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.
Sweeting MP, Houpt CE, Houpt KA.Eight pairs of pony mares were observed. Members of a pair were housed in adjacent stalls and fed hay ad libitum. The behavior of both ponies was recorded simultaneously in the morning (1000 to 1200 h) and afternoon (1400 to 1600 h) for a total of 117 h. The time budget was: 70.1 +/- 8.6% eating; 17.8 +/- 7.4% standing (including stand rest, stand alert and stand nonalert); 5.2 +/- 7.0% pushing hay; 2.9 +/- 1.2% walking; 1.9 +/- 2.9% drinking; 1.3 +/- 1.1% self-grooming; .2 +/- .3% defecating; .06 +/- .1% chewing nonfood items; .06 +/- .03% urination; .06 +/- .1% licking salt; .07 +/- .1% pawi...
Line SW, Hart BL, Sanders L.Males horses castrated prepubertally occasionally display stallion-like sexual and aggressive behavior as adults. A retrospective survey of 140 horse owners was undertaken to compare the effectiveness of prepubertal versus postpubertal castration on objectionable sexual and aggressive behavior. Of 94 geldings that had been castrated prepubertally (before 2 years of age), 20% to 30% displayed stallion-like sexual behavior and aggression toward horses, and 5% were aggressive toward people in a stallion-like manner. This occurrence of problem behavior was not significantly different from the occu...
Sams RA, Ruoff WW.The pharmacokinetics and bioavailability of cefazolin given (IV, IM) to horses at the dosage of 11 mg/kg were investigated. The disposition of cefazolin given by IV route was characterized by a rapid disposition phase with a half-life of 5 to 10 minutes and a subsequent slower elimination phase with a half-life of 35 to 46 minutes. The total plasma clearance of cefazolin averaged 5.51 ml/min/kg and was due mainly to renal clearance (5.39 ml/min/kg) of unchanged drug. The volume of distribution at steady-state averaged 188 ml/kg. Plasma protein binding of cefazolin at a concentration of 10 micr...
Bowling AT.Accuracy of assigning foal paternity to the second serving stallion for foals whose dams had been bred to two stallions within an interval of 1 to 45 days was investigated using breeding dates from 108 equine paternity cases solved by blood typing. One hundred two of the foals were sired by the second stallion but six foals (5.5%) were excluded as being by the second sires. Thus, breeding dates are not reliable as a sole source of information to assign equine paternity accurately.
Uehara N, Sawazaki H, Mochizuki K.The area of the largest transverse section and the number of muscle fibres in a unit sectional area (1 mm2) were examined in 8 trunk and 12 extremity muscles of young and adult 16 light horses and 8 ponies. It was found that the area of the largest transverse section was enlarged and the number of muscle fibres in a unit area was decreased, with the advance in age. This result suggests that the development of muscle volume does not depend on the increase in the number of fibres, but depends on the hypertrophy of each muscle fibre.
Sexton PE, Bristol FM.Bacteriology, histology, and scanning electron microscopy were used to evaluate uterine involution in 27 mares treated with daily injections of 150 mg of progesterone and 10 mg of estradiol-17 beta, commencing within 18 hours of parturition. These findings were compared with those for 24 untreated mares at postpartum day 10 or 11. The treatment resulted in significantly (P less than 0.05) greater uterine gland proliferation. Gland density was significantly (P less than 0.05) greater in mares treated for 6 to 10 days than in those treated 2 to 5 days. The proportion of ciliated cells to secreto...
Derksen FJ, Robinson NE, Armstrong PJ, Stick JA, Slocombe RF.We measured lung function and airway reactivity to histamine administered by aerosol in two groups of ponies. Principal ponies had a history of heaves, a disease characterized by recurrent airway obstruction when ponies are housed in a barn and fed hay; control ponies had no history of airway obstruction. Ponies were paired (principal and control) and measurements were made when principal ponies were at pasture and in clinical remission (period A), following barn housing when principal ponies had acute airway obstruction (period B), and after a further 1 and 2 wk at pasture (periods C and D). ...
