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.
Science (New York, N.Y.)September 14, 1984
Volume 225, Issue 4667 1172-1174 doi: 10.1126/science.6089344
Lagerweij E, Nelis PC, Wiegant VM, van Ree JM.The twitch procedure in horses attenuates the increase in the heart rate evoked by pain-inducing stimuli and the reaction of the animals to such stimuli. Endorphin systems are probably involved in the effectiveness of the twitch, since its action is blocked by naloxone and its application increases plasma concentrations of immunoreactive beta-endorphin. The mode of action of the twitch cannot be explained by the generally accepted theory of divertive pain and may resemble that of classical acupuncture.
Chang HC, Takashima I, Arikawa J, Hashimoto N.A biotin-labeled antigen (BLA) was adapted to a sandwich enzyme-linked immunosorbent assay (S-ELISA) for detection of Japanese encephalitis (JE) antibody in a variety of animal sera. JE antigen was fixed on the wells of a microplate and became bound to the specific antibody which could react with a peroxidase-labeled avidin conjugate and azino-di-(3-ethylbenzthiazolin sulfonic acid) (ABTS) as a substrate. The BLA-S-ELISA could simultaneously detect JE antibody in all hemagglutination inhibition (HI) positive sera from man, swine, monkey, horse, cattle, rabbit, rat, mouse and pigeon by using th...
Didkowski S, Kaminski M, Kerjan P, Tomaszewska-Guszkiewicz K, Zurkowski M.By the method of precipitation with Rivanol (2-ethoxy-6,9-diaminoacridine lactate) and ammonium sulphate followed by chromatography on DEAE cellulose three genetic variants of transferrin were purified from equine serum: D, M and R. Their molecular mass determined in this study was 80 000, and it was identical for all three variants, which differed slightly in their amino acid composition. The protein level was determined in the serum of 535 two-year-old thoroughbred English horses by the method of rocket immunoelectrophoresis using antibodies obtained against three transferrins. The individua...
Bertone AL, Aanes WA.Three cases of unilateral congenital phalangeal hypoplasia are described in 2 horses and 1 mule. Radiographic lesions include severe hypoplasia of the 3rd phalanx, and associated hypoplasia of the 2nd phalanx in 2 cases, and hypoplasia or aplasia of the navicular bone in 2 cases. All animals could ambulate but were lame. Two cases had palpable laxity at the level of the coronary band. Documented etiology was not determined for the dysgenesis, but possibilities include inherited transmission or an environmental teratogen.
Hildreth SW, Beaty BJ, Maxfield HK, Gilfillan RF, Rosenau BJ.Enzyme immunoassays (EIAs) for eastern equine encephalomyelitis (EEE) and Highlands J (HJ) virus antigens were compared in a retrospective study with standard virus isolation procedures (VIP) for detection of alpha virus-infected mosquito pools. The original VIP was a plaque assay in chick embryo cell culture, and was performed in the years from 1979 to 1981. Using the original VIP as the reference standard, the sensitivity rate of the EIA was 0.7674 and the false negative rate was 0.2326. However, when the storage age and the initial virus titer of the sample were considered, the sensitivity ...
Trim CM.Complications following the use of the cuffless large animal endotracheal tube during general anesthesia in 2 horses are reported. One horse developed laryngeal edema during recovery. The edema was treated successfully with dexamethasone, but severe laryngeal trauma was confirmed 24 hours later at necropsy. The second horse had a swollen tongue and had difficulty eating for 3 days after anesthesia. The condition resolved without treatment. this report is a reminder of the potential damage which can occur from endotracheal intubation.
The Journal of hereditySeptember 1, 1984
Volume 75, Issue 5 413-414 doi: 10.1093/oxfordjournals.jhered.a109968
Sponenberg DP, Harper HT, Harper AL.A bay roan Brabant Belgian stallion (ERn/ ern) was bred to eight chestnut American Belgian mares (ern/ ern), producing 57 foals. Thirty foals were bay roan, 25 were chestnut, one was bay, and one was chestnut roan. The recombination rate was 0.035 +/- 0.024, indicating fairly close linkage between the roan (Rn) and extension (E) loci.
