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.
Taylor PM.Information on equine stress responses to anaesthesia and surgery is sparse. Six ponies were anaesthetized for 2 h with halothane and no surgery was performed. Plasma concentrations of glucose, lactate, non-esterified fatty acids, cortisol, insulin, catecholamines and adrenocorticotropic hormone (ACTH) were measured. The results were compared with those obtained in the same group of ponies over the same time period on a different day with the animals conscious. Anaesthesia induced an increase in plasma concentrations of glucose, lactate, cortisol and ACTH and a decrease in plasma concentration...
Sweeney CR.Tracheal mucus transport rates were measured over a 10-minute period in 20 healthy horses twice in 24 hours. The mean rate was 1.93 +/- 0.55 cm/min on day 1 and 1.99 +/- 0.49 cm/min 24 hours later. The mean difference between day 1 and day 2 (0.06 +/- 0.42 cm/min) was not significant (P = 0.55). The range on day 1 was 1.12 to 2.9 cm/min and 1.11 to 2.89 cm/min on day 2.
Hellyer PW, Bednarski RM, Hubbell JA, Muir WW.Baroreflex sensitivity (BS) was used to quantitatively assess the effects of halothane and isoflurane on the heart rate/arterial pressure relationship during steady-state (10 minutes) and dynamic pressure changes in adult horses. Arterial pressure was decreased in response to nitroglycerin or sodium nitroprusside and increased in response to phenylephrine HCl. Mean (+/- SEM) BS in awake horses was 28.9 +/- 2.6 and 13.2 +/- 2.0 ms/mm of Hg during steady-state decreases and increases in systolic arterial pressure (SAP), respectively. Halothane and isoflurane either significantly (P less than 0.0...
Galey FD, Beasley VR, Schaeffer DJ, Davis LE.Prazosin, isoxsuprine, and nifedipine were screened for ability to reverse contraction of isolated equine digital vascular strips produced by epinephrine (Epi) in the presence of hydrocortisone (Hc) and an aqueous extract of black walnut (Juglans nigra) (BW). Two arteries and two veins from each of three horses for each drug (n = 9) were maintained in isolated tissue baths in Krebs' bicarbonate buffer with 95% oxygen at 37 degrees C. Six-point Epi concentration-response (C-R) curves were obtained for each vessel in the presence of Hc, BW, and the appropriate vehicle. This was repeated for each...
Stadler P, van Amstel SR.The results of a study conducted to determine the clinico-pathological changes in 4 experimentally-induced cases of endotoxaemia in the horse are reported on. Endotoxaemia was induced by injecting commercially available E. coli 055:B5 lipopolysaccharide intravenously at a dose of 1 microgram kg-1. The haematocrit, red cell count, total and differential white cell counts, thrombocyte count, prothrombin time, partial thromboplastin time, fibrinogen level, level of fibrin degradation products, arterial acid-base status, serum lactate and blood glucose were determined repeatedly. Changes that occu...
Kettler MK, Weil MR, Perryman LE.Serum uric acid concentrations were determined in horses known to be carriers of combined immunodeficiency gene(s) and in presumed noncarrier horses. Uric acid concentrations were significantly higher (P less than 0.005) in carrier horses than in presumed noncarrier horses. However, there was some overlap in serum uric acid concentrations between carrier and presumed noncarrier horses.
Sarazan RD, Starke WA, Krause GF, Garner HE.The cardiovascular effects of detomidine and xylazine were compared in six chronically instrumented, conscious ponies. Ponies were instrumented with a micromanometer in the left ventricular chamber, a Doppler flow probe on a coronary artery and sonomicrometer crystals in the left ventricular free wall. Heart rate, ventricular systolic pressure, stroke work, dP/dtmax, minute work and coronary blood flow were measured for 4 h following intravenous injection of detomidine at several doses or xylazine at 1.1 mg/kg. Both drugs caused a profound hypertensive response at 15 s post-injection. The magn...
