Veterinary medicine for horses encompasses the study and application of medical practices to diagnose, treat, and prevent diseases in equine species. This field involves a comprehensive understanding of equine anatomy, physiology, pathology, and pharmacology. Veterinary practitioners employ a range of diagnostic tools and therapeutic interventions to address health issues in horses, including lameness, gastrointestinal disorders, respiratory conditions, and infectious diseases. Preventative care, such as vaccination and deworming programs, is also a significant aspect of equine veterinary medicine. This page gathers peer-reviewed research studies and scholarly articles that explore various aspects of veterinary medicine as it pertains to horses, including advancements in diagnostic techniques, treatment protocols, and preventive health strategies.
Purohit RC, Mysinger PW, Redding RW.A continuous series of electroencephalograms (EEG) was obtained from each of 6 mature horses which had been given xylazine and ketamine hydrochloride IV. Electrocardiograms and respiratory rates were also obtained. The EEG of the unsedated standing adult horse displayed a dominant fast activity in the range of 25-35 Hz, 5-30 microV superimposed over slower 1-4 Hz, 10-50 microV activity with occasional 10-14 Hz, 10-40 microV spindle-type activity. The xylazine-sedated horse displayed hypersynchronous EEG patterns, with the dominant activity being 1-3 Hz, 10-70 microV with overlying mixed freque...
Simpson CF, Buergelt CD.The alveoli of the lungs of 2 aborted foals contained elongated, dense bodies when examined histologically and by transmission and scanning electron microscopy. By light microscopy, the bodies (10 to 40 micrometers in size) stained intensely with the Gram stain, and up to 10 were present within an alveolus. Electron microscopy determined that such bodies were not cellular in origin but appeared to be a congealed fluid product composed of layers of fibrillar-like material. From the human literature, it was concluded that these intraalveolar bodies were probably congealed amniotic fluid.
Gunn HM.A modification of the histochemical reaction to demonstrate myosin adenosine triphosphatase activity in skeletal (striated) muscle was used to define the density of capillaries in transverse sections of 3 muscles (semitendinosus, diaphragm, and pectoralis transversus) of horses and dogs. Thoroughbred horses and Greyhound dogs, breeds noted for their speed in running, were compared with other members of their respective species. Thoroughbred cross horses were grouped with non-Thoroughbreds for comparison with Thoroughbreds. The area of muscle supplied by a capillary was remarkably similar in mu...
Joyner LP, Donnelly J, Huck RA.The results of complement fixation (CF) test for equine piroplasmosis on sera from horses destined for international movement from Great Britain and Ireland are presented and analysed. No horses born and continuously resident in the British Isles were found carrying CF antibodies to either Babesia equi or B caballi. Positive animals were found to have association with the following countries where known tick vectors occur: Spain, Portugal, Belgium, France, Poland, USSR and Arabian Gulf countries. Data on the persistence of CF antibodies in animals subjected to repeated testing showed that some...
Stover SM, Brown MP, Kelly RH, Farver TB, Knight HD.Six adult mares were given a single dose of aqueous suspension procaine penicillin G (300,000 IU/ml) IM at a dosage of 22,000 IU/kg of body weight (15.4 mg of penicillin G/kg). Serum, synovial fluid, peritoneal fluid, and urine penicillin concentrations were measured serially over a 48-hour period. The mean peak serum penicillin concentration was 1.42 microgram/ml at 3 hours. Penicillin was detected in synovial fluid and peritoneal fluid, which obtained mean peak penicillin concentrations of 0.62 microgram/ml and 0.58 microgram/ml, at 4 hours and 3 hours, respectively. These concentrations ste...
Dunn HO, Smiley D, Duncan JR, McEntee K.The karyotypes of a Welsh pony and a Standardbred were 64,XX/64,XY and 63,XO/64,XY respectively. Both intersexes were true hermaphrodites with bilateral ovotestes. Neither intersex showed stallion-like behaviour. Each one had an underdeveloped penis, bilateral seminal vesicles and uterine tissue. It would appear that the chimerism in these equine intersexes resulted from double fertilization or fusion of blastocysts. Mosaicism in the Standardbred is a possibility, resulting from loss of a Y chromosome by anaphase lag in an early embryonic XY cell.
