Equine health encompasses the study and management of diseases, disorders, and overall well-being of horses. It involves understanding various physiological systems, preventive care, and treatment strategies to maintain optimal health in equine populations. Common areas of focus include nutrition, infectious diseases, orthopedic conditions, and reproductive health. Research in equine health aims to advance knowledge on diagnostic methods, therapeutic interventions, and management practices that improve horse welfare and performance. This page collects peer-reviewed research studies and scholarly articles that explore the diverse aspects of equine health, offering insights into current findings and advancements in the field.
Dorn PL, Derse D.Deletion analysis of the equine infectious anemia virus long terminal repeat revealed that sequences responsive to virus-specific transactivation are located within the region spanning the transcriptional start site (-31 to +22). In addition, an active exon of a trans-acting factor (tat) was identified downstream of pol and overlapping env (nucleotides 5264 to 5461). Activation by tat is accompanied by an increase in the steady-state levels of mRNA directed by the equine infectious anemia virus long terminal repeat.
Adams R, Calderwood-Mays MB, Peyton LC.A highly successful surgical technique for removing cutaneous tumors in humans was used in seven horses with cutaneous squamous cell carcinoma (n = 3) or sarcoid (n = 4). In humans, the complete underside of the tumor is evaluated histologically by processing horizontal sections from the tumor base, and orientation between the wound surface and the undersurface of the excised tumor is maintained by mapping both surfaces. The technique ensures that small foci of residual tumor can be located accurately and removed. Based on our experience, three modifications of the human technique are suggeste...
Snijder EJ, Ederveen J, Spaan WJ, Weiss M, Horzinek MC.From 380S particles of Berne virus (proposed family Toroviridae) one species of polyadenylated RNA was isolated. Using agarose gel electrophoresis its length was estimated as 20 kb or greater. When assayed under hypertonic transfection conditions genomic RNA was found to be infectious; RNase treatment destroyed the infectivity. The positive polarity of the molecule was confirmed by filter spot hybridization using cDNA prepared against poly(A)-selected RNA from infected cells. In embryonic mule skin cells infected with Berne virus the presence of five virus-specific, polyadenylated RNA species ...
Katila T, Oijala M.Detomidine was administered throughout 10 pregnancies in eight mares. An intravenous injection of 20 micrograms/kg body weight was given weekly from Day 14 to Day 60 of gestation and thereafter every four weeks until parturition. One mare suffered torsion of the large colon and was destroyed on Day 86; the foetus was normally developed. A further mare aborted at 167 days. The remaining eight pregnancies continued to full term. One foal was delivered by caesarean section because of torticollis and, of the seven foals born spontaneously, one had bilateral upward patellar fixation at one month ol...
Magro AM, Rudofsky UH, Schrader WP, Prendergast J.In vitro IgE-mediated histamine release by equine blood basophils was characterised as the basis for a screening test for immediate hypersensitivity responses in horses. The responses are initiated by inducing agents that are capable of crosslinking or bridging the membrane-bound IgE molecules. The release process is complete within 40 mins. In vitro histamine release is dose-dependent, with a submaximal response at less or greater than the optimal dose of inducing agent. Exogenous calcium is required but not magnesium; the optimal release calcium concentration is 1.0 to 1.5 mM. If an IgE-medi...
Jones RS, Payne-Johnson CE, Seymour CJ.A NUMBER of post general anaesthetic complications are
known to occur in the horse and are well documented (Heath
1981). These include post anaesthetic forelimb lameness o r
ischaemic myopathy (so-called 'radial paralysis') (Trim and
Mason 1974) and spinal cord degeneration (Brearley, Jones,
Kelly and Cox 1986). The only postoperative respiratory
complication which has been documented in the horse is
postoperative hypoxaemia (Gillespie, Hall and 3 1 e r 1969;
Waterman, Jones and Richards 1982).
In a report of the post mortem examinations of 185 injured
human patients who died followi...
McCarthy RN, Jeffcott LB.Six Standardbred horses underwent a 14-week training programme on a treadmill. The training schedule consisted of five weeks of slow work of six to 12 km/day at 5 m/sec. This was followed by a nine week interval programme increasing in its intensity so that for the last three weeks the horses did three to four intervals/day from 600 to 1000 m at or above maximum heart rate. Ultrasound velocity through the third metacarpus showed a significant increase as a result of training. There was also a significant increase in modulus of elasticity, but no change in bone mineral content, bone mineral den...