Adams SB, Steckel R, Blevins W.Diskospondylitis was diagnosed in 5 horses admitted to the Purdue University Large Animal Clinic during a 3-year period. Each horse had evidence of cervical pain. Clinical signs and radiography were useful for identifying the diskospondylitis. Cerebrospinal fluid was normal.
Trent AM, Krook L.Bilateral degenerative coxofemoral joint disease and noninflammatory osteonecrosis in the femoral heads were diagnosed in a 5-month-old Standardbred colt. Cytologic evaluation and bacterial cultures of coxofemoral synovial fluid, and radiographic and pathologic examination of the coxofemoral joints were conducted. The cause was not determined; however, a thrombus found in association with 1 focus of osteonecrosis was suspected as an etiologic factor.
Burrows GE, MacAllister CG, Beckstrom DA, Nick JT.The plasma concentrations and pharmacokinetics of rifampin disposition were determined after a single IV, IM, or oral dose of 10 mg/kg of body weight and an oral dose of 25 mg/kg. The overall elimination rate constants per minute were similar for the 10 mg/kg dose (0.0021 +/- 0.0004, IV; 0.0017 +/- 0.0002, IM; and 0.0023 +/- 0.0006, orally). The apparent bioavailability was moderate to low for IM and oral administrations (59.8% +/- 3.2% and 39.5% +/- 5.0%, respectively). The rate of absorption was most rapid for oral administration with an absorption half-life of 249.7 +/- 71.6 minutes as comp...
Colbern GT, Aanes WA, Stashak TS.The case records of 47 mares with third-degree perineal lacerations or rectovestibular fistulae were examined to evaluate their fertility following surgical repair. Of 32 mares bred, 24 became pregnant, suggesting that surgical repair is indicated in any mare with sufficient genetic potential. Perineal trauma after surgical repair was recorded in 3 of 20 mares at subsequent parturition.
Judson DG, Dixon JB.Tritiated thymidine uptake in response to Concanavalin A was recorded as stimulated counts per minute (SCPM) in equine whole blood cultured with an optimum concentration of 3 X 10(4) mononuclear cells/culture. A significant negative correlation was found between log10 SCPM and granulocyte level in culture, in a group of 27 adult horses (r = -0.745, P less than 0.001). Addition of isolated autologous granulocytes to such cultures resulted in a reduction of log10 SCPM of a magnitude similar to that predicted by the gradient of the log10 SCPM/granulocyte level regression line in the group of adul...
Sloet van Oldruitenborgh-Oosterbaan MM, van den Ingh TS.A trotter stallion showing symptoms of emaciation was suspected of disease of the liver associated with cholestasis in view of clinical symptoms (poor appetite, sluggishness, jaundice and oedema) and the results of examination of the blood (increased concentrations of gamma-glutamyl, transpeptidase, sorbitol dehydrogenase, alkaline phosphatase, aspartate aminotransferase and markedly increased conjugated bilirubin). A specimen removed at biopsy of the liver revealed the presence of portal fibrosis and severe cholestasis. At autopsy, it was found that very extensive fibrosis of the pancreas (pr...
Mayr A.Prophylactic immunization of animals against obligat and nonobligat pathogenic zoonoses benefit human health in many ways both directly and indirectly. Typical examples of a direct protective effect are the vaccinations of dogs, cats and foxes against rabies as well as the vaccinations against respiratory diseases in cows, horses, dogs and cats to which the most varied species of pathogens of noncompulsory zoonoses contribute. A considerable contribution to the protection of human health is made by the vaccination against salmonellosis and leptospirosis, against vesicular stomatitis, American ...
Science (New York, N.Y.)February 1, 1985
Volume 227, Issue 4686 522-524 doi: 10.1126/science.3880925
Holland CJ, Ristic M, Cole AI, Johnson P, Baker G, Goetz T.Potomac horse fever, a disease characterized by fever, anorexia, leukopenia, and occasional diarrhea, is fatal in approximately 30 percent of affected animals. The seasonal occurrence of the disease (June to October) and evidence of antibodies to the rickettsia Ehrlichia sennetsu in the serum of convalescing horses suggested that a related rickettsia might be the causative agent. Such an agent was isolated in cultured blood monocytes from an experimentally infected pony. This intracytoplasmic organism was adapted to growth in primary cultures of canine blood monocytes. A healthy pony inoculate...
