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.
Baker D, Kreeger J.An expansile, yellow, soft mass was observed in the free wall of the right ventricle of a 3-year-old, male, Morgan, horse at necropsy. The mass was composed of well differentiated adipocytes in solid sheets or infiltrating between muscle fibers with associated myofiber degeneration. The mass was interpreted to be an infiltrative lipoma of the heart.
Hardee GE, Tshabalala MA, Moore JN, Gokhales RD.Separate high performance liquid chromatographic methods were developed for thiabendazole (TBZ) and 5-hydroxy thiabendazole (5-OH-TBZ) determination in horse plasma using 1-methyl-2-phenyl benzimidazole (MPBZ) as an internal standard. In both methods TBZ and 5-OH-TBZ were extracted from plasma using organic solvents, injected on to a C-18 column, and eluents monitored by a fluorescence detector. However, mobile phase composition, extraction solvent as well as detector wavelength differed in the two methods. The linear range for TBZ was 0.02 to 0.77 microgram ml-1 while that for 5-OH-TBZ was 0....
Denny HR, Barr AR, Waterman A.A series of 25 horses with olecranon fractures are reviewed. Twenty-one cases were treated surgically by the application of a tension band plate to the caudal aspect of the ulna. Seventy six per cent of these regained full limb function. The results of treatment are compared with two other series of conservatively and surgically treated cases.
Magnuson NS, Perryman LE, Wyatt CR, Mason PH, Talmadge JE.Peripheral blood mononuclear cells from foals with hereditary severe combined immunodeficiency (SCID) have morphologic characteristics of large granular lymphocytes (LGL). Attempts to demonstrate cytotoxic activity were without success unless the LGL were incubated with 100 U of human recombinant interleukin 2 (rIL 2)/ml for 24 hr. With rIL 2 incubation, low effector to target ratios (10:1) consistently yielded high levels of cytotoxic activity (30 to 50%) in a standard 4-hr 51Cr-release assay using YAC-1 lymphoma or K562 erythroleukemia cell lines as targets. Monoclonal antibody EqT12 reacted...
Brunson DB, Collier MA, Scott EA, Majors LJ.A monopolar electrode was implanted surgically in the canine tooth dentine layer to evaluate pain threshold responses of horses. A constant-current stimulator was used to deliver a known electrical current to the tooth pulp nerve. A single stimulus of 2-ms duration, repeated at greater than or equal to 20-s intervals, was used to elicit a head lift response. The lowest current level that produced 3 positive head lift responses was recorded as the pain threshold of the horse. The testing technique, dental dolorimetry, was easily performed. Tooth pulp pain thresholds (TPPT) were established on 8...
Dik KJ, Merkens HW.Eleven horses with unilateral distension of the sheath are reported with emphasis on the use of plain and contrast radiography in diagnosis. Six had associated bony abnormalities of the sustentaculum tali, and two of these showed destructive or mixed destructive and proliferative lesions resulting from osteomyelitis. One horse had a fracture of the sustentaculum. In three horses proliferative changes were found. Bony changes were best demonstrated on a dorsomedial-plantarolateral oblique view. Contrast radiography of the tarsal sheath was performed in five cases without, and two horses with, a...
Morris DD.THERE are indications for therapeutic uses of all portions of
whole blood in large animal patients but plasma and its isolated components have the largest number of immediate
applications. As recently as 10 years ago, whole fresh blood
was the only routinely administered blood product. However,
as even cross-match compatible erythrocytes are removed
from circulation within two to four days by the reticuloendothelial system, whole blood is a poor product for expansion of
vascular volume or supplying plasma components if the
patient has no immediate need for increased oxygen carrying
cap...
Plotka ED, Seal US, Eagle TC, Asa CS, Tester JR, Siniff DB.Forty-eight newly captured free-ranging feral stallions (Equus caballus) from two different locations and six captive stallions were immobilized using combinations of etorphine hydrochloride, xylazine hydrochloride and atropine sulfate with or without acepromazine. Six animals were immobilized twice, 1 mo apart. The drugs were administered either intramuscularly (n = 13) or intravenously (n = 44). Mean immobilization time (+/- SE) after intravenous (i.v.) injection of etorphine, xylazine and atropine was 55 +/- 4 sec (range 20 to 185 sec) compared to 708 +/- 131 sec (range 390 to 1,140 sec) fo...
