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.
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.
Morse CC, Saik JE, Richardson DW, Fetter AW.Benign proliferative fibro-osseous lesions of the rostral mandible in six young horses are classified as equine juvenile mandibular ossifying fibroma. Histologically there is a characteristic abrupt transition from subgingival fibroblastic stroma to a zone of proliferating osteoblasts that form irregular spicules of osteoid. The layer of proliferating osteoblasts blends with a deeper zone of bony trabeculae rimmed by osteoblasts and separated by intertrabecular spaces of moderate cellular density. Incomplete surgical excision resulted in local recurrence, while rostral mandibulectomies resulte...
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...
Vanselow BA, Abetz I, Jackson AR.Of 61 horses with sarcoids treated with intralesional injection of a double emulsion incorporating inactivated bacillus Calmette Guérin organisms, 36 (59 per cent) showed complete regression and 11 (18 per cent) showed partial regression. The majority of cases required only one treatment. Not all sarcoids were responsive to this therapy; those not responding were usually large or on horses with multiple sarcoids.
Prescott JF, Staempfli HR, Barker IK, Bettoni R, Delaney K.Severe colitis was induced in two ponies after oral pretreatment with clindamycin and lincomycin, followed by intestinal content from two horses which had died from naturally-occurring idiopathic colitis. Two ponies treated with antibiotic alone, and two ponies treated with intestinal content alone, were unaffected. In a further study, three ponies treated on separate occasions with lincomycin, administered orally, died or were destroyed 67 to 72 h after initial treatment. No established salmonella, yersinia or campylobacter pathogens were isolated from these ponies, but a clostridium closely ...
Haluska GJ, Currie WB.Concentrations of plasma progesterone were similar to values reported in the literature except that a significant decrease in progesterone during the last day, but before parturition, was detected by systematic, high-intensity blood sampling. Mean concentrations of oestradiol-17 beta increased sharply and significantly, plateaued for 132.8 +/- 1.5 days (mean +/- s.e.m., N = 9), then declined sharply in each mare. There was obvious variation between the mares in when these increases and decreases in oestradiol-17 beta occurred, with the events being related closely to ambient photoperiod condit...
Sangiah S, McAllister CC, Amouzadeh HR.The basal gastric pH, free and total acid contents from five adult horses were determined at two-hour intervals for six- to eight-hour periods. The basal gastric pH, free and total acid contents varied from 2.14 +/- 0.08 to 2.41 +/- 0.14, 28.63 +/- 8.27 to 17.89 +/- 2.86 mmol litre-1 and 41.38 +/- 9.72 to 37.38 +/- 3.70 mmol litre-1, respectively. Cimetidine (8.8 mg kg-1 orally) and ranitidine (2.2 mg kg-1 orally) increased the basal gastric pH to above 3.6 (P less than 0.05) with a concomitant reduction of 75 per cent and 75 to 100 per cent in the basal gastric free acid content, respectively...
Gutiérrez JM, Chaves F, Rojas E, Elizondo J, Avila C, Cerdas L.A monovalent antivenom was produced by immunizing two horses with venom of the pit viper Bothrops asper (Ophidia: Viperidae). Although development of the immune response against four toxic and enzymatic activities of the venom was similar in both horses during the first two thirds of the immunization schedule, antibody response in one of the horses reached much higher levels in the last part of the immunization. Immunoelectrophoretic analysis indicates that there were precipitating antibodies in the sera of these horses during all the stages of immunization. However, immunoprecipitation did no...
Mäenpää PE, Pirskanen A, Koskinen E.Serum alkaline phosphatase activity and serum concentrations of osteocalcin, free thyroxine, protein, and cholesterol were measured in 14 foals monthly from birth to 1 year of age. A transient decrease (P less than 0.05) in alkaline phosphatase activity and osteocalcin, free thyroxine, and cholesterol concentrations was found in November after transferring the horses from pasture to stables for the winter months. During the 2 subsequent months, serum alkaline phosphatase activity and osteocalcin concentration increased slightly. Protein concentration was highest in late fall and decreased (P l...
Braverman Y.Six hundred and twenty culicoides of five species were collected from a bait horse at Kannot, Israel, between April and September 1986. Seventy-two per cent of the midges were collected from the belly and 27 per cent from the dorsal aspect of the body, ie, the sweet itch summer seasonal recurrent dermatitis (SSRD) zone. Midges were active mainly from half an hour prior to half an hour after sunset. Only Culicoides puncticollis, C imicola and C schultzei group were collected in considerable numbers. While C imicola was present continuously throughout the season, the appearance of the two other ...
