Veterinary research in horses encompasses the study of diseases, health management, and medical treatments specific to equine species. This field investigates various aspects of horse health, including infectious diseases, metabolic disorders, and musculoskeletal conditions. Researchers focus on understanding the pathophysiology of equine ailments, developing diagnostic tools, and evaluating therapeutic interventions. The study of horse health also involves examining preventive measures such as vaccination protocols and nutritional management to promote overall well-being. This page collects peer-reviewed research studies and scholarly articles that explore the diverse areas of veterinary science related to horses, providing insights into disease mechanisms, treatment strategies, and advancements in equine healthcare.
Putnam MR, Bransby DI, Schumacher J, Boosinger TR, Bush L, Shelby RA, Vaughan JT, Ball D, Brendemuehl JP.Effects of the endophyte Acremonium coenophialum in tall fescue on pregnant mares and foal viability were evaluated. Twenty-two mature pregnant mares were randomly chosen to graze either Kentucky-31 tall fescue that was free from A coenophialum (endophyte-free, EF) or tall fescue infected with A coenophialum (endophyte-present, EP) after the first 90 days of pregnancy through parturition. Concentrations of pyrrolizidine and ergopeptine alkaloids were significantly greater in EP grass, compared with EF pasture. Ten of 11 mares grazing EP pasture had obvious dystocia. Mean duration of gestation ...
Savage CJ, Tidd LC, Ostblom LC, Melsen F, Jeffcott LB.Histomorphometrical analysis of bone biopsies from the wing of ilium in 35 clinically normal horses are reported according to age. The biopsies were collected from 20 mixed-bred foals (mean age 6 +/- 1 months) and 15 older horses (mean age 73 +/- 62 months). No gender differences were found in the group of foals examined, but a significant difference (p less than 0.001) in a number of the primary measurements occurred between them and the older horses. The parameters which altered with age were the extent of osteoid surface (OS/BS), the extent of resorption (erosion) surface (ES/BS), the osteo...
Morris DD, Moore JN.A study was performed to determine prevalence of tumor necrosis factor (TNF) activity in serum of equine neonates with presumed sepsis and to determine correlation between serum TNF activity and severity and outcome of disease. Twenty foals less than 21 days old were considered suitable for inclusion in this study by satisfying clinical and laboratory criteria suggestive of septicemia. At admission, blood samples were collected from all foals for determination of serum TNF activity, then clinical course and outcome of disease were recorded. Thirty-one clinically normal foals less than 21 days ...
Rae C, Board PG, Kuchel PW.In mammalian red blood cells the metabolism of methylglyoxal, and some alpha-ketoaldehydes, takes place via two, generally, highly active enzymes, glyoxalase 1 and 2. The 1H NMR spin-echo spectra of horse erythrocytes, and the various reactants in the glyoxalase system, were characterized as a prelude to obtaining series of spectra in time courses of methylglyoxal metabolism. We characterized the kinetics of the enzyme system in red cells from a normal horse and also from one which had very low activity of glyoxylase 2. The kinetics of the reaction scheme, with methylglyoxal as the starting su...
Gaynor JS, Hubbell JA.Local and regional anesthetic techniques are useful tools for the equine practitioner. These techniques allow surgery to be performed without the risk and cost of general anesthesia. There are, however, risks associated with the local and regional techniques. Neurotoxicity, although rare, may occur when 200 mL or more of a local anesthetic are infiltrated in a short period of time to a 450-kg horse. More likely, horses may become ataxic after nerve blockade in the limbs. This ataxia may lead to self trauma because the horse may not know where the limbs are actually being placed. Although local...
Palmer SE.The use of carbon dioxide and Nd:YAG lasers has expanded the capabilities of equine surgeons. These lasers are used to incise, vaporize, and coagulate tissue with minimal hemorrhage and reduced morbidity to the patient. In this article, practical fundamentals of laser surgery are briefly reviewed, and selected standing laser procedures of the head and neck are discussed.
