Veterinary medicine for horses encompasses the study and application of medical practices to diagnose, treat, and prevent diseases in equine species. This field involves a comprehensive understanding of equine anatomy, physiology, pathology, and pharmacology. Veterinary practitioners employ a range of diagnostic tools and therapeutic interventions to address health issues in horses, including lameness, gastrointestinal disorders, respiratory conditions, and infectious diseases. Preventative care, such as vaccination and deworming programs, is also a significant aspect of equine veterinary medicine. This page gathers peer-reviewed research studies and scholarly articles that explore various aspects of veterinary medicine as it pertains to horses, including advancements in diagnostic techniques, treatment protocols, and preventive health strategies.
Dubin A, Potempa J, Kurdowska A, Pajdak W, Koj A.Alpha-1-proteinase inhibitors isolated from plasmas of horse, ox, pig, rabbit and man were used for determination of some kinetic parameters of interaction with three horse leucocyte proteinases and bovine pancreatic trypsin and chymotrypsin. Effective molar ratio of enzyme-to-inhibitor, inactivation rate constant and inhibition constant were measured. In horse, ox, pig and rabbit two principal electrophoretic forms of alpha 1-PI could be distinguished. Both forms effectively inhibited trypsin but usually only one form reacted promptly and stoichiometrically with chymotrypsin and leucocyte ela...
Diesing L, Steuber S, Ahmed JS, Hörchner F.The sequential appearance of variable antigen types (VATs) of a clone of Trypanosoma evansi was studied in four ponies. Using luminol-dependent chemiluminescence, VAT populations which had been isolated from parasitemic peaks of single ponies, were tested for specificity with serum samples collected from other ponies. When antibody activity was demonstrated in a combination of trypanosomes and serum, it was concluded that a major VAT appeared in common. In the serum of all animals antibody activity was demonstrated to all VAT populations isolated from the other ponies during the first 4 weeks ...
Cheevers WP, Fatemi-Nainie S, Anderson LW.A retrovirus is spontaneously released into the culture medium of the equine sarcoid-derived MC-1 cell line. The MC-1 virus did not exhibit in vitro transforming activity or replication when tested on equine fibroblasts or a variety of other mammalian cell cultures. Complementary DNA, synthesized using detergent-activated MC-1 virus RNA-dependent DNA polymerase, detected homologous sequences in the DNA of an established equine dermal cell line and in the DNA of primary equine dermal fibroblasts. Iododeoxyuridine or azacytidine induced a replication-deficient endogenous retrovirus in the normal...
Eysker M, Jansen J, Mirck MH.Alternate grazing of horses and sheep as a control measure for gastrointestinal helminthiasis was studied in three grazing experiments in 1981, 1982 and 1983. Each year a group of three mare yearling Shetland ponies, which were kept on a small pasture from spring to autumn, were compared with a similar group which grazed a similar or the same pasture until July and were subsequently removed to a similar pasture which had been grazed by sheep from April to July. In addition both groups were treated with an anthelmintic when the latter group was removed to the sheep pasture. Pasture larval count...
Motie A.An outbreak of suspected equine infectious anaemia (EIA) among a population of 678 horses from 16 farms occurred in the Rupununi Savannahs of Guyana. Clinical signs of EIA were detected in 110 horses. Agar gel immunodiffusion (AGID) tests on 92 sera examined showed positive serological evidence of EIA in 67 (72·8%). The mean packed cell volume of 50 horses studied was 0·178
and the mean red blood cell count was 3·7 × 1012/l with the mean white blood cell count 4·1 × 109/l.
The morbidity rate of the disease was 14·0% and the mortality rate 11·1%. The majority (78%) of all seroposi...
Sławomirski J, Głuszak J.The studies performed on spinal cords of two horses revealed that cells of the nucleus of the own dorsal horn are present in all segments of lumbo-sacral part of the spinal cord. The nucleus is composed of two parts: basal and marginal. Basal part is composed of large and medium size cells situated in 2/3 of the lower part of the grey substance of the dorsal horn. The marginal part of the described nucleus is composed of elongated and spindle shaped cells situated along the dorsal margine of the grey substance of the dorsal horn. Continuity of the nucleus in lumbo-sacral part of the spinal cor...