Musselman EE, LoGuidice RJ.A necropsy diagnosis of hypoplastic left ventricular syndrome was made in a day-old foal. The cardiac abnormalities included mitral and aortic valve atresia, patent ductus arteriosus, and a secundum atrial septal defect. The left ventricle was hypoplastic and nonfunctional. The brief survival of the foal was a consequence of left-to-right shunting through the atrial septal defect and right-to-left shunting through the patent ductus. The information is presented to demonstrate the existence of the syndrome as a congenital defect in the horse and to clarify the necropsy findings for the practiti...
Ludwig KG, Craig TM, Bowen JM.Six mares were treated on the day of parturition with an intramuscular injection of 0.2 mg kg-1 ivermectin and placed in a pasture free of equine parasites as soon as possible after foaling. The mares and their foals were compared with a similar group of untreated mares and foals on an adjoining pasture. The experimental data was derived from mare and foal fecal egg counts, foal necropsies and pasture larval counts. Ivermectin administered to mares on the day of parturition, when combined with movement to parasite-free pastures, significantly lowered the cyathostome (small strongyle) egg produ...
Pan LG, Forster HV, Bisgard GE, Dorsey SM, Busch MA.We assessed cardiovascular variables and blood O2 contents in order to characterize O2 transport in ponies during treadmill exercise. In normal ponies at 1.8, 3, and 6 mph, respectively, cardiac output (Qc) increased from 12 l/min at rest to maximum levels of 19.7, 28.7, and 39.9 l/min between 30 and 60 s. Qc then decreased to steady-state levels of 18.2, 24.6, and 32.7 l/min by 4 min. Heart rate (HR) showed a similar biphasic response in the 1st min of exercise. Systolic and diastolic arterial blood pressure (BP) decreased at the onset of exercise by 20-25 Torr (P less than 0.05) and then inc...
Vyslouzil L, Seidl K, Svarcová J, Landsmannová V.A case history of mass foal disease which affected ten of the total stock of 50 foals and killed eight is described. The disease was characterized by respiratory disorders and extensive pneumonias with abscess formation, metastatic abscesses in mesenterial lymph nodes and in other organs. As a result of the examination of two dead foals and three nasal smears from diseased animals, gram-positive bacteria were isolated from the lungs, pulmonary and abdominal abscesses and the nasal smears of the affected foals; with their cultivation, morphological and biochemical characteristics these bacteria...
Douglas-Hamilton DH, Osol R, Osol G, Driscoll D, Noble H.A field trial of artificial insemination in horses with transproted, chilled semen was conducted using a specially designed container which permitted a controlled, slow initial rate of cooling (-0.3 degrees C/min) and maintenance of a final temperature of 4 degrees -6 degrees C for more than 36 hrs. Forty-six mares in 23 states were inseminated with semen from three German Warmblood stallions standing at stud in Hamilton, Massachusetts. A third-cycle conception rate of 91% was obtained.
Hatheway CH, Snyder JD, Seals JE, Edell TA, Lewis GE.Serum levels of equine-botulism antitoxin to toxin types A, B, and E were measured in four type-A botulism patients who had received equine-botulism antitoxin. High circulating levels capable of neutralizing in excess of 1 X 10(8), 9 X 10(7), and 6 X 10(6) 50% mouse lethal doses of toxin of types A, B, and E, respectively, were detected. There was little depletion of type-A antitoxin even though two of the patients had circulating type-A toxin before treatment. The half-life for antitoxin persistence for one patient was calculated as being 6.5, 7.6, and 5.3 days for antitoxin types A, B, and E...
Townsend HG, Leach DH.The anatomical features of 21 equine thoracolumbar spines, obtained from horses with clinically normal backs, were examined and the results compared with recent data on the mobility of the joint complexes of the horse's spine. The thoracolumbar spine can be divided into four regions based upon the morphology of the joint complexes: the first thoracic intervertebral joint (T1-2), the cranial and mid thoracic region (T2-T16), the caudal thoracic and lumbar region (T16-L6) and the lumbosacral joint. The mobility of the intervertebral joints in each of these regions can be related to their morphol...
