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.
Toutain PL, Oukessou M, Autefage A, Alvinerie M.Using a specific high-performance liquid chromatographic technique, plasma hydrocortisone values were measured hourly in 6 horses and every 10 minutes in 4 horses over 24 hours. Both circadian and episodic variation was observed. The mean plasma hydrocortisone concentration was a maximum of 58.8 +/- 9.54 ng/ml at 9.19 +/- 0.59 hr and a minimum of 27.85 +/- 6.85 g/ml at 21.19 +/- 0.59 hr. The number of episodes of secretion was 10.0 +/- 1.41; the mean amplitude and duration of peak were 26.21 +/- 3.71 ng/ml and 105.25 +/- 21.24 min respectively.
Pause B, Nolte I, Geiss V, Mayer H, Lasch HG.A thoroughbred horse, suffering from intermittent lameness was treated with streptokinase, urokinase and warfarin. The appearing fibrinolytic changes in coagulation were exhibited in a resonance thrombogram. In attendant coagulation studies fibrinogen- and fibrin-degradation products were demonstrated. The stallion does not show any lameness since the end of the treatment and is standing in a breeding station since March 1988.
Ralston SL.A survey was taken of dietary management and training schedules of 54 horses competing in two 160 km endurance races. A total of 52 owners, representing 54 horses, responded to a questionnaire distributed prior to the races. Diet and training schedules were compared between horses that successfully completed the races and those that were eliminated for metabolic reasons. Horses that completed the races were 11.5 +/- 4 years old, weighed 429 +/- 4.5 kg and were ridden 61 +/- 32 km a week when training. Feed intake was reported as "free choice hay or pasture" by 34 of the respondents. Dry matter...
Cochaux P, Van Sande J, Swillens S, Dumont JE.The characteristics of the iodide-induced inhibition of cyclic AMP accumulation in dog thyroid slices have been previously described [Van Sande, J., Cochaux, P. and Dumont, J. E. (1985) Mol. Cell. Endocrinol. 40, 181-192]. In the present study we investigated the characteristics of the iodide-induced inhibition of adenylate cyclase activity in dog and horse thyroid. The inhibition of cyclic AMP accumulation by iodide in stimulated horse thyroid slices was similar to that observed in dog thyroid slices. The inhibition was observed in slices stimulated by thyroid-stimulating hormone, cholera tox...
Jaussaud P, Courtot D, Guyot JL, Paris J.The main metabolite of flunixin, a hydroxylated product, has been identified by gas chromatography-mass spectrometry and 1H NMR spectroscopy in equine urine and plasma. The method also permits the qualitative monitoring of the urinary elimination of the drug and its metabolite. The two products are detected up to 175 and 54 h, respectively, after a single intravenous administration at the dose of 1 mg/kg. Simultaneous detection of the two compounds increases the reliability of anti-doping control analysis.
Chottard G, Michelon M, Hervé M, Hervé G.Complex formation between horse heart ferricytochrome c and large three-dimensional polyanions has been investigated, in order to study the influence of surface electrostatic interactions on the structural and redox properties of cytochrome c. Cytochrome c binds the large heteropolytungstates (NaSb9W21O86)18- and (KAs4W40O140)27- with a 1/1 polyanion/cytochrome c ratio, and the smaller ion (SiW11O39)8- with a 2/1 ratio. Upon complexation, cytochrome c undergoes structural changes that are dependent on the size and charge of the polyanion, and on the pH and ionic strength of the medium. Three d...
Berghuis GA.The conception rates of semen intended for shipment and those of recently obtained semen are compared in the present paper. Conception rates using recently obtained semen were significantly superior to those obtained with semen intended for shipment. A number of factors to which this difference could be due are briefly discussed.
Sillerud CL, Bey RF, Ball M, Bistner SI.After the observation of 2 horses with uveitis on a horse farm in the Minnesota River valley, 100 horses from this geographic area were given ophthalmologic examinations and were evaluated serologically for leptospirosis. A statistically significant (P less than 0.001) association was observed between the finding of antibodies against Leptospira interrogans serovar pomona and uveitis.