Firth EC.Low radial neurectomy in the left thoracic limb was performed in 4 mixed-breed weanling horses, with subsequent paralysis of the lateral and common digital extensor muscles. Weight bearing of the denervated and control limbs was discouraged by the use of special shoeing. Clinical signs of flexural deformity were not induced in the horses.
Smith DR, Leach DH, Bell RJ.Anatomical anomalies in the hind feet of a seven month old Appaloosa foal were identified and investigated through the use of gross anatomical dissection, radiography and angiography. Abnormalities were restricted to the distal aspect of both hind legs, the right hind leg being more severely affected. Anatomically the right foot resembled that of an equine fetus of approximately 120 days gestational age. Disruption of vascular perfusion to hoof structures was evident in both hind legs and was related to areas of abnormal bone conformation as well as to areas of abnormal ossification and calcif...
Romanowska D, Szynkiewicz Z, Rita J.Antistreptolysin O (ASO) titers were determined in the sera of 532 horses from stud farms and 436 working horses from small farms. A statistically significant correlation was seen between the ASO titer and the age of the horses. There was a significant difference between mean ASO titer in horses 0-2 years and horses 2-10 years In horses older than 10 years the titer was significantly higher than mean ASO titer for the group. Twenty four of 30 horses in which ASO titer was higher or equal to 80 I.U. had histories which suggested that streptococcal infection had occurred. Clinical and bacteriolo...
Derksen FJ, Stick JA, Scott EA, Robinson NE, Slocombe RF.The effect of left laryngeal hemiplegia on airway flow mechanics in 5 exercising horses was examined, and the efficacy of surgical repair by prosthetic laryngoplasty was evaluated. Measurements of the upper airway flow mechanics were made with horses on a treadmill (incline 6.38 degrees) while standing (period A); walking at 1.3 m/s (period B); trotting at 2.6 m/s (period C); trotting at 4.3 m/s (period D); and standing after exercise (period E). Experiments were done on healthy horses before any surgical manipulation (control), at 10 days after left recurrent laryngeal neurectomy, and at leas...
Short CE, Stauffer JL, Goldberg G, Vainio O.Detomidine is a sedative-analgesic which has a pharmacological profile similar to xylazine. There is evidence that the sedative effects are mediated through alpha-2 adrenoceptors. Cardiopulmonary responses were determined using detomidine as the principal agent and as a preanesthetic prior to the induction of general anesthesia. Compatibility with guaifenesin, sodium thia-mylal and halothane were determined. As in the case of xylazine, detomidine produces a slowing of heart rates. This was found to be either sinus bradycardia or heart block. There may be a corresponding increase in systolic bl...
Bailey E.Segregation distortion was found for a haplotype of the equine lymphocyte antigen (ELA) system in an extended family of American Standardbred horses. In one sire family, consisting of a stallion and his 17 sons and grandsons, the gene for ELA-A10 (A10) was transmitted to 57.7% of 638 offspring scored (P = 0.001). Significant segregation distortion was not seen for mares or for unrelated stallions, regardless of the ELA markers they possessed. Since the effect was seen for this one sire family and not seen for other stallions with A10, it is unlikely that the gene for A10 is the cause of this p...
Tate LP, Newman HC, Cullen JM, Sweeney C.Laryngeal surgery in the equine is customarily and routinely performed by means of a ventral laryngotomy incision. Such procedures are usually performed under deep general anesthesia with the horse in dorsal recumbency. The objective of this work was to determine the efficacy of an endoscopic approach coupled to a Nd:YAG laser fiber in performing arytenoidectomy. Arytenoidectomy is commonly indicated in the treatment of arytenoid chondritis and in the failure of prosthetic implantation for left laryngeal hemiplegia. This preliminary study was undertaken to determine the feasibility of the endo...