Chirino-Trejo JM, Prescott JF.The antigens extracted from strains belonging to seven capsular serotypes of Rhodococcus equi, as well as from two wild strains isolated from pneumonic foals, were examined. Whole-cell antigens and soluble products present in broth culture supernatants were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, electroblotted onto nitrocellulose, and stained with serum from hyperimmunized rabbits or foals. Foal sera used included sera from pneumonic animals with known titer to equi factors; from animals bled monthly on a farm with enzootic pneumonia, and from animals bled mont...
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.
Bertram JE, Gosline JM.Tensile moduli and J-integral fracture toughness values were determined for horse hoof-wall keratin at four hydration levels. The stiffness of hoof-wall was influenced by water content to a greater degree than is the stiffness of other mammalian hard keratins. Young's modulus increased from 410 MPa at 100% relative hydration (RH) to 14.6 GPa at 0% RH. Fracture toughness was maximal (22.8 kJ m-2) at an intermediate hydration (75% RH), which represents a two-fold increase over both fully hydrated and dehydrated material. Maximum fracture toughness occurred at a hydration level which is within th...
Yovich JV, Turner AS, Stashak TS, McIlwraith CW.Lateral or medial luxation of the metacarpophalangeal or metatarsophalangeal (fetlock) joint in 10 horses is presented. Closed and open fetlock luxation each occurred in five horses. Horses were treated by cast immobilisation after debridement of soft tissue and joint lavage in cases of open luxations. Suture apposition of a ruptured collateral ligament was attempted in three cases. Antibiotic therapy was used in all cases of open fetlock luxation but non-steroidal anti-inflammatory medication was used inconsistently. Whether closed or open, fetlock luxations had a good prognosis for return to...
Markel MD, Snyder JR, Hornof WJ, Meagher DM.Nuclear scintigraphy was used to evaluate healing of third metacarpal bone (MC III) fractures in 2 horses (horses 1 and 2) and a third metatarsal bone fracture in 1 horse (horse 3) after stabilization of each fracture with 2 broad dynamic compression plates. In horse 1, the fracture had uniform uptake of 99mTc methylene diphosphonate on days 1, 15, and 30 after surgery. The fracture healed, and the horse was discharged from the clinic on day 52. In horse 2, a 6-cm photopenic region (ie, area of low radioactivity) was seen over the diaphysis of MC III on day 3. The region persisted and became m...
Munson L.A 17-year-old Quarter Horse mare developed rapidly progressive, bilateral, firm enlargements of both mammary glands, ventral abdominal edema, dyspnea, and neurologic signs. The horse was euthanatized, and a carcinoma of the mammary gland was diagnosed at necropsy. Microscopically, normal glandular parenchyma was replaced by neoplastic nodules, and the tumor had metastasized to most visceral organs and throughout the musculoskeletal and central nervous systems. The tumor had a solid pattern, with microglandular differentiation, and numerous syncytial sheets.
Grandy JL, Steffey EP, Miller M.Arterial blood was collected from 25 clinically normal horses immediately before and serially throughout the first hour of halothane oxygen anaesthesia. Blood was analysed for oxygen and carbon dioxide partial pressure (PaO2, PaCO2). Measurements of inspired oxygen concentration during anaesthesia permitted direct correlation with blood gases. Horses were divided arbitrarily into two groups based on their age: two to seven years, n = 15; over seven years, n = 10. Average (+/- sd) PaO2 and PaCO2 was 14.1 +/- 1.5 kPa (106 +/- 11 mmHg) and 5.9 +/- 0.6 kPa (44.4 +/- 4.4 mmHg) respectively in consc...