Bertone AL.Second-intention healing (contraction and epithelization) is most appropriate for heavily traumatized, contaminated wounds that may have a prolonged debridement phase. Therapy during healing can promote rapid debridement and faster healing. Healing of lower limb wounds by second intention may be protracted, owing to poorer wound contraction and excessive granulation tissue production as compared with body wounds.
van Rensburg IB, Stadler P, Soley J.A bronchiolo-alveolar adenocarcinoma was diagnosed in the lungs of a horse which was euthanased after protracted respiratory disease and radiological evidence of pulmonary neoplasia. Multifocal, large, firm neoplasms occurred throughout both lungs. Neoplastic lesions were not found elsewhere. Histologically the bronchiolar and alveolar architecture was retained. The cuboidal cells lining neoplastic alveoli had very vacuolated cytoplasm, while some were ciliated. Electron microscopy identified the cells as Type II pneumocytes. Numerous distended myelinoid bodies in the tumour cells accounted fo...
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...
Rice NR, Lequarre AS, Casey JW, Lahn S, Stephens RM, Edwards J.The amount and distribution of viral DNA were established in a horse acutely infected with the Wyoming strain of equine infectious anemia virus (EIAV). The highest concentration of viral DNA were found in the liver, lymph nodes, bone marrow, and spleen. The kidney, choroid plexus, and peripheral blood leukocytes also contained viral DNA, but at a lower level. It is estimated that at day 16 postinoculation, almost all of the viral DNA was located in the tissues, with the liver alone containing about 90 times more EIAV DNA than the peripheral blood leukocytes did. Assuming a monocyte-macrophage ...
Bertone AL.Exuberant granulation tissue is common in large, lower limb wounds of horses, particularly horses of large body size. Methods of control include chemical cautery, cryogenic surgery, and surgical resection. Surgical resection is preferred because it is easy to perform, provides tissue for histologic evaluation, and preserves the epithelial margin. Effective treatments to prevent the formation of granulation tissue include leaving granulating wounds open to the air or, possibly, bandaging with topical steroids. Bandaging or casting may promote exuberant granulation tissue in wounds in which it h...
Freeman DE, Kleinzeller A, Donawick WJ, Topkis VA.When sheets of mucosa from the cecum of clinically normal horses were incubated in vitro with radiolabeled L-alanine, they could accumulate this amino acid against an apparent concentration gradient after 60 to 150 minutes of incubation. The active transport system for L-alanine was on the serosal surface of the mucosal sheet only. L-Alanine accumulation at 60 minutes was partly inhibited by 20 mM glycine (P less than 0.01), 0.5 mM ouabain (P less than 0.05), and Na deprivation (P less than 0.02). Anoxia for 60 minutes increased L-alanine accumulation, but had adverse effects on cell structure...
Trotter GW.Although many wounds in horses heal successfully by second-intention healing or delayed closure, some wounds can be sutured primarily, with reasonably high expectations of first-intention healing. To expect to achieve these results, one needs to have a rational treatment plan. Such a plan should be based on a working knowledge of the biology of tissue repair and tissue infection. Treatment decisions should be based more on results of experimental and clinical trials rather than on testimonials of other practitioners.
Saari H, Konttinen YT, Tulamo RM, Antti-Poika I, Honkanen V.In addition to its well-known physicochemical properties, hyaluronate (HA) has recently been shown to have important biological and pathophysiologic regulatory effects on granulocytes, monocytes, fibroblasts, and endothelial cells, as well as on the healing of wounds and various joint disorders. Many of these effects depend on or are reflected in the concentration and degree of polymerization of HA. Therefore, high-performance liquid chromatography with size-exclusion column was used to characterize the concentration and degree of polymerization of HA in equine synovial fluid (SF). The mean (+...
Grandy JL, Hodgson DS, Dunlop CI, Chapman PL, Heath RB.The cardiopulmonary effects of intravenous (i.v.) administration of the sympathomimetic drug ephedrine during two different levels of halothane anesthesia [end-tidal concentration of 1.37% (light anesthesia) and 2.1% (deep anesthesia)] were studied in eight horses. Anesthesia was induced and maintained using only halothane in O2. Ventilation was controlled to maintain a Paco2 of 38-42 mmHg. Following instrumentation and stabilization of the horse at the halothane concentration being studied, baseline measurements of cardiac output (Q), arterial blood pressure (AP), pulmonary artery pressure, h...
Fessler JF.Major surgery for wounds of the foot, compared with other parts of the body, requires a more detailed preparation and a more persistent aftercare. To approach severe hoof wounds with a routine applicable to drainage of a subsolar abscess is doomed to failure! Yet, in dealing with referral cases of hoof wounds, particularly those that have become chronic, the author has observed that the principles have been ignored and/or the routines inadequate. The hoof has a suitable capacity to heal, with complete reformation of hoof structures, if a healing environment is maintained for a long enough peri...
