"Horses" is a broad topic that encompasses various aspects of equine biology, behavior, and management. This category includes studies on the anatomy, physiology, and genetics of horses, as well as their behavior, nutrition, and care. Research in this area may also cover the historical and cultural significance of horses, their roles in agriculture, sport, and therapy, and the challenges associated with their conservation and welfare. The page aggregates peer-reviewed research articles and scholarly studies that explore the multifaceted relationships between humans and horses, examining both scientific and socio-economic perspectives.
Reynolds BL, Stedham MA, Lawrence JM, Heltsley JR.A space-occupying intracranial mass was diagnosed in a horse. The clinical findings included blindness, circling to the right, apprehension, anorexia, weight loss, and leaning against the stall. On ophthalmoscopic examination, the most striking observation was complete bilateral devascularization of the retinas. The horse was euthanatized and necropsied. Necroscopy revealed the mass to occupy the olfactory and frontal areas of the left hemisphere of the brain and part of the left frontal sinus. Microscopically, the mass was an adenocarcinoma and probably arose from the lining epithelium of the...
Llewellyn HR.A tentative diagnosis of a fistula between the tendon sheaths of the right extensor carpi radialis and the intercarpal joint was confirmed by positive contrast radiography following injection of sodium diatrizoate into the joint. Surgical removal of a tag of synovial membrane and repair of the fistula was carried out. Post surgical treatment included mild exercise to prevent adhesions within the sheath. A month following discharge, contrast radiography revealed no communication between joint and tendon sheath. At this time mild distension of the sheath was relieved by aspiration and it did not...
Blue MG.In a retrospective study of selected cases, abdominal colic in 30 horses was attributed to enterolith obstructions of the large intestine. Obstructions caused by "true" enteroliths were confined to horses more than four years old. Prominent clinical features were recurrent mild abdominal pain, inappetance, gaseous distension and minimal intestinal motility. The various aspects of the clinical syndrome, including diagnostic problems and clinical management, are discussed. Most obstructing enteroliths were found near the beginning of the small colon and most horses contained only a single major ...
Franks PW.A technique was developed using radioactive isotopes as a source of radiation for the treatment of injuries to the superficial and deep flexor tendons and the associated ligaments in the horse. The treatment area was sub-divided so that different dosages could be applied over the limb as necessary. A plaster of Paris impression was taken of the whole area to be treated. In the isotope laboratory a plaster negative was made and loaded with the dose of radioactive isotope. The loaded cast was then strapped to the horse's limb for the calculated time, usually about three days. A total of 42 horse...
Ray AC, Tamulinas SH, Reagor JC.Experimental animals (rabbit, rat, goat, sheep, and pony) were given cantharidin or dried preparations of blister beetles (Epicauta lemniscata) to stimulate naturally occurring toxicosis in which beetles were ingested with alfalfa hay. A sensitive high-pressure liquid chromatographic method, involving derivatization of cantharidin with p-nitrobenzyloxyamine, was developed to detect the toxin extracts of ingesta, fluids, and tissues from these severely poisoned animals. Urine and ingesta from the upper portion of the gastrointestinal tract, containing from 1 to 20 ppm of cantharidin, were the m...
Cox JE, Edwards GB, Neal PA.The authors analyse data collected over 23 years from 500 cryptorchid horses. They show that left- and right-sided abdominal cases occur with approximately equal frequency in ponies. Approximately half the right-sided unilateral abdominal cases have the epididymal tail descended while only 20 per cent of the left-sided cases do. These findings are briefly discussed. From their analysis of inguinal cryptorchidism the authors conclude that it is a relatively more complex phenomenon with incidence changing with age as well as breed. Right-sided retention predominates in young ponies, probably bei...
Sharp DC, Garcia MC, Ginther OJ.Luteinizing hormone (LH) was quantified in pony mares during artificially induced sexual maturation. Ovarian follicular development was also assessed by rectal palpation of the ovaries. With the exception of large periovulatory LH concentrations in two mares that ovulated, LH concentrations were not significantly different in mares undergoing sexual maturation and thus having marked follicular development when compared with mares that were not undergoing sexual maturation and thus did not have marked follicular development. These results indicate a dissociation in time between the onset of fol...
Hall LW.Catheters were implanted through the left atrium into large veins drawing blood from regions of the diaphragmatic lobes in five ponies. Measurement of oxygen and carbon dioxide tensions in blood samples drawn through these catheters showed that in laterally recumbent conscious and anaesthetised animals the function of the lowermost lung is progressively impaired while in the supine position the function of both lungs is adversely affected.
