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.
Stalheim OH, Gallagher JE, Deyoe BL.The luminal surface topography of bovine, equine, porcine, and caprine uterine tubes was studied by scanning electron microscopy. The main types of epithelial cells were secretory and ciliated. Both types were more active during estrus. Cilia were observed in both the infundibular and the ampular parts of the uterine tube, but ciliated cells were more numerous than secretory cells on the surface of the fimbriae. Sperm were observed in the ampulla of the uterine tube of the cow 2 hours after artificial insemination.
Robinson NE, Dabney JM, Weidner WJ, Jones GA, Scott JB.The digital circulation was isolated in 12 ponies under pentobarbital anesthesia. Blood flow was either controlled by a pump or measured under natural perfusion. The responses to rapid changes and stoppages of blood flow indicated no evidence of autoregulation or reactive hyperemia. Local administration of acetylcholine, histamine, and prostaglandins E1 and E2 decreased prevenous resistance, whereas epinephrine and serotonin caused prevenous constriction. Large doses of epinephrine and serotonin decreased venous caliber. The effects of prostaglandins A1 and F2alpha were variable. The equine di...
Hall LW, Nigam JM.Central venous pressure measurements were made in 74 horses and ponies free from clinical evidence of cardiopulmonary disease. Using the sternal manubrium as the zero reference point, the mean value obtained was 12 cm H2O (S.D. +/- 6). There was a significant correlation with body weight (r=0.6, p less than 0.001) but there was none with age, sex, breed or type. During halothane anaesthesia, using the same reference point, the mean value was 24.5 cm H2O (S.D. +/- 6) in 28 animals in right lateral recumbency, 29 cm H2O (S.D. +/- 8) in 17 animals in left lateral recumbency and -6 cm H20 (S.D. +/...
Ishitani K, Listowsky I.Horse spleen ferritin was fractionated into its constituent isoferritins by isoelectric focusing. Separated isoferritins were stable and showed no tendency to redistribute when re-examined by analytical gel focusing. All of the isoferritins were immunologically indistinguishable when tested with antibodies raised against unfractionated horse spleen ferritin. The separated isoferritins also had similar conformations as determined by circular dichroism. Iron distribution studies, however, revealed a wide disparity among the isoferritins. The most acidic components had the lowest iron content but...
Stickle RL, Erb RE, Fessler JF, Runnels LJ.Unilateral ovariectomy was performed on 3 mares affected with granulosa cell tumors. Tumor fluid in each mare was found to contain estrogen, testosterone, and progesterone. In 2 mares, preoperative blood plasma concentrations of these hormones were comparable to those of a series of clinically normal mares. The other mare, which had a history of aggressive, masculine behavior, had higher testosterone content in the tumor fluid and in the preoperative blood sample. After surgical removal of the tumors, each mare developed follicles and ovulated with the remaining ovary. Each was eventually bred...
Lokhorst HM, Breukink HJ.Two cases of Auto-immune hemolytic anemia (AHA) in the horse are described. The pathogenesis of AHA in man is related to the findings in the horses. Besides from routine hematological and biochemical investigations specific data were obtained from the erythrocyte osmotic fragility test, the Coombs test, the serum haptoglobulin level and the cold agglutinin test. The first patient, a six month old Dutch standardbred colt, probably suffered from an acute attack of cold-induced hemoglobinuria with severe anemia and acronecrosis of the tops of both ears and of several parts of the skin that had be...
Lumsden HJ, Valli VE, McSherry BJ, Robinson GA, Claxton MJ.The hematological response to acetylphenylhydrazine hemolytic anemia was studied in three standardbred horses. The lifespan of erythrocytes produced during the most severe phase of the anemia were measured with 75-selenomethionine and found to be 144 days as compared to the 139 day lifespan in response to hemorrhagic anemia or 155 days in normal standardbred horses measured previously using the same technique. The erythrocyte counts returned to initial values in 42 days (37, 34 and 54 days) a mean erythrocyte production of 6.4 times 10-12 erythrocytes/day. The mean hemoglobin production was 0....
Hatziolos BC, Sass B, Albert TF, Stevenson MC.Recurrent epistaxis and locomotor and visual disturbances leading to blindness in a 7-year-old gelding appeared to have resulted from a spreading fungal granuloma of the guttural pouch. The inflammatory area extended to the intracranial segment of the right optic nerve and to the region adjacent to the optic chiasma. Microscopically, changes indicative of multiple foci of ischemic infarction were noticed in the retina, optic nerves, optic chiasma, and optic lobe. The profusely growing fungal elements in the guttural granuloma had the morphologic characteristics of an Aspergillus sp.