Tatarov G, Dilovski M.An avirulent immunogenic virus strain mutant of the causative agent of rhinopneumonia was found to cause abortions and respiratory diseases in horses. The mutant was obtained with the use of a virulent strain that induced strongly manifested clinical symptoms of the disease, and was cultured in cell media containing 5-iodine-2-desoxiuridine as an antimetabolite, following a definite pattern. It was found that the mutant completely lost its virulence, however, it retained its immunogenicity. It likewise retained these newly acquired biologic properties with regard to its being stable and irreve...
Bos H, van der Meij GJ, Dik KJ.Bone structure, nutrient canals, form and definition, and a total evaluation of both fore navicular bones were radiologically evaluated in 169 three- and four-year-old Dutch warmblood mares divided into eleven daughter (half sister) groups. On the basis of the 'total evaluation', differences between the three- and four-year-old horses were detectable. Using the 'total evaluation', significant differences were found between daughter groups consisting of three-year-old mares. These differences support the theory that podotrochleosis may be (partly) due to the presence of genetic factors. The pos...
Dubin A, Potempa J, Turyna B.Horse blood leucocyte cytosol exhibits a broad inhibitory activity against serine proteinases. The purified inhibitor was exposed to investigated enzymes (trypsin, chymotrypsin, elastases and serine proteinase from S. aureus) for variable time and the products were analyzed by gradient polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulphate. The molar ratio I:E, association rate constants k on and inhibition constants Ki for the enzymes and inhibitor were determined. The examined elastases form stable, stoichiometric complexes with the inhibitor (Ki less than 10(-10) M), ...
Skrabalak DS, Henion JD.Betamethasone and its major unconjugated metabolite, 6-beta-hydroxybetamethasone, were detected in equine urine by thin-layer chromatography and characterized by micro-liquid chromatography/mass spectrometry (micro-LC/MS). Their structures were confirmed by a combination of infrared spectroscopy and nuclear magnetic resonance spectroscopy.
Donecker JM, Sams RA, Ashcraft SM.The pharmacokinetics and bioavailability of probenecid given IV and orally at the dosage level of 10 mg/kg of body weight to mares were investigated. Probenecid given IV was characterized by a rapid disposition phase with a mean half-life of 14.0 minutes and a subsequent slower elimination phase with a mean half-life of 87.8 minutes in 5 of 6 mares. In the remaining mare, a rapid disposition phase was not observed, and the half-life of the elimination phase was slower (172 minutes). The mean residence time of probenecid averaged 116 minutes for all 6 mares and 89.2 minutes for the 5 mares with...
Köhler H, Oberlojer HG, Schönbauer M.In the ampulla roof of the wave-like extending horse rectum the muscular coat is only weakly developed as a deltoid-shaped tuna muscularis area, thus forming a place of minor resistance. With regard to the degree of development of the muscular coat a rectal ampulla with a stable form and strong muscles can be distinguished from an ampulla with a labile form and weak muscles. The rupture of the intestinal wall in this region in the case of rupture-experiments as well as the frequent occurrence of diverticula reveals this area as being a place of minor resistance which requires extreme caution d...
Chowdhury SI, Kubin G, Ludwig H.Out of 30 cases of abortion and perinatal deaths in a Lipizzaner stud in Austria 10 mares died after having shown central nervous system disturbances, ataxias and paralysis. The etiological agent of this "abortion storm" was equine herpesvirus type 1 (EHV-1). The restriction enzyme pattern of the DNA from 5 isolates recovered from fetuses has been analyzed and compared with the known reference strains of EHV-1, -2, -4 and an Austrian vaccine strain. The DNA restriction profiles of the Lipizzaner isolates as well as of the vaccine strain could be identified as being typical of abortigenic strai...
De Waal A, Littlejohn A, Potgieter GM, Van der Berg J, Minnaar PI, Smith A.An apparatus was designed to collect four consecutive blood samples from exercising horses. The collection of each sample was controlled by valves activated by radiotelemetry signals transmitted by an observer. Using the device, venous blood samples were collected from ten thoroughbred racehorses before, during and after a 400 m training gallop. Blood glucose increased markedly post-exercise. Both phosphorus and potassium concentrations increased during exercise, decreased post-exercise and recovered to pre-exercise levels within 120 minutes. The system was modified to collect anaerobic sample...
