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.
Kohn CW, Chew DJ.Laboratory evaluation of renal function in horses has advanced dramatically in the last 10 years largely as a result of the interest generated by the creative approach to diagnostic indices taken by Brobst, Traver, Coffman, and others. Some methods of assessing renal function discussed here are clearly outside the scope of a practice environment but are available in referral hospitals for use in difficult or unusual cases. Other methods described, such as calculation of fractional excretions and urine to serum creatinine ratios, are accessible and readily interpreted by the veterinary practiti...
Bayly WM.It is the purpose of this article to review much of the information that is available regarding the adjunctive use of clinicopathologic data in evaluations of performance horses by veterinarians. Wherever possible, distinctions are made between findings that pertain to racehorses and those that apply most specifically to horses involved in "submaximal" events like combined training and endurance races. It is hoped that the material presented will clarify some of the problems associated with the interpretation of this data, and possibly stimulate the dissemination of additional information that...
Sweeney CR, Whitlock RH, Meirs DA, Whitehead SC, Barningham SO.Complications associated with Streptococcus equi infection developed in 15 (20.3%) of 74 horses on one farm included death, guttural pouch empyema, purpura hemorrhagica, upper respiratory tract obstruction, pneumonia, pleuropneumonia, agalactia, mesenteric lymph node abscessation, and periorbital abscessation. Death was attributed to pneumonia in 3 horses and to upper respiratory tract obstruction in 2 horses. One horse was euthanatized because of severe purpura hemorrhagica.
López ML, de Souza W, Bustos-Obregón E.The structure, relative density, and distribution of anionic sites on the surface of epididymal and ejaculated spermatozoa were studied using polycationic ferritin (CF), colloidal iron hydroxide (CIH), various enzymatic treatments, methylation, and de-acetylation. Macro-molecules containing sugar residues, probably sialic acid, are part of the sperm membrane and show a characteristic distribution and density that is dependent of the sperm region and of its origin. Unlike the spermatozoa of other eutheria examined, the exposure of the stallion spermatozoa to neuraminidase treatment did not prod...
Meyers KM, Menard M, Wardrop KJ.This is a review of equine hemostasis and is divided into three sections. The initial portion describes the normal hemostatic system and includes platelet function, coagulation, fibrinolysis and control processes. The second phase is devoted to laboratory tests of hemostasis, and the last section provides information on specific alterations.
Dyer KR, Duncan ID.The intraneural course of nerve fibres in the equine recurrent laryngeal nerve was investigated by partially ligating the nerve at a proximal site, and 3-8 weeks later, tracing the course and spatial relationships of intact and degenerating fibres along the distal stump. This nerve was chosen because of its great length, the fact that it is a nonbranching motor nerve and because of debate about the course of abductor and adductor nerve fibres in the recurrent laryngeal nerve. Six ponies were used and in each the recurrent nerve was partially ligatured about 20 cm from the larynx, using a fine ...
Ravis WR, Duran SH, Pedersoli WM, Schumacher J.The pharmacokinetics of phenobarbital were determined in six mature horses after a single oral dose. Horses were administered a 5.5 mg/kg of body weight oral dose of phenobarbital tablets. Based on the combined evaluation of i.v. and oral results, phenobarbital displayed two-compartment pharmacokinetics in the horse with a terminal half-life of 19.0 +/- 4.4 (mean +/- SD) h. This half-life is considerably shorter than those reported for dogs and humans. The steady-state volume of distribution (Vdss/F) and the total body clearance (Clt/F) of phenobarbital were 0.753 +/- 0.115 l/kg and 27.9 +/- 9...
Wiśniewski E, Kuźma K.The normal level of plasma lysozyme of 9 Tarpane-like horses was 0.922pg/ml. This was
calculated from determinations performed 5 times in a period of 14 months. Observations on the
normal plasma level of lysozyme in the horse revealed marked variations in individual animals, as well
as in the whole group and in the mean values calculated for individual horses. The model for the
subsequent studies was an experimental fever evoked by the administration of E. colz LPS in a dose of
0.1 pg/kg body weight. Blood samples from the jugular vein were taken just before LPS injection, and
then for 8...