Lumsden JH, Valli VE, McSherry BJ, Robinson GA, Claxton MJ.Hemorrhagic anemia was experimentally produced in three Standardbred horses by removing approximately 63% of the red cell mass and the accompanying plasma during a three day interval. Red cell parameters were examined daily for 45 days and then weekly until termination of the experiment 250 days after production of the anemia. Leukocytes, platelets and bone marrow aspirates were examined at regular intervals for 25 days after the final phlebotomy. At 24 hours after the last bleeding, 75-selenomethionine was injected intravenously to measure the lifespan of the newly produced erythrocytes. The ...
Roberts MC, Pinsent PJ.Three horses suffering from malabsorption were shown to have alimentary lymphosarcoma predominantly affecting the small intestine and the associated lymph nodes. The diffuse cellular infiltration in two of the case produced marked changes in the villous architecture reducing the available mucosal surface area, and, with lowered or barely detectable disaccharidase activities, contributed to the impairment of digestive-absorptive processes. One of the horses maintained a voracious appetite and was not diarrhoeic, but failed to gain weight, indicating differences in the production and utilisation...
Gelatt KN.Traumatic iridocyclitis and hyphema in the horse usually follow blunt blows to the orbit and eye. The condition is characterized by miosis, ocular hypotony, ciliary flush, swelling of the iris, and hemorrhage with excessive fibrin in the anterior chamber which permits from 2 to 6 weeks. Vigorous treatment with mydriatics, topical and systemic corticosteroids is recommended. Possible complications include anterior and posterior synechiae, cataracts, and fibropupillary membranes.
Jeffcott LB, Hickman J.This paper describes the surgical treatment of 14 horses exhibiting chronic back pain attributed to impaction and overriding of the dorsal spines in the thoracolumbar region. The technique involved the resection of the summits of one or more dorsal spines following midline division of the supraspinous ligament. All the horses returned to full work after a convalescent period of at least four months, and 12 of them showed considerable improvement in their form and performance. A post-surgical complication encountered in one case was the development of new bone on the edge of a resected spine. T...
Scott EA, Kneller SK, Witherspoon DM.The physiologic closure of the ductus areteriosus was determined in 4 foals less than 16 hours old. The common carotid artery was catheterized, using local anesthesia and tranquilization, and contrast medium was injected into the ascending aorta. Radiographs were made of heart and great vessels during and after the injection to visualize the pathway of injected contrast medium.
Grigor'eva IA, Sergeevich EA, Lyskovtsev MM, Oleneva AG, Pushkarev VV.Dry erythrocytic diagnostic agents were obtained under experimental conditions for determination of antiglobulins forming in the organism of man and animals under the effect of serum preparations from the blood of horses and homologoum immunoglobulins. A study was made of the sera of 100 patients with tick-borne encephalitis treated with heterologous and homologous immunoglobulins of directed action; in response to the administration of horse gamma-globulin antiglobulins (in titres below 1 : 10000) appeared in the serum; they circulated in the blood for long periods and inhibited the accumulat...
Bowen JM, McMullan WC.The neurally evoked contractile response of the upper lip muscles of horses anesthetized with halothane was used to evaluate the neuromuscular blocking property of oxytetracycline which was administered intravenously at total dose rate of 21 to 28 mg/kg. This dose rate did not alter the contractile response which had a mean control value (and standard error; SE) of 1.76 plus or minus 0.22 kg. Arterial blood pressure was not affected by these dose rates. Neuromuscular blocking effect of the antibiotic occurred when it was administered during partial neuromuscular blockade which had been induced...
Anderson MG.A group of clinically normal horses was subjected to controlled strenuous exercise. Elevated serum concentrations of lactic dehydrogenase, aldolase and creatine kinase were observed after exercise but no significant change in serum glutamic-oxalacetic transaminase was noted. These changes were reduced by repeated exposure to exercise suggesting that measurement of serum enzyme elevations, particularly creatine kinase, might be a useful index of fitness in the horse. Administration of prednisolone prior to exercise also reduced these changes. Since the serum enzyme concentrations had returned t...