Fitzgerald BP, Mellbye LB.Two experiments were performed to test the hypothesis that the seasonal suppression of gonadotrophin pulse frequency in anoestrous horse mares reflects inhibitory neural mechanisms. In a preliminary experiment (Exp. 1) conducted in February, 4 anoestrous mares were sedated by repeated intravenous injections of xylazine, an alpha 2-adrenergic receptor agonist. On the day of treatment, 1-2 LH pulses were observed in xylazine-treated mares. In contrast, during a 12-h period only 1/8 untreated control mares exhibited a LH pulse. In Exp. 2, the effect of xylazine-induced sedation on pulsatile gonad...
Turner AS, Yovich JV, White NA, Embertson RE, Santschi EM, Slone DE.A retrospective study was performed to evaluate the healing of ventral midline abdominal incisions, closed with a simple continuous suture pattern using absorbable suture material, in 139 horses and foals. Dehiscence and incisional hernia developed separately in two horses. The low incidence of dehiscence and incisional hernia, compared with their reported incidence following the use of interrupted suture repair, leads the authors to recommend this alternative method of abdominal incision closure in horses. The security of closure is not sacrificed and the advantages of a rapid closure are des...
Hubbell JA, Reed SM, Myer CW, Muir WW.The records of 131 horses undergoing general anaesthesia and positive contrast cervical myelography with metrizamide were examined to determine the effect of the procedure on the 'patient'. Three per cent of minimally ataxic and moderately ataxic horses had serious complications after myelography. Thirty-two per cent of severely ataxic horses died or were destroyed after general anaesthesia and myelography. Although general anaesthesia and myelography are essential components of a complete neurological evaluation of a horse, they impose a significant risk.
Benanchi PL, Gazzei G, Giannozzi A.A simple two-step procedure for purifying F(ab)2 fragments of horse immunoglobulins is described. In the first step, the horse plasma is diluted, made up to 12% (w/v) with ammonium sulphate and digested with pepsin. In the second step, the previously dialyzed solution is chromatographed. Instead of a normal ion-exchange resin, a DEAE-cellulose, covalently linked to a synthetic vinyl polymer, was used (DEAE-Zeta-Prep). With this assembly it is possible to perform chromatography at a high flow-rate without the problems related to the use of large columns. The yield and purity of the final produc...
Specht TE, Nixon AJ, Colahan PT, Moore BG, Brown MP.Four horses with subchondral cyst-like lesions in the medial radial facet of the distal portion of the radius were examined. Joint effusion and signs of pain from flexion of the antebrachiocarpal joint were not observed, but lameness was observed in 3 of the 4 horses. Regional nerve blocks and intra-articular anesthesia were used to localize the lesions, and conservative treatment resulted in soundness for performance.
Cornick JL, Carter GK, Bridges CH.Chronic hepatic disease was diagnosed in 6 horses with history of anorexia and weight loss. These horses consistently had abnormally high serum gamma-glutamyltransferase activities, total and direct bilirubin and blood ammonia values, and sulfobromophthalein clearance times, whereas serum iditol dehydrogenase, aspartate transaminase, and alkaline phosphatase activities were variable. In the 6 horses, histologic examination of the liver revealed lesions of chronic hepatitis with varying degrees of fibrosis. All 6 horses had ingested kleingrass (Panicum coloratum) for variable periods. Three hea...
Arden WA, Stick JA.To determine the reliability with which inorganic phosphorus (phosphate) concentrations can be used to predict major intestinal injury associated with equine colic, phosphate concentrations were measured in serum, peritoneal fluid, or both from 9 clinically normal adult horses (group A), 37 horses successfully managed medically for signs of abdominal pain (group B), 26 horses with signs of abdominal pain and undergoing exploratory laparotomy without intestinal resection (group C), and 26 horses undergoing intestinal resection or euthanasia for extensive intestinal lesions (group D). Peritoneal...
Lloyd KC, Peterson PR, Wheat JD, Ryan AE, Clark JH.The diagnosis of keratoma in 7 horses and their treatment and outcome were evaluated. Horses were 2 to 20 years old, of various breeds, and were intact or castrated males. All were lame, and 6 horses had had previous injuries of the affected hoof that had not responded to prior treatments. Only 1 hoof was affected in each horse. Keratomas were beneath the hoof wall (6 horses) or sole (1 horse). Radiographically, a circular or semicircular defect with a discrete margin was present in the distal portion of the third phalanx in 3 horses. Grossly, keratomas were firm solitary masses (1.5 to 5 cm d...
