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.
Ahmed H, Chatterjee BP, Kelm S, Schauer R.A sialic acid-specific lectin, scorpin, has been purified to apparent homogeneity from the Indian scorpion Heterometrus granulomanus by affinity chromatography on equine submandibular gland glycopeptides linked to Sepharose and gel filtration on Sephadex G-200. The lectin has a molecular mass of 500 000 Da and was dissociated into single polypeptide chains of 15 000 Da, as determined by SDS gel electrophoresis in the presence of 2-mercaptoethanol. Scorpin is a glycoprotein containing 2.8% sugars. Its specificity was investigated by the inhibition of hemagglutination with various derivatives of...
Wagstaff KH, Dickson SL, Bailey A.The history of WEE surveillance in Utah is reviewed, beginning with the 1933 outbreak involving 3,958 horses. The step by step formation of the Utah Mosquito Abatement Associations surveillance program from 1957 to the present is discussed. Results of an enlarged sentinel chicken flock surveillance program in Utah during 1983 (3 sero-conversions in September), 1984 and 1985 (no sero-conversion) show the lack of WEE activity in the surveillance area.
Manohar M.Systemic distribution of blood flow was studied in 11 healthy adult grade ponies, using radionuclide-labeled microspheres (15 micron diameter) that were injected into the left ventricle. Measurements were made at rest, during severe exercise (SE) without furosemide, as well as during SE at 10 minutes and 120 minutes after furosemide administration (1.0 mg/kg, IV). During SE, heart rate, cardiac output, mean aortic pressure, and whole body O2 consumption were 220 +/- 4 beats/min, 720 +/- 44 ml/min/kg, 169 +/- 4 mm of Hg, and 126 +/- 9 ml of O2/min/kg, respectively. With SE performed after furos...
Garza F, Thompson DL, St George RL, French DD.In Exp. 1, 16 long-term ovariectomized pony mares were used to determine the effects of treatment with estradiol benzoate (EB) and dihydrotestosterone (DHT) benzoate alone, and in combination, on secretion of follicle stimulating hormone (FSH) and luteinizing hormone (LH) in daily blood samples and after three consecutive injections of gonadotropin releasing hormone (GnRH). Administration of EB alone, or in combination with DHT, every other day for 11 d reduced (P less than .05) concentrations of FSH and increased (P less than .05) concentrations of LH in daily blood samples, and increased (P ...
Denkhaus M, Van Amstel S.Non-commercial, endotoxin positive, intravenous fluids as well as a commercially available intravenous fluid were given to clinically normal horses. Endotoxin-positive fluids caused clinical signs attributable to endotoxaemia. Leukopenia, preceded by a fluctuating white cell count, was observed in horses showing clinical signs. The commercial intravenous fluid had no effect on the white cell count or on the clinical state. Precautions to be taken and recommendations are made with regard to the monitoring of horses in which one might be forced to use non-commercial intravenous fluids.
Calisher CH, Mahmud MI, el-Kafrawi AO, Emerson JK, Muth DJ.Paired sera from 28 nonvaccinated horses with serologically confirmed western equine encephalitis (WEE) virus infections were evaluated for immunoglobulin (Ig)M and IgG directed against WEE virus, by use of enzyme immunoassay. Twenty-one of the horses developed greater than or equal to 4-fold increases or decreases in serum IgM titers in paired serum samples, confirming the diagnosis of WEE in these horses. Of the remaining 7 horses, 1 had stable IgM titers, 1 had a 2-fold increase in IgM titer between paired sera, 2 had 2-fold decreases in IgM titer, and for 3 horses adequate volumes were not...
Husebekk A, Husby G, Sletten K, Marhaug G, Nordstoga K.Amyloid was extracted from the liver of a horse that had developed amyloidosis after being used for several years for the production of antibodies to bacterial antigens. The amyloid fibrils were shown to be of the AA type. Two AA proteins with molecular weights of 9000 and 11,000 and with identical partial N-terminal amino acid sequences were identified. Marked structural homology with AA from other species including man was seen, although clear species-related antigenic specificity was observed. SAA isolated from an acute phase (septic abortion) horse serum was identical to AA with respect to...
