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.
Kaminski RP, Forster HV, Bisgard GE, Pan LG, Dorsey SM.The objective was to determine the effect of moderate changes in ambient temperature (TA) on breathing and body temperature in ponies chronically exposed to a TA of 21 degrees C in the summer and 5 degrees C in the winter. Normal (n = 6) and chronic carotid body-denervated (n = 6, 1-2 yr) ponies were studied during 1) winter months over 3-4 days at 5 (control TA) and 23 degrees C and 2) summer months over 2-4 days at 21 (control TA), 30, and 12 degrees C. Neither rectal nor arterial temperature changed with any alteration of TA (P greater than 0.10). Skin temperature (Tsk) always changed by 2-...
Foil L, Stage D, Adams WV, Issel CJ.The occurrence of tabanid feeding between mares and foals was observed. When mares and foals were observed freely moving within a pasture situation, foals had 2.43% (4 flies in 77 observations vs 297 flies in 139 observations) of the tabanid feeding occurrences of the mares. This difference in tabanid burden varied due to herd size, herd location, and tabanid species. Lower tabanid burden of foals was indicated as a practical protective mechanism against pathogenic agents mechanically transmitted by tabanids, such as equine infectious anemia virus.
Leid RW, Coley SC, Blanchard DP, Perryman LE.The equine alternative complement pathway has been partially characterized and compared to the equine classical activation pathway. A dose-dependent lysis of RbRBC was observed with peak lytic values noted within 10 minutes at 37 degrees C when rabbit red blood cells (RbRBC) were used as an alternative pathway activator. Sheep red blood cells (SRBC) sensitized with rabbit hemolysin or partially purified equine IgM antibodies were equally sensitive to lysis. Dilution of the commercial hemolysin by 1/5 reduced lysis from 90% to 38% in the presence of constant cell numbers. Hemolysis of SRBC peak...
Kaminski RP, Forster HV, Bisgard GE, Pan LG, Dorsey SM, Barber BJ.The purpose of this study was to determine if the changes in O2 consumption (VO2) during CO2 inhalation could in part be due to stimulation of thermogenesis for homeothermy. Twelve ponies were exposed for 30-min periods to inspired CO2 (PIco2) levels of less than 0.7, 14, 28, and 42 Torr during the winter at 5 (neutral) and 23 degrees C ambient temperatures (TA) and during the summer at 21 (neutral TA), 30, and 12 degrees C. Elevating TA in both seasons resulted in an increased pulmonary ventilation (VE) and breathing frequency (f) (P less than 0.01) but no significant increase in VO2 (P great...
Spurlock GH, Landry SL, Sams R, McGuirk S, Muir WW.Plasma volume, extracellular fluid volume (ECFV), and total body water (TBW) were measured before and after endotoxin (Escherichia coli) administration in 6 conscious adult horses. Evan's blue dye, sodium thiocyanate, and antipyrine were the test substances used to estimate plasma volume, ECFV, and TBW, respectively. Pharmacokinetic analysis of plasma concentration vs time was used to determine changes in body fluid compartments. The pathophysiologic effects of endotoxin were monitored by clinical evaluation, blood chemical changes, and blood gas determinations. All horses became dyspneic with...
Halnan CR.The prognostic use of karyotyping in equine breeding has been recommended since 1976. Specimens used and laboratory methods are described. The system of karyotype evaluation is explained together with a glossary of terms. The principal aberrations in horses are defined. The present state of knowledge in cytogenetics in horses is reviewed dealing with infertility in the mare, where sex chromosomes give clear indication of problems; the situation with respect to anomalies found in stallions and hermaphroditism is explained coupled with recent concepts of chromosomal roles in reproduction. The fu...
de Oliveira AC, Rosenbruch M, Schulz LC.The morphology of asteroid bodies in equine arteries is demonstrated by light microscopy as well as by scanning and transmission electron microscopy combined with chemical analysis. Asteroid bodies first occur in horses at four weeks of age in all investigated tissues except the esophagus and always are located in the subendothelial space. The number, shape, ultrastructure and chemical composition of asteroid bodies differ markedly--depending on the age of the horse. Asteroid bodies are round and smooth in foals, but are shaped irregularly and have several projections and marked stratified cal...