Amerault TE, Frerichs WM, Stiller D.An agglutinating antigen and a rapid card test (CT) for equine piroplasmosis was developed. The antigen for the CT was prepared from lyophilized Babesia caballi complement-fixation (CF) antigen. Serum and plasma samples for testing were obtained from known B caballi-infected horses and clinically normal horses maintained at the laboratory. Serum samples also were obtained from horses outside the continental United States, in areas where piroplasmosis is endemic. Comparative CT and CF tests were done on all samples. The CT correctly identified 85% of 192 plasma samples from known infected and n...
MacKay RJ, Urquhart KA.Eight mature horses which had been affected with a moist cough for six weeks were found to have large numbers of eosinophils in tracheal mucus samples taken by transtracheal washing. These horses were kept on irrigated pasture and fed a hay-free diet. A companion yearling donkey was found to be passing Dictyocaulus arnfieldi larvae in its faeces. Two oral treatments with a dose of thiabendazole (440 mg/kg) resulted in the resolution of the clinical signs and the disappearance of eosinophils from transtracheal washings. The eosinophilic bronchitis seen in these horses was presumed to be a manif...
Roberts MC.Two young ponies had the prescrotal portion of their penises accidentally amputated during castration. They both developed ascending urinary tract infections over the next 4 weeks. One pony had a necrotising cystitis and pyelonephritis, the other improved markedly after a urethrostomy had been performed but was destroyed several months later.
Drudge JH, Lyons ET, Tolliver SC.Critical tests were conducted on eight horses naturally infected with several species of large and small strongyles from population B. Tested were six benzimidazoles, including thiabendazole (2 lots) (44 mg/kg of body weight); mebendazole (8.8 mg/kg); cambendazole (two formulations) (20 mg/kg); fenbendazole (10 mg/kg); oxibendazole (10 mg/kg); and oxfendazole (10 mg/kg). All compounds were administered by stomach tube except one of the two cambendazole formulations which was an intraoral paste. Removal of large strongyles (when present), Strongylus vulgaris and Strongylus edentatus, was 100% b...
Taylor CE, Rosenthal RO, Taylor-Robinson D.The presence of allugtinins to the causative organism of contagious equine metritis (C.E.M.) in human serum has been confirmed. Agglutinins were found in the serum of 84 (37.6%) of 223 patients with non-gonococcal urethritis (N.G.U.), and in 12.5% of these patients there was a four-fold or greater rise in titre during the course of their illness. There was no evidence that these agglutinins were the result of infection by chlamydiae or ureaplasmas. Certain patients with these agglutinins seemed to respond better to therapy with antibiotics to which the C.E.M. bacterium is susceptible in vitro ...
Fernie DS, Cayzer I, Chalmers SR.A passive haemagglutination test (PHT) which has been developed for the detection of antibodies to the contagious equine metritis organism (CEMO) in serum is described. Samples from each of 30 mares with metritis were positive with titres in the range 256 to 4096. Samples from each of 239 clinically normal mares and 30 colts and fillies believed not to have been exposed to CEMO were negative with titres of less than 256, the majority of samples (97 per cent) showing a titre of 32 or less.
Norton AM, McGilp D, Vasey JR.A 4-month old, 200 kg, grey warmblood colt presented for a firm, non painful mass on the distal medial aspect of the left third metatarsus. Excisional biopsy revealed a diagnosis of haemangiosarcoma. Equine haemangiosarcoma is uncommon and only limited reports of successful treatment are available. The prognosis for survival is therefore considered to be poor. After two separate incidences of recurrence with incomplete excision of the tumour, intralesional treatment with cisplatin without excision or debulking was performed on three separate occasions. Intralesional cisplatin injection was p...
Loinaz RJ, Boutros CP, Rakestraw PC, Taylor TS.To report a laryngotomy approach for the removal of the nasal septum in adult horses. Methods: Descriptive study. Methods: Horses (n = 10). Methods: Near-total resection of the nasal septum was made using a modification of a previously reported 3-wire technique using a trephination approach and a 2-wire technique using a laryngotomy approach. Surgical time, ease of technique, complications, and outcome were recorded. At 45 days, horses were euthanatized and septal measurements made. Results: Near-total resection of the nasal septum was accomplished with both techniques without complications. I...
Loftin MK, Levine JF, McGinn T, Coggins L.State veterinarians in 11 southeastern states completed a questionnaire designed to determine the proportion of equids in the region that were seropositive for equine infectious anemia (EIA). Cases of EIA were diagnosed in each of the states surveyed. Distinct geographic clusters of cases were apparent in Tennessee and Kentucky adjacent to the Mississippi River, in the Piedmont of North Carolina at the Virginia border, in north central Georgia, and throughout the Florida peninsula. It is suggested that the national EIA program could be improved by standardization and wider application of unifo...