Ekfalck A, Jones B, Obel N.After a survey of the state of laminitis research the authors conclude that none of the present concepts of the pathogenesis of laminitis unequivocally explains the basic clinical and morphological observations in this disease. There is therefore reason to consider the advances that have been made during the last decades in respect to the influence of various substances on the differentiation of cultured skin keratinocytes. The technique is available for studying hoof keratinocytes in a comparable way. Relevant literature on cultured skin keratinocytes is surveyed. Some of the results from exp...
Gasthuys F, De Moor A, Parmentier D.The effects of calcium chloride administered at low infusion rates on the cardiovascular depression and the blood calcium balance were studied during a constant halothane anaesthesia in dorsally recumbent ventilated ponies. A pronounced cardiopulmonary depression characterized by decreases of all cardiac parameters and lowering of the mean arterial blood pressure was observed after the initial anaesthetic stabilization period of 30 minutes in the ponies. A significant decrease in the total calcium plasma concentration together with a constant ionized and complexed calcium fraction was present ...
Enders AC, Liu IK.The structure of the equine chorionic girdle between days 28 and 42 of gestation was examined. Of particular interest were differentiation of trophoblastic cells within the girdle, adhesion between girdle and endometrium, invasion and displacement of the uterine epithelium, and the nature of the endometrium when girdle cells migrate into it to form endometrial cup cells. The chorionic girdle, identified initially as a band of tall columnar cells, becomes a stratified columnar epithelium indented by clefts and pits. Adhesion to and penetration through the endometrial luminal epithelium are rapi...
Johnston JK, Freeman DE, Gillette D, Soma LR.Sheets of mucosa from the jejunum of healthy horses were mounted in incubation chambers and bathed with Krebs-Ringer bicarbonate solution. Changes in tissue function and histologic appearance were compared after the following conditions: (1) control conditions for 30 minutes with 95% O2/5% CO2 in the gas phase; (2) same conditions as control, except incubation with superoxide dismutase (300 U/ml) during the last 18 minutes; (3) anoxia for 15 minutes with 95% N2/5% CO2, followed by reoxygenation for 15 minutes; (4) same conditions as 3, except incubation with superoxide dismutase during reoxyge...
Su XZ, Morris DD, McGraw RA.We report the molecular cloning and nucleotide sequence of the equine gene encoding tumor necrosis factor alpha. The 2610-bp genomic sequence was derived from three overlapping polymerase chain reaction products.
Deumer J, de Haan F, Tulp MT, van den Hoven R.The effects of an oral isoxsuprine-resin preparation on the blood flow in the thoracic limb of seven horses was determined by thermography. Treatment with the oral resin preparation resulted in increased skin temperatures compared with the non-medicated controls. The maximal temperature differences, 2.2 degrees C for the horses treated with 0.9 mg/kg and 1.8 degrees C for the horses treated with 1.2 mg/kg, occurred four hours after dosing. Plasma total isoxsuprine, determined in three horses, was detectable two hours after oral dosing and maximal eight hours after dosing, but free isoxsuprine ...
Bryant CE, England GC, Clarke KW.The sedative effects in horses of the new alpha 2 agonist medetomidine were compared with those of xylazine. Four ponies and one horse were treated on separate occasions with two doses of medetomidine (5 micrograms/kg bodyweight and 10 micrograms/kg bodyweight) and with one dose of xylazine (1 mg/kg bodyweight) given by intravenous injection. Medetomidine at 10 micrograms/kg was similar to 1 mg/kg xylazine in its sedative effect but produced more severe and more prolonged ataxia, and one animal fell over during the study. Medetomidine at 5 micrograms/kg produced less sedation but a similar deg...