Carakostas MC, Moore WE, Smith JE.Intravascular granulocyte kinetics in 4 healthy horses were determined with chromium-51 as the cell label. The disappearance rate of labeled granulocytes was an exponential function. Mean total blood granulocyte pool (+/- 1 SD) was 5.65 +/- 1.514 X 10(8) granulocytes/kg of body weight, of which 2.71 +/- 0.715 X 10(8) granulocytes/kg were circulating and 2.94 +/- 0.876 X 10(8) granulocytes/kg were marginated along blood vessel walls. The mean disappearance half-life (T1/2) was 10.5 +/- 1.33 hours and the mean granulocyte turnover rate was 8.84 +/- 1.495 X 10(8) granulocytes/kg/day. A granulokin...
McCullagh KG, Silver IA.The historical development of "firing" as a treatment for various complaints in animals and man is followed from the first surviving written account by Vegetius (approximately AD 500) to the present day. Changing concepts as to the mechanism of action of the actual cautery are examined in relation to physiological understanding at various times and conflicting views and evident fallacies are discussed. It is of particular interest that firing of "sinewes" (tendons and ligaments) was expressly forbidden until the 18th century. It is concluded that "firing" is an outmoded practice for which ther...
McGuire TC, Perryman LE, Banks KL.Following the descriptions of immunodeficiencies in horses beginning in 1973, there has been considerable effort to develop methods for differential diagnosis and to determine the cause and prevalence of the disorders. In addition, the equine immunodeficiencies, especially combined immunodeficiency, have been studied from a comparative viewpoint with the goal of finding information applicable to similar diseases of children. Coincident with the development of knowledge about the immunodeficiencies per se, considerable information about several aspects of immunology has been obtained. It is the...
Noonan NE.Adult female dogs or pony mares were subjected to a nonlethal dose of CCl4 (0.5 ml/kg of body weight). Amounts of several plasma enzymes thought to be indicative of hepatic disease were monitored. Plasma enzymes alanine aminotransferase, aspartate aminotransferase (AST), alkaline phosphatase (ALP), arginase, gamma-glutamyltransferase (GGT), and iditol dehydrogenase (ID), as well as total plasma bilirubin, were determined in these animals before and after the administration of the CCl4. In the dog, GGT was not significantly increased, whereas ALP values were increased during days 1 to 6. In the...
Rowlands IW.The world-wide foaling rate in the mare is low and in the Hannoverian breed has remained asymptotic at about 50 per cent for over 150 years. In an attempt to discover some of the possible reasons for this low fertility rate, the evolutionary history of the perissodactyls, the odd-toed ungulates, is reviewed here. Of the 156 genera of this order, 152 are in the fossil record; this gives them the highest extermination rate of all the mammal groups. Some of the unusual and unique features of the reproductive physiology of the mare and their possible association with low fertility are considered.
Moore JN, Garner HE, Shapland JE, Hatfield DG.Bacterial endotoxin injected intravenously into conscious ponies produced alterations in cardiopulmonary and gastrointestinal function. Specifically, tachypnoea, dyspnoea, hypoxaemia, colic, lactic acidosis and diarrhoea resulted from administration of 10 micrograms/kg Escherichia coli endotoxin. Pretreatment of the ponies with a potent prostaglandin synthetase inhibitor, flunixin meglumine, prevented these ill effects of endotoxin.
Mackay RJ, Iverson WO, Merritt AM.A 4-year-old stallion was examined because of a 2-month history of inappetance and weight loss. Diarrhoea had also developed a month before presentation. Abnormal clinical findings were emaciation, diarrhoea, ventral oedema, palpable mesenteric lymph node enlargement and a large mass in the left cranial portion of the abdomen. Significant laboratory findings were anaemia (packed cell volume 0.21 litres/litre), hypoalbuminaemia (16 g/litre) and xylose malabsorption. The horse was euthanased and at necropsy a 10.5 kg pendunculated mass composed of granulation tissue was found within and attached...
Allen BV.A technique for automating equine differential leucocyte counts by analysis of volume distribution curves using the Coulter Channelyzer has been developed and evaluated. A comparison between the results obtained by this method and standard microscopic techniques showed good agreement in most cases. Blood samples can be analysed for both differential and total leucocyte counts at a rate of 25/h. For each sample an average 16,000 leucocytes are classified by the Channelyzer. The method of volume analysis is suitable for the precise counting of polymorphonuclear neutrophils, lymphocytes and eosin...
Carakostas MC, Moore WE, Smith JE, Johnson D.The functional capacity of the marrow granulocyte reserve (MGR) in 4 adult horses was studied, using 51Cr-labeled leukocytes. The mean increase in the peripheral granulocyte count following injections of etiocholanolone (0.3 mg/kg) was 870 granulocytes/mm3, and the mean increase following prednisolone administration (200 mg) was 5,880 granulocytes/mm3. Etiocholanolone failed to mobilize the MGR and decreased the rate of granulocyte egress from the blood. Prednisolone rapidly mobilized the MGR and markedly decreased the granulocyte specific activity during the first 3 hours after injection.