Sullins KE, Stashak TS, Mero KN.In 6 horses, 2 types of ischemic lesions were created in small intestinal segments by selective ligation of vessels and intestinal wall for 1, 2, or 3 hours. After confirming the ischemia by IV injection of sodium fluorescein, the ligatures were released. Five minutes later, the fluorescent patterns were documented photographically. Observed patterns ranged from normal (identical to that observed in unaffected bowel) to a patchy distribution of non-fluorescence (indicating incomplete perfusion). None of the experimental segments was normal when reevaluated 1 month later. The typical appearance...
Reubsaet FA, Langeveld JP, Veerkamp JH.A spectrophotometric assay was applied for quantitation of sulfated glycosaminoglycans in digested renal basement membranes of six mammalian species. The conditions of digestion and the accuracy of the assay were evaluated. Papain digestion and alkaline treatment appeared to be most effective for solubilization. Basement membrane preparations obtained by sonication contained more glycosaminoglycans than those isolated by detergent treatment. Glomerular basement membranes had generally a higher glycosaminoglycan content than tubular basement membranes.
Rossdale PD, Hopes R, Digby NJ, offord K.An epidemiological study of wastage among racehorses was conducted in 1982 and 1983 among six stables, five of which were in Newmarket. The basis of the survey was the inability of horses to take part in cantering exercise as a result of injury or disease. The greatest number of days lost to training was caused by lameness (67.6 per cent) and respiratory problems (20.5 per cent). Conditions of the foot (19 pe cent), muscle (18 per cent), carpus (14 per cent), fetlock joints (14 per cent), tendons (10 per cent) and sore shins (9 per cent) were the major reasons for training days being lost in 1...
Drumev D.Stated is the use of promising therapeutic formulae that produce prophylactic, metaphylactic, and curative effects at lower input of labour and handling, inciting lower unrest with animals, belonging chiefly to the type of the so-called 'therapeutic systems'. Particular attention is paid to drugs for programmed, continuous, and checkable release of the active ingredients in compliance with what is needed at the time (sustained release forms)-type OROS (oral osmotic system), type 'liquid reservoir', type 'glass cylinders', tablets and boluses of higher relative weight, or multilayer and mosaic ...
Ford EJ, Simmons HA.The production of propionate in the caecum of the horse has been measured in two Shetland-type ponies fitted with caecal and colonic cannulas and fed on hay or on hay and wheat bran. A continuous intracaecal infusion of 14C-labelled sodium propionate was used and samples were obtained from a cannula at the origin of the right ventral colon. A simultaneous intravenous infusion of [2-3H]glucose was used to measure total glucose entry. On a hay diet which provided 177 kJ/kg body-weight per d, mean caecal propionate production was 19.6 (range 17.2-21.2) mg/h per kg body-weight and on a hay and whe...
Tschudi P.The cardiac arrhythmias, classified in disturbances of impulse formation and conduction disturbances, their genesis and clinical significance are described and illustrated with electrocardiograms, registered with the bipolar chest leads.
Grabner A, Kraft W, Essich G, Hänichen T.Cases of enzootic calcinosis in breeding mares in a Southwest German highland area are reported. The symptoms increased in the latter part of summer and existed in disturbances of movement, moderate kyphosis, sensitivity to palpation in the flexor tendons and, especially, the suspensory ligament, weight loss in spite of good food intake during summer-time and painful costal percussion; less clinical signs of renal and cardiac disorders were established. The sickness was caused by a high percentage of Trisetum flavescens in the feeding plants.
Sobiraj A, Bostedt H.This review article deals with a critical comparison between the direct clinical diagnosis for the pregnancy of the mare (rectal and in some cases also vaginal exploration) and indirect methods. Both methods are discussed whether they can be seen as a mutual completion or are suitable for their own. The indirect methods for the pregnancy diagnosis include the hormone-analytic tests as progesterone concentration in serum or milk, the biological and immunological measurements for PMSG in the serum, finally the biological and chemical methods for estrogen contents in the urine of the mare. Furthe...