Kwiatkowski S, Sturma L, Dai MR, Tai HH, Watt DS, Tai CL, Woods WE, Weckman TJ, Yang JM, Wood T.We have developed and evaluated a one step enzyme-linked immunosorbent assay (ELISA) test and a particle concentration fluorescence immunoassay (PCFIA) test for acepromazine as part of a panel of pre- and post-race tests for illegal medications in racing horses. These tests are rapid, sensitive and economical and development of the tests occurred in less than seven months. The ELISA test detects acepromazine with an I-50 of about 150 pg/ml. In vivo, it readily detects the presence of acepromazine or its metabolites in equine blood and urine from 8 to 72 hours or longer, respectively, after adm...
Pilsworth RC, Webbon PM.Five horses, all two year old Thoroughbreds, presented with acute onset hindlimb lameness following moderate to fast exercise. The use of a hand-held scintillation detector after Tc99 MDP injection greatly aided the diagnosis of tibial stress fractures in these horses. Radiological findings were subtle, involving only periosteal new bone and callus at the fracture site. In two cases this took several weeks to develop but in three others was present at the onset of lameness, indicating insidious pre-fracture bone pathology. The site of the most obvious radiological signs was constant in all fiv...
Honnas CM, Wheat JD.Transnasal, axial division of the aryepiglottic fold was performed to correct entrapment of the epiglottis in 20 sedated, standing horses, using a hooked bistoury and topical anesthesia. Presenting complaints included decreased exercise tolerance or loss of racing performance, abnormal respiratory noise, and coughing. The surgical procedure was technically easy to perform with a minimum of instrumentation. The horses were rested an average of 18 days before race training or riding was resumed. Evaluation of racing records or contact with owners indicated that most affected horses competed succ...
Scotti E, Jeffcott LB.An in vitro study on the calcaneus of adult horses (n = 5) and foals (n = 10) was carried out using radiographic photodensitometry, single photon absorptiometry, transmission ultrasound velocity and chemical analysis. Data for trabecular bone content, ash, calcium and phosphorus levels were obtained. As techniques for assessing bone quality, ultrasound velocity was not sufficiently sensitive nor accurate and radiographic photodensitometry was found to be limited value. Photon absorptiometry was both accurate and reproducible, although some variation in bone mineral content and bone mineral den...
Held JP, Patton CS, Shires M.Osteochondroma of the distal portion of the radius was diagnosed in 3 horses with a history of lameness and distention of the common tendon sheath of the superficial and deep digital flexor tendons at the level of the carpal canal. In 2 horses, the exostosis was removed through an incision at the caudal border of the lateral digital extensor muscle above the carpal ligament.
Oijala M, Katila T.Detomidine was administered twice to six foals (14 to 94 days old) using three different doses (10, 20 and 40 micrograms/kg bodyweight intravenously) in a double blind trial. Sedation, analgesia, heart rate and clinically observed side-effects were recorded. Detomidine showed strong sedative effects at all doses tested. Sedation deepened very little by increasing the dose from 10 to 40 micrograms/kg bodyweight, but the duration of the effect was longer. Analgesia was considered good with the largest dose (40 micrograms/kg), and moderate or non-existent with the lower doses. Detomidine caused a...
Gossett KA, McCoy DJ, Jowett PL, Kearney MT.Nitrofurazone solution containing 0.2% nitrofurazone and 99.8% polyethylene glycol was given to 4 healthy horses (2 L in 2 L of lactated Ringer solution, intraperitoneally). Horses developed hypovolemia, hyperosmolality, and mixed respiratory and metabolic acidosis. These changes were largely attributable to polyethylene glycol, but a contribution of nitrofurazone cannot be excluded. Intraperitoneal infusion of nitrofurazone solution in horses is contraindicated.
Morris CM, Field HJ.Tissue specimens obtained from equine herpesvirus-1 (EHV-1), subtype 1-infected aborted foetuses were analysed for the presence of virus DNA by means of Southern blot and dot blot hybridisations. The specificity of the methods was confirmed although the sensitivity was inferior to classical techniques such as virus isolation. However, the possibility of detecting the state of the virus DNA and the ability to distinguish between subtypes were important features, and the dot blot method was shown to have potential for a rapid diagnostic test. This report demonstrates some potential practical app...