Mottironi VD, Perryman LE, Pollara B, Mickey MR, Swift R, McGrath P.Combined immunodeficiency disease (CID) is a genetic disorder of T and B lymphocyte production which results in a nonfunctional immune system. It is inherited as an autosomal recessive trait and has been reported in humans and in horses of the Arabian breed. Arabian horses known to have the CID gene and horses of unknown carrier status were tested using a microlymphocytotoxicity technique. Computer chi 2 analysis distinguished six serologically defined specificities. The study of unrelated horses and a limited number of families showed that the specificities behave as codominant alleles segreg...
Dixon KE, Kreider JL.Fifty ejaculates, ten from each of 5 mature stallions, were utilized to study the effects of calcium and fatty acids on equine spermatozoa which were isolated in 3% Bovine Serum Albumin (BSA). The ejaculates were evaluated for percent motile spermatozoa, rate of forward movement, debris, primary abnormalities and secondary abnormalities. The isolation procedure consisted of layering 2 ml of diluted semen (100 x 10(6) spermatozoa/ml) over 6 ml of 3% BSA in 13 x 125 mm columns in a water bath (37 degrees C). After 30 min., the top semen layer and upper half of the BSA layer were withdrawn from a...
Levina V, Timms M, Vine J, Steel R.A synthetic Interleukin-1 receptor antagonist peptide with the sequence Acetyl-Phe-Glu-Trp-Thr-Pro-Gly-Tyr-Trp-Gln-Pro-Tyr-Ala-Leu-Pro-Leu-OH has been identified in a vial seized during a stable inspection. The use of peptide-based Interleukin-1 receptor antagonists as anti-inflammatory agents has not been previously reported, making this peptide the first in a new class of sports doping peptides. The peptide has been characterized by high-resolution mass spectrometry and a detection method developed based on solid-phase extraction and liquid chromatography - triple quadrupole mass spectrometr...
Melly V, Ortved KF, Manzi TJ, Richardson DW, Stefanovski D, Wulster KB.Increasing accessibility and advancements in computed tomographic (CT) imaging improve understanding of the contributors to poor performance in the Thoroughbred racehorse. Objective: To characterise an unreported site of tarsal subchondral bone injury (SBI) in Thoroughbred racehorses. Methods: Retrospective, cross-sectional analytical study. Methods: Tarsal CT scans of 108 horses were reviewed for evidence of SBI in the dorsodistolateral calcaneus (DDLC). Signalment, including age, breed, sex, and discipline of horses, was recorded. The association of DDLC SBI with Thoroughbred racehorse compa...
Manohar M, Goetz TE, Nganwa D.Diaphragmatic O2 and lactate extraction were examined in seven healthy ponies during maximal exercise (ME) carried out without, as well as with, inspiratory resistive breathing. Arterial and diaphragmatic venous blood were sampled simultaneously at rest and at 30-s intervals during the 4 min of ME. Experiments were carried out before and after left laryngeal hemiplegia (LH) was produced. During ME, normal ponies exhibited hypocapnia, hemoconcentration, and a decrease in arterial PO2 (PaO2) with insignificant change in O2 saturation. In LH ponies, PaO2 and O2 saturation decreased well below tha...
Sirois J, Betteridge KJ, Brault A.Embryo transfer was used in an equestrian teaching center in order to produce as many foals as possible from their preferred mares during a single breeding season. Embryo collection by uterine lavage was attempted in five donor mares on 25 occasions 6.5 days after ovulation. Sixteen of the collection attempts (64%) yielded a total of 17 blastocysts. Of these 17 embryos, 13 were immediately transferred transcervically into recipient mares that had ovulated within two days of the time of ovulation in the donors, three were frozen for later transfer, and one was lost. Eight of the freshly transfe...
Díaz-Espiñeira M, Escolar E, Bellanato J, Rodriguez M.The secondary constituents accompanying calcite and vaterite (crystalline forms of calcium carbonate) in the sabulous deposits from 140 vesical samples and one renal sample of equine urine were studied by infrared spectroscopy (IR), scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). Apatitic calcium phosphate, present in 12 per cent of the samples, generally appeared in the form of spherulites with smooth and rough surfaces. Calcium sulphate, clearly detected by IR in 12.7 per cent of the samples, did not have a characteristic structure under SEM, although EDX detec...