Winder NC, von Fellenberg R.Pulmonary parenchymal tissues from 6 healthy horses and from 9 horses with chronic bronchiolitis were evaluated by use of an indirect immunofluorescent technique. In horses of both groups, the diffuse interstitial immunofluorescence was most intense for immunoglobulin (Ig)G, moderate for IgA, and minimal for IgM. Intensity of fluorescence was increased markedly in diseased lungs exposed to anti-IgA and anti-IgG. Around small bronchi and large bronchioles of healthy horses, IgA-containing cells generally were more numerous than were IgG-Fc fragment (Fc)-containing cells; in small bronchioles, h...
Dubey JP, Miller S.A 10-year-old pony died 5 days after the onset of a nervous disorder. Necropsy revealed a yellowish area of discoloration (1.5 by 1 cm) in the medulla oblongata. Microscopically, necrosis and nonsuppurative myeloencephalitis were found in the medulla oblongata. Immature and mature meronts (25 by 10 microns) were seen in neural tissue and in capillaries of the brain stem. Organisms were similar structurally to those seen in equine protozoal myeloencephalitis of horses.
Bell LG, Lowe JE.A questionnaire was designed to determine the incidence of major injuries, severe colic, and acute laminitis in horses at American Horse Shows Association (AHSA) A- and B-rated shows, ie, those shows requiring a veterinarian in attendance. The questionnaire was sent to the show stewards and filled out by the attending veterinarians of the AHSA A- and B-rated shows held from January 1982 to October 1984. Of 2,952 questionnaires sent out, 799 (27%) were completed and returned by veterinarians; 99 of them were discarded because of incomplete or misleading information. The study revealed a low inc...
Smith JE, DeBowes RM, Cipriano JE.Corticosteroid preparation was administered to 7 Shetland Ponies and 10 Quarter Horses. Serum iron concentration increased dramatically for 48 to 72 hours after the steroid treatment, whereas serum iron-binding capacity and serum ferritin concentration did not. An increase in available iron may allow bacteria to proliferate when ponies or horses are stressed or treated inappropriately with corticosteroids.
Pearson EG, Hedstrom OR, Sonn R, Wedam J.A 4-day-old foal died with bloody diarrhea. Using a mouse neutralization test, Clostridium perfringens type C was isolated from intestinal contents, and alpha and beta toxins were identified. About 4 m of the jejunum had severe necrohemorrhagic enteritis. Microscopically, large, rod-shaped, gram-positive bacteria were seen on necrotic intestinal villi by use of Brown and Hopp's stains.
Seibert BP, Newcomb KM, Michael BF.Critical tests were done on 24 naturally parasitized horses to compare the antiparasitic activity of an oral paste preparation of mebendazole and trichlorfon with that of the marketed powder formulation. Each formulation was administered at the recommended dosages of 8.8 mg of mebendazole and 40 mg of trichlorfon/kg of body weight. Efficacy of the paste formulation ranged from 97.7% to 100% against 2nd- and 3rd-stage Gasterophilus spp, adult Strongylus vulgaris, S edentatus, Parascaris equorum, small strongyles; and larval and adult forms of Oxyuris equi. Adverse effects were generally limited...
Wernette KM, Hubbell JA, Muir WW, Sams RA.The cardiopulmonary effects of 3 dosages of doxapram hydrochloride (0.275 mg/kg, 0.55 mg/kg, and 1.1 mg/kg, IV) were studied in 6 adult horses. Doxapram given IV significantly (P less than 0.05) decreased PaCO2 and increased respiratory rate, cardiac output arterial blood pressures (systolic, mean, and diastolic) arterial pH, and PaO2 at 1 minute after each dose was administered. Heart rate and mean and diastolic pulmonary arterial blood pressure were significantly (P less than 0.05) increased 1 minute after the 2 larger dosages of doxapram were given (0.55 mg/kg and 1.1 mg/kg, IV), but not af...