Soma LR, Korber K, Anderson T, Hopkins J.The effects of furosemide (0.55 mg/kg IV) on the plasma and urinary fentanyl (PFE UFE) concentrations were studied during steady-state conditions. The PFE during the steady-state period was 0.31 +/- 0.027 ng/ml, with no significant changes occurring, even though the rate of excretion of fentanyl (EX) increased during the 1st hour from 112.0 +/- 21.6 to 534.5 +/- 82.9 ng/minute. The EX returned to control levels within 3 hours, as did the UFE. The injection of furosemide increased glomerular filtration rate from 1.97 +/- 0.21 to 3.81 +/- 0.75 ml/kg/min. The fractional reabsorption decreased fro...
Vandeplassche M, Simoens P, Bouters R, De Vos N, Verschooten F.In 214 cases of severe dystocia in mares, of which 141 (66 per cent) were Draught horses, deviation of the head and neck, with or without torticollis, malformed head and limbs were found to be the cause of dystocia. No evidence of a genetic lethal factor was found and torticollis was often combined with scoliosis of the head and, frequently, with malformation of one or more limbs. This is considered evidence of a common aetiology and pathogenesis of the syndrome of malformation. The malformations were found to be associated with an increased incidence of caudal and, particularly, transverse pr...
Held JP, Blackford JT.Three cases of vaginal perforation after coitus are discussed. The most consistent clinical sign is a small amount of blood escaping from the vulvar lips immediately after breeding. Secondary infection and posttraumatic swelling may cause abdominal pain due to rectal impaction. Treatment with high levels of an appropriate antibiotic is important to reduce the risk of a severe infectious peritonitis. The use of artificial insemination or a breeding roll to prevent full intromission is recommended.
Little CB, Kabay MJ.The deep fungal dermatoses that have been reported in Australia have involved Hyphomyces destruens (Hutching and Johnston 1972; Connole 1973; Johnston and Henderson 1974; Miller and Campbell 1982). Entomephthora coronata (Hutching and Johnston 1972; Connole 1973; Miller and Campbell 1982), and Basidobolus haptosporus (Miller and Campbell 1982). These subcutaneous mycoses have occurred on the legs, ventral chest and abdomen (H. destruens), lateral trunk and face (B. haptosporus) and external nares (E. coronata). Metastases to regional lymph nodes are rare (Murray et a1 1979). In a review...
McCoy DJ, Shires PK, Beadle R.Atlantoaxial subluxation secondary to odontoid fracture in a 30-day-old foal was corrected by alignment of the atlantoaxial joint and stabilization with 2 ventrally placed dynamic compression plates. At 90 days after surgery, healing of the fracture, with adequate alignment of the atlantoaxial joint, was confirmed radiographically. The foal was only slightly tetraparetic at that time. At 1 year after surgery, the gait was normal. It was concluded that the technique has advantages over the use of Steinmann's pins or external coaptation for stabilization. The ventral approach allows decompressio...
Forster HV, Pan LG, Bisgard GE, Dorsey SM, Britton MS.We characterized the temporal patterns of pulmonary O2 consumption (VO2) and CO2 excretion (VCO2) in exercising ponies. We also assessed the cardiac, ventilatory, and hematologic contributions to the VO2-VCO2 changes during exercise. At five moderate treadmill work loads in normal ponies, VO2 and VCO2 generally increased progressively throughout the 1st min reaching, respectively, approximately 95 and 80% of steady state by 45-60 s. Between 1 and 1.5 min, Vo2 and Vco2 were either stable or they decreased 300-500 ml, but then each increased slightly, reaching steady-state levels between 3 and 5...
Powers JD, Powers TE, Varma KJ, Gabel AA, Spurlock SL.Quantification of the clinical manifestations of a disease has been a serious problem particularly as related to clinical trials or drug efficacy studies. Historically, this quantification has been limited to categorizing each patient into one of three or four groups, e.g. worse, no improvement, improved. This problem becomes serious when an investigation utilizes an experimentally induced animal disease model. A health index, which quantifies the clinical state of horses which have an experimentally induced beta-hemolytic streptococcal infection, is described. Aspects of experimental design a...
