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.
Broquist HP, Mason PS, Hagler WM, Harris TM.When infested with the fungus Rhizoctonia leguminicola, certain forages, e.g., red clover hay, can cause a "slobber syndrome" of varying severity when consumed by ruminants. The causative agent has been presumed to be slaframine [(1S,6S,8aS)-1-acetoxy-6-aminooctahydroindolizine], which is produced by R. leguminicola. In one serious outbreak of the slobber syndrome in horses, the red clover forage involved was carefully examined and found to contain R. leguminicola and slaframine. An identical hay sample is shown here by ion-exchange chromatographic and gas chromatographic-mass spectrometric an...
Bailey JV, Barber SM, Fretz PB, Jacobs KA.The records of 13 horses of various breeds with subluxation of the radiocarpal, intercarpal or carpometacarpal joint, or combinations of these were reviewed. Subluxation was most common at the carpometacarpal joint (n = 10) and concomitant fractures of individual carpal bones or metacarpus II and IV were seen (n = 12).Treatment comprised of immobilization in a full leg plaster cast for from four to 18 weeks. Three animals were euthanized, two because of cast complications and one because of a request by the owner. The remaining ten were saved to function as breeding animals.
Duncan SG, Reed SM.In horses with large bowel disease, those with circulating endotoxins but no evidence of altered hemostasis had a good prognosis for survival. Those with circulating endotoxins and evidence of altered hemostasis (fibrin degradation products) had a poor prognosis. Portal vein infusion of endotoxins over 24 hours caused hoof discomfort, evidenced by shifting of weight and standing with all 4 feet together, and a decreased hoof temperature. Clinical signs appeared within 30 minutes of initiation of infusion and subsided within 4 hours despite continued infusion. Long-term heparin therapy results ...
Klei TR, Torbert B, Chapman MR, Foil L.Microfilariae of Onchocerca cervicalis were detected in midventral skin biopsy samples in 64 of 84 (76%) mixed-breed ponies greater than 2 years old from the Gulf Coast area and in 42 of 51 (82.4%) horses from Louisiana breeding herds. The number of microfilariae per 8 mm of biopsied skin (ponies) ranged from 1 to 21,570. The number of microfilariae per 6 mm of biopsied skin (horses) ranged from 8 to 55,600.
Payne S, Parekh B, Montelaro RC, Issel CJ.The unique periodic nature of equine infectious anaemia (EIA) is believed to result from the ability of the infecting virus. EIAV, to undergo relatively rapid antigenic variations which circumvent host immune responses resulting in distinct virus populations in sequential clinical episodes in the persistently infected horse. This model was examined by oligonucleotide mapping comparisons of the RNA genomes of selected isolates of EIAV. Variations in oligonucleotide maps could be reproducibly demonstrated (i) after adaptation of the laboratory strain of EIAV to replication in a pony, (ii) after ...
The importance of the horse industry to the economy of the United States and the impact of parasitic infections on the industry are well documented. However, contemporary research activity on internal parasites of horses has not kept pace with growth of the horse population. Parasitic infections are a major facet of enteritis and colic in horses. Parasites are also associated with poor growth and development, respiratory tract disease, dermatitis, and CNS lesions. Babesia infections remain a threat to horses imported from some regions of the world. Most research activity has dealt with the dev...
Meijler FL, Kroneman J, van der Tweel I, Herbschleb JN, Heethaar RM, Borst C.RR interval sequences during spontaneous atrial fibrillation in eight horses were analyzed as in previous studies in patients and dogs using histograms and serial auto-correlograms. In patients and dogs with spontaneous atrial fibrillation, ventricular rhythms were always random. In the horses, the histograms were skewed with median RR intervals of approximately 1,000 ms. A striking finding in these animals was the presence of long RR intervals up to 5,000 ms in duration. The shortest RR intervals lasted 400 to 600 ms. In contrast to findings in dogs and patients, the serial autocorrelograms s...
Montelaro RC, West M, Issel CJ.The immunogenic contributions of the carbohydrate and peptide portions of the major envelope glycoprotein of equine infections anemia virus, EIAV gp90, were analyzed by measuring the effects of specific glycosidase and protease digestions on the reactivity of the glycoprotein with immune sera from infected horses. The results of both direct and competitive radioimmunoassay demonstrated that immune sera contained antibodies reactive with both the carbohydrate and protein moieties of EIAV gp90, with the predominant reactivity apparently against the gp90 peptide epitopes. These results contrast w...