Kamerling SG, Cravens WM, Bagwell CA.1. Detomidine is a novel veterinary sedative analgesic which is thought to act by stimulation of alpha 2 adrenoreceptors. The present study was undertaken to determine the direction, time course, and dose-response relationship of detomidine on specific autonomic responses in the unanaesthetized horse. 2. Detomidine was administered intravenously to eight adult thoroughbred racehorses at doses of 0.010-0.040 mg kg-1, according to a double-blind Latin square crossover design. Cardiac and respiratory rates, pupil diameter and rectal temperature were monitored for 180 min postinjection. 3. Detomid...
Leach DH, Dyson S.The instant centres of rotation (ICRs) of each limb joint, other than the coxofemoral joint and those of the digits, were calculated for eight clinically sound horses from tracings of radiographs according to the method of Reuleaux (1963). The majority of ICR positions coincided with the attachment sites of the collateral ligaments. The ICR of the scapulohumeral joint, which does not have collateral ligaments, was caudodistal to the caudal part of the greater tubercle of the humerus. The ICR for the femorotibial joint was located just caudal to the femoral attachment of the collateral ligament...
Sandgren B.Radiographic examination of the tarsocrural, metacarpo- or metatarsophalangeal joints was made in 139 Standardbred horses. Most were under three years old with no history of orthopaedic problems. In the tarsocrural joint, osteochondrosis was observed in 25 (18.1 percent) of the horses (n = 138) and 14 (56 percent) of these were affected bilaterally. In the metatarsophalangeal joint, the most frequent radiographic abnormality was single or multiple bony fragments or defects at the plantar proximal end of the proximal phalanx, which was noticed in 40 (28.8 percent) of the horses (n = 139). The l...
Boero MJ, Kneller SK, Baker GJ, Metcalf MR, Twardock AR.Injury of the lateral collateral ligaments of the tarsocrural joints was diagnosed in nine Standardbred pacers. The average age was 4.9 years. The severity of the lameness varied from severe to subtle and joint effusion was seen in eight of 10 tarsocrural joints. A positive hindlimb flexion test was seen in four of six cases in which results were recorded. The identification of the site of involvement was based on a focal intense 'hot spot' seen on scintigraphy, and new bone formation seen radiographically at the anatomical sites of insertion of the long lateral collateral ligament of the tars...
Roth TL, White KL, Thompson DL, Rahmanian S, Horohov DW.The mechanism by which a horse conceptus-derived immunosuppressive factor (HCS) of M(r) > 100,000 inhibits lymphocyte proliferation was investigated. The factor was obtained from the culture supernatants of 20-day-old horse conceptuses; activity, identified by reduced uptake of [3H]thymidine by mitogen-stimulated lymphocytes, was greatest (P < 0.01) in cultures stimulated by mitogen from pokeweed. HCS also suppressed cell proliferation stimulated by phytohaemagglutinin (P 0.05). Data from a fluorescence-activated cell sorter indicated that supplementation with HCS reduced the number of ...
Thompson AC, Mochal-King C.Hypoparathyroidism is an uncommon endocrine disorder in the horse characterized by a transient or permanent parathyroid hormone insufficiency. Hypoparathyroidism is associated with hypocalcemia and hyperphosphatemia, primarily presenting with clinical signs consistent with hypocalcemia. This case report describes clinical presentation and treatment of a horse with severe hypocalcemia due to primary hypoparathyroidism. A 17-year-old, 542 kg Quarter Horse gelding presented for shaking and tremors. Significant findings include generalized muscle fasciculations, synchronous diaphragmatic flutter, ...
Steenhaut M, Vlaminck K, Gasthuys F.RUPTURE of the stomach is a common complication of
gastric impaction and intestinal reflux or of gastric distention.
After rupture, the general condition of the horse deteriorates
and death follows within a few hours (Tennant, Wheat and
Meagher 1972; McIlwraith 1982).
Dietz and Wiesner (1982) state that partial rupture of the
stomach may result in severe blood loss with circulatory
collapse. In this report a partial rupture of the stomach was
surgically repaired during exploratory laparotomy.