Goetz TE, Coffman JR.Ulcerative colitis, protein losing enteropathy and intestinal histoplasmosis-salmonellosis were diagnosed in a six-year-old Quarterhorse stallion. For six months before examination, the horse experienced a slow continual loss of weight. During the 17 day period of hospitalisation the horse developed progressive generalised oedema. On the 12th day of hospitalisation a severe profuse watery diarrhoea began; the horse was killed five days later.
Thurman JD, Johnson BJ, Lichtenfels JR.Arteriosclerosis caused by Dirofilaria immitis adult parasites was diagnosed in a 20-month-old Quarter horse stallion that died from cantharidin toxicosis. Microscopically, the pulmonary vascular changes were typical of those described as "proliferative endarteritis" in D immitis-infected dogs.
Sonea IM, Bowker RM, Robinson NE.Autoradiography with [125I]-Bolton Hunter substance P ([I]-BHSP) was used to detect substance P binding sites in the equine lung. Specific [I]-BHSP binding sites were very dense over small bronchial vessels, tracheobronchial glands and airway epithelium in large and small airways. The density of [I]-BHSP binding sites over airway smooth muscle was much lower than in the preceding tissues. Competition with an excess of either a specific neurokinin 1 receptor agonist, or a specific neurokinin 2 receptor agonist indicated that most specific [I]-BHSP binding sites in the equine lung represent neur...
Averay K, van Galen G, Ward M, Verwilghen D.Equine small intestinal resection and anastomosis is a procedure where optimizing speed, without compromising integrity, is advantageous. There are a range of different needle holders available, but little is published on the impact surgical instrumentation has on surgical technique in veterinary medicine. The objectives of this study were to investigate if the needle holder type influences the anastomosis construction time, the anastomosis bursting pressure and whether the bursting pressure is influenced by the anastomosis construction time. Single layer end-to-end jejunojejunal anastomoses w...
Constable PD, Tinkler SH, Couëtil LL.To determine the degree of agreement between 2 analyzers for measurement of total CO₂ concentration (ctCO₂) in equine plasma. Methods: 6 healthy untrained horses, 6 trained Standardbreds undergoing a simulated race protocol, and 135 trained Standardbreds at a racetrack. Methods: Jugular venous blood samples were obtained from all horses. Two analyzers (commonly used analyzer A and less expensive analyzer B) were used to measure plasma ctCO₂ in each sample. Validation of both analyzers was conducted in accordance with guidelines established by the Clinical and Laboratory Standards Institu...
Ahlswede L.Future competition horses may suffer from health impairments due to complex or partial genetic components as well as to management faults in respects to keeping, feeding and health prophylaxis against infectious diseases. This health risks exist during the whole rearing period: from late pregnancy till far beyond weaning. Health impairments reduce trade value and practical use, and interfere with aspects of animal protection. In the field of breeding permission, first in stallions, applied research ist needed. For horse farms a praxis-oriented comprehensive advisory service should be establish...
Olivier A, Hood DM, Jenkins WL, Clark DR, Williams JD, Grosenbaugh DA.Interstitial fluid pressures, as a possible function of limb load, were measured at 2 sites within the digital coronary dermis of both cranial digits in 10 standing horses. Fluid pressure changes and digital load measurements were simultaneously detected and recorded by use of, respectively, modified wick-in-needle and force plate transducers coupled to a microcomputer. Mean pressures, recorded at limb loads between 50 and 80 kg, were 2.29 +/- 3.17 mm of Hg at the toe and 2.49 +/- 5.91 mm of Hg at the heel. Mean pressures, recorded between 150 and 180 kg, were 5.01 +/- 5.23 mm of Hg at the toe...