Gill J, Kompanowska-Jezierska E, Jakubow K, Kott A, Szumska D.In 34 pure-breed Arabian horses divided into four groups (Gr. I, ten pregnant mares; Gr. II, seven barren mares; Gr. III, ten foals born in 1981; Gr. IV, seven foals born in 1982) seasonal changes in the white blood cell system, cortisol level and lyzozyme activity were studied. Seasonal periodicity was found in all groups for the number of lymphocytes, segmented neutrophils and eosinophils and cortisol level. Leukocyte periodicity was found in three groups, but not in the barren mares. In lyzozyme activity there was periodicity in three groups but not in the youngest foals. In the stab neutro...
Ungemach FR.Doping in performance horses is defined as the "illegal application of any substance, except normal diet, that might modify the natural and present capacities of the horse at the time of the race." The prohibition of doping is mainly based on the protection of animals. Doping can be performed with various aims: "doping to win" can be regarded as the classical method by mobilization of overphysiological capacities. Such positive doping may be classified as an acute form using psychomotoric stimulants, as a chronic form using anabolic hormones, and as a paradoxical form using small doses of neur...
Benoit E, Garnier F, Courtot D, Delatour P.Antiserum has been raised in rabbits treated with a 19 nor testosterone-hemisuccinate-bovine-serum-albumin conjugate and used for the development of a specific RIA of plasma 19 nor testosterone. Plasma samples are drawn from testicular and jugular veins of stallions during castration under general anesthesia. Results demonstrate a testicular secretion of 19 nor testosterone and a stress inhibition of this secretion correlatively with stress inhibition of testosterone secretion.
Delacalle J, Burba DJ, Tetens J, Moore RM.To report an neodymium:yttrium-aluminum garnet (Nd:YAG) laser-assisted modified Forssell's surgical technique and outcome for treatment of cribbing (crib-biting) in horses. Methods: Retrospective clinical study. Methods: Ten adult horses with stereotypic cribbing behavior. Methods: Data were obtained from medical records and telephone conversations with owners, trainers, and veterinarians. Surgical technique involved an approximately 34-cm ventral median skin incision starting rostral to the larynx and extending caudally. A 10-cm section of the ventral branch of the spinal accessory nerve was ...
Kósa CA, Nagy K, Szenci O, Baska-Vincze B, Andrásofszky E, Szép R, Keresztesi Á, Mircean M, Taulescu M, Kutasi O.A severe form of recurrent exertional rhabdomyolysis occurs enzootically in a well-defined region of Transylvania, Harghita county. At the highest lying two settlements (more than 800 m above sea level), the prevalence of equine rhabdomyolysis is between 17 and 23%, while in the neighbouring villages in the valley it is less than 2%. The objective of our study was to clarify the role of selenium and vitamin E in the high prevalence of rhabdomyolysis in that region. Soil and hay samples were collected from each area to evaluate mineral content. Ten horses from the non-affected and 20 horses fro...
Mattioli M, Galeati G, Seren E.Prostaglandin F-2 alpha (PGF-2 alpha) receptors of bovine and equine corpora lutea (C.L.) were studied. From both the equilibrium binding data and the dissociation kinetics behaviour, two affinity classes of receptors are evident in the mare, with apparent dissociation constants (Kd) of 1,5 x 10(-9) M and 3.5 x 10(-8) M. Bovine PGF-2 alpha receptors present a homogeneous population of binding sites with Kd = 1 x 10(-8) M. Both bovine and equine C.L. receptors bind PGF-2 alpha in a specific manner; only 13, 14-dihydro-PGF-2 alpha considerably cross-reacts with these receptors. Since in the mare...
Roberts SJ, Myhre G.Equine twinning, related abortion and progestogen plasma concentrations during the gestation period were reviewed. The supplemental administration of exogenous progesterone apparently prevented impending twin abortions in three mares after midgestation. A single viable twin and a mummified fetus were delivered at term by the mares.