The Journal of traumaJune 1, 1986
Volume 26, Issue 6 559-560 doi: 10.1097/00005373-198606000-00013
Busch HM, Cogbill TH, Landercasper J, Landercasper BO.During the past 6 years 134 patients were admitted as the result of bovine (cow) and equine (horse) trauma. The mechanism of injury was fall from horse in 45 patients, animal assault in 42, animal kick in 39, and animal-drawn vehicle accident in eight. Injury Severity Score (ISS) ranged from 1 to 41 and was greater than or equal to 25 in 11 patients. One hundred seventeen operative procedures were performed by ten groups of surgical subspecialists. Mortality was nil. Ideal management of these injuries includes treatment in a regional trauma center and an educational program of preventive measu...
Kohn CW, Strasser SL.Urine samples were obtained from 6 healthy mares. During a 2-day acclimation period, mares were kept in stalls, fed sweet feed and mixed grass hay, and allowed free access to water and trace mineral salt. The mares were crosstied in their stalls within reach of hay, salt, and water for 24 hours during which urine was obtained by constant flow via indwelling Foley catheters. Twenty-four-hour urine production was 7,649 to 11,904 ml/day (mean = 9,212 +/- 1,9285) or 14.7 to 25.1 mlĝ/day. (mean = 19.3 +/- 4.1). Urinary excretion and clearance of electrolytes and protein were determined from aliquo...
Manohar M.Regional distribution of brain blood flow (radionuclide labelled 15 microns diameter microspheres) and O2 supply were studied in 11 healthy adult grade ponies at rest and during severe exercise (SE) performed on a treadmill (heart rate = 220 +/- 4 beats X min-1; VO2 = 126 +/- 9 ml X min-1 X kg-1). During SE, the mean aortic pressure increased to 169 +/- 4 mm Hg and the pHa, PaCO2 and PaO2 were 7.213 +/- 0.010, 30 +/- 1 mm Hg and 85 +/- 4 mm Hg, respectively. The hemoglobin concentration increased by 59.6% with SE. Whereas blood flow increased in the cerebellar gray matter (96%), pons (39.5%) a...
Lyons ET, Drudge JH, Tolliver SC.The efficacy of 2 injectable formulations of ivermectin, administered intraorally at the dosage of 200 micrograms/kg of body weight, was evaluated against naturally occurring infections by abomasal nematodes in lambs in 2 controlled tests. One test (A) included 17 lambs treated with the equine formulation and 16 nontreated lambs. For the other test (B), 14 lambs were treated with the bovine formulation, and 12 were nontreated. In controlled test A, only mature nematodes were recovered, and removals were 98% to 100% for Haemonchus contortus, Ostertagia circumcincta male, O trifurcata male, Oste...
Lees P, Taylor JB, Higgins AJ, Sharma SC.The clinically recommended dose rate of phenylbutazone (4.4 mg/kg) was administered intravenously as a single dose to five Welsh Mountain ponies. Distribution of phenylbutazone and its active metabolite oxyphenbutazone into body fluids was studied by measuring concentrations in plasma, tissue-cage fluid, peritoneal fluid and acute inflammatory exudate harvested from a polyester sponge model of inflammation. The ready penetration of phenylbutazone into inflammatory exudate was demonstrated by the relatively high mean value for Cmax of 12.4 micrograms/ml occurring at a time of 4.6 h and a mean A...
Gabal MA, Awad YL, Morcos MB, Barakat AM, Malik G.Mycotoxicoses involving horses, rabbits and cattle have been studied. Fusarium tricinctum and T-2 toxin were isolated from all incriminated feedstuffs. Other isolated trichothecenes from the feed included HT-2, verrucarins and roridin. The toxins were separated, identified and quantitated using thin-layer chromatography, gas-liquid chromatography and mass spectrometry. T-2 toxin was detected in amounts varying from 0.5-204 ppm. The contaminated feedstuffs in connection with the affected horses and rabbits, included cereal grains (corn, cornstalks, bran and barley), whereas fescue hay was assoc...