Snow DH, Guy PS.Training and detraining had little effect on the activity of glycogen synthase, hexokinase, glycerol 3-phosphate dehydrogenase or total protein. The activity of 3-hydroxyacyl-CoA dehydrogenase increased markedly during training. After 5 weeks of detraining, the activity of 3-hydroxyacyl-CoA dehydrogenase was returning to pre-training values, whilst by 10-week detraining, the levels were increasing again.
Viljanto M, Kicman AT, Walker CJ, Wolff K, Muir T, Hincks P, Biddle S, Scarth J.Boldenone (1-dehydrotestosterone) is an exogenous anabolic-androgenic steroid (AAS) but is also known to be endogenous in the entire male horse and potentially formed by microbes in voided urine, the gastrointestinal tract, or feed resulting in its detection in urine samples. In this study, equine fecal and urine samples were incubated in the presence of selected stable isotope labeled AAS precursors to investigate whether microbial activity could result in 1-dehydrogenation, in particular the formation of boldenone. Fecal matter was initially selected for investigation because of its high mic...
Schnobrich MR, Gordon DL, Scoggin CF, Bradecamp EA, Canisso IF.Urine pooling, as a persistent condition, is a cause of infertility in mares due to endometrial inflammation and sperm toxicity. Identification of urometra can be challenging in mares presenting with the condition intermittently, or when urine flows into the uterus but is undetectable in the vagina. Currently, there are no reported objective methods to confirm the clinical diagnosis of urine contamination in intrauterine-fluid accumulations. Since creatinine is present in high concentrations in urine and does not diffuse across cell membranes, creatinine concentration should be increased in ma...
Winder NC, Pellegrini A, von Fellenberg R.A peroxidase antiperoxidase technique was used to identify alpha 2-macroglobulin in formalin-fixed sections of normal equine lung and liver and in tissue sections and bronchoalveolar lavage fluid from horses with various lung diseases. Equine peripheral blood leucocytes and bronchoalveolar lavage samples from clinically normal horses were negative for alpha 2-macroglobulin. It was concluded that liver and pulmonary macrophages may be potential sources of alpha 2-macroglobulin. Although alpha 2-macroglobulin may play a role in various chronic bronchointerstitial pneumonias of the horse, it is d...
Heiskanen ML, Huhtinen M, Pirhonen A, Mäenpää PH.Semen from 3 stallions was extended using 2 methods (Kenney extender and a modified Kenney extender), slowly cooled, and stored for 41 +/- 6 (s.d.) h before insemination. An insemination dose (40 ml) contained 1.5-2 billion spermatozoa. In the experiment, 26 mares were inseminated in 30 cycles. The pregnancy rate per cycle obtained with sperm stored in the Kenney extender was 87% (n = 15). When the semen was extended with the modified extender, centrifuged and stored, the pregnancy rate was 60% (n = 15). Inseminations were done every other day until ovulation was detected. If a mare ovulated m...
Wilson DG, Peyton LC, Wolf G.Three horses with equine sarcoids were treated with radical surgical excision and immediate split-thickness skin grafts. Graft take ranged from 50 to 100%, and the epithelial coverage attained resulted in an early functional repair. In no instance was there a recurrence of the sarcoid.
Baxter GM, Allen D, Farrell RL.LARYNGEAL haemiplegia is common in horses and most often
involves the left haemilarynx (Baker 1983; Haynes 1984).
Although specific processes have been incriminated in the
pathogenesis of laryngeal haemiplegia, most cases involve an
idiopathic distal axonopathy of the recurrent laryngeal nerve. The
purpose of this report is to describe a case of laryngeal
haemiplegia associated with an anomalous respiratory cyst. A
description of the lesion, method of surgical repair of the
laryngeal collapse and a proposed term to describe the
abnormality based on pathological and functional consider...
Delbeke FT.Urinary concentrations of the beta-antagonist oxprenolol and some of its major human metabolites were determined following oral administration of a dose of 160 mg to five fasted horses. Quantitation was performed by gas chromatography-mass spectrometry (GC-MS) in the selected ion mode (SIM) by monitoring ion m/z 466 of the heptafluorobutyric derivatives. As early as 2 h after dosage oxprenolol could be detected in hydrolysed urine and remained detectable up to 24 h. Maximum urinary concentrations and excretion rates were obtained between 2 and 12 h. After 12 h only 2.8% of the administered dos...