Winston S, Fiscus S, Hesterberg L, Matsushita T, Mildbrand M, Porter J, Teramoto Y.The development of three separate rapid ELISAs for detecting antibodies in host serum to three different viruses is described. These include: 1. A direct antigen assay using enzyme labelled anti-canine Ig for detecting antibodies to canine parvovirus, 2. A competitive ELISA using a feline infectious peritonitis virus-specific monoclonal antibody labelled with enzyme, and 3. A competitive ELISA using an equine infectious anemia virus-specific monoclonal antibody and enzyme labelled antigen, p. 26. The utility and benefits of each of the three approaches is emphasized.
Riggs MW.Currently recognized equine immune deficiency disorders include failure of passive colostral immunoglobulin transfer, combined immunodeficiency, selective IgM deficiency, transient hypogammaglobulinemia, and agammaglobulinemia. Additional equine immune deficiency disorders probably exist. Immune deficiency should be suspected in any horse experiencing persistent or recurrent infections that are not responsive to conventional therapy.
Weber JM, Parkhouse WS, Dobson GP, Harman JC, Snow DH, Hochachka PW.Plasma lactate turnover rate of Thoroughbred racehorses was measured by bolus injection of [U-14C]lactate at rest and two levels of submaximal treadmill exercise (3-4 m/s trot, 6% incline, and 6.5 m/s horizontal canter). Our goals were 1) to determine the relative effects of changes in cardiac output and in plasma lactate concentration on turnover rate [using cardiac output data from Weber et al. (28)] and 2) to assess the importance of lactate as a metabolic fuel in a trained animal athlete. Lactate turnover rates were 9.3 mumol.min-1.kg-1 (rest), 75.9 mumol.min-1.kg-1 at the beginning of the...
Stadler P.The anterior enteritis syndrome in the horse is reviewed with reference to the aetiology, pathogenesis, clinical findings, laboratory findings, diagnosis, treatment, prognosis and post mortem findings.
Illera JC, Hamlin RL, Illera M.Bipolar and unipolar limb leads and unipolar thoracic lead ECG were obtained from 100 male crossbred horses. P-wave morphologic features were classified according to positivity negativity and monopolarity dipolarity, and the percentage of horses that had P waves of a given morphologic class in each lead was calculated. P-Wave morphologic features of 4 precordial leads were most uniform, with greater than 80% of the horses having a single configuration.
Engelking LR, Paradis MR.This article addresses clinical problems that present in equine liver disease. It also discusses the variety of laboratory tests available to the clinician that can differentiate the type and degree of liver dysfunction. This is followed by a more specific discussion regarding unique features of equine bilirubin and bile acid metabolism.
Burgess EC, Mattison M.Infection with Borrelia burgdorferi was associated with encephalitis in a horse. The horse lived in an area of Wisconsin endemic for B burgdorferi infection. Borrelia burgdorferi was isolated from the brain, but rabies virus was not detected in the brain. Serum obtained from the horse had a B burgdorferi antibody titer of 1:2,048, but was negative for antibodies to eastern and western encephalomyelitis.
Sugiura T, Matsumura T, Fukunaga Y, Hirasawa K.A sero-epizootiological study was conducted on horses which showed clinical pyrexia at two training centers, each of which maintained 1, 200 to 2, 100 racehorses for training, of the Japan Racing Association. It continued from 1980 to 1985 to clarify the cause of pyrexia, so that measures might be considered for the prevention of infectious disease. A total of 3, 849 horses were found to be affected with pyrexia for the 6 years. Of them, 2, 852 horses were tested to equine herpesvirus type 1 (EHV-1), equine rhinovirus type 1 (ERhV-1), rotavirus and equine adenovirus (EAdV) by collecting paired...
McEntee M.A cutaneous mass (1.5 cm in diameter) was removed from the head of a horse and was diagnosed histologically as eumycotic mycetoma. Immunofluorescence, performed on formalin-fixed, paraffin-embedded tissue, identified Pseudallescheria boydii as the etiologic agent. Findings from earlier reports of eumycotic mycetoma were compared with those of this horse.