Hanson RR, Nixon AJ, Calderwood-Mays M, Gronwall R.In an attempt to determine the best method for surgical removal of devitalized small colon lesions, 12 horses underwent a double small colon resection and end-to-end anastomosis. In 4 horses (study 1), an appositional single-layer (APP-1) suture pattern was compared with an inverting 2-layer (INV-2) suture pattern. In 8 horses (study 2), an appositional 2-layer (APP-2) suture pattern was compared with the INV-2 suture technique. Polydioxanone suture (size 1-0), was used. Horses were evaluated at necropsy 3, 10, 14, 28, or 56 days after surgery. Postoperative complications (peritonitis, impacti...
Sullivan EK, Parente EJ.Pharyngeal disorders are complex and difficult to treat. Disorders that lead to anatomic derangement, such as trauma and neoplasia, can significantly affect the function of this organ. Pharyngeal dysfunction can manifest as dysphagia, persistent palatal displacement, or exercise intolerance. Secondary complications are serious and life threatening and include aspiration pneumonia, weight loss, and death. Pharyngeal disorders that are only recognizable during strenuous exercise are difficult to diagnose and are treated with limited success, even though they are responsible for significant econo...
Serafini R, Ghosh S, Love CC, Medrano JMR, Teague SR, LaCaze KA, Varner DD.Commercially available vaginal lubricants, typically labeled as non-spermicidal, are used to lubricate equine artificial vaginas prior to semen collection. Improper type or amount of lubricant might affect stallion sperm quality, either after short-time exposure or following cooled storage of extended semen previously exposed to lubricant. The aim of this study was to evaluate stallion sperm quality following exposure to lubricant-containing extender for 1 h (T1h) or 24 h (T24h). Three ejaculates were collected from each of four stallions using a small volume of petrolatum to lubricate a...
Tate LP, Corbett WT, Foreman JH, Bishop BJ, Sweeney CL.A device was constructed of easily obtained medical supplies, and hardware and could be used to obtain multiple arterial samples when manually triggered. The right carotid arteries in five normal horses were surgically elevated, thereby permitting percutaneous cannulation. Each horse was galloped on a 1.6-km test track at approximately 500 m/min, and the rider triggered the mechanism at each 0.4-km mark. Each horse underwent 10 test gallops, and a mean and standard error was determined for each sampling mark including preexercise and postexercise samples. The results indicated that horses ridd...
Hollyer JA, McGuinness E, Bowers LC, Didier ES, Giudice C, Perl DP, Fogarty U.A case of encephalitis of unknown origin in the horse was investigated. Postmortem examination findings revealed a nonsuppurative granulomatous meningoencephalitis in the right hemisphere of the cerebral cortex. Testing for West Nile virus, equine herpes virus, equine infectious anemia, , , and were negative. The horse had a titer for , and sections from the affected area of the brain tested positive for the organism using both polymerase chain reaction (PCR) and immunohistochemistry. Amplicons generated using PCR were sequenced, and genotype II was identified. This is the first case of gen...
Duncan JL, Dargie JD.The migratory route of infective Strongylus vulgaris larvae was determined: penetration of small and large intestine into the lumina of submucosal arteries, migration up the arterial tree, reaching the cranial mesenteric site by three weeks, where the larvae develop to the mature 4th stage. After 3-4 months they exsheath and the young adults migrate down the arteries towards the intestines, to the limit of arterial narrowing, from where they rupture from nodules into the lumen of the intestine. The prepatent period is about 6 months. The clinical syndrome was similar to, but less severe than t...
Rosser J, Brounts S, Slone D, Lynch T, Livesey M, Hughes F, Clark C.Our objective was to compare survival and complication rates of horses undergoing pelvic flexure enterotomy closure with a TA-90 stapler to those with hand-sewn closure. Medical records of horses undergoing pelvic flexure enterotomy between 2001 and 2008 were reviewed. History, clinical signs, surgical findings, surgical techniques, and post-operative complications were recorded. Long-term outcome was established by telephone questionnaire. Of 84 pelvic flexure enterotomies performed, 70 were stapled and 14 were hand-sewn. Seventy-seven horses survived to discharge (91.7%). There were no signi...