Lotstra RJ, van den Broek J, Power T, Marr CM, Wijnberg ID.Atrial fibrillation is a common equine arrhythmia. Quinidine alone, or with digoxin are common treatments. Studies on outcome in Warmblood populations in which duration of the AF is often unknown are limited. Objective: To identify the factors that are associated with the success of full treatment cardioversion with oral medication, and establish whether there are differences in these factors between institutions. Methods: Retrospective case series using patient records of Equine University Clinic of Utrecht University and Rossdales Equine Hospital, Newmarket. Methods: Forty-nine horses treate...
Berger J, Valdez S, Puschner B, Leutenegger CM, Gardner IA, Madigan JE.Highly reactive horses may pose risks to humans involved in equestrian activities. Among the factors that may affect horses' reactivity to external stimuli are pesticides used for fly control in equine facilities. The organophosphorus (OP) insecticide tetrachlorvinphos (TCVP) is used as a feed-through larvicide to prevent completion of the fly larval life cycle in horse manure. TCVP exerts its effect by inhibiting the enzyme cholinesterase (ChE) leading to the accumulation of the neurotransmitter acetylcholine (AChE) in synapses of the central and peripheral nervous systems. The aim of the pre...
Methods in enzymologyJanuary 1, 1977
Volume 46 516-523 doi: 10.1016/s0076-6879(77)46062-2
Gopalakrishnan PV, Zimmerman UJ, Karush F.Affinity labeling studies with anticarbohydrate antibodies have been very limited. In earlier studies, diazoniumphenyl glycosides were employed as affinity labeling reagents for rabbit and equine anti-p-azophenyl-β-lactoside and p-azophenyl- β-galactoside antibodies. Although these antibodies were heterogeneous, it was possible to identify the labeled residues in the heavy or light chains since the modified residues had characteristic absorption spectra. With the discovery of bacterial cell walls of Streptococcus groups A and C induced antipolysaccharide antibodies of restricted heterogeneit...
The Journal of heredityMarch 6, 1998
Volume 89, Issue 1 104-106 doi: 10.1093/jhered/89.1.104
Duffield DA, Goldie PL.In a study of 2,786 tobiano and non-tobiano horses involved in paint horse breeding programs throughout the United States, the inheritance of the tobiano color pattern gene was tracked in pedigrees using the tightly linked polymorphic albumin gene. The dominant tobiano allele (T(o)), which produces the tobiano spotting pattern in horses, was in coupling with both AIA and AIB alleles at the albumin locus. The frequency of the T(o):AIA linkage phase among all the homozygous tobiano horses in this study including offspring and parents (N = 127), was 0.08. The T(o):AIB linkage phase was the most f...
Lehner AF, Hughes CG, Harkins JD, Nickerson C, Mollett B, Dirikolu L, Bosken J, Camargo F, Boyles J, Troppmann A, Karpiesiuk WW, Woods WE, Tobin T.We have investigated the detection, confirmation, and metabolism of the beta-adrenergic agonist ractopamine administered as Paylean to the horse. A Testing Components Corporation enzyme-linked imunosorbent assay (ELISA) kit for ractopamine displayed linear response between 1.0 and 100 ng/mL with an I-50 of 10 ng/mL and an effective screening limit of detection of 50 ng/mL. The kit was readily able to detect ractopamine equivalents in unhydrolyzed urine up to 24 h following a 300-mg oral dose. Gas chromatography-mass spectrometry (GC-MS) confirmation comprised glucuronidase treatment, solid-pha...
Giraudet A, Hinchcliff KW, Kohn CW, McKeever KH.Plasma insulin concentration of many species has a characteristic early or acute-phase response in the minutes after IV administration of glucose. However, the plasma insulin response of horses soon after the IV administration of glucose has not been examined, whereas the more prolonged response has been evaluated. We examined the plasma insulin and glucose concentration responses of adult mares during the 30 minutes after rapid IV administration of glucose (0.33 g/kg of body weight). Plasma glucose concentration peaked at 664 +/- 54 mg/dl within 1 minute of cessation of glucose administration...