Ricketts SW.The clinician may use the clinical pathology laboratory as a valuable aid to diagnosis and management, for the assessment of response to treatment, and in preventive medicine programs. Each "link in the chain," that is, sample selection, collection, handling, analysis, result reporting, and interpretation must be carefully and efficiently managed, using an informed combination of art and science, to provide a useful endpoint. This general introduction precedes more specific and detailed articles.
de Waal DT, van Heerden J, Potgieter FT.Serologically negative horses, as determined with the indirect fluorescent antibody test (IFA), were infected with Babesia equi and 60 days later with Babesia caballi. The only clinical signs of disease observed in these animals were a febrile reaction and slight icterus. Haematological changes included a drop in haematocrit and haemoglobin concentration, as well as lowered platelet counts. The serum concentrations of albumin, iron and phosphorus were lowered. Mildly elevated serum bilirubin and fibrinogen concentrations were observed. Antibody titres were determined with the IFA and complemen...
Pascoe DR, Pascoe RR, Hughes JP, Stabenfeldt GH, Kindahl H.One hundred mares carrying twin conceptuses between gestation days (GD) 12 and 30 were assigned to 4 groups. Group-1 mares (n = 20) were given a placebo (sterile saline solution, IV, and sesame oil, IM). Group-2 mares (n = 32) were given a single dose of progesterone (625 mg, IM) in sesame oil. Group-3 mares (n = 28) were given multiple progesterone treatments (625 mg, IM) at 6-day intervals until GD 42. Group-4 mares (n = 20) were given a single treatment of flunixin meglumine (500 mg, IV) and progesterone (625 mg, IM). Each group was further assigned to equal subgroups A and B according to t...
Craig DR, Pankowski RL, Car BD, Hackett RP, Erb HN.Several surgical alternatives have been described for the management of cecal impaction in the horse, but none has met with consistently successful results. This study was done to evaluate a surgical bypass of the cecum by anastomosis of the ileum to the right ventral colon (ileocolostomy). A ventral midline celiotomy was performed on nine adult ponies (155-350 kg) and a mechanically stapled 10 cm side-to-side ileocolostomy was created. In five ponies a complete cecal bypass (CCB) was created by transecting the ileum distal to the anastomosis. In the other four, an incomplete cecal bypass (ICB...
Ignatchenko AP, Bogomaz VI, Tugaĭ VA, Chuĭko AA.Biospecific sorbents for affinity chromatography of proteolytic enzymes have been synthesized by attaching cyclopeptide antibiotic gramicidin S to organo-silica supports. It is shown possible to attach gramicidin S to the organo-silica supports using glutaric aldehyde, p-benzoquinone, soluble and insoluble carbodiimides. The sorbents prepared by these methods were successfully applied for the purification of the crude pepsin from horse gastric juice and proteolytic complex produced by Acremonium chrysogenum.
Parker JE, Fibini SL, Car BD, Erb HN.An ischemic bowel model was used to stimulate adhesion formation in eight ponies. Heparin (40 USP u/kg) or saline was administered intravenously at surgery and was continued subcutaneously every 12 hours for 48 hours to evaluate the efficacy of heparin in preventing intraabdominal adhesions. Ponies were euthanatized after 6 weeks, and postmortem examinations were performed. A statistically significant difference was found between the heparin-treated and the control groups. Adhesions developed in three of four control ponies, and adhesions did not develop in three of four heparin-treated ponies...
Kuttler KL, Zaugg JL, Gipson CA.The therapeutic efficacies of imidocarb and parvaquone were tested against Babesia equi of European origin in carrier horses and for induced acute infections in splenectomized ponies. Imidocarb, at a dosage of 4 mg/kg of body weight, given IM at 72-hour intervals 4 times, was ineffective in eliminating B equi-carrier infection in 9 mature geldings. A single IM administration of 4 mg/kg was not therapeutic in acutely infected splenectomized ponies. When given at 3 different dosages and treatment schedules, parvaquone was ineffective in clearing carrier infection. Parvaquone given IM once at a d...
Strzemienski PJ, Dyer RM, Kenney RM.Neutrophils isolated from jugular blood of ovariectomized mares were studied for the effect of estradiol and progesterone on bactericidal activity against Staphylococcus aureus. In experiment 1, neutrophils obtained from 4 mares were tested for bactericidal activity by adding estradiol (43 pg/ml) or progesterone (6.4 ng/ml) to the bactericidal assay. In experiment 2, 3 of the 4 ovariectomized mares were given 2 mg of estradiol, IM, daily for 3 days. Eighteen days after the initial estradiol injection, mares were given 300 mg of progesterone, IM, for 6 days. Neutrophils from these mares were te...