Boyd EH, Allen WE.Plasma drug concentrations were measured after two commercially available potentiated sulphonamides, trimethoprim and sulfadoxine and trimethoprim and sulphadiazine, were infused daily for 2 and 3 days, respectively, into the uteri of pony mares which had been mated before ovulation. Intravenous administration of trimethoprim and sulfadoxine allowed uterine absorption of trimethoprim (23-43%) and sulfadoxine (29-34%) to be calculated. After intra-uterine administration trimethoprim and sulphadiazine were detected in the milk of a lactating mare. In order to maintain plasma concentrations likel...
Dumasia MC, Houghton E.The research investigates the biosynthesis of a particular isomer called 5(10)-estrene-3 alpha, 17 beta-diol in stallion testes and how it affects the formation of 19-nor steroids and oestrogens. Summary of […]
Morris DD, Henry MM, Moore JN, Fischer K.In laboratory animals, the incorporation of alpha linolenic acid or other n-3 series fatty acids into the diet results in marked changes in cell membrane composition as well as arachidonic acid metabolism. The purpose of the present study was to determine whether endotoxin-induced thromboxane A2 (TxA2) and/or prostacyclin (PGI2) production by equine peritoneal macrophages was altered by feeding horses a diet containing 8% linseed oil as a source of alpha linolenic acid for 8 weeks. Peritoneal macrophages were cultured in vitro in the presence of endotoxin (LPS) (0.5-500 ng/ml) or calcium ionop...
Goetz TE, Munsiff IJ, McKiernan BC.The pharmacokinetic disposition of theophylline was determined by high-performance liquid chromatographic analysis of plasma samples from six healthy, adult horses following the administration of intravenous aminophylline (dosed at 9.94 mg/kg as theophylline), immediate-release aminophylline tablets (dosed at 9.94 mg/kg as theophylline), and sustained-release theophylline tablets (dosed at 20 mg/kg). The elimination rate constant (lambda z), apparent volume of distribution (Vz), and clearance (Cl) determined by compartmental analysis of the intravenous data were 0.07 +/- 0.01 h-1, 0.80 +/- 0.0...
Van Amstel SR, Ross M, van den Bergh SS.A case of maduromycosis mycetoma caused by Madurella mycetomatis is reported. The horse presented with multiple subcutaneous swelling over the right scapula. There were no discharging fistulae present. Macroscopically the lesion contained a black granular material embedded in a granulomatous mass. Microscopically large numbers of microcolonies were present containing segmented hyphae. No typical chlamydospores were observed. Cultures yielded a fungus identified as Madurella mycetomatis. Treatment consisted of surgical excision and local treatment with thiabendazole powder.
Gutierrez CV, Riddle WT, Bramlage LR.To determine whether serum thyroxine (T4) concentration was associated with pregnancy rates 15 to 16 days after ovulation in mares and to determine whether thyroid hormone supplementation would enhance fertility in mares. Methods: Cohort study. Methods: 329 clinically normal broodmares. Methods: Mares were examined 15 to 16 days after ovulation to determine whether they were pregnant; blood samples for determination of serum T4 concentration were collected at the same time. Sixty mares were receiving thyroid hormone supplementation prior to the study because of low serum T4 concentration (< 16...
Argenzio RA, Hintz HF.Factors affecting glucose tolerance and the effect of volatile fatty acids on plasma glucose were studied with five ponies in two 5×5 latin square trials. The treatments were equimolar infusions of glucose, acetate, propionate, butyrate and isontonic saline in fed or fasted ponies.
Animals fasted for 72 hr. exhibited a markedly lower glucose tolerance than those fed ad libitum. Propionate appeared to be the only VFA stimulating a significant glucose response in the fasted animals, but no response was noted in the fed animals. The data suggest that length of fast is an important variable in...
Mäkinen A, Katila T, Kuokkanen MT.Only one X chromosome was found in each of the lymphocyte metaphases studied in an infertile mare. Karyotype analysis was made with the CBG and GTG banding techniques. The most obvious clinical abnormality was gonadal hypoplasia.