Ginther OJ, Rodriguez MB, Beg MA.The temporal relationship of several hormones to a metabolite of prostaglandin F2α (PGFM) was studied in mares and heifers from the beginning of the first PGFM pulse during luteolysis to the end of the second pulse. Mares (n=7) were selected with a 9-h interval between the peaks of the two pulses. In mares, estradiol-17β (estradiol) increased (P<0.05) within each PGFM pulse and plateaued for a mean of 6h between the pulses, resulting in a stepwise estradiol increase. Progesterone decreased linearly (P<0.0001) throughout the intra-pulse and inter-pulse intervals of PGFM. In heifers (n=6...
Van Heerden J, Dauth J, Dreyer MJ, Nichas E, Marshall C, De Waal DT.Selected haematological, blood chemical and serological variables were investigated in healthy Thoroughbreds (n = 45) in training. Haemoglobin concentration, haematocrit, red, white and differential cell counts as well as serum concentrations of total and ionized calcium, sodium, potassium, chloride, urea, creatinine, total protein, albumin, inorganic phosphorus, total bilirubin, iron, glucose, magnesium, alkaline phosphatase, gamma-glutamyltransferase, lactate dehydrogenase, aspartate transaminase, alanine transaminase and creatine kinase were found to be within ranges previously reported for...
Vaughn DM, Smyth GB.The serotonin metabolite, 5-hydroxyindoleacetic acid (5-HIAA) and the dopamine metabolite, homovanillic acid (HVA) in the cerebrospinal fluid (CSF) of seven clinically normal horses were evaluated with reverse phase high pressure liquid chromatography and electrochemical detection. Comparisons of the neurotransmitter metabolite concentrations were made on CSF collected simultaneously from the atlanto-occipital and lumbosacral regions. There were significantly higher amounts of 5-HIAA and HVA in atlanto-occipital CSF than in lumbosacral CSF. Mean 5-HIAA concentrations in atlanto-occipital and l...
Mirck MH.In 3,791 horses and ponies submitted to the Department of Internal Disease of Farm Animals of the Faculty of Veterinary Medicine, Utrecht, the faeces were studied for the presence of parasites. The results were classified by age groups and months of arrival. Eggs of the Strongylus type were found to be present in 57.3 per cent of the faecal samples, eggs of Parascaris equorum were present in 6.1 per cent, eggs of Oxyuris equi in 1.2 per cent, eggs or larvae of Dictyocaulus arnfieldi in 0.2 per cent, eggs of Anoplocephala in 2.5 per cent and oocysts of Eimeria leuckarti in 0.3 per cent. Eggs of...
Sato F, Hirota K, Tozaki T, Ito K, Dhakal P, Taya K, Endo Y, Murase H, Nambo Y.A Thoroughbred colt with ambiguous external genitalia was presented for clinical and histological examinations. The colt had a short penis that faced backward between his hind limbs. The measurements of luteinizing hormone, follicle stimulating hormone, testosterone and ir-inhibin showed a tendency to increase gradually from April. Both the sex-determining region of the Y chromosome and amelogenin gene fragments were detected by the PCR method. A cytogenetic analysis revealed the 63,XO/64,XY mosaic karyotype (ratio 83:17). In autopsy, immature symmetrical subcutaneous testes were found in the ...
Becker M.During the last 10 years 268 laparotomies by a midline incision were performed. A high incidence of seromas, fistulas caused by suturing material and wound ruptures were observed. After finding only a small number of publications in the veterinary medicine about wound healing disturbances an analysis of the human medical literature was done. This induced the change of our surgical procedure and suturing technique: The midline incision and surgical management during the laparotomies in 14 horses suffering from colic were performed by a minimized trauma. The abdominal wall was closed layer by la...
Dau SL, Azevedo MDS, Mazaro RD, de La Corte FD, Fighera R.Neurolytic compounds are widely used by equine practitioners for the management of lameness, mostly related to the foot. The present study aimed to evaluate the neurotoxicity of 2% ammonium chloride (2% AC) applied adjacent to the palmar digital nerves in six miniature horses. The 2% AC and 0.9% saline solution were randomly injected into three and one palmar digital nerve of each horse, respectively. Nerve samples were collected by neurectomy performed under general anesthesia at 5, 12, 19, 35, 47, and 62 days after treatment, with one horse per day of surgery. The inflammatory reaction to p...