Satterlee JD, Moench S.Proton hyperfine resonance assignments for cytochromes c from several species are currently being successfully pursued by several laboratories. These efforts focus mostly on the ferrous forms. In contrast to that work, we have pursued assignments of the proton hyperfine shifted resonances for horse and tuna ferricytochromes c. Our results indicate that assignments are nearly identical in those two proteins. Using the pre-steady state nuclear Overhauser effect, several additional assignments have been made for the tuna protein, whereas for the horse protein, the following protons have been assi...
Enileeva NKh.The paper describes the flight periods and dynamics of abundance of horse botflies, life span of females and males, effect of environmental factors on the activity of flies and their behaviour, potential fecundity of different species of botflies, duration of embryonal development, preservation of viability of larvae in egg membranes, localization of different stages of botflies in the host, and methods of their control.
Bernard W, Divers TJ, Whitlock RH, Messick J, Tulleners E.Clostridium botulinum and type-B C botulinum toxin were isolated from a necrotic wound that developed subsequent to castration in a 2-year-old Thoroughbred gelding. The horse had clinical signs of botulism and was successfully treated with wound debridement, C botulinum type-B antitoxin, potassium penicillin, and supportive care.
Sletten K, Husebekk A, Husby G.The amino acid sequence of the amyloid fibril protein AA from horse was established from characterization of cyanogen bromide fragments, tryptic peptides, and a peptide derived from a digest with Staphylococcus aureus V8 proteinase. The protein was found to consist of 80 amino acid residues. Sequence homologies with protein AA from other species were very striking, and revealed an insertion of two amino acid residues between positions 72 and 73. In position 44, two amino acid residues were found which provide further evidence for a polymorphism in the amyloid fibril protein AA.
Garcia MC, Ganjam VK, Blanchard TL, Brown E, Hardin K, Elmore RG, Youngquist RS, Loch WE, Ellersieck MR, Balke JM.Fifty 2- to 16- yr old pony stallions were randomly assigned to one of five treatments: Group 1, controls (no treatment); Group 2, 0.55 mg/kg stanozolol weekly for 13 treatments; Group 3, 1.1 mg/kg stanozolol every 3 wk for 5 treatments; Group 4, 1.1 mg/kg boldenone undecylenate every 3 wk for 5 treatments; and Group 5, 0.55 boldenone undecylenate weekly for 13 treatments. Mean plasma testosterone levels for Groups 2, 4, and 5 were elevated over controls (P0.05). There were no differences in mean plasma luteinizing hormone (LH) and follicle stimulating hormone (FSH) levels among groups (P>0...
Higgins AJ, Lees P, Sharma SC, Taylor JB.An accurate and reliable method for the separation of flunixin from, and measurement in, equine inflammatory exudate and plasma by high performance liquid chromatography has been developed. Flunixin can be detected in concentrations as low as 0.05 micrograms/ml using an ultraviolet spectrophotometric detector at 285 nm. Samples were acidified with 2M hydrochloric acid and extracted with dichloromethane. The extract was evaporated and reconstituted in acetonitrile. Iminodibenzyl was used as internal standard. The mean recovery of flunixin from plasma was 97.6 +/- 3.9 per cent. Particular advant...
Craig D, Todhunter R.An esophageal stricture was diagnosed in a 9-month-old quarterhorse by esophagoscopy and positive pressure contrast esophagography. Medical management and two attempts at surgical intervention were unsuccessful. The initial surgical technique used was a linear esophagotomy, mucosal resection and anastomosis, and closure of the muscular tunic, which resulted in a more severe stricture. The second surgical procedure was interruption of the stricture cicatrix by a single linear esophagotomy and primary closure of only the esophageal muscular tunic. This technique resulted in an increased lumen di...
Waelchli RO, Winder NC.Endometrial biopsies were obtained from four mares during consecutive oestrous cycles on the first day of oestrus, on the day when ovulation was detected, and four and eight days after ovulation. Cycle stages were confirmed by means of rectal palpation, ultrasonography and plasma progesterone determination. Immunohistochemical evaluation of the formalin fixed biopsy specimens was performed using a peroxidase anti-peroxidase technique. Immunoglobulin (Ig)A-, IgM-, IgG(Fc)- and IgG(T)-containing cells were detected in all biopsies; with IgA- and IgG(Fc)-containing cells generally predominating. ...