Dória RGS, Reginato GM, Hayasaka YB, Fantinato Neto P, Passarelli D, Arantes JA.Percutaneous decompression of the cecum is a procedure that could be considered for horses with cecal gas distension. The aim of this study was to identify complications such as peritonitis and clinically relevant peritonitis (CRP) after transabdominal cecal trocarization in healthy horses using a cattle trocar and a cecal needle. Mixed breed horses were assigned to three groups (n = 6): horses that underwent trocarization with a cecal needle (G1) or a cattle trocar (G2), and a control group (CG) without cecal trocarization. The same horses were used in each group, respecting a three-month was...
Spurlock GH, Landry SL, Sams R, McGuirk S, Muir WW.Plasma volume, extracellular fluid volume (ECFV), and total body water (TBW) were measured before and after endotoxin (Escherichia coli) administration in 6 conscious adult horses. Evan's blue dye, sodium thiocyanate, and antipyrine were the test substances used to estimate plasma volume, ECFV, and TBW, respectively. Pharmacokinetic analysis of plasma concentration vs time was used to determine changes in body fluid compartments. The pathophysiologic effects of endotoxin were monitored by clinical evaluation, blood chemical changes, and blood gas determinations. All horses became dyspneic with...
Marland A, Sarkar P, Leavitt R.A method for the extraction of diazepam and its metabolites (nordiazepam, temazepam, and oxazepam) from equine urine and serum and their quantitation and confirmation by liquid chromatography-tandem mass spectrometry is presented. Valium, a formulation of diazepam, was administered at a dose of 10 mg intramuscularly to four standard-bred mares. Diazepam is extensively metabolized in the horse to nordiazepam, temazepam, and oxazepam. Diazepam urinary concentrations were found to be less than 6 ng/mL. Nordiazepam was found to be mainly in its glucuronide-conjugated form and was measured out to a...
Driver AJ, Barr FJ, Fuller CJ, Barr AR.Tearing of the medial palmar intercarpal ligament (MPICL) has been recognised as a cause of lameness in the Thoroughbred, but diagnosis is difficult due to the nonspecific clinical signs, and can be achieved only by performing arthroscopy on the mid carpal joint (MCJ). It would be beneficial to be able to image the MPICL using ultrasonography to determine whether pathology is present in the ligament in order to aid diagnosis and prognosis. Objective: To determine whether the MPICL could be imaged using ultrasound from the dorsal aspect of the MCJ, and to describe the technique and normal ultra...
Auer DE, Ng JC, Seawright AA.Free radical oxidation products, namely conjugated dienes, ultraviolet fluorescence (excitation 325 nm, emission 395 nm) and visible fluorescence (excitation 360 nm, emission 460 nm) were measured in equine synovial fluid exposed to free radicals in vitro and in the plasma and synovial fluids of horses with synovial effusions. The synovial effusions were induced by intra-articularly administered carrageenin (0.3 ml, 1%), which rarely resulted in clinical lameness. The free radicals were generated in vitro by mixtures of iron and ethylene diamine tetra acetate (Fe/EDTA) or mixtures of hypoxanth...
Janett F, Aebi L, Burger D, Imboden I, Hässig M, Kindahl H, Thun R.The objective of this study was to evaluate the effect of the non-steroidal anti-inflammatory drug (NSAID) vedaprofen (Quadrisol) on quality and freezability of stallion semen. Experiments were performed using 22 Franches Montagnes stallions from the National Stud in Avenches (Switzerland) randomly divided into a control and test group. Vedaprofen was given orally to all stallions of the test group at the recommended therapeutic dose (initial dose of 2mg/kg followed by 1mg/kg body weight every 12h) for 14 days. Control animals received the same amount of carrier substance. During treatment, bl...
Hernandez D, Yeo WM, Brooks MB, Ness SL, Divers TJ, Stokol T.OBJECTIVE To evaluate the effects of treatment of horses with standard platelet inhibitors on ex vivo inhibition of platelet activation by equine herpesvirus type I (EHV-I). ANIMALS II healthy adult horses. PROCEDURES In a double-blinded, placebo-controlled crossover study, horses were treated orally for 5 days with theophylline (5 mg/kg, q 12 h), pentoxifylline (10 mg/kg, q 12 h), clopidogrel bisulfate (4 mg/kg, q 24 h), acetylsalicylic acid (20 mg/kg, q 24 h), or placebo. Horses received all treatments, each separated by a 3-week washout period. Platelet-rich plasma was prepared from citrate...
