralis nasi muscle and the medial accessory cartilage of the nose (cartilago nasalis accessoria medialis). Other sulci found on the nasal process of the bone may be explained as impressions caused by nerves.