Donecker JM, Bramlage LR, Gabel AA.Twenty-nine fractures of the olecranon process of the ulna in horses treated at The Ohio State University College of Veterinary Medicine from 1973 through 1983 were evaluated. The objectives of the study were to determine the prognosis for various configurations of fractures of the olecranon process of the ulna, to determine what preoperative factors influenced the prognosis, and to evaluate the efficacy of the treatment methods used. The fractures were placed in one of 4 categories on the basis of severity of the injury: type-1 fractures involved the physeal plate; type-2 fractures involved t...
Sweeney CR, Soma LR.Of 61 horses with a history of exercise-induced pulmonary hemorrhage and treated with furosemide 4 hours prior to racing, 34 (55.7%) continued to bleed. Of 24 horses with exercise-induced pulmonary hemorrhage that were not treated with furosemide prior to racing, 17 (70.8%) still bled. There was no statistically significant difference between the treated and the nontreated groups. Of 45 horses given hesperidin-citrus bioflavinoids, 38 (84.4%) bled when exercised 90 days later. There was no statistically significant difference between the results for hesperidin-citrus bioflavinoid-treated horse...
Colahan PT, Peyton LC, Connelly MR, Peterson R.Twenty-three isolations of Serratia spp were made from 21 horses at the University of Florida Veterinary Medical Teaching Hospital between Jan 1, 1979 and July 1, 1983. Three Serratia spp were involved in single-organism and mixed infections of various tissues. Eight horses of this group died. All horses that died had massive, mixed, gram-negative infection. The other 13 responded to treatment, including systemic antibiotic therapy. Most of these horses were stressed and under antibiotic therapy prior to the time of culture. Possible nosocomial infection, variable antibiotic sensitivity, and a...
Myer YP, Kumar S.The ascorbate reduction of horse heart ferricytochrome c in 0.05 M phosphate + 0.25 M sodium sulfate, at pH 7.3, as a function of temperature, 12-36 degrees C, and at alkaline pH 8.4 using stopped flow technique has been examined. The data have been analyzed in terms of a two-step mechanism, binding followed by reduction (Myer, Y.P., Thallam, K.K., and Pande, A. (1980) J. Biol. Chem. 255, 9666-9673). At neutral pH and up to about 26 degrees C, the first order reduction constant is independent of temperature, i.e. with zero or near-zero activation energy. At higher temperatures, it becomes temp...
Clemmons RM, Dorsey-Lee MR, Gorman NT, Sturtevant FC.Whole blood platelet counts, coagulation profiles and in vitro platelet function tests were monitored in newborn foals during the first week of life. Platelet counts, mean platelet volumes and thrombin-induced malondialdehyde production were not different from adult mares. Prothrombin and partial thromboplastin times were slightly, but not significantly, longer for neonatal blood samples than for mare samples. Platelet aggregation responses to serotonin, arachidonic acid or adrenaline did not change during the study. On the other hand, adenosine diphosphate-induced aggregation and collagen-ind...
Rossdale PD, Ousey JC, Dudan FE, Leadon DP, Cash RS, Reddy R, Silver M, Fowden A, Broughton Pipkin F, Jeffcott LB.This paper describes the general management of mares and foals during the perinatal period and the methodology used in a collaborative research project on equine prematurity. Sixteen mares with dated pregnancies delivered 45 foals over three breeding seasons (1981 to 1983). In the majority, parturition was induced with oxytocin and/or fluprostenol; the remainder were allowed to foal spontaneously. Pre-colostral milk analysis provided a means of assessing the pre-foaling status of the mare. All were observed and monitored before, during and after parturition and the sampling protocol for both m...
Silver M.THERE is no shortage of anatomical information on the equine foetus and its placenta, from the early work of Ruini in the 16th century to the recent studies of Steven and colleagues (Steven 1982); by contrast, knowledge of the physiology of the foal in utero is sparse. In other domestic animals there have been considerable ads ances in foetal and neonatal physiology and endocrinology in recent years due mainly to the develop-ment of the chronically catheterised foetal preparation in which sequential observations can he made in the conscious animal (Silver 1981). Some information about the deve...
Meschter CL, Maylin GA, Krook L.Three mature Thoroughbred geldings were given 13.63 mg phenylbutazone/Kg bodyweight intravenously for 3 days and repeated in one horse 4 days later. After 4, 7 and 10 days (double treatment), degeneration of the wall of small veins occurred in all horses. The veins were dilated and/or showed hyalin degeneration. The phlebopathy was interpreted to be paramount in phenylbutazone intoxication. All other manifestations, including erythro- and leukodiapedesis, submucosal edema and ulceration of the gastrointestinal mucosa, phlebothrombosis and significant changes in the hemogram and serum chemistry...