Houghton E, Dumasia MC.1. After intramuscular administration of [4-14C]testosterone to two cross-bred gelded horses, 45% of the radioactivity was excreted in urine in 96 h. Small amounts of urinary activity could still be detected at 200 h. 2. Neutral metabolites obtained after both enzyme and acid hydrolysis of urine samples have been investigated by g.l.c.-mass spectrometry. 3. 5 alpha-Androstane-3 beta, 17 alpha-diol was found only in the enzyme-hydrolysable extract and testosterone only in the acid-hydrolysable extract. 5 alpha-Androstane-3 beta, 17 beta-diol and 3 beta-hydroxy-5 alpha-androstan-17-one were foun...
Scherzer J.Reproductive performance in mares can be enhanced by various techniques. Protocols hastening the onset of follicular development help establish pregnancy in mares and ensure that foals are born early in the year. The time spent breeding mares can be reduced by synchronizing estrus and inducing ovulation. After successful fertilization of the oocyte, the developing embryo can survive in the uterus only if postbreeding endometritis, if present, is treated.
Löfqvist L, Pinzke S.The horse industry in Sweden has rapidly expanded in recent years. This increasing number of horses implies a greater need for more farriers. Shoeing a horse is hard physical work, and includes awkward work postures and repetitive movements. It is well known that hard physical work increases the risk of injuries and musculoskeletal problems. The risk is especially high for musculoskeletal disorders when certain movements are constantly repeated. Heavy or repeated unilateral loads lead to considerable stress on the muscles, which can lead to rupture and fatigue that can cause long term problems...
Reiwald D, Riond JL.The copper and zinc contents of 25 rations for adult horses were evaluated. The total amount of copper and zinc daily ingested was obtained by adding the amount of each element contained and added of the commercial feed to the amount contained in ingested hay and oats. The total amount of copper and zinc ingested daily was compared with the official recommendations for the maintenance of an adult horse of 550 kg. The results show that a traditional ration oats/hay does not contain a sufficient amount of copper and zinc in order to cover their respective requirements. Furthermore, many rations ...
Sheta E, Farghali H, Ragab S, Hassan N, El-Sherif A.Twenty-five Thoroughbred jumper geldings suffered back soreness with poor performance, and 5 control horses were assessed by archived computer data, clinical examination, and laboratory analyses of complete blood picture, serum enzymes, and cortisol level, before and after cloprostenol-pharmacopuncture. The 25 diseased horses before therapy showed significant increases in aspartate aminotransferase and creatine phosphokinase with clinical pains scored mild in 15 horses, moderate in 9 horses, and severe in one horse, without changes in the hormonal and hematological data. After therapy, they re...
Horohov DW, Keadle TL, Pourciau SS, Littlefield-Chabaud MA, Kamerling SG, Keowen ML, French DD, Melrose PA.Intense exercise affects various parameters of the immune system. The overall effect of exercise on immune function is dependent upon the physical condition of the subject, the intensity and duration of the exercise period, and the immune parameter assessed. Unconditioned horses subjected to a single bout of intensive exercise exhibit multiple alterations in immune function, including an augmentation of lymphokine activated killer (LAK) cell function. This increase in LAK cell activity is not due to an increase in circulating LAK precursors. While peripheral blood mononuclear cells from exerci...
Montgomery JB, Duckett WM, Bourque AC.A 6-year-old mare was presented for evaluation of dysuria and pollakiuria. A pelvic mass, which caused obstruction of urinary outflow, was identified. Evidence of renal failure was also present. Due to poor prognosis the mare was euthanized. A postmortem examination revealed a pelvic lymphoma that surrounded and compressed the urethra. Lymphome pelvien comme cause de compression urétrale chez une jument. Une jument âgée de 6 ans est présentée pour évaluation de dysurie et de pollakiurie. Une masse pelvienne qui causait l’obstruction de l’écoulement d’urine a été identifiée. Des...