Sohrabi Haghdoost I, Zakarian B.THE results of a 20 year retrospective study of the tumours diagnosed in all equine cases referred to the Faculty of Veterinary Medicine, University of Teheran, for surgical treatment or post mortem examination are reported here.
Lloyd KC, Harrison I, Tulleners E.A single injection of reserpine in an adult horse was believed to induce toxicosis for several days. Clinical signs included erratic, colic-like behavior followed by depression, bradycardia, miosis, ptosis, and paraphimosis. Diarrhea was not observed and may have been due to the effect of xylazine given with the reserpine. The horse was supported with IV fluids and intensive nursing care. Gradual improvement was noted 72 hours after the horse received the drug. Qualitative analysis via high-performance liquid chromatography was positive for reserpine. Methamphetamine is the recommended antidot...
Prescott JF.A proposal for the development of Canadian veterinary education and of the organization of the profession is described. There should be one veterinary school with four branches (the current colleges). A student would train at any college in comparative medicine for two and one-half years and then train for 12 months or more in a specialty taught at one or more colleges. These specialties are general veterinary practice, poultry practice, public health and regulatory medicine, ruminant practice, swine practice, equine practice, small animal practice, fish medicine, fur-bearing and exotic animal...
Courtney CH, Asquith RL.ALTHOUGH the seasonal transmission of equine cyathostomes is well documented in cool climates (Ogbourne 1978),
less is known about their transmission in warm climates.
Australian studies have suggested that these parasites do not
survive well during the long, hot summers of the humid
subtropics (English 1979a.b). Development of egg to third
stage larva (L3) was rapid during the summer but the
percentage of larvae that survived to ascend herbage was very
low. In contrast, larvae survived for longer periods during the
cooler months and the highest L3 populations were observed
during spr...
Pedersoli WM, Fazeli MH, Haddad NS, Ravis WR, Carson RL.Endometrial tissue and blood serum gentamicin (GT) concentrations were determined in 6 ovariectomized pony mares given intrauterine infusions (50 ml of a 5% commercial aqueous solution of GT) each day for 5 consecutive days. The mares were subjected to the following 3 treatments: (1) GT infusion only (trial A, control); (2) progesterone plus GT (trial B, P + G); and (3) estradiol plus GT (trial C, E + G). Endometrial tissue concentrations of GT (micrograms/g) at 24 and 120 hours were significantly higher (P less than 0.05) in trials B (65.54 +/- 15.57 and 100.33 +/- 19.27) and C (73.33 +/- 22....
Brockschmidt LD, Loch WE, Sikes JD.An experiment was conducted to test the effect of repeated transcervical (non-surgical) uterine flushing and a prostaglandin analogue (PG) on the estrous cycle of pony mares. Uteri in group A were trancervically flushed for embryos 7 to 9 days post ovulation. In addition, group B mares were given 5 ml of PG by intramuscular injection on the day of flushing. Group C served as controls and were not flushed or given PG but were allowed to cycle normally. All mares (except controls) were bred A.I. every other day during estrus. There was no effect on embryo recovery rate from repeated flushing or ...
Snow DH, Harris RC, Gash SP.Four thoroughbred horses performed 4 gallops (G1-G4) with intervals of 5 min. With one exception, gallops were sustained at maximal speed over 620 m. Muscle biopsy samples of the middle gluteal and brachiocephalicus were taken before, during, and after exercise and assayed for ATP and intermediary metabolites. The results showed a major involvement of the brachiocephalicus, in addition to the middle gluteal, during galloping. In three horses, who were clearly fatigued, muscle ATP decreased by up to 50% by the end of G4. This was matched by an equal rise in inosine 5'-monophosphate. Pronounced ...
Chan CW, Collins EA.An angiosarcoma involving the right frontal and maxillary sinuses in a nine-year-old Thoroughbred mare was studied post mortem by light and electron microscopy. Important diagnostic features included malignant endothelial cells lining ill-defined vascular spaces, supported by other vasoformative elements. Rhabdomyoblasts were also found. The tumour is apparently rarely seen in the nasal passages of the horse.
Miller PJ, Holmes JR.Observations on seven cases of mitral insufficiency are described. Three of the horses had recent histories of cardiac failure and formed a separate group in which there were marked haemodynamic changes which varied in relation to heart rate but were associated with pulmonary hypertension, elevated right ventricular pressure and low peak left ventricular pressure. In the other four horses the heart appeared to be compensating at rest but to be unable to cope with severe exertion. On auscultation, a widespread pansystolic murmur and a prominent third heart sound were characteristic of the left ...