Wyatt CR, Magnuson NS, Perryman LE.Six monoclonal antibodies, designated EqT2, EqT3, EqT6, EqT7, EqT12, and EqT13, which identify T lymphocyte antigens present at different stages of T cell maturation were used to examine T lymphocyte development in foals with severe combined immunodeficiency (SCID). Flow microfluorimetry demonstrated the presence of EqT12+ and EqT13+ prothymocytes and a few phenotypically mature EqT2+ and EqT3+ thymocytes within the thymic remnants of SCID foals. However, very few EqT6+ and EqT7+ resident cortical thymocytes were detected. The near absence of EqT6+ and EqT7+ cortical thymocytes was confirmed b...
Hodgson DR.This article reviews what are considered the basic concepts of gas transport, blood gases, and acid-base physiology is most mammalian species. Techniques for the appropriate collection of blood samples for blood gas and acid-base determinations in the newborn foal are described. Guidelines for interpretation of these values in the normal foal and those animals undergoing respiratory and metabolic derangements are provided.
Cox JH, DeBowes RM.Discomfort manifested by colic-like clinical signs in 2 young mares was presumed to be attributable to ovarian pain associated with follicular enlargement and ovulation. Diagnosis was based on the lack of detectable evidence of gastrointestinal disease, the finding of a large ovarian follicle or recent ovulation, the repetition of signs during several subsequent estrual periods, and the clinical response to pharmacologic suppression of estrus and ovulation. The similarity of the clinical signs in these 2 mares to cyclic intermenstrual pain in women was considered.
Payne SL, Fang FD, Liu CP, Dhruva BR, Rwambo P, Issel CJ, Montelaro RC.The extent and nature of genomic variation among nine antigenically distinct EIAV isolates recovered during sequential clinical episodes from two experimentally infected ponies were examined by restriction fragment analysis and nucleotide sequencing. Only minor variations in restriction enzyme patterns were observed among the viral genomes. In contrast, env gene sequences of four isolates from one pony revealed numerous clustered base substitutions. Divergence in env gene nucleotide and deduced amino acid sequences between pairs of virus isolates ranged from 0.62 to 3.4% env gene mutation rate...
Steffey EP, Hodgson DS, Dunlop CI, Miller MF, Woliner MJ, Heath RB, Grandy J.Hemodynamic and respiratory effects of 5 h of unvarying 1.57%, end-tidal (1.2 MAC) isoflurane in O2 anesthesia were characterized in ten left laterally recumbent horses. Compared to base line values at 30 min of constant dose isoflurane, cardiac output, hematocrit, total plasma solids, PaCO2, and peak inspired gas flow progressively and significantly (P less than 0.05) increased over the course of study. Arterial blood pressure increased (P less than 0.05) during the first 2 h of constant dose of isoflurane then decreased and remained near base line values. Inspiratory time progressively decre...
Cowell RL, Tyler RD, Clinkenbeard KD, MacAllister CG.This article discusses collection, slide preparation, culture technique, fluid analysis and evaluation, and cytologic evaluation of peritoneal and pleural effusions. The morphologic characteristics of various effusions are described, and the physical characteristics (volume, color, turbidity) of effusions are discussed. An algorithm for classifying effusions as transudates, modified transudates, or exudates is included, and each category is discussed.
Kannegieter NJ, Alley MR.A 20-month-old, Standard-bred colt was presented with an acute onset of hindlimb ataxia. Clinical and radiographic examination identified a compressive lesion affecting the spinal cord at the level of the 17th to 18th thoracic vertebrae. After euthanasia, post-mortem examination revealed a tumour in the epidural space, diagnosed histologically as a lymphosarcoma. Neoplastic lymphoid cells were also present in the abdominal lymph nodes and brain. Because of the disseminated nature of lymphosarcoma in the horse, involvement of the central nervous system is likely to be more common than is presen...
