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.
Clem MF, DeBowes RM, Douglass JP, Leipold HW, Chalman JA.The effects of radioulnar fixation were studied in 21 Quarter horse foals by applying a bone plate to the caudal aspect of the proximal part of the ulna, with screws engaging both the radius and the ulna. The plates were applied at 1 month of age in six foals (group I), 5 months of age in six foals (group II), and 7 months of age in three foals (group III). Six foals underwent sham operations at 1 month of age to serve as controls (group IV). Ulnar dysplasia and elbow subluxation developed in all treated foals. The magnitude of ulnar dysplasia was inversely related to the patient's age at fixa...
Watson ED, Stokes CR.The rate of clearance of 125I-labelled polyvinyl pyrrolidone (PVP) from blood was measured in mares as an indicator of macrophage function. In three out of four cycling mares, PVP clearance was slower during oestrus than dioestrus. Similarly, administration of oestrogen to four ovariectomised mares tended to depress PVP clearance compared with clearance from the same mares before they received oestrogen. However, the effect of oestrogen was not statistically significant. Mares susceptible to persistent endometritis had rates of PVP clearance which were similar to those of genitally normal mare...
Archer RM, Parsons JC, Lindsay WA, Wilson JW, Smith DF.Three pairs of longitudinal enterotomies were performed in the small colon of 10 ponies. Each pair consisted of one enterotomy through the antimesenteric band and one through the sacculation. The ponies were destroyed 96 h after surgery. The enterotomies in the two sites were compared for: speed of surgery, adhesions, bursting wall tension, neovascularisation by micro-angiography, and histological reaction. Enterotomies made through the antimesenteric band were superior because they were quicker to perform, stronger, more accurately apposed, and had less inflammation than those made through th...
Todhunter RJ, Parker JE.A recently castrated horse was examined because of preputial and ventral abdominal swelling, prolapse of the preputial fold, and serosanguinous fluid dripping from the external urethral orifice. After a poor response to initial medical management, a urethral laceration was found during exploratory surgery. Half of the ventral portion of the corpus cavernosum penis had been transected. Primary closure was followed by healing without complications.
Pycock JF, Allen WE.The neutrophil is involved in the defence of the mare's uterus against micro-organisms. The ability of Streptococcus zooepidemicus and its growth products to induce shape changes or directional locomotion (chemotaxis) of equine neutrophils was investigated; no effect was found.
Toutain PL, Laurentie M, Autefage A, Alvinerie M.Based on serial blood sampling over 24 h, hydrocortisone was shown to be secreted episodically in the horse. The purpose of the present experiment was to characterize peaks and troughs by analyzing the instantaneous secretion rate profile obtained by a deconvolution technique rather than from the plasma concentration time profile. Kinetic parameters of hydrocortisone were determined following intravenous bolus and intravenous perfusion of hydrocortisone. Stationary and nonlinearity of hydrocortisone disposition were demonstrated. With the use of clearance values calculated from constant perfus...
Dumasia MC, Houghton E.The in vivo biotransformation of (1,2(n)-3H)1-dehydrotestosterone was studied in three equine male castrates and a number of neutral metabolites were identified in the urinary unconjugated and glucuronic acid conjugate fractions by gas chromatography/mass spectrometry. The metabolites were extracted from aliquots of the 0-24 h urine samples by Amberlite XAD-2 and separated into combined unconjugated plus glucuronic acid conjugated and sulphoconjugated fractions by Sephadex LH-20 column chromatography. After enzymatic hydrolysis of the glucuronides, the crude neutral unconjugated steroids plus ...
Freestone JF, Carlson GP, Harrold DR, Church G.Alterations in electrolyte and acid-base balance were studied in 6 horses for 8 hours after furosemide administration (1 mg/kg of body weight, IM), and the results were compared with those for 5 healthy untreated horses (controls) kept under identical environmental conditions. In the treated group, decreases in plasma potassium, chloride, and calcium concentrations and increases in total plasma protein content persisted for the 8-hour observation period, whereas there was no change in plasma sodium concentration, osmolality, or packed cell volume. Plasma bicarbonate concentration and PCO2 rema...