Palmer AC, Leadon DP, Rossdale PD, Jeffcott LB.A neuropathological examination was carried out on the brains of 58 foals. Forty-two were pony foals induced at various periods of gestation from 200 days onwards. Two were pre-viable pony foals delivered by caesarean section and 14 were Thoroughbred foals (one set of twins, two stillborn, five premature, two dysmature, two convulsive and one induced). The only significant pathological change involved intracranial haemorrhage. Subarachnoid haemorrhage occurred in all of 10 pony foals induced before 301 days of gestation and in two pony foals born by caesarean section at 270 and 280 days gestat...
Ousey JC, Dudan FE, Rossdale PD, Silver M.The effectiveness of the prostaglandin F analogue fluprostenol in inducing labour in the mare was examined by giving sequential injections over the last 50 days of gestation. The behavioural and endocrine changes elicited by the drug in pregnant and non-pregnant animals and in foals were also studied. Fluprostenol (250 or 500 micrograms intramuscularly) failed to induce labour before 320 days gestation; thereafter its effect was capricious. Twelve mares foaled 1 to 36 h after the last test; eight delivered normal, viable, apparently 'term' foals and four produced stillborn/premature animals. E...
Campbell TM, Studdert MJ.Severe combined immunodeficiency disease (SCID) in foals is the only known animal model for the autosomal recessive form of primary SCID in man. A major requirement in the treatment of SCID is the maintenance of the patient in a disease free state until definitive therapy can be undertaken. This paper reviews the current status of prophylactic and definitive therapy in man and the horse. Particular emphasis is placed on the methods of reconstitution available, involving foetal tissues and bone marrow.
Colbourne CM, Rosenstein DS, Steficek BA, Yovich JV, Stick JA.A progressive ethmoidal hematoma (PEH) was treated successfully in a 4-week-old Belgian filly by surgical removal, using a frontonasal bone flap. The filly had respiratory stridor, epistaxis, and facial enlargement over the left paranasal sinuses, which had progressively increased in size since birth. Computed tomographic images of the head obtained with the foal under general anesthesia were useful in determining the extent and nature of the soft-tissue mass and planning surgical intervention. On the basis of the histologic appearance of the mass, a diagnosis of PEH was made. Twelve months af...
Goethals J, Nikolayev D, Thielens A, Vermeeren G, Verloock L, Deruyck M, Martens L, Joseph W.This paper describes the exploration of the combined antenna-channel model for a horse hoof. An antenna of 25 mm × 40 mm is designed in the ISM 868 MHz band. During the characterization and design of the antenna, the dynamic and harsh environment of the horse hoof is taken into account throughout every step of the procedure because it is impossible to de-embed the antenna from its environment. The antenna and channel model are verified extensively by measurements in phantom and ex vivo. The antenna is verified to be robust against changes in the morphology of the horse's hoof up to 50%. The d...
Campbell NB, Jones SL, Blikslager AT.A potential adverse effect of cyclo-oxygenase (COX) inhibitors (nonsteroidal anti-inflammatory drugs [NSAIDs]) in horses is colitis. In addition, we have previously shown an important role for COX-produced prostanoids in recovery of ischaemic-injured equine jejunum. It was hypothesised that the nonselective COX inhibitor flunixin would retard repair of bile-injured colon by preventing production of reparative prostaglandins, whereas the selective COX-2 inhibitor, etodolac would not inhibit repair as a result of continued COX-1 activity. Segments of the pelvic flexure were exposed to 1.5 mmol/l...
Mollett TA, Elmore RG, Blanchard TL, Berg JN.This study was conducted to determine if Escherichia coli endotoxin was absorbed from the equine uterus and if exogenous progesterone and estrogen affected the absorption of intrauterine endotoxin. Six mature anestrous pony mares were used in three consecutive crossover experiments (Periods) with a 14 day recovery between each period. Mares were randomly assigned to one of two treatment groups (three mares per group) and received an intrauterine infusion of either saline or endotoxin. Treatment groups were reversed and readministered after 14 days completing a crossover design (Period 1). Duri...
Caldwell M, Hathcock T, Brock KV.In this study, equine source polyclonal anti-Bacillus anthracis immunoglobulins were generated and utilized to demonstrate passive protection of mice in a lethal challenge assay. Four horses were hyper-immunized with B. anthracis Sterne strain for approximately one year. The geometric mean anti-PA titer in the horses at maximal response following immunization was 1:77,936 (Log2 mean titer 16.25, SEM ± 0.25 95% CI [15.5 -17.0]). The geometric mean neutralizing titer at maximal response was 1:128 (Log2 mean titer 7, SEM ± 0.0, 95% CI 7). Treatment with hyper-immune plasma or purified immun...