Satorov SS, Orzuev MI.Staphylococci occur in donkeys more frequently than in other animals, and only from donkeys coagulase-negative staphylococci, characteristic of humans (S. hominis, S. capitis, S. cohnii), were isolated. Least frequently staphylococcal carrier state was registered in cats; in these animals only coagulase-negative strains were found to occur. From 30 donkeys coagulase-positive staphylococci belonging to 47 S. aureus strains were isolated. These strains differed from known ecological variants in their biological properties, thus suggesting the existence of S. aureus ecovar specific for donkeys. T...
Labadia A, Rivera L, Costa G, García-Sacristán A.The presence of both alpha and beta adrenergic receptors in the caudal third ureter of the horse were studied in vitro under isometric conditions using adrenergic agonist and antagonist drugs. Isoprenaline and the beta 2- stimulating agent, salbutamol, elicited relaxation of the ureter smooth muscle strips. The responses were not affected by the beta 1- blocking agent, practolol, but were totally abolished by propranolol and the beta 2- blocking agent, butoxamine. The stimulation of alpha-adrenergic receptors with noradrenaline and phenylephrine evoked a contractile effect which was totally in...
Auer DE, Wilson RG, Groenendyk S, Filippich LJ.A case of pituitary dependent hyperadrenocorticism in a horse is reported. Clinical signs included hirsutism, polydipsia and general debility. The horse was persistently hyperglycaemic and glucose values were unchanged following subcutaneous administration of insulin. Resting cortisol values were normal, but dexamethasone suppression of cortisol concentration was shorter than normal. Plasma glucose, cortisol, insulin and glucagon concentrations were measured as part of an intravenous glucose tolerance test. The patient responses were different from those in a control pony.
Carpenter S, Evans LH, Sevoian M, Chesebro B.Equine infectious anemia virus was isolated from peripheral blood leukocytes collected during two early febrile cycles of an experimentally infected horse. RNase T1-resistant oligonucleotide fingerprint analyses indicated that the nucleotide sequences of the isolates differed by approximately 0.25% and that the differences appeared randomly distributed throughout the genome. Serum collected in the interval between virus isolations was able to distinguish the isolates by membrane immunofluorescence on live cells. However, no neutralizing antibody was detected in the interval between virus isola...
Illera JC, Illera M, Hamlin RL.Electrocardiograms were obtained from 100 male crossbred horses. In addition to standard limb leads, leads were taken from 12 points on the thorax. The QRS complexes were categorized into 1 of 8 forms on the basis of configuration and amplitudes of component deflections. Relative uniformity of QRS was determined for each lead, using the percentage of horses that possess a particular configuration. All unipolar thoracic leads, except those coplanar with the frontal plane, and lead aVR had great uniformity, with greater than 80% of the horses with a QRS of similar contour.
Roger T, Ruckebusch Y.The motor responses of the caecum and colon to stimulation of alpha 2-adrenoceptors by xylazine and detomidine at the recommended dose levels of 0.6 and 0.1 mg/kg were investigated in three ponies. The motor changes of the left ventral colon induced by continuous intra-arterial infusion of a prostaglandin (PGF2 alpha) were used to assess the relative inhibitory effects of xylazine and detomidine in a colic model. The administration of alpha 2-agonists inhibited the spiking activity on the whole of the large intestine for 20-30 min (xylazine) or 2-3 h (detomidine). However, the detomidine-induc...
Spensley MS, Carlson GP, Harrold D.During the growth interval encompassing age 2 days through 24 weeks, plasma, RBC, total blood, and extracellular fluid (ECF) volumes were determined in 7 healthy, resting foals. Evans blue dye and sodium thiocyanate were used to estimate plasma and ECF volumes, respectively. Absolute plasma volume remained stable from 2 days through 2 weeks of age, then increased progressively through 24 weeks of age. After decreasing between 2 days and 2 weeks of age, absolute RBC and total blood volumes progressively increased. Absolute ECF volume increased progressively from 2 days of age through 24 weeks o...