Kakoi H, Kikuchi M, Ishige T, Hirosawa Y, Tanaka S, Nagata SI.To confirm the positive conversion of antibodies against erythrocyte antigens in horses, possible blood transfusion donor horses selected from draft horse populations were periodically monitored with an indirect antiglobulin (Coombs) test for approximately 3 years. In this study, 19 horses (16 females and 3 males) were investigated, and five mares showed alloantibodies during the monitoring period. Four mares were typically pregnant when positive conversion was detected, whereas no particular cause of conversion could be observed for one mare based on its clinical records. In the analyzed hors...
Schaefer RJ, Cullen J, Manfredi J, McCue M.A gene's response to an environment is tightly bound to the underlying genetic variation present in an individual's genome and varies greatly depending on the tissue it is being expressed in. Gene co-expression networks provide a mechanism to understand and interpret the collective transcriptional responses of genes. Here, we use the Camoco co-expression network framework to characterize the transcriptional landscape of adipose and gluteal muscle tissue in 83 domestic horses (Equus caballus) representing 5 different breeds. In each tissue, gene expression profiles, capturing transcriptional re...
Muñiz Fontán M, Moure González JD, Mirás Veiga A, Rodríguez Núñez A.Children's equestrian activities in the domestic, play activities, sports and educational areas are relatively frequent, and are not exempt from risks. Nevertheless, there is a lack of data on horse-related injuries, their circumstances and the key points for their prevention. Methods: Retrospective and descriptive study of pediatric equestrian injuries admitted to Hospital between July 1997 and September 2008. Results: A total of 17 patients with ages between 4 and 17 years were analyzed. There were 14 accidental falls, 2 kicks and 1 bite, and 8 patients had lost consciousness after the accid...
Lumsden JM, Caron JP, Stickle RL.Bilateral radiographically persistent proximal third metatarsal physes and concurrent cuboidal bone immaturity were identified in a foal. Repair of a Salter type-II fracture of the left proximal third metatarsal physis was accomplished by use of lag screw fixation. A 6-day-old Arabian foal, intended for use as a show horse, was referred because of severe unilateral hind limb lameness and valgus deformity. A Salter type-II fracture of the proximal portion of the third metacarpal bone was identified radiographically and repaired by use of cancellous lag screws. The fractured limb was further sup...
Young KM, Lunn DP.Technologic advances in immunodiagnostic testing have enhanced our understanding of the pathogenesis of a broad array of diseases, including infectious diseases, immunodeficiency disorders, and immune-mediated disorders. If applied rationally, with an understanding of the questions the tests answer as well as the limitations that constrain their use, these tests can serve as valuable aids in the diagnosis and management of equine diseases.
Rodger FE, Illingworth PJ, Watson ED.Although the mare corpus luteum (CL) is capable of aromatization, the expression of other enzymes involved in estradiol synthesis is not yet clear. This study examined the localization of P450C17 in the mare CL at different stages of its functional development. In ovaries from follicular phase mares P450C17 was localized in the theca cells of ovarian follicles. Following ovulation, no immunostaining for P450C17 was detected in the mature CLs of nonpregnant mares. In pregnant mares, no immunostaining for P450C17 was identified in the corpus luteum prior to secretion of eCG by the feto placental...
Buzzetti AP, Nothaft IT, Paganela JC, Franzan BC, Braga GI, Barreira APB, de Lima LR, de Almeida FQ.This study aimed to perform ultrasonographic evaluation of the digital flexor tendons of jumping horses undergoing complementary training on a treadmill. Fifteen Brazilian Sport horses were divided into two groups: Group I with 7 animals in physical training complementary to the standard training at the Brazilian Army's Riding School; and Group II with 8 animals in standard training used in the Brazilian Army's Riding School. Complementary training was performed on a treadmill on an inclined plane. Ultrasonographic images were taken at the beginning and at the end of training. The left thoraci...
Zetterström SM, Boone LH, Weatherall KM, Caldwell FJ.To describe a minimally invasive technique for semitendinosus tenotomy with ultrasonographic guidance and to evaluate procedural complications. Methods: Experimental study. Methods: Cadaveric equine hind limbs (n = 16). Methods: A stab incision was performed distocaudal to the tibial insertion of the semitendinosus muscle with ultrasonographic assistance. After transection of the tendon with an arthroscopic retrograde knife, the tendon edges palpably retracted, and complete transection was confirmed by ultrasound. Limbs were dissected to confirm the degree of tendon transection and to identify...