Medeiros LO, Medeiros LF, Barcelos SR, Ferri S, Reiner UR.
Summary:
The authors studied glycolytic and non-glycolytic erythrocytic enzyme activities in 8 thoroughbred horses with equine infectious anemia (EIA) and 16 normal controls. Biochemical lesions were indicated, the most outstanding being a deficiency of pyruvatekinase. Adenvlatekinase could be considered as a “salvage pathway” for the formation of ATP.
Zusammenfassung:
Infektiöse Anemie bei Pferden Mangel an Pirovatokinase in Erythrocyten der Englischen Vollblutpferde
Die Autoren untersuchten die Aktivität der glykolytischen und der nichtglykolytischen Enzyme der Erythrocyt...
Moriarty KM, Brown MF, Sutton RH.Auto-immune, haemolytic anacmias (AHA) of man (Dacie, Citation1963) and domestiicated animals (Schalm, Citation1965; Farrelly et al., Citation1966; Lapras and Oudar, Citation1971) are classified either as idiopathic or secondary to an underlying disease process (Pirofsky, Citation1969). In both categories antibodies active against the indivual's own erythrocytes are formed. These auto-antibodies are of two types being either warm or cold-acting. Warm-acting antibodies are most effective at 37°C, belong to the IgG class of immunoglobulins, and are incomplete in that, generally, they do not cau...
Zantingh AJ, Gaughan EM, Bain FT.A 14-year-old Hanoverian gelding was evaluated after a 10-week history of occasional straining during urination and dark red urine production after exercise. Physical examination findings were within normal limits. After 2 weeks of clinical signs, ultrasonography had found no abnormalities in the kidneys or bladder. A freely voided urine sample revealed an elevated protein concentration (500 mg/dL; reference range: <100 mg/dL) and few red blood cells. Vitamin C supplementation was suggested to acidify the urine, as was provision of a salt block to encourage water intake.
Rossdale PD.Diagnosis in veterinary medicine is based upon observations of the manner in which the behavioural patterns differ from those exhibited by normal subjects. The newborn foal adapts to an advanced level of activity within a period which is short relative to many other species, and the behavioural patterns which it exhibits during the period of adaptation are comparatively stereotyped. Because the status of any newborn mammal is affected by its previous experience of foetal development and birth, the behavioural patterns of the mother form an important anamnesis in the life of each individual neo...
Moorthy AR, Spradbrow PB.
Summary:
During a survey in Queensland in 1974—77 four strains of rickettsia-like organisms were isolated from the respiratory tract of horses, of which two, NS7 and NS68 were isolated from nasal swabs of clinically normal horses and two, KSDH 91 and NSDH 100, from lung samples of slaughtered horses showing gross pathological lesions in the form of acute bronchiolitis and subacute interstitial pneumonia, respectively. The isolates are characterised as rickettsia-like organisms on the basis of their morphology, tinctorial property, growth in chicken embryos, inability to grow on bacteria...
Beadle RE, Short CR, Corstvet RE, Pawlusiow J, Nobles DD, McClure JR, Guthrie AJ, Clarke CR.A soft-tissue infection model was created in eight horses by infecting subcutaneous tissue chambers with Streptococcus zooepidemicus organisms. Responses of the horses to the infections were determined by monitoring changes in the complete blood count and body temperature and by following changes in the cytology and protein content of the tissue chambers. Systemic reactions to the infections included a mild neutrophilia, mild pyrexia and mild anemia. There was a marked influx of neutrophils and protein into the chambers after they were seeded with bacteria and chamber neutrophil viability decr...
McKay AG, Milne FJ.A project to determine if intraarticular corticosteroid therapy was deleterious to the racing Thoroughbred was carried out in the 1971, 1972, and 1973 racing seasons. Of 22 horses available for follow-up examination, 6 had radiographic evidence of deterioration; 1 of these was destroyed because of probable corticosteroid-induced arthropathy. The remaining 16 horses did not have any evidence of deterioration. One of the 16, a stakes winner, had been given 12 injections into the left front fetlock during the 3-year period. It was concluded that if proper and careful aftercare is adhered to, intr...