Marqués FJ, Higgins S, Chapuis R, Waldner C.Circulating l-lactate concentration is commonly measured in hospitalized horses by sampling from indwelling intravenous (IV) catheters. However, there are no published evidence-based recommendations to prevent contamination by lactated Ringer's solution (LRS). Objective: Withdrawing 10 mL of blood from the LRS-containing extension set connected to the IV catheter before obtaining the sample for analysis should be adequate to obtain accurate measurement of blood lactate concentration (BLC). Methods: Thirty-three adult hospitalized horses receiving constant rate infusion of LRS. Methods: Immedia...
Schoster A, Anderson ME.A 9-year-old Quarter horse was presented for chronic refractory pneumonia. On necropsy, an hepatic abscess, caudal vena cava thrombosis, pulmonary thromboembolism, and embolic pneumonia were identified. Similar lesions have been reported in cattle as caudal vena cava thrombosis syndrome, however this syndrome has not previously been reported in horses. Un cheval Quarter horse âgé de 9 ans est présenté pour une pneumonie réfractaire chronique. À la nécropsie, un abcès hépatique, une thrombose de la veine cave caudale, un thromboembolisme pulmonaire et une pneumonie embolique ont été...
Klei TR.Diagnosis of internal parasitism is based on many factors, including clinical signs, case histories of individual animals and the herds of which they are a part, and, finally, specific laboratory findings. Laboratory methods used can be divided into those associated with the qualitative and quantitative examination of feces for parasite eggs, larvae, and oocysts, and laboratory findings on changes in physiologic status of individuals that may be produced by specific parasites.
Suwannachot P, Joosten BJ, Klarenbeek A, Hofma J, Enzerink E, van Weeren PR, Everts ME.To investigate the effects of moderate short-term training on K+ regulation in plasma and erythrocytes during exercise and on skeletal muscle Na+,K(+)-ATPase concentration in young adult and middle-aged horses. Methods: Four 4- to 6-year-old and four 10- to 16-year-old Dutch Warmblood horses. Methods: The horses underwent a 6-minute exercise trial before and after 12 days of training. Skeletal muscle Na+,K(+)-ATPase concentration was analyzed in gluteus medius and semitendinosus muscle specimens before and after the 12-day training period. Blood samples were collected before and immediately af...
Nishita T, Deutsch HF.Equine muscle carbonic anhydrase (CA-III) behaves like ubiquitin in undergoing extensive acylation of N epsilon-lysine residues upon reacting with p-nitrophenyl esters. The enzyme undergoes extensive carbamoylation of lysine residues when reacted with carbamoyl phosphate. The modification of from 6 to 7 lysine residues results in the production of a series of more anodic electrophoretic components. The derivatization of the lysine residues leads to a marked decrease in the enzyme's ability to hydrate CO2. The equine CA-III possesses both acid and alkaline phosphatase activities in contrast to ...
Enbergs H.Measuring serum or plasma levels of progesterone can be used to determine if conception has occurred in horses. If the mare's progesterone level is below 2 ng/ml 18 days after mating has occurred, conception has not taken place. This method can be used as an addunct to genital examination, and it can be used to determine if hormonal irregularities are present in mares who have not been able to conceive.
Clegg PD.A mature thoroughbred-cross gelding developed chronic severe hindlimb lameness. Despite intensive clinical investigation, the diagnosis of infective arthritis of the coxofemoral joint was difficult, and a definitive diagnosis was reached only after synoviocentesis of the joint. The horse was euthanased and examined thoroughly post mortem but no definitive aetiology for the condition was discovered.
This year's Association of Veterinary Students' congress was held at the University of Liverpool, and included a varied programme, with subjects ranging from the role of large-scale production systems in dairy farming and fertility practices in horses to the importance of recognising and talking about mental health problems within the veterinary profession. Jordan Sinclair, editor of the Journal of the Association of Veterinary Students, reports.
Causey RC, Paccamonti DL, Todd WJ.A total of 22 clinical streptococcal isolates, predominantly Streptococcus zooepidemicus, associated with endometritis in horses were tested for their ability to withstand the natural bactericidal properties of freshly obtained blood. During a 3-hour incubation in blood from a single horse, 8 of these isolates survived and grew, the remainder were killed. To determine whether this ability to grow extended to blood of other horses, 5 of these growing isolates were tested for their ability to grow in the blood of 5 additional horses. The same 5 horses were used for each isolate. The isolates gre...