Dubey JP, Porterfield ML.Multifocal areas of necrosis and infiltrations of mononuclear cells were seen in lung specimens of an equine fetus aborted 2 months before term. Extracellular and intracellular protozoa were seen in the alveolar tissue. Individual organisms were 4 microns by 2.5 microns, and cyst-like structures were 25 microns by 18 microns. Organisms did not stain with periodic acid-Schiff or by use of the immunoperoxidase and peroxidase-antiperoxidase method for Toxoplasma gondii. Twelve days after abortion, the mare had serum antibody titer of less than 1:10 against T gondii.
Murray RC, Gaughan EM, Debowes RM, Huston LC, Cooper VL, Welsh T.A 4-month Arabian filly presented for abdominal pain of 30 hours duration was found to have tachycardia, tachypnea, congested mucous membranes and gross abdominal distension. Further examination disclosed gastric reflux and small intestinal distension. Dehydration, prerenal azotemia, electrolyte abnormalities and metabolic alkalemia were observed. There was a progressive nonresponse to analgesic medication and deterioration in the foal's physiologic condition consistent with a small intestinal strangulating obstruction. Surgical exploration was declined. Necropsy examination revealed incarcera...
Treupel E, Czerwonka N, Schröder S, Böhm J, Wehrend A.Retained fetal membranes in mares is a relative frequent disease which can lead to severe complications. Two case studies are described in which mares died acutely despite intensive care. Pathological examination confirmed severe hemorrhage as the cause of death in both animals.
Nara PL, Krakowka S, Powers TE, Garg RC.Fourteen young outbred horses, divided into 2 groups on the basis of 18- or 24-hour skin-test reactions to Streptococcus equi, were inoculated nasopharyngeally with virulent S equi. Animals (n = 6, group I) with evidence of previous exposure to S equi (positive dermal response and existing serum antibodies), with one exception, developed minimal or no signs of disease after inoculation. In contrast, S equi skin-test negative and seronegative horses (n = 8, group II) developed predictable and severe clinical signs of infection after their inoculation, including shedding of the organism from nas...
Ignácio FS, Montechiesi DF, Bergfelt DR, Orlandi CMB, Carvalho LR, Puoli Filho NJ, Meira C.The present study was designed to evaluate luteinization rates subsequent to aspiration of dominant follicles (≥25 mm) in the absence of a functional CL (progesterone <1 ng/mL) and characterize the temporal changes in plasma concentrations of progesterone following aspiration-induced luteinization during the estrous cycle in mares. A total of 29 estrous cycles involving 15 mares in a cross-over design were randomly assigned to five groups: 1) ASP-F≥25 mm (n = 6; follicle aspiration 25-29 mm), 2) ASP-F≥30 mm (n = 6; follicle aspiration 30-34 mm), 3) ASP-F≥35 mm (n = 6; foll...
Bailey JE, Pablo L, Hubbell JA.A 7-month-old Quarter Horse filly was admitted for surgical repair of a right olecranon fracture. Anesthesia was achieved with xylazine hydrochloride, guaifenesin, ketamine hydrochloride, and halothane. Two and a half hours after induction of anesthesia, myotonia, muscle fasciculations, and sweating, concurrent with high serum potassium concentration and associated electrocardiographic changes consistent with hyperkalemic periodic paralysis, were observed. Treatment included intermittent positive-pressure ventilation, changing intravenous administration of fluids from lactated Ringer's solutio...
Ensink JM, Barneveld A, Klein WR, van Miert AS, Vulto AG.The plasma disposition of ampicillin after intravenous administration at a dose rate of 15 mg/kg was studied in six healthy, 1-month-old foals. The oral bioavailability of pivampicillin was determined in the same foals at four ages, ranging from 11 days to 4 months. Pivampicillin was administered orally at a dose rate of 19.9 mg/kg, which is equivalent on a molecular basis to 15 mg/kg ampicillin. Ampicillin concentrations in plasma were determined up to 12 hours after administration. After intravenous administration, the mean distribution and elimination half-lives of ampicillin were 0.121 and...
Dupont S, De Spiegeleer A, Liu DJ, Lefère L, van Doorn DA, Hesta M.Commercial immunoglobulin E (IgE)-based tests are available for diagnosis of food allergies and are commonly used in equine practice. However, these tests have been proven unreliable as a screening method in man and other species, but not critically evaluated in equids. Therefore, a commercially available IgE-based test for horses was evaluated. Objective: To evaluate the consistency of the results obtained with a commercially available IgE-based test for food allergy diagnosis in ponies (Phase I) and to subject ponies to a provocation trial with the presumed allergens (Phase II). Methods: All...