Freeman DE, Richardson DW, Tulleners EP, Orsini JA, Donawick WJ, Madison JB, Ross MW, Beroza GA.Loop colostomy was performed in 10 horses as treatment for grade-III rectal tears (n = 6 horses), small-colon infarction (n = 2 horses), perirectal abscess and stenosis (n = 1 horse), and small-colon stricture (n = 1 horse). In 7 horses, the colostomy was constructed through a single incision low in the left flank, with closure of the incision around the stoma (single-incision technique). In 3 horses, 2 of which had colostomy performed as a standing procedure, the selected segment of small colon was placed from a flank incision into a separate, small incision low in the left flank (double-inci...
Marland A, Sarkar P, Leavitt R.Tenoxicam (Mobiflex) was administered orally to four standardbred mares at a dose of 200 mg. Elimination profiles of tenoxicam and hydroxytenoxicam were generated based on quantitation of these analytes in urine and serum by liquid chromatography (LC) with ultraviolet detection. Tenoxicam was confirmed by LC-tandem mass spectrometry daughter ion mass spectra in the last postadministration sample in which tenoxicam was detected. The tenoxicam and hydroxytenoxicam urinary elimination profiles had the same shape for the same horse; however, each horse was significantly different from the others. ...
Markel MD, Meagher DM, Ford TS.A 3-month-old Quarter Horse filly stepped on a fence staple and developed navicular bone osteomyelitis of the right hindfoot. A 1.5-cm spherical portion of medullary cavity containing purulent material was debrided and flushed with 0.9% NaCl solution. Cancellous bone was collected from a caudal sternebra and placed into the defect. The solar defect had filled with granulation tissue and was epithelialized 6 weeks after surgery. At 6-month follow-up evaluation, the navicular bone defect had healed and the foal was sound on the limb. Cancellous bone grafting may have merit for the treatment of n...
Anderson GF, Landsheft B.Performance horses should be thoroughly examined before sale to detect any defects that could render them unsuitable for the purchaser's intended use. With the horse in its stall, the eyes, nasolacrimal puncta, external ear canals and mouth are examined, the rectal temperature measured and the heart, lungs, trachea and sinuses auscultated. Moving the horse out of the stall, the head, parotid glands, mandibular lymph nodes, larynx, neck muscles, jugular veins and cervical vertebrae are inspected. The scapula, point of the shoulder, withers, tuber sacrale and point of the hip are palpated, after...
Browne NS, Scarratt WK, Robertson J.A 10-year-old Andalusian mare was presented for evaluation of weight loss, increasing periods of recumbency, and swelling of the lower limbs. Radiographs revealed severe palisading to solid periosteal new bone formation in numerous locations. Necropsy revealed a metastatic malignant adenocarcinoma of ovarian origin with secondary hypertrophic osteopathy. Une jument d’Andalousie âgée de 10 ans a été présentée pour évaluation à la suite d’une perte de poids, de périodes croissantes de décubitus et d’enflure dans les membres inférieurs. Les radiographies ont révélé des lésio...
Harmegnies NF, Duvivier DH, Vandenput SN, Art T, Lekeux PM, Votion DM.This study aimed to compare exercise-induced pulmonary perfusion redistribution in healthy vs. 'heavey' horses using scintigraphy, a minimally invasive technique. Six healthy (A) and 5 'heavey' horses in remission (B(I)) and during clinical signs of disease (B(II)) were investigated. Dimensions of the exercising pulmonary perfusion (QE) images were expressed in percent of the resting perfusion (QR) images. Computed QE to QR ratios (QE/QR) images enabled the definition of the region more perfused at exercise than at rest (R1). In all groups, exercise induced a major enlargement of the Q image b...
Koljonen V, Söderlund T, Mäkisalo H, Gissler M.Contacts between humans and animals inevitably involve encounters possibly resulting in the human being injured. During the period of 2000 to 2014 almost 90 people died in this kind of conflict in Finland. Of these deaths, one third were associated with horses. In addition, over the same period 85 people died in traffic accidents in which an animal was hit by a car. Accidents requiring hospitalization occurred for approx. 8 000 people.
Wrangberg T, Kendall A. Proper identification of healthy subjects is essential in case-control studies. However, standardized definitions of healthy controls are lacking in equine orthopaedic research. Objective: The aim of this study was to define the non-invasive methods used for selecting healthy control horses in osteoarthritis (OA), desmitis and tendinitis research. Methods: Systematic review. Case-control studies with a healthy control group and longitudinal studies where horses had to be healthy at the start were included. Studies where joints were visualized by arthroscopy or post-mortem examination ...