Duncan ID, Brook D.Four two-year-old Thoroughbreds suffered an acute gastrointestinal illness shortly after dosing with mineral oil which was thought to have been contaminated with an organophosphate compound. Three weeks later all four were noted to be dyspnoeic and endoscopic examination showed that they had developed bilateral laryngeal paralysis. Two of the horses died during severe bouts of dyspnoea six and eight months later and the third was killed shortly thereafter. Examination of the left and right recurrent laryngeal nerves from these horses showed a severe loss of myelinated fibres distally, especial...
Sønnichsen HV, Hansen SF.Osteochondrosis is a rapidly growing problem in the horse population and reports are frequent. Osteochondritis dissecans can in most cases be treated surgically, but reports on results are lacking. This paper reports the results of surgery of the tibiotarsal joint in 43 cases.
Dunsmore JD.An attempt was made to control or eliminate Strongylus vulgaris from a closed group of three horses at pasture near Perth, Western Australia, by dosing with ivermectin on four occasions during the time of year when it was believed that environmental conditions would eliminate all the non-parasitic stages of that species. At necropsy, five months after the last dose of anthelmintic and after continually grazing the same pastures, no S vulgaris or arterial lesions were found in those horses and S edentatus, Draschia megastoma and Habronema species were also almost completely eliminated.
Goulden BE, Anderson LJ, Cahill JI.An endoscopic survey was performed to assess arytenoid cartilage movement during quiet respiration in 48 Clydesdale horses. Physical characteristics which could influence the length of the recurrent laryngeal nerves were also recorded from these horses and the relationship of these characteristics to the presence of abnormal left arytenoid cartilage movements was assessed statistically. Some degree of abnormal arytenoid movement was observed in 50% of the animals over one year of age. No significant correlation between sex, age, estimated weight, height, or neck length could be found although ...
Dunsmore JD, Jue Sue LP.A survey was conducted on the prevalence of the major gastrointestinal parasites in 140 horses necropsied in Perth, Western Australia, during 1979 to 1982. Adult Strongylus vulgaris were found in 22.5 per cent of horses and verminous arteritis in 62.9 per cent. The peak worm prevalence was in November to January (summer). S edentatus had a similar prevalence and seasonality but S equinus was not found in this survey. Draschia megastoma and Habronema muscae were found in 66.2 per cent and 35.3 per cent of horses respectively. Infection is probably acquired in summer when 8 per cent of the Musca...
Issel CJ, Adams WV, Foil LD.Progeny of a band of horses, positive by the agar-gel immunodiffusion (AGID) test for equine infectious anemia (EIA) antibody, were observed through their weaning over a 4-year period. Sentinels (AGID test-negative) were allowed to mingle with EIA-infected mares and their foals in pasture situations in an area with high populations of potential vectors. Of 27 adult sentinels, 8 (30%) seroconverted in annual rates ranging from 0% to 75%. In contrast, only 2 of 31 (6%) foals weaned became infected. Difference in infection rates between adult sentinels and foals was significant (chi 2, P less tha...
Zurkowski M, Kuryl J.A new genetic variant in the horse Pi system, designated Z2, was reported in Polish Arabs by using two-dimensional agarose polyacrylamide gel electrophoresis. The frequencies of Pi alleles F, G, L, L2, N, S, U, W, Z and Z2 were found to be 0.036, 0.005, 0.171, 0.013, 0.008, 0.237, 0.416, 0.003, 0.107 and 0.004 respectively.
Thurston CC, Stefanovski D, MacKinnon MC, Chapman HS, Richardson DW, Levine DG.The objective of this study was to determine the diagnostic ability of serum amyloid A (SAA) and fibrinogen for early detection of surgical site infection (SSI) after equine internal fixation. Horses undergoing internal fixation for fracture, arthrodesis, or osteotomy with internal fixation for limb deformity were included in the study. SAA and fibrinogen were measured on blood samples preoperatively and on days 1, 3, 5, 7, 10, and 14 postoperatively. Statistical analysis included use of Spearman's rank correlation, logistic regression, and calculating the area under the receiver operating cha...