Smith LH, Adams L, Derré M, Townsend WM.To describe the successful use of endoscopy to visualize and place a soft canine ureteral stent to relieve a chronic nasolacrimal duct (NLD) obstruction in a horse. Methods: A 7-year-old, Quarter horse gelding. Methods: Under general anesthesia, retrograde nasolacrimal endoscopy was performed using an 8.5 Fr Storz Flex XC ureteroscope through the nasal punctum (NP). An obstructive web of fibrous tissue was visualized approximately 20 cm proximal to the NP. A 0.035″/150 cm hydrophilic guidewire was passed normograde from the ventral lacrimal punctum and used to puncture the stenotic tissu...
Nyack B, Padmore CL, Dunn D, Kufuor-Mensan E, Mobini S.A 10-year-old Tennessee Walker gelding, with a history of progressive weight loss, intermittent colic and lethargy, had a slight fever, tachycardia, tachypnea, pallor, ascites and marked ventral edema. Blood analyses revealed anemia, leukocytosis, neutrophilia with a left shift, lymphopenia, monocytosis, hypoproteinemia and a slightly increased SDH level. Abdominocentesis produced red-orange fluid with many RBC and an increased fibrinogen content. Rectal palpation revealed a large mass in the left caudal abdominal quadrant. The animal died shortly after resection of the mass. The histopatholog...
Schubert B.Some chromatographic procedures, which can be used to detect and determine certain corticosteroids in samples from race horses, are described. These procedures include thin-layer, gas and high pressure liquid chromatography.
Losinger WC, Traub-Dargatz JL, Sampath RK, Morley PS.Of 7320 equine foals reported born alive during 1997 on 1043 operations that had equids on 1 January 1997, and that participated in the United States National Animal Health Monitoring System (NAHMS) Equine 1998 Study, 120 foals were reported to have died (by either euthanasia or natural causes) within the first 2 days of a live birth. The weighted estimate was 1.7% mortality (standard error=0.5) within the first 2 days of live birth for all foals born on operations in the 28 states included in the study.A multivariable logistic-regression model revealed that foals born in the southern region w...
Dumasia MC, Houghton E.The in vivo biotransformation of (1,2(n)-3H)1-dehydrotestosterone was studied in three equine male castrates and a number of neutral metabolites were identified in the urinary unconjugated and glucuronic acid conjugate fractions by gas chromatography/mass spectrometry. The metabolites were extracted from aliquots of the 0-24 h urine samples by Amberlite XAD-2 and separated into combined unconjugated plus glucuronic acid conjugated and sulphoconjugated fractions by Sephadex LH-20 column chromatography. After enzymatic hydrolysis of the glucuronides, the crude neutral unconjugated steroids plus ...
Gilger BC, Histed J, Pate DO, Clode AB, McMullen RJ.This case report describes the clinical, diagnostic, computed tomography findings, and surgical treatment of a 2-year-old Morgan filly with bilateral, proximal, and distal anomalous nasolacrimal duct openings.
Drews B, Milojevic V, Robles M, Wimel L, Dubois C, Rudolf Vegas A, Giller K, Chavatte-Palmer P, Daniel H, Giesbertz P, Bruckmaier RM, Ulbrich SE.Female mammalian reproductive functions are closely linked to body condition and metabolic status. Energy homeostasis is regulated by endocrine hormones such as insulin, IGF-I, leptin, and adiponectin via the hypothalamic-pituitary-adrenal axis. These metabolic hormones and their receptors are also expressed in reproductive tissues and the embryo. We investigated the relationship between circulating leptin and the fatty acid (FA) and amino acid (AA) composition of the equine uterine fluid (UF) and peripheral blood plasma (BP) by using a mass spectrometry-based approach. UF and BP were collecte...
Czernomysy-Furowicz D, Silecka A, Nawrotek P, Jankowiak D, Karakulska J, Furowicz A.The research was conducted on clinically healthy mares (n = 40) and foals (n = 78) during Y. pseudotuberculosis associated enzootics. The animals were divided into groups: I to IV--mares, IA to IVA--their offsprings, IB to IVB--foals which mothers were not treated with any medicaments. The animals in group I, IA and IB were injected with PBS; in group II, IIA and IIB--with Y. pseudotuberculosis strain-based vaccine, in group III, IIIA and IIIB--with P. acnes strain-based immunostimulator; in group IV, IVA and IVB--with P. acnes strain-based immunostimulator and (5 days after the immunostimulat...