Bauer C.The prevalence of Eimeria leuckarti infection and the intensity of faecal oocyst output were determined in a herd of 14 mares and their foals in northwest Germany using a sedimentation technique at weekly intervals during a summer grazing season from May to September. None of the mares, but all foals shed oocysts on at least one occasion. The patent periods lasted up to 16 weeks. The mean intensity of oocyst output (0.1-33 o.p.g.) was very low. No clinical signs of gastrointestinal disorder were noticed in any of the foals during this study.
Watson ED.Uterine washings were found to promote neutrophil mediated killing of Streptococcus zooepidemicus. Depletion of complement and/or specific antibody from the washings significantly reduced bactericidal activity. Phagocytosis of yeast by uterine washings was complement dependent. Inhibition of the classical pathway significantly reduced opsonic activity indicating that, in addition to direct activation via the alternate pathway, antibody may also be involved in yeast phagocytosis.
Gallagher JR, McMeniman NP.It has been reported that the increasing nutritional demands from mid to late pregnancy of grazing mares may not be met when these stages of gestation coincide with pastures being affected by frost. It was established in this study that grass/legume pastures could support the nutritional requirements of brood mares by providing digestible energy intakes of 68.0 and 91.7 MJ/day and digestible nitrogen intake of 91.2 and 138 g/day during mid and late pregnancy, respectively.
Duncan JL, Arundel JH, Drudge JH, Malczewski A, Slocombe JO.These guidelines have been designed to assist in the planning, operation and interpretation of studies which would serve to assess the efficacy of drugs against internal parasites of horses. Although the term anthelmintic is used in the title and text, these guidelines include studies on drug efficacy against larvae of horse bot flies, Gasterophilus spp, which are non-helminth parasites commonly occurring in the stomach of horses. The advantages, disadvantages and application of critical and controlled tests are presented. Information is also provided on selection of animals, housing, feed, do...
Lea RG, Bolton AE.Two-dimensional crossed immunoelectrophoresis of sera from pregnant and non-pregnant horses, using antisera developed against early pregnant mare serum, revealed the presence of two immunologically related proteins one of which appeared to be specific to the pregnant state. This pregnancy-specific protein had beta 2-electrophoretic mobility and was first detectable at Day 6 after successful mating with a stallion. The second protein had gamma 2-electrophoretic mobility and was present in sera from pregnant and non-pregnant horses. The proteins were termed beta 2-horse pregnancy protein and gam...
Henry MM, Moore JN.Increasing evidence has demonstrated the importance of monocyte procoagulant activity (PCA) in the pathogenesis of coagulopathies in a variety of diseases. Because endotoxin precipitated coagulopathies are common sequelae to intestinal ischemia/endotoxemia in the equine species, we investigated the ability of equine peripheral blood monocytes to express PCA. Monocytes isolated from five healthy adult horses were incubated in vitro with Escherichia coli endotoxin (10 micrograms), and the PCA was measured by the ability of cellular lysates to accelerate the clotting times of equine plasma in a m...
Ellendorff F, Schams D.The neuroendocrine reflex theory of milk ejection was investigated in the horse under natural suckling conditions. To this end 12 lactating mares were provided with acute jugular catheters and with intramammary pressure (IMP) recording catheters. The foal had free access to the contralateral mammary complex. Intramammary pressure could thus be recorded while blood was drawn simultaneously for oxytocin analysis from the undisturbed animal. Suckling periods associated with a characteristic increase in IMP lasted significantly longer than unsuccessful nursing attempts. Elements of successful suck...
Cummings JF, Fubini SL, Todhunter RJ.Digital neurectomies, performed to relieve pain and lameness, are often complicated postoperatively by formation of painful neuromas. In this study attempts were made to deliver lethal doses of neurotoxin to the cell bodies of the transected digital nerve fibres via long-distance retrograde axon transport and, thereby, prevent the regenerative changes that lead to neuroma formation. After applying doxorubicin in various ways to the digital nerve stumps of ponies, degenerating or necrotic neurones appeared only sporadically in the spinal ganglia. Although doxorubicin was largely ineffective in ...