Park CA, Hines HC, Threlfall WR.Equine lymphocyte antigen (ELA) gene frequencies were estimated for pacing and trotting Standardbred mares residing on a breeding farm in central Ohio. The ELA gene frequencies for Ohio Standardbreds did not differ significantly from the ELA gene frequencies of Kentucky Standardbreds, determined by Bailey (1983). No significant differences were found in the distribution of ELA class I antigens in horses with lower overall fertility or a history of abortion on the investigated breeding farm. Likewise, no significant association was observed when the ELA types of both the mare and the stallion t...
Flisińska-Bojanowska A, Gill J, Komosa M.1. The diurnal changes in the levels of lactic (LA) and pyruvic (PA) acids and in values of pH, pO2 and pCO2 were studied in the blood of barren and later on in pregnant and lactating mares, throughout three subsequent years. 2. Blood samples were taken every 4 hr, for one day, each month, throughout 3 years. 3. The mares were kept and fed in the same conditions, lighting was natural. 4. In barren mares, diurnal rhythm in LA, PA, pO2 and pCO2 was found. 5. The pregnancy as well as lactation masked diurnal rhythms in parameters studied, except the LA level during lactation but then the acrophas...
Capolongo F, Gallina G, Fidani M, Baia F, Montesissa C.This study investigated whether a single intra-articular administration (IA) of dexamethasone (DEX) in horses at therapeutic dosage could exert a systemic effect by influencing the hypothalamic-pituitary-adrenal axis activity as a consequence of (limited) absorption and systemic distribution. The results indicated that DEX was detectable in urine collected 12-48 h after IA administration and that injection was accompanied by a reduced urine excretion of cortisol, 6β-hydroxycortisol (6βOHF) and two other metabolites of cortisol lasting up to 48 h post-DEX administration. The systemic effect...
Midon M, Yamada DI, Zangirolami Filho D, Simionato GC, Feringer Junior WH, Conde G, Hofmeister EH.This study evaluated the agreement between invasive blood pressure (IBP) values measured in three different arteries and by an oscillometric device (NIBP) with the ones from the transverse facial artery (FA). Six horses (424.2 ± 40.7 kg) were sedated with xylazine (0.6 mg/kg IV), induced with ketamine (2 mg/kg IV) and midazolam (0.1 mg/kg IV), and maintained with isoflurane (1.2 MAC) for 90 minutes in lateral recumbency. FA, auricular artery (AA), lateral digital artery (LDA), and metatarsal artery (MA) were catheterized, and a standard adult cuff was placed on the tail. IBP and NIBP values w...
Inoue Y, Asai Y, Tomita M, Kuribara K, Kobayashi M, Kaneko M, Toba Y.In laboratory animals, man and cell culture experiments, milk basic protein was reported to suppress bone resorption and promote bone formation. However, no studies in horses have previously examined the effect of milk basic protein. Objective: To evaluate the effect of milk basic protein supplementation on bone metabolism in young Thoroughbred horses in training. Methods: Twenty 2-year-old horses in training were used for 90 days in this study. The treatment group was fed a basal diet with 1 g of milk basic protein and the control group a basal diet only. Blood samples were collected on Days ...
Do Carmo GM, Da Silva AS, Klauck V, Pazinato R, Moura AB, Duarte T, Duarte MM, Bochi GV, Moresco RN, Stefani LM.Toxoplasmosis is an important parasitic disease affecting several species of mammals, but little is known about this disease in horses. This study aimed to investigate the levels of several immunological variables and markers of cell damage in the serum of seropositive horses for Toxoplasma gondii. Sera samples of adult horses from the Santa Catarina State, Brazil used on a previous study were divided into groups according to their antibody levels for T. gondii determined by immunofluorescence assay, i.e. 20 samples from seronegative horses (Group A - control), 20 samples from horses with tite...
Salvadori MC, Rieser EM, Ribeiro Neto LM, Nascimento ES.The seeds of Guaraná are rich in xanthines and are used for the preparation of guaraná powder which is very commonly given to horses as a 'tonic' in Brazil. In this paper, the xanthine content of guaraná powder was determined, in addition to its clearance time in horses. Thin-layer chromatography was used as a screening procedure and high-performance liquid chromatography was performed to quantify the drugs in both the powder and urine samples. The guaraná powder was found to contain 2.16, 1.10 and 36.78 mg g-1 of theobromine (TB), theophylline (TP) and caffeine (CF), respectively, and in ...