Bartels JE, Beckett SD, Brown BG.Serial arteriography was used to determine the vascular pattern and blood flow in the penis of the pony stallion. Ponies were anesthetized with pentobarbital sodium, and catheters were surgically introduced into the internal pudendal and obturator arteries. The vascular anatomy was visualized by angiography via image-intensified fluoroscopy and was recorded on 70-mm film at 3 frames/s or by direct radiography. Blood flow into the corpus cavernosum penis (CCP) was limited during quiescence because the blood was immediately shunted into the venous system. After vasodilation with mild stimulation...
Castro LA, Brown MP, Gronwall R, Houston AE, Miles N.Six foals from 6 to 8 weeks of age were given a single oral dose of rifampin at a dosage of 10 mg/kg of body weight. Serum rifampin concentrations were measured serially during a 24-hour period. The mean peak serum rifampin concentration was 6.7 micrograms/ml at 4 hours after treatment. The concentration decreased slowly, and at 24 hours the mean value was 2.7 micrograms/ml. The elimination half-life was 17.5 hours, and the elimination rate constant was 0.04/hr.
Puschner B, Galey FD.Poisoning in the horse can present a highly complex case. The practitioner, owner, toxicologist, and pathologist play important roles, and all contribute information that may be important to the case. Once all the information is available, all the evidence is collected (historical, clinical, pathologic, and analytic), and proper sampling of specimens has occurred, a complete summary of the findings can be provided to the client. Based on identification of a potential toxic source and, ultimately, the diagnosis, specific treatment of affected animals and prevention of additional cases can be in...
Pedersoli WM, Ravis WR, Belmonte AA, McCullers RM.Digoxin (elixir, 0.022 mg/kg) was administered via stomach tube to healthy horses of mixed breeding and sexes. Serum digoxin concentrations reached a peak (2.21 +/- 0.6 ng/ml) at approximately 1 hour after dosing and had a half-life of 28.8 +/- 10.7 hours. Digoxin kinetics followed a triexponential curve, indicating that at least a 2 compartmental model is required to characterize the serum concentration-time curve after this route of administration. It was calculated that to achieve average serum concentrations of 1.1 ng/ml, an oral dose of 17.4 microgram of digoxin elixir/kg/day and an IV do...
Mizobe M, Kondo F, Toyoshima C, Kumamoto K, Terada T, Nasu H.A rapid method was developed to analyze delta-bilirubin (B delta), diconjugated bilirubin (DCB), monoconjugated bilirubin (MCB), and unconjugated bilirubin (Bu) by direct injection of sera using high-performance liquid chromatography (HPLC) with an internal-surface reversed-phase silica support (ISRP) column. Sharp bilirubin peaks were obtained using a simple mobile phase of acetonitrile: 0.5 M Tris-HCl buffer (20:80, v/v, pH 7.2). A variable-wavelength detector set at 450 nm, 0.01 absorbance unit full scale (AUFS), and a recorder set at 4 mm/min were used for detection. Peaks for B delta, DCB...
Koterba AM, Drummond WH.Provision of adequate nutritional support to the sick neonatal foal is a vital part of intensive care; frequently, however, it is very difficult to accomplish. In this article, current recommendations concerning both enteral and parenteral nutrition are discussed.
Takeda A, Tanaka H, Shinohara T, Ohtake I.A sample preparation method for mass chromatographic detection of doping drugs from horse plasma is described. Bond Elut Certify (1 g/6 ml) is used for the extraction of 4 ml of horse plasma. Fractionation is performed with 6 ml of CHCl3-Me2CO (8:2) and 5 ml of 1% TEA-MeOH according to its property. Simple and effective clean-up based on non-aqueous partitioning is adopted to remove co-eluted contaminants in both acid and basic fractions. Two kinds of 1-(N,N-diisopropylamino)-n-alkanes are co-injected with the sample into the GC-MS system for the calculation of the retention index. Total recov...
Corda M, Pellegrini M, Rinaldi A.Diamine oxidase was prepared from horse kidney by a procedure involving heat denaturation at 50 degrees C, ammonium sulfate fractionation, chromatography on hydroxyapatite and on G-200 Sephadex columns. This procedure gave about 1000 fold purification over the crude kidney cortex homogenate. The enzyme preparations thus obtained are stable only at high ionic strength. The effect on enzyme activity of salt concentration and various stabilizing agents have been investigated. The horse kidney diamine oxidase is irreversibly inhibited by carbonyl reagents and shows substrate specificity quite simi...