Tyler RD, Cowell RL, Clinkenbeard KD, MacAllister CG.Normal reference ranges and pertinent background information on equine hematology are presented and briefly discussed. Diagnostic interpretation of hematologic data is discussed and three diagnostic algorithms and two diagnostic tables are provided to facilitate the use of the presented information for diagnosis. Two cases are presented and the information presented in the article is used to interpret the case data.
de Waal DT, Potgieter FT.Rhipicephalus evertsi evertsi larvae were fed on the ears of rabbits. Seven days after larval infestation, unfed, newly moulted nymphae were manually removed to infest a splenectomized donkey showing a patent Babesia caballi infection. Engorged nymphae were collected from the donkey and the ensuing adult ticks were placed on a susceptible horse. The horse contracted a B. caballi infection showing a prepatent period of 19 days after tick infestation. A very low parasitaemia, (highest score 2), which was patent for only 10 days, was recorded. The lowest packed cell volume recorded was 16%.
van Dijk J.Jan van Dijk, RCVS specialist in veterinary parasitology, describes how data can be used to both increase understanding of trends in equine helminth abundance and drive better treatment of individual horses.
Alberti E, Stucchi L, Lo Feudo CM, Ferrucci F, Zucca E.Pulmonary artery stiffness (PAS) is an index of pulmonary artery elasticity that permits to evaluate the pulmonary vascular bed in humans. It can early detect an increase in pulmonary artery stiffness as a consequence of remodeling of the vessel wall caused by chronic pulmonary and congenital heart diseases. This remodeling can occur also in horses with chronic respiratory diseases. Thus, PAS could be a useful echocardiographic parameter also in horses. However, in literature, there are no studies regarding PAS in horses. The aim of this study is to evaluate the feasibility of PAS in horses. F...
Bartmann CP, Schiemann V.Diagnostic and operative hysteroscopy have offered an advance in equine fertility diagnostic and equine fertility surgery. A distension of the uterine cavity and an establishment of a continuous intrauterine pressure are basic requirements for complete visualisation of intrauterine structures and safe and efficient surgical procedures. Superelevated pressure and resorption of distension media may result in fatal complications. Intrauterine pressure was monitored in 28 healthy di- or anestrus mares during hysteroscopy via a transcervically inserted catheter. Mares were sedated with xylazine and...
Irwin DH, Howell DW."Cube colic" is described and vain attempts to cause the problem on an experimental basis are recorded. It is concluded that not all horses are susceptible to cube colic and if colic occurs in horses being fed on cubes, it is not necessarily due to feeding of cubes. Nomenclature of bowel disorders is considered.
Rodriguez ML, McConnell I, Lamont J, Campbell J, FitzGerald SP.A generic, rapid and sensitive enzyme linked immunosorbent assay (ELISA) test has been developed which allows large-scale simultaneous testing of synthetic corticosteroids viz., flumethasone, dexamethasone and betamethasone. This assay can be directly applied to diluted urine samples (1 + 9) without hydrolysis of glucuronide or sulfate conjugates or any other treatment of samples. The polyclonal antibody was obtained by immunizing sheep with a flumethasone derivative linked to human serum albumin. This polyclonal antibody displayed high-reactivity with several synthetic corticosteroids whilst ...
Smith AV, Wilson C, McComb K, Proops L.In the original publication, data availability text was incorrectly published. The correct text should read as below.
Koterba AM, Drummond WH, Kosch P.The basic concepts of diagnosis and treatment in the abnormal neonatal foal are presented. Methods of restraint, sedation, and general nursing care are discussed, as well as more specific techniques of respiratory and circulatory system support.
Hildebrand SV, Arpin D, Cardinet G.Biopsy specimens of the cutaneous omobrachialis muscle were obtained from 10 horses with a problem of myositis from mild exercise. One horse had been evaluated previously and malignant hyperthermia-like contractures developed in its muscle biopsy specimen during the contracture test. In this study, the halothane-caffeine contracture test and histologic and histochemical evaluations were performed on muscle biopsy specimens. In the contracture test, no muscle biopsy specimen developed contracture in the presence of 2 or 4% halothane alone. The mean (+/- SEM) caffeine-specific concentration in t...