Loch W, Worthy K, Ireland F.Sixteen non-pregnant pony mares were divided into four groups of similar age and bodyweight (bwt). Groups were randomly assigned to one of four treatments consisting of oral administration of perphenazine (0.5 and 1.0 mg/kg bwt, phenothiazine (10 mg/kg bwt) and a control group. Blood samples were taken by jugular venepuncture and plasma prolactin concentrations measured using an homologous assay for equine prolactin. Analysis of variance was conducted on data designed as a split plot over time. Perphenazine given orally (0.5 and 1.0 mg/kg bwt) increased plasma prolactin concentrations when mea...
Golland LC, Evans DL, McGowan CM, Hodgson DR, Rose RJ.Red blood cell hypervolaemia has been used for diagnosis of overtraining in racehorses, and has been suggested as a mechanism of this cause of loss of racing performance. The effects of overload training (OLT) on the plasma, blood and red cell volumes were investigated in a prospective study in 12 Standardbred horses. Measurements of blood volumes were made after eight and 32 weeks of an exercise training study. Horses were randomly allocated to OLT and control groups (n=6) after 16 weeks of training. Training duration and intensity were increased more rapidly for the OLT group from week 16, u...
al-Afaleq AI, Abu Elzein EM, Hassanein MM.The present epidemiological status of African horse sickness in Saudi Arabia, as shown by seroconversion, virus isolation and clinical observation of sentinel horses is described. No African horse sickness virus activity was detected throughout the duration of the study (from November 1992 to March 1995). These findings support previous reports that African horse sickness is not endemic in Saudi Arabia.
Monzón CM.A direct agglutination test is described to diagnose 'Mal de Caderas' caused by Trypanosoma evansi. The antigen used was a suspension of trypsin-treated parasites stabilized with formalin. The test was evaluated in horses with both natural and experimental infections. Test sensitivity and specificity were 94 and 97%, respectively. Treatment of serum with 2-mercaptoethanol before testing permitted the differentiation of IgM and IgG antibodies, and possible differentiation of current infection from past exposure to the parasite. The antigen was stable over a 6-month evaluation period and also sh...
Huhtinen M, Lagneaux D, Koskinen E, Palmer E.Seventy-five embryos were collected 6 days after ovulation. Sixty embryos were frozen in straws using glycerol as the cryoprotectant in an automatic freezer. In Experiment 1 the freezing and thawing media were supplemented with 1.3 g/l PVP; in Experiment 2 the supplement was 5% FCS. The embryos were thawed for 30 s at +37 degrees C in a waterbath. In Experiment 1 glycerol was removed from 10 embryos in 6 steps. In 10 other embryos, glycerol and sucrose were both removed from the medium in 6 steps. After glycerol and sucrose removal, the embryos were stained with 4',6'-diamidino-2-phenylindole ...
Elzer EJ, Bramlage LR.Outcomes have been reported for a limited number of short frontal plane fractures of the proximal phalanx following nonsurgical treatment and internal fixation. Objective: To describe a new approach, arthroscopic debridement, of short frontal plane fractures of the proximal phalanx in flat-racing Thoroughbreds and post-operative racing outcome. Methods: Retrospective case-control study. Methods: Medical records of 81 Thoroughbred racehorses treated with arthroscopic debridement for frontal plane fractures of the proximal phalanx were reviewed. Diagnostic images and operative reports were used ...
Bidwell LA.Equine anesthesia is complicated regardless of the procedure being performed. Anesthesia for the mare experiencing dystocia is complicated by the size of the fetus, positioning of the mare for the procedure, and concern over drug effect on the fetus through the neonatal period. Anesthesia of the neonate is complicated by multiple factors, specifically, sensitivity to the drugs administered. Ventilatory support, minimizing drugs administered, and minimizing anesthesia time are essential for a positive outcome.