Shields GE, Whitcomb MB, Vaughan B, Wisner ER.Injuries involving the femoral third trochanter are an uncommon but important source of equine lameness; however, clinical localization can be challenging. The purpose of this retrospective study was to describe ultrasonographic and scintigraphic findings in a group of horses with presumed third trochanter injury. Medical records of an equine referral hospital were searched from 2004-2014, and 20 horses met the inclusion criteria. Lesions consistent with third trochanter fracture were identified with ultrasound in 14/20 horses. Onset of lameness was acute (11), insidious (2), or unknown (1). A...
Bueno AC, Galuppo LD, Taylor KT, Jensen DG, Stover SM.To compare the mechanical shear strengths and stiffnesses obtained from in vitro testing of a simulated complete third carpal bone (C3) frontal plane radial facet slab fracture (osteotomy) stabilized with either a 4/5 Acutrak (AT) compression screw or a 4.5-mm AO cortical bone (AO) screw inserted in lag fashion. Drilling, tapping, and screw insertion torques, forces, and times also were compared between AT and AO implants. Methods: In vitro biomechanical assessment of site preparation, screw insertion, and shear failure test variables of bone screw stabilized simulated C3 slab fracture in pair...
Nelis SA, Sievers C, Jarrett M, Nissen LM, Kirkpatrick CM, Shaw PN.In this paper, a method for the sensitive and reproducible analysis of lignocaine and its four principal metabolites, monoethylxylidide (MEGX), glycylxylidide (GX), 3-hydroxylignocaine (3-HO-LIG), 4-hydroxylignocaine (4-HO-LIG) in equine urine and plasma samples is presented. The method uses liquid chromatography coupled to tandem mass spectrometry operating in electrospray ionisation positive ion mode (+ESI) via multiple reaction monitoring (MRM). Sample preparation involved solid-phase extraction using a mixed-mode phase. The internal standard adopted was lignocaine-d(10). Lignocaine and its...
Brown MP, Stover SM, Kelly RH, Farver TB.Six adult mares were given a single dose of ampicillin trihydrate (250 mg/ml) intramuscularly at a dosage of 20 mg/kg body weight. Serum, synovial fluid, peritoneal fluid and urine ampicillin concentrations were measured serially over a 48 h period. The mean peak serum ampicillin concentration was 2.49 micrograms/ml at 6 h. Ampicillin was found in synovial fluid and peritoneal fluid, which obtained mean peak ampicillin concentrations of 1.65 micrograms/ml and 1.81 micrograms/ml at 6 h and 4 h respectively. These concentrations declined in parallel with serum concentrations and were still detec...
Fitzgerald BP, Mellbye LB.Two experiments were performed to test the hypothesis that the seasonal suppression of gonadotrophin pulse frequency in anoestrous horse mares reflects inhibitory neural mechanisms. In a preliminary experiment (Exp. 1) conducted in February, 4 anoestrous mares were sedated by repeated intravenous injections of xylazine, an alpha 2-adrenergic receptor agonist. On the day of treatment, 1-2 LH pulses were observed in xylazine-treated mares. In contrast, during a 12-h period only 1/8 untreated control mares exhibited a LH pulse. In Exp. 2, the effect of xylazine-induced sedation on pulsatile gonad...
Martin-Rosset W, Andueza D, Vermorel M.The accuracy and precision of the National Research Council (NRC), Gesellschaft für Ernährungsphysiologie (GfE) and Institut National de la Recherche Agronomique (INRA) systems for predicting the digestible energy (DE) value of hays were determined from the results of 15 digestibility trials with natural grassland hays and 9 digestibility trials with lucerne hays that all met strict experimental and a tight corpus of methods. The hays were harvested in the temperate zone. They covered broad ranges of chemical composition and DE value. The INRA system was more accurate than the other two syst...