Menzies RA, Lewis JR, Reiter AM, Lundström TS.Equine dentistry should no longer be thought of as art over science. To be an effective equine dental clinician requires considerable investment in knowledge beyond the basic veterinary degree. It requires current scientific dental knowledge and adherence to the fundamental principles of medicine, dentistry, and surgery. Knowledge and principles will provide clinicians with the necessary information to make more evidence-based decisions as the scientific literature continues to evolve. Diagnosis and therapy should be seen as journeys with a destination, keeping in mind the values of the Hippoc...
Darby S, Sanchez LC, Mallicote MF, House AM, Plummer CE, Nadruz V, Benmoha RH, Roberts SM, Derendorf H, Silva-Sanchez C, Claire J, MacKay RJ.Creeping indigo (Indigofera spicata) toxicosis is an emerging problem among horses in Florida and bordering states. Objective: To quantify the putative toxins l-indospicine (IND) and 3-nitropropionic acid (NPA) in creeping indigo collected from multiple sites and to measure plasma toxin concentrations in ponies fed creeping indigo and horses with presumptive creeping indigo toxicosis. Methods: Experimental descriptive study with descriptive observational field investigation. Methods: Air-dried creeping indigo was assayed for IND and NPA content. Five ponies were fed chopped creeping indigo con...
Tjalsma EJ, van Maurik JM.There are few descriptions of an abnormal white line in the horse, and it is not known what causes this disorder. Thirty horses and ponies with this disorder were examined mycologically, as were 30 horses and ponies with normal hooves. Scopulariopsis brevicaulis was detected in 60% of the animals with an abnormal white line with or without hollow wall or brittle toe.
Sloet van Oldruitenborgh-Oosterbaan MM.A Dutch Warmblood yearling stallion was referred for skin lesions, oedema and diarrhoea. At rectal palpation a cecocolonic intussusception was diagnosed, that might have been present for at least one week. A short literature review of cecocolonic intussusception is given.
Dias IR, Maia LM, Quaresma M, Cotovio M, Silva FC.Complete fractures of the third metacarpal/metatarsal bones (Mc/t3) are not common, but can occur in various situations and all types of horses, contributing for approximately one third of all long bone fractures in the horse, mostly related to external trauma or to high energy injuries. To stabilize Mc/t3 fractures in the horse, conservative management with walking casts and/or open reduction and internal fixation techniques are referred in the scientific literature, these last one generally by double platting application to bone surface in 90 degrees. In the present case will be described a ...
Platt H.From a perinatal survey carried out on Thoroughbred studs, information was obtained on the incidence, mortality and long-term effects of joint-ill and other bacterial infections. Many of these infections occurred in foals with a history of other perinatal abnormalities, and in foals in which receipt of colostrum was delayed. There was no direct relationship between the incidence of infection and maternal age, but prenatal lactation and loss of colostrum were more frequent in older mares. There was a significant reduction in the incidence of infections in foals given neomycin and framomycin dur...
Baxter GM, Humphries GB.A large abscess in the lateral neck region of a horse was treated with percutaneous drainage. The abscess was localized with ultrasonography and aspirated by use of a 7.7-cm spinal needle. A stainless-steel guide wire was passed through the needle, and tissue dilators were used to enlarge the percutaneous hole. A multiperforated polyvinylchloride catheter that was placed within the abscess cavity permitted aspiration and lavage of the abscess. The abscess resolved over the next 10 days with no complications. Percutaneous abscess drainage is commonly performed in people and may have application...
Cesar FB, Stewart AJ, Boothe DM, Ravis WR, Duran SH, Wooldridge AA.Nine horses received 20 mg/kg of intravenous (LEV ); 30 mg/kg of intragastric, crushed immediate release (LEV ); and 30 mg/kg of intragastric, crushed extended release (LEV ) levetiracetam, in a three-way randomized crossover design. Crushed tablets were dissolved in water and administered by nasogastric tube. Serum samples were collected over 48 hr, and levetiracetam concentrations were determined by immunoassay. Mean ± SD peak concentrations for LEV and LEV were 50.72 ± 10.60 and 53.58 ± 15.94 μg/ml, respectively. The y-intercept for IV administration was 64.54 ± 24.99 μg...