Frazer GS, Robertson JT, Boyce RW.A 5-year-old Appaloosa mare had a history of mild intermittent abdominal discomfort and clinical signs that were suggestive of intestinal obstruction. Palpation per rectum revealed a large mass attached to the left uterine horn, with smaller masses extending dorsally and cranially and causing constriction of the rectum. At necropsy, numerous multilobulated masses were observed in the abdominal cavity and several nodules were seen in the lungs. The left ovary was large and contained both cartilage and hairlike material. Sections from all masses had similar histologic features and confirmed the ...
Grzeskowiak RM, Barrett EJ, Rodgerson DH.An 11-year-old Thoroughbred mare with colic unresponsive to medical treatment underwent exploratory laparotomy. During surgery the cecum was found entrapped within the epiploic foramen from left to right. The entrapped cecum was reduced through the foramen by gentle traction. After reduction of the cecum, rupture of the portal vein was detected. Loss of a large amount of blood prompted euthanasia during surgery. Une jument Thoroughbred âgée de 11 ans atteinte de coliques ne répondant pas au traitement médical a subi une laparatomie exploratoire. Durant la chirurgie, le cæcum a été trou...
Lewis DD.A classification scheme for penetrating joint injuries is presented. Diagnostic techniques and treatment recommendations for managing penetrating joint injuries in small animals are described. Techniques used in human and equine patients are discussed for comparison.
Gift LJ, DeBowes RM.Nonhealing wounds can present a frustrating clinical challenge to the veterinary practitioner. In many cases, healing is delayed by the presence of a foreign body or sequestrum; a review of wounds complicated by the presence of osseous sequestration and penetrating foreign bodies is presented. The typical signs include delayed wound healing and the presence of serous to exudative drainage, which may vary from intermittent to continuous. The use of radiographic or sonographic imaging modalities is often of value in reaching a diagnosis. Removal of the sequestra or foreign body is generally cura...
Townsend WM, Langohr IM, Mouney MC, Moore GE.Based on the current literature, neither medical, surgical nor combination therapy adequately controls equine glaucoma for many horses. Aqueous shunts have been useful in other species to control glaucoma. Objective: To determine whether aqueous shunts in normal equine eyes significantly reduce intraocular pressure (IOP) without causing vision threatening complications. Methods: Prospective experimental trial. Methods: Aqueous shunts were placed in 7 normal eyes of 4 horses. The shunts were placed dorsotemporally. Examinations were initially performed daily for 7 days and after that every 3 da...
Gaynor JS, Bednarski RM, Muir WW.The effect of xylazine on the arrhythmogenic dose of epinephrine (ADE) was studied in 9 horses. Anesthesia was induced by administration of guaifenesin (50 mg/kg of body weight, IV) followed by thiamylal (4 to 6 mg/kg, IV) and was maintained at 1 minimal alveolar concentration (MAC) of halothane (0.89%). Base apex ECG and facial artery pressure were recorded. Epinephrine was infused in a sequence of arithmetically spaced increasing rates (initial rate 0.25 micrograms/kg/min) for a maximum of 10 minutes. The ADE was defined as the lowest epinephrine infusion rate to the nearest 0.25 micrograms/...
Thompson DL, Reville-Moroz SI, Derrick DJ, Walker MP.Sixteen intact cyclic mares were treated on the fourth day of estrus and then every other day for a total of six injections with 1) testosterone propionate, 2) dihydrotestosterone (DHT) benzoate, 3) estradiol (E2) benzoate or 4) safflower oil. Mares were given gonadotropin releasing hormone (GnRH) on Day 3 of estrus (pretreatment) and again 24 h after the last steroid or oil injection. Treatment with testosterone propionate resulted in a greater (P less than 0.05) follicle-stimulating hormone (FSH) response to the second injection of GnRH compared with all other treatments. Treatment with DHT ...
Afonso T, Giguère S, Rapoport G, Barton MH, Coleman AE.Pimobendan is an inodilator used in dogs for the management of heart failure due to myxomatous valve disease or dilated cardiomyopathy. The lack of data regarding the effects of pimobendan in horses prevents the rational use of this drug. Objective: To determine the cardiovascular effects of pimobendan in healthy mature horses. Methods: Randomised experimental study. Methods: Five horses were fasted overnight prior to receiving i.v. pimobendan (0.25 mg/kg bwt), intragastric (i.g.) pimobendan (0.25 mg/kg bwt) or i.g. placebo with a washout period of one week between each administration. Horses ...