Matthews NS, Lindsay SL.Minimum alveolar concentration (MAC) for halothane was measured before and after administration of intravenous butorphanol (0.022 and 0.044 mg/kg in bodyweight in nine yearling Shetland ponies. Arterial blood pressure, heart rate, respiratory rate, expired CO2 and rectal temperature was also measured. Even though mean MAC values decreased 10 and 9 per cent after the low and high doses respectively, they were not statistically different from those measured prior to butorphanol. Halothane MAC values increased after butorphanol in two ponies, both animals increasing locomotor activity and demonst...
Richardson DW, Dodge GR.The complete nucleotide sequence of equine type II procollagen has not been previously reported, and equine-specific probes have not been available. We report the complete sequence and discuss the molecular characteristics of equine type II procollagen mRNA which was cloned from a cDNA library prepared from mRNA isolated from equine articular chondrocytes. The coding sequence (4257 bp) was 92.4% homologous to the cDNA of the human sequence, and the propeptide was 97% identical to the human sequence. We demonstrated that when equine chondrocytes are grown in phenotypically-maintained cultures, ...
Thirumalapura NR, Livengood J, Beeby J, Wang W, Goodrich EL, Goodman LB, Erol E, Tewari D.Neorickettsia risticii, an obligate intracellular bacterium, is the causative agent of Potomac horse fever (PHF). Diagnosis of PHF is based on demonstration of serum antibodies, isolation of N. risticii, and/or detection of nucleic acid by a PCR assay. An existing real-time PCR assay targeting the N. risticii 16S rRNA has been validated using blood samples from horses with colitis, and snails; to our knowledge, the performance of the assay for other sample types has not been reported. We describe here a modification of the 16S rRNA gene assay by the addition of a set of primers and probe targe...
Petzoldt K, Merkt H, Müller E, Kirpal G.Over the last years the percentage of foals lost by EHV at term or close to term seems to be higher than in former years. Furthermore, the pathological findings seem to shift from liver to lung. So far there has been no explanation for this phenomenon.
Sullins KE.Common equine upper respiratory conditions are diagnosed via endoscopy. Endoscopic surgery facilitates correction of many conditions without general anesthesia or laryngotomy, reducing the morbidity and cost of the procedures. Modalities of endoscopic surgery include the Nd-YAG laser or electrosurgery, which may be complementary. The least expensive method is electrosurgery, and instruments are available that can be passed through the biopsy channel of the endoscope. Conditions amenable to such procedures include entrapped epiglottis, rostral displacement of the palatopharyngeal arch, pharynge...
Berghuis GA, Wesselink HG.Twenty nine mares with retained fetal membranes were treated IV with an oxytocine infusion. Within two hours the placenta released in 24 mares (83%). Twenty six (90%) mares got pregnant during the same season.
Physick-Sheard PW, Morris WI, Genner D.To evaluate the clinical application of a semiorthogonal lead system for use in the horse, an inexpensive means of recording and storing the ECG was required which would allow the subsequent vectorcardiographic analysis to be computerized. In investigating the various options for the system the basic requirements for the digitization of analogue data were reviewed and previous studies examined. The system subsequently developed used an 8080 microprocessor and a multichannel 8-bit analogue to digital converter. This unit was signal-level compatible with the laboratory recorder used in the study...
Nash RA, Nunamaker DM, Boston R.To evaluate stiffness and bone-pin interface stress for a transcortical tapered-sleeve pin (TSP) that incorporates bilateral tapered sleeves over a transcortical pin. Methods: 14 third metacarpal bones (MCIII) collected from adult horses of various breeds. Methods: Each MCIII was cut in half to provide 2 test specimens. Pins (conventional and TSP) of 3 diameters (6.35, 7.94, and 9.50 mm) were inserted in specimens (3 specimens for each diameter and each type of pin). The test fixture simulated a typical sidebar-span skeletal fixation device for horses. Single cycle load-deflection tests were p...