Sandler GA, Scott EA.Vascular responses occurring with pneumatic tourniquet application were evaluated in the equine thoracic limb. Recordings of pressure (arterial and venous) and flow (arterial) distal to the tourniquet were made for 60 minutes. Reactive hyperemia was observed; however the increased flow was neither of a sufficient duration nor of a great enough volume for total repayment of flow loss.
Steffey EP, Willits N, Wong P, Hildebrand SV, Wheat JD, Meagher DM, Hodgson D, Pascoe JR, Heath RB, Dunlop C.Fifty-eight foals were divided into two groups for study of aspects of the clinical anesthetic management of foals and to characterize effects of halothane (n = 30) and isoflurane (n = 28) in foals. There were no significant differences (P greater than 0.05) in the demographics of the two groups. Results of hemograms and biochemical analysis of venous blood samples before and after anesthesia were either not influenced or only mildly (clinically unimportant) affected by either agent. Like adult horses, foals have an increased PaCO2 when anesthetized with inhaled anesthetics. We could detect no...
Beatriz FR, Marta VG, María MC, Joaquín JF, Esther DF, Luis-Javier EC, Gabriel MD, Manuel IG.An 8-year-old mare mule was presented with a facial mass and history of anorexia, unilateral epistaxis and purulent nasal discharge. The facial mass was encountered from the ventral to the lateral right canthus of the eye up to the facial crest. Thoracic ultrasonography showed five rounded masses. A standing CT under sedation was performed revealing a huge extension and infiltration on surrounding tissues. Due to the extension, type of lesions, outcome and suspicion of metastasis, the owner chose to euthanize the patient. Necropsy confirmed the presence of tumoral lesions spread into the lungs...
Mogielnicka-Brzozowska M, Woźniak MJ, Cichowska AW, Fraser L, Kraziński B, Strzezek R, Zielińska D.Seminal plasma (SP) proteins are responsible for sperm functional quality. Developing a reliable method to determine the degree of oxidative damage of these proteins is important for establishing semen fertilizing ability. The main aim of the study was to verify the applicability of protein carbonyl derivatives measurement in the SP of canine and stallion, using a method with 2,4-dinitrophenylhydrazine (DNPH). The research material consisted of ejaculates obtained from eight English Springer Spaniels, and from seven half-blood stallions during the breeding and non-breeding season. The content ...
Firth EC.Detecting changes in bone during growth, training, rest from competition (spelling), and disease in horses requires imaging techniques that have a high level of accuracy and precision. Currently, most imaging techniques used in horses do not possess such characteristics and are more suitable for detecting end-stage disease than subtle changes. Some are incapable of detecting changes in bone size. Non-planar techniques should be used for estimating or determining bone strength. This review outlines available imaging techniques and shows why cross-sectional procedures are required to accurately ...
Inoue OJ, Freeman DE, Wallig M.To study effects of hypochlorous acid (HOCl) on equine colonic mucosa in vitro, and determine whether addition of ascorbic acid protects against the effects. Methods: 6 healthy horses and ponies. Methods: Short-circuit current was measured in mucosa mounted in Ussing chambers. Incubation conditions were: control (no additions); 5 mM HOCl; 1 mM HOCl; same and 5 mM ascorbic acid; 3 mM HOCl; 3 mM HOCl and 5 mM ascorbic acid; 7 mM HOCl; and 7 mM HOCl plus 5 mM ascorbic acid. Permeability was measured with [3H]mannitol and, at the conclusion of each experiment, tissues were examined microscopically...
Watt BC, Foerner JJ, Haines GR.To describe incomplete oblique sagittal dorsal cortical fractures of the equine third metacarpal bone, their surgical repair, and subsequent performance of the horses. Methods: Retrospective examination of medical records and racing performance. Methods: Six Thoroughbred race horses, 2 to 4 years of age. Methods: Radiographic confirmation of all fractures preceded general anesthesia and surgical correction. Three fractures were treated by intracortical compression using screws placed in lag fashion, and five fractures were treated by osteostixis. Race records were reviewed for each horse to de...
White ME.A complete listing of the clinical signs and diseases of dogs, cats, horses, cattle, sheep, goats and swine in the CONSULTANT database for computer assisted diagnosis is presented, along with the codes used to record this data. This list may be useful to those teaching, researching or writing on the diseases of domestic animals, and is of particular use to those who need such a resource for developing diagnostic coding and computer-assisted information retrieval.