Gasthuys F, de Moor A, Parmentier D.Haemodynamic and respiratory responses to halothane were investigated in dorsally recumbent, ventilated ponies during 2 hours. Normocapnia was maintained using intermittent positive pressure ventilation. Compared to the base line values at 30 minutes of constant dose halothane, no significant changes in heart rate, systemic blood pressure, cardiac output, cardiac index, stroke volume and left ventricle work were observed during a 2 hours anaesthesia. Arterial oxygenation increased initially (greater than 300 mm Hg) but tended to decrease non-significantly during the rest of the anaesthesia. Bl...
Belz JP, Glatzel PS.Because of the mare's ability to conceive very soon post partum a thoroughly performed control of the puerperal period is of particular importance. Cytological examinations of uterine content and histological examinations of uterine biopsy specimens provide more detailed information than microbiological examinations of uterine swabs. Uterine content and uterus biopsy specimens of 55 mares were examined histologically on days 3, 6 and 9 post partum. We observed a heavy polymorphonuclear reaction of the endometrium following disturbed puerperal processes especially in cases of retained placenta....
van Amstel SR, Reyers F, Colly PA.Variable results were obtained when the starch digestion test was carried out on a suspected case of malassimilation in a horse. In order to re-evaluate this test, 15 starch digestion tests were carried out using 4 horses. Results showed a marked variation in the increase in plasma glucose levels between individual horses and especially between poor and good condition horses when the dose of starch was based on body mass. Results also suggest that a fixed dose of starch may give more consistent results.
Summers PM, Wells KE, Adkins KF.The features of an ossifying ameloblastoma in a 5-year-old gelding are described. The tumour developed in the angle of the right mandible and microscopically consisted of multiple follicles and islands of epithelial tissue adjacent to which were trabeculae of bone, osteoid and compact collagenous tissue.
Splitter GA, Incefy G, Iwata T, McGuire TC.Arabian horses with severe combined immunodeficiency disease (SCID) were evaluated for thymic hormone activities using thymic extracts and sera. Extracts prepared from thymus of SCID horses were able to increase the number of spleen cells responding to sheep red blood cells in irradiated, bone marrow-reconstituted mice. In addition, ultrafiltrates prepared from sera of these immunodeficient horses, which contained material with molecular weight of less than 50,000 Daltons could (a) induce a population of human bone marrow precursor cells to differentiate into cells bearing SRBC receptors and f...
Ketzner KM, Stewart AA, Byron CR, Stewart M, Gaughan EM, Vanharreveld PD, Lillich JD.Describe the use of a phalangeal cast as treatment for wounds in the pastern and foot region of horses. Secondly, to evaluate the healing and soundness of horses treated with phalangeal casts. Methods: Retrospective study of 49 horses. Procedures Medical records of 49 horses that were treated with a phalangeal cast for 50 cases of wounds in the pastern and foot region at equine referral hospitals from 1995 to 2006 were reviewed and follow-up information was obtained. Results: Treatment consisted of wound debridement, lavage, wound closure (28 wounds), cast application and antibiotics (84%). At...
Delbeke FT, Landuyt J, Debackere M.Concentrations of the non-steroidal anti-inflammatory drug (NSAID) alclofenac were determined by a sensitive high performance liquid chromatographic procedure in plasma and urine of horses following oral administration of a dose of 3 g. In plasma, alclofenac was present in detectable concentrations for 72 h. The plasma disposition in individual horses was best described by a bi-compartmental model with two successive rate constants ka1 = 0.05 +/- 0.06 h-1 and ka2 = 0.06 +/- 0.01 h-1. Alclofenac half-lives t1/2 alpha and t1/2 beta were 1.0 +/- 0.8 h and 6.9 +/- 1.5 h, respectively. Maximal conc...
Tschudi P.The cardiac arrhythmias, classified in disturbances of impulse formation and conduction disturbances, their genesis and clinical significance are described and illustrated with electrocardiograms, registered with the bipolar chest leads.