Dawson FL, Durrant DS.Seventy-three samples of serum, from 69 horses and one zebra, were subjected to the Rose Bengal Plate, serum tube agglutination, complement fixation, and anti-equine globulin (Coombs') tests for brucellosis. Fifty-one of the samples, from 48 horses, were submitted by practising veterinary surgeons; of these, 22 samples were associated with clinical conditions which might have been due to brucellosis. Fourteen samples were from healthy horses known to have been in contact with infected cattle, and six were from horses which were known not to have been exposed to brucellosis. More reactions at a...
Goulden BE, Barnes GR, Quinlan TJ.This research presents a unique case of laryngospasm in a horse, a condition that is often observed in cats and other domestic animals, but rarely reported in horses. Traditional methodologies […]
Bove AA.Myocardial blood flow is the major determinant of oxygen delivery to the myocardium, since oxygen extraction by the myocardium is near maximum in the resting state. Regulation of flow during exercise depends on local metabolic factors and, to a small extent, on autonomic tone. Maximum flow of 5-6 times resting has been measured in reactive hyperemia experiments. In strenuous exercise, myocardial oxygen delivery appears to be adequate and flow reserve seems capable of handling the increased oxygen demand. No evidence of myocardial failure in normal hearts due to excess exercise has been present...
BonenClark GD, MacKay RJ, Ward RE, Sheerin B.To evaluate the humoral response of horses to vaccination, using a murine monoclonal anti-idiotypic antibody (A4) that shares an epitope with lipid A. Methods: Serum concentrations of antilipid A antibody and 1C9 (epitope on murine monoclonal antilipid A antibody) were measured serially during the period of vaccination with A4. Methods: 6 clinically normal adult ponies. Methods: Ponies were inoculated IM 3 times at monthly intervals with A4. Two weeks after each inoculation, serum was obtained and was assayed by ELISA for antilipid A and 1C9 concentrations. Additional vaccinations were given t...
Ramzan PH.Fractures involving the fetlock region are encountered commonly in Thoroughbred racehorses. Condylar fractures of the distal metacarpus/metatarsus and mid-sagittal fractures of the proximal phalanx account for the majority of fetlock injuries during both racing and training and clinical features, management and outcome of these injuries have been well described. Transverse fractures of the distal diaphysis of the third metacarpus, however, are seldom observed and have received little attention in the literature. This paper describes clinical and radiological findings associated with 6 cases en...
Proudman CJ, Knottenbelt DC, May SA, Edwards GB.Several imaging techniques were used to diagnose hypoplasia of the soft palate in a horse. The absence of the caudal soft palate, hypertrophied lymphoid tissue and the formation of a pseudouvula were observed endoscopically. Plain and contrast radiography were used to demonstrate a soft palate remnant and to identify structures rostral to the epiglottis. Retrograde endoscopy of the pharynx via a tracheotomy incision is described.
Merkt H.The use and techniques of artificial insemination for horses in Germany over the last 30 years is described. Artificial insemination appears to produce pregnancy percentages equal to those from normal breeding methods and its continued availability under veterinary supervision is recommended in conditions where disease, disability or distance debar normal service.
de Brot S, Junge H, Hilbe M.Two horses were presented with non-specific clinical signs of several weeks' duration and were humanely destroyed due to a poor prognosis. At necropsy examination, both horses had multiple small, white nodules replacing pancreatic tissue and involving the serosal surface of the abdominal cavity, the liver and the lung. Microscopically, neoplastic cells were organized in acini and contained abundant (case 1) or sparse (horse 2) intracytoplasmic zymogen granules. Immunohistochemically, both tumours expressed amylase and pan-cytokeratin, but not insulin or neuron-specific enolase. In case 2, a lo...
Allen WE.Seven Welsh pony mares (9 pregnancies) received either 50 mg, 100 mg or 150 mg progesterone on alternate days, starting on day 21 of gestation. All but 2 pregnancies failed following prostaglandin administration on day 27. Although both mares were receiving the 150 mg progesterone dose rate, this treatment was not consistently successful in preventing pregnancy failure after prostaglandin administration.
Reed SA, Streff LN.The field of equine sports medicine and rehabilitation provides a career opportunity for students interested in remaining in the horse industry but not focused on a career as a veterinarian. However, throughout the United States, there are limited educational opportunities for undergraduate students to prepare for this career. The objective of this work was to determine what skills and theoretical knowledge professionals in the equine rehabilitation industry deemed most useful for employment in the equine rehabilitation industry, and, using that information, develop a curriculum to meet these ...