Strain GM, Taylor DS, Graham MC, Kamerling SG.Cortical somatosensory-evoked potentials (SEP) were recorded from thoracic and pelvic limbs in 15 horses (13 Thoroughbreds and 2 Quarter Horses). Ulnar nerve SEP were evoked by electrical stimulation of the lateral palmar branch of the ulnar nerve at the level of the metacarpophalangeal joint. Recordings were taken between electrodes at 2 cm lateral to the vertex (contralateral to the stimulated limb) and the midpoint of the interorbital line. Four peaks were found in all recordings: N1, P1, N2, and P2. Latencies to the peaks were 39.0 +/- 2.7, 45.5 +/- 5.3, 50.4 +/- 5.2, and 62.3 +/- 3.7 ms (...
Calisher CH, Oro JG, Lord RD, Sabattini MS, Karabatsos N.A virus isolated from the blood of a febrile horse in Argentina was identified as a strain of Kairi virus. This is the fifth Bunyamwera serogroup virus isolated from livestock and wild animals in the Americas. Bunyamwera serogroup viruses have been isolated from febrile humans in the Americas and Africa.
Rikihisa Y, Pretzman CI, Johnson GC, Reed SM, Yamamoto S, Andrews F.Ehrlichia risticii has a close antigenic relationship to E. sennetsu. Sera of ponies experimentally infected with E. risticii, the etiologic agent of Potomac horse fever, consistently reacted with E. sennetsu, a human pathogen, in indirect fluorescent-antibody (IFA) testing, while human E. sennetsu convalescent serum reacted with E. risticii by IFA testing and immunoferritin labeling of cells infected in vitro. Two ponies injected intravenously with live E. sennetsu did no develop clinical illness. Subsequent injection with live E. sennetsu did not develop clinical illness. Subsequent injectio...
Smyth GB, Brown RG, Juzwiak JS, Swaim SF, Vaughan JT.A vascularized full-thickness Estlander flap was used to repair a defect involving approximately 40% of the left lower lip of a colt. Postoperative problems were (1) providing nutritional support, (2) minimizing movement at the surgical site, and (3) partial wound dehiscence resulting in a salivary fistula. The surgical site healed well and the colt was left with a fully functional and cosmetic lower lip.
Orsini JA, Elser AH, Galligan DT, Donawick WJ, Kronfeld DS.Selected physical and laboratory findings in 29 horses with acute abdominal crisis were evaluated retrospectively with a logistic regression equation to predict survival or death. Of 17 variables examined, 2 were found to have good predictive correlation. Serum lactate and packed cell volume had a combined predictive value of 94%. Packed cell volume mean values of 43 and 50%, respectively, differentiated survival from death. Serum lactate values of 28.18 mg/dl and 51.28 mg/dl differentiated survival and death. Analysis of data from a previous study of 36 horses with the logistic regression equ...
Fubini SL, Cummings JF, Todhunter RJ.Painful neuroma formation after palmar digital neurectomy in the horse is common. Experimentally, injection of doxorubicin (Adriamycin) into the proximal transected nerve stump has been shown to prevent axon sprouting and neuroma formation for up to 5 months. This procedure was used in 28 horses with navicular disease, preexisting painful neuroma, or wing fractures of the distal phalanx. At 1 month, 16 horses had incisional complications. At 1 year, 15 horses were sound. Eight horses were lame, although three were improved. Three horses required a second surgical procedure, two of which became...