Nap RC, Wouda W, Firth EC, Dik K, von Dijk P.The case of a horse affected with frontal sinusitis, in which neurological complications occurred following trepanation, is reported. The previous history of the animal as well as the clinical, radiological and pathological findings are discussed.
Bartmann CP, Stief B, Schoon HA.Transendoscopic thermal preparation techniques like laser- or electrosurgery have proved to be most reliable for minimal invasive intrauterine surgery during operative hysteroscopy in mares. To determine the effect of Nd:YAG laser surgery on the endometrium and the complete uterine wall compared with electrosurgery, standard lesions were obtained by transendoscopic monopolar electrosurgery (loop electrode, cutting blade) and Nd:YAG laser surgery (contact, bare fibre, 25 Watt, exposure time four seconds, non contact, 80 Watt, exposure time four seconds) in five healthy mares on days d 0, 7, 14,...
Harrison S.While the importance of religious and magical healing practices in the Late Middle Ages is well established, the ritual aspects of veterinary medicine have so far not been thoroughly explored. This article addresses this lacuna through analysis of a corpus of charms, prayers, and other rituals that were used to cure a group of devastating contagious diseases that afflicted horses: animals that were often afforded complex, professional medical care in this period. It considers the semantic aspects and common features of this group of disease rituals alongside discussions of contagious illness i...
Sertich PL, Pozor MA, Meyers SA, Brown JS.A 9-year-old Thoroughbred stallion was examined because of breeding dysfunction and possible urethritis. The stallion had good libido and readily obtained an erection, mounted, and intromitted but did not thrust and ejaculate. After mounting the mare, the stallion would squeal and dismount. Endoscopic examination of the urethra and bladder revealed irregular, spiculate yellow crystals (< 1 cm in size) and sabulous deposits; numerous calculi were embedded in the mucosa of the bladder. Because the horse was at the start of a breeding season, the owner would not give permission for general anesth...
Brabon A, Labens R, Ramachandran A, Dart AJ, Dowling BA.Four adult horses with histories of moderate abdominal pain and inappetence were diagnosed with delayed gastric emptying and gastric impaction attributed to pyloroduodenal obstruction (three cases) or duodenitis (one case). A stapled side-to-side gastrojejunostomy was performed on all horses. Two horses returned to work and survived ≥3 years. One horse was euthanased 6 months post-surgery due to recurrent abdominal pain, and one was found dead 5 months postsurgery after an unattended foaling.
Still J.This study reports on clinically significant relief of pain along the gall bladder meridian in 15 sport horses. Both local and distant points were needled in this study. Pain relief was marked not only locally but also in remote areas along the gall bladder meridian. Clinical improvement was observed in all 15 horses within 30 seconds to 2 minutes after the treatment had started. Twelve horses and three horses were rated as "cured" and "improved", respectively, when they were re-examined 1-8 days after the treatment. The relief of somatic pain was often associated with improved riding perfor...
Devine DV, Jann HW, Payton ME.To assess gait abnormalities associated with selective anesthesia of the suprascapular nerve (SSN) achieved by use of perineural catheterization and thereby determine the function of that nerve as it relates to gait in horses. Methods: 3 adult horses with no preexisting clinically apparent lameness at a walk. Methods: Each horse was anesthetized; the right SSN was exposed surgically for placement of a perineural catheter to permit delivery of 1 mL of 2% mepivacaine hydrochloride. Six hours after recovery from anesthesia, each horse was videotaped while walking (50-step data acquisition period)...
Newman MJ, Beegle KH, Antczak DF.Monoclonal antibodies to equine lymphocyte antigens were produced, using normal peripheral blood lymphocytes as the immunogen and standard hybridoma techniques. Antibody producing hybridomas were detected by a solid-phase enzyme-linked immunosorbent assay. Antibodies produced by 6 cloned hybrids were characterized further by microlymphocytotoxicity, indirect immunofluorescence, and agglutination assays on peripheral blood lymphocytes, platelets, and erythrocytes. Reaction patterns on leukocytes indicated that these antibodies may recognize at least 3 different cell-surface antigens: (1) an ant...
Pollock RV.Advances in digital technology have vastly increased the speed and content of information transfer. Equine practitioners of the future should be in contact with their office and other information resources at all times through an array of digital networks. Patients and practitioners alike should benefit from better information access.