Leach DH, Sprigings EJ, Laverty WH.Standard univariate and bivariate statistical methods and two multivariate methods, stepwise regression and factor analyses, were used to analyze 17 stride-timing measurements of 22 racing Thoroughbreds filmed at the beginning of races. All horses were in a right-lead transverse gallop. Data were extracted from frame-by-frame analysis of 16-mm film taken with a high-speed camera. The mean stride duration was 0.405 s and the mean stride frequency was 2.47 strides/s. Stride duration had a higher correlation to the suspension-phase duration (r = 0.864) than to stride-stance-phase duration (r = 0....
Harrington DD.1. The effects of feeding with a purified magnesium-deficient diet (--Mg, 7-8 mg Mg/kg) on horse foal blood serum and tissue concentrations of Mg, calcium and phosphorus were studied, and the results compared with histopathological findings. 2. Serum concentrations of Ca and P were unaffected by feeding with the --Mg diet, whereas serum Mg concentrations decreased from a mean initial (day o) concentration of 0.78 mmol/l to 0.53 mmol/l 7 d after foals were placed on the -Mg diet, and then continued to decrease at a slower rate. 3. Aorta concentrations of Ca and P, but not Mg, were positively co...
van Gurp M, Schamhardt HC, Hartman W, Crowe A.A dynamic model is developed to describe the swing phase of the hindlimb of a normally walking horse. The limb was represented by four rigid segments constrained to move in a sagittal plane only. The mathematical equations of motion of this four-element pendulum were formulated using Lagrange's theorem. The morphometric parameters from the hindlimb segments of 3 horses were determined using high-speed film analysis. Five muscle groups were incorporated in the model. Muscle activity was derived from earlier EMG measurements. Optimization of muscle moments resulted in a simulated swing movement ...
Rutgers LJ, Merkens HW.A method of castration in stallions is reported on, in which primary closure of the wound caused by castration was attempted. Primary wound-healing occurred in 90 per cent of 110 stallions showing normally descended testicles, whereas this proportion was 97.4 per cent in thirty-eight unilaterally cryptorchid stallions in which the normally descended testicle was removed using the method described. It is concluded that the present method of castration will only be successful when surgery is carried out under strictly aseptic conditions.
Barton CK, Hughes KL, Cowan C, Nout-Lomas YS, Nelson BB.A 21-year-old Quarter Horse mare presented with a chronic, progressively worsening left pelvic limb lameness of 3 weeks duration. The initial examination identified a consistent lameness at a walk. Neurological examination showed sensory and gait abnormalities consistent with left femoral nerve dysfunction. The horse minimally advanced the leg cranially and had a shortened stride length at the walk. During the stance phase, the heels of the left hind foot did not contact the ground and the horse quickly took weight off of the limb. Diagnostic imaging (ultrasound and nuclear scintigraphy) exami...
Wijnberg ID, van der Kolk JH, Hiddink EG.Two miniature Shetland ponies showing clinical signs of Digitalis purpurea (foxglove) poisoning were examined. One animal died shortly afterwards, but the second was treated successfully with the anti-arrhythmic agent, phenytoin, and was discharged after 16 days.
Materniak-Kornas M, Rożek W, Rola J, Osiński Z, Löchelt M, Kuźmak J.Equine foamy virus (EFVeca) is a foamy virus of non-primate origin and among the least-studied members of this retroviral subfamily. By sequence comparison, EFVeca shows the highest similarity to bovine foamy virus. In contrast to simian, bovine or feline foamy viruses, knowledge about the epidemiology of EFVeca is still limited. Since preliminary studies suggested EFVeca infections among horses in Poland, we aimed to expand the diagnostics of EFVeca infections by developing specific diagnostic tools and apply them to investigate its prevalence. An ELISA test based on recombinant EFVeca Gag pr...