DiPietro JA, Lock TF, Todd KS, Sanecki RK.A controlled test was carried out on 15 pony foals inoculated with 1,500 +/- 108.8 infective Parascaris equorum eggs. The foals were assigned to 3 treatment groups. Treatments given on postinoculation day 11 included 0.2 mg of ivermectin/kg of body weight, formulated as paste (n = 5), or liquid (n = 5), or no treatment (controls; n = 5). The foals were euthanatized on postinoculation day 25, and examined for larvae in the small intestine, lungs, and liver. Larvae were not found in foals treated with ivermectin liquid or paste, whereas significantly (P less than 0.05) higher mean numbers (960.9...
Nequin LG, King SS, Roser JF, Soderstrom BL, Carnevale EM, Neumann KR.The reproductive activity of light horse mares (n=12) was monitored each day from 3 September until 29 January, or until the mares entered anoestrus, by behaviour evaluation, ultrasonography and blood sampling. Follicles, corpora lutea and ovulation, as well as oestradiol, progesterone, and LH and FSH concentrations, were analysed to determine a reproductive profile for the transition into anoestrus. The results of the present study indicate that light horse mares progress through four phases during the autumn transition into anoestrus: (i) normal cycles; (ii) aberrant cycles; (iii) anovulatio...
Sánchez-Pacheco UA, Bahena-Mondragón BM, Hernández-Piedras FR, Soria-Osorio R, Meneses-Acosta A.The immunotherapy agents derived from horses are biological products that allow the neutralization of clinically relevant immunogens, such as the SARS-CoV-2 virus that causes COVID-19, or the neutralization of toxins present in the venoms of snakes, spiders, and other poisonous animals. Due to their importance, detecting adventitious viruses in equine hyperimmune serum (raw material in industrial processes) is a critical step to support the safety of products for human use, and, in consequence, it is a requirement for commercialization and distribution. The safety of the finished product is ba...
Balko JA, Fogle C, Stuska SJ, Fogle JE, Posner LP.Butorphanol-azaperone-medetomidine (BAM™) has not been evaluated in horses. Objective: The objective of this study was to evaluate BAM™ for chemical restraint of feral horses. Methods: Retrospective and prospective descriptive studies. Methods: Data were collected retrospectively from medical records of 28 feral horses immobilised with BAM™ over a 6-year period. Prospectively, 0.0125 mL/kg bwt of BAM™ (butorphanol 27.3 mg/mL, azaperone 9.1 mg/mL and medetomidine 10.9 mg/mL) intramuscularly (im) was administered to eight stallions via dart, and once recumbent, 1.0 mg/kg bwt ketamin...
Honnas CM, Snyder JR, Meagher DM, Ragle CA.Traumatic disruption of the suspensory apparatus is a catastrophic injury in the horse. Although this injury has been described in the adult, little information is available in the foal. This paper describes 3 foals with metacarpophalangeal joint instability caused by traumatic disruption of the suspensory apparatus. Two foals had biaxial proximal sesamoid fractures in a single forelimb, and 1 foal had avulsion of the distal sesamoidean ligaments in 1 forelimb plus biaxial proximal sesamoid fractures in the other forelimb. The foals with single forelimb involvement were managed with splints, a...
Reinemeyer CR, Rohrbach BW.A weighted, random sample of 130 horse owners in Tennessee was selected from subscribers to an equine newsletter published by the Agricultural Extension Service. Data about the participants' farms, horses, parasite control practices, and sources of information regarding equine parasite control were obtained through a telephone survey. The response rate was 98%. The typical respondent kept 4 horses on 2 pastures totaling 15 acres, and did not rotate pastures as a parasite control measure. The majority (83%) of horse owners indicated that they administered anthelmintics according to a regular sc...
Kenney DW, Elsner RW, Franklin DL.Bood flow was measured in the external iliac artery of the
horse during standing and walking. The Franklin Doppler
blood flow-telemetry system was used in this study. The transducer was placed on the external iliac artery using a retroperitoneal approach through the vaginal wall.