Pintea V, Ganţă C.The mm. lumbricales and the mm. capsulares of the shoulder and hip joints of the horse are rich in neuromuscular spindles (NMS). The mm. interossei of the pig, but not of the horse, have NMS too. In the m. orbicularis of the eye, m.hyo-epiglotticus and the m. palatinus of the horse NMS are absent. In the vestigial muscles, as m. extensor digitorum brevis and m. of Thiernesse, NMS are absent too. A role of modulator for the proximal muscles of the limbs by the distal muscles is hypothesized, as well as the absence of NMS in striated muscles not involved in locomotion.
Baltsen M, Bøgh IB, Byskov AG.Meiosis activating sterols (MAS) are pre-cholesterol sterols that can be isolated from follicular fluid (FF-MAS) or testes (T-MAS). Meiosis activating sterols trigger the resumption of meiosis in cultured meiotically competent oocytes. In the present work MAS, cholesterol and progesterone were assayed by HPLC in follicular fluids collected from pony mares at fixed days after the last ovulation. Follicles were divided into two groups according to whether they were aspirated before or after Day 17 after the last ovulation. The latter group was further divided according to whether the follicle di...
Gandini M, Giusto G.In jejunocaecal anastomosis leaving a necrotic ileal stump has been implicated in complications and poor outcomes. Elective inversion of the necrotic stump using a nasogastric tube has been previously described, although this procedure can be cumbersome and can cause caecocolic orifice occlusion. Objective: To describe the use of a new device for elective inversion of necrotic ileal stumps. Methods: Case report. Methods: Details of the four horses that underwent intestinal resection and anastomosis with elective inversion of the ileal stump were retrieved from their medical records. For each c...
Martin KH, Redding LE, Boyle AG.Although equine strangles is reportable in all states, synchronous reporting of this disease does not occur across the country. States have variable regulations on reporting (actionable, notifiable, and monitored) and no mandatory comprehensive databases exist for tracking prevalence. In this study, which is a companion to our recent publication on veterinarians' opinions on this topic, we solicited equine affiliates' (including horse owners, horse business owners/trainers, breeders, and barn managers) opinions on reporting of strangles and factors influencing their opinion. A total of 518 equ...
McCue PM, Troedsson MH, Liu IK, Stabenfeldt GH, Hughes JP, Lasley BL.Thirty-seven seasonally anoestrous mares were divided into treatment and control groups and given 10 micrograms of native GnRH (GnRH) per hour using a peristaltic pump, or 10 micrograms GnRH agonist (GnRHa) twice daily, beginning on either 13 January, 13 February or 14 March. Treatment with GnRH was equally effective in inducing ovulation in January (4/5), February (4/5) and March (3/4). GnRHa treatment was more effective in inducing ovulation in February (4/5) and March (4/4) than in January (2/8). Peak luteinizing hormone (LH) concentrations in mares induced to ovulate with GnRH (7.4 +/- 1.5...
DeVico AL, Issel CJ, Le Grice SF, Payne SL, Montelaro RC, Sarngadharan MG.The immunogenicity of the equine infectious anemia virus (EIAV) reverse transcriptase (RT) was examined by immunoblot assay with recombinant EIAV RT. All of the 19 sera from EIAV-infected horses tested contained antibodies that recognized EIAV RT and directly inhibited the polymerase activity of the enzyme. An examination of sera obtained sequentially from two experimentally infected animals revealed that anti-RT antibodies arise early in infection and increase in level. The appearance of the antibodies correlated with progression toward the asymptomatic period of infection.
Martens JG, Stephens KA, Kerchner LJ, Heck FC, Martens RJ.Plasma fibronectin concentrations were measured in clinically healthy mares and their neonatal foals, using a modified human fibronectin competitive enzyme-linked immunosorbent assay. Ranges of plasma fibronectin were established in clinically healthy horses, and the assay was reliable and reproducible. Plasma fibronectin concentrations were similar in mares and foals, both before and after colostrum ingestion.
Oladunni FS, Reedy S, Balasuriya UBR, Horohov DW, Chambers TM.Equine herpesvirus type 4 (EHV-4) is mildly pathogenic but is a common cause of respiratory disease in horses worldwide. We previously demonstrated that unlike EHV-1, EHV-4 is not a potent inducer of type-I IFN and does not suppress that IFN response, especially during late infection, when compared to EHV-1 infection in equine endothelial cells (EECs). Here, we investigated the impact of EHV-4 infection in EECs on type-I IFN signaling molecules at 3, 6, and 12 hpi. Findings from our study revealed that EHV-4 did not induce nor suppress TLR3 and TLR4 expression in EECs at all the studied time...