Clabough DL, Levine JF, Grant GL, Conboy HS.The records of 361 Standardbred mares and their 1986 or 1987 foals were evaluated to identify factors associated with failure of passive transfer (FPT) of colostral antibodies in equine neonates. Sixty-five foals (18%) were classified as FPT based on a serum immunoglobulin concentration of less than 400 mg/dl at 24 to 36 hours of age, determined by the glutaraldehyde coagulation test. The potential association of mare- and foal-related factors with FPT were assessed by reviewing a series of multiple logistic regression models. The season in which the mare foaled and foal exam score, a subjecti...
Curran S, Ginther OJ.Accuracy of transrectal ultrasonic diagnosis of fetal gender by identifying and locating the genital tubercle was assessed in 85 horses and 102 dairy heifers and cows. Examinations were made once (horses and cattle) under farm conditions (cattle) on approximately Days 50 to 100. Definite diagnosis was made by removal of fetuses (horses) or after calving or abortion (cattle). In both species and both parities, accuracy was 100% (109 109 totaled over both species) when the certainty level recorded at the time of examination was 95 or 99%. At the lower levels of certainty (65 to 80%, 85 to 90%), ...
Klein WR, Rutten VP, Steerenberg PA, Ruitenberg EJ.Horses with sarcoids, cows with ocular squamous cell carcinoma and dogs with mammary tumors were treated with intralesional injection of Bacillus Calmette Guérin. This treatment appeared to be effective in most cases of equine sarcoids, in 50 - 60% of the cows with ocular squamous cell carcinoma and was not effective in dogs with mammary tumors.
Grünig G, Winder C, Hulliger C, Witschi U, Hermann M, Jungi TW, von Fellenberg R.Increases in procoagulant activities (PCA) in equine lung macrophages were induced by non-adherent blood lymphocytes which were prestimulated with phytohaemagglutinin for 48 to 72 hours or by supernatants harvested from prestimulated blood lymphocyte cultures. However, prestimulated lymphocyte suspensions themselves expressed PCA which was most probably derived from contaminating monocytes. Because non-adherent cells from lymphocyte suspensions may have attached to adherent macrophages, cells within lymphocyte suspensions might have contributed to the PCAs expressed by lymphocyte-stimulated lu...
Meyers PJ, Bonnett BN, McKee SL.This prospective field study was designed to describe the incidence of early embryonic mortality (EEM) and factors associated with the cause of EEM on three equine breeding farms in Ontario during the 1989 breeding season. Early embryonic mortality was defined as the loss of a single embryo during the first 40 days of pregnancy (day 0 = day of ovulation or last breeding). Pregnancy diagnoses and subsequent embryonic losses were observed by serial trans-rectal ultrasonography between days 12-20 (PD1) and 21-30 (PD2), and by trans-rectal ultrasonography or palpation per rectum between days 31-40...
Livesey JH, Carne A, Irvine CH, Ellis J, Evans MJ, Smith R, Donald RA.A 41 amino acid peptide, probably identical in structure to human corticotropin releasing factor, was isolated from 70 equine hypothalami by methanol extraction, immunoaffinity chromatography and single step of reverse phase HPLC. The amino acid sequence was determined by gas phase sequence analysis. Probable carboxyl terminal amidation was demonstrated by similar retention times for equine and human corticotropin releasing factor on reverse phase HPLC at pH 8. The likely structure of equine corticotropin releasing factor is: Ser-Glu-Glu-Pro-Pro- Ile-Ser-Leu-Asp-Leu-Thr-Phe-His-Leu-Leu-Arg-Glu...
Mohammed HO, Hill T, Lowe J.A case-control study was conducted on Thoroughbred horses to identify factors associated with the risk of breakdown on racetracks. A total of 310 cases (breakdowns) were identified from the Horse Identification Department records kept by the chief examining veterinarian of New York Racing Association. For each case, two control horses were selected randomly from the Daily Racing Form Inc. records. Multiple logistic regression analysis was used to identify and quantify the risk of factors associated with breakdown, while simultaneously controlling