Dowling BA, Dart AJ, Hodgson DR.A 2-week-old Miniature Horse foal was referred for evaluation and treatment of a luxated right tarsometatarsal joint. Treatment consisted of closed reduction and internal fixation using two partially threaded Steinmann pins placed in normograde fashion through the tuber calcis into the proximal third metatarsus. Traumatic luxation has been reported to occur in the tarsocrural, proximal intertarsal and tarsometatarsal joints within the equine tarsus. Treatment for luxation of the distal intertarsal joint has not been documented. The treatment method most commonly suggested for tarsal luxation i...
DE SALES JF, JANSEN J.Xenodiagnosis for habronemosis was 96,6% positive in 87 stud horses at Instituto Oswaldo Cuz, Rio de Janeiro, Brazil, from July-November, 1944. The A A. were unable to identify the Habronema larvae obtained from parasitider fly maggots. Measurements and drawings of the larvae are presented.
Klein WR, Rutten VP, Steerenberg PA, Ruitenberg EJ.Horses with sarcoids, cows with ocular squamous cell carcinoma and dogs with mammary tumors were treated with intralesional injection of Bacillus Calmette Guérin. This treatment appeared to be effective in most cases of equine sarcoids, in 50 - 60% of the cows with ocular squamous cell carcinoma and was not effective in dogs with mammary tumors.
van der Linde-Sipman JS, Goedegebuure SA, Kroneman J.In this article a description is given of the clinical and postmortem findings of a persistent right aortic arch in association with a persistent left ductus arteriosus and a ventricular septal defect in a horse.
of surveillance testing, April to June 2017International disease occurrence in the second quarter of 2017These are among matters discussed in the most recent quarterly equine disease surveillance report, prepared by Defra, the Animal Health Trust and the British Equine Veterinary Association.
de Souza Garcia AF, Ribeiro G, de Assis Arantes J, Reginato GM, Xavier NV, Carregaro AB, Silva TJF, Grigoletto R, de Freitas SH, Dória RGS.For horses requiring prolonged daily cephalic intravenous regional limb perfusion (IVRLP), the use of a totally implantable catheter (TIC) could be indicated to reduce complications associated with frequent venipuncture or external catheterization. This study aims to evaluate the implantation technique of the TIC in the cephalic vein of horses for IVRLP, describe the complications associated with the device's placement and use, and assess its viability up to 60 days after implantation. Totally implantable catheters, cut to 15 cm (n = 5) and 46 cm (n = 5) in length, were implanted...
Behn C, Bostedt H.Under field conditions, the diagnosis of foal's diseases relies almost exclusively on the physical examination. As the signs of illness in the equine neonate are frequently vage and non-localizing, the diagnosis of diseases may be problematic. This often causes misinterpretations and leads to ineffective prophylaxis and treatment. The purpose of this study was to evaluate the usefulness of diagnostic ultrasonography of the foal's abdomen under field conditions to provide an optimized technique and to describe the normal findings. Diagnostic ultrasonography of the abdomen was performed after ob...
Tulleners EP.Fifty-seven Standardbred and 44 Thoroughbred racehorses and 1 Thoroughbred polo mare with primary clinical signs of exercise intolerance or respiratory tract noise or combined exercise intolerance and respiratory tract noise were referred for laser correction of epiglottic entrapment. Significantly (P less than 0.001) more Standardbred than Thoroughbred racehorses were affected, compared with the observed hospital population during the same period. At referral, 14 horses did not have evident epiglottic entrapment and were returned to exercise without development of entrapment after treatment, ...
Jaraiz MV, Rodriguez C, San Andres MD, Gonzalez F, San Andres MI.Suxibuzone (SBZ), a nonsteroidal anti-inflammatory drug, was administered to 6 horses at a dose rate of 7.5 mg/kg bwt by intravenous (i.v.) route. Plasma and synovial fluid concentrations of suxibuzone and its main active metabolites, phenylbutazone (PBZ) and oxyphenbutazone (OPBZ), were measured simultaneously by a sensitive and specific high-performance liquid chromatographic method. The pharmacokinetic parameters were determined by noncompartmental analysis. Plasma SBZ concentrations rapidly decreased and were not detectable beyond 20 min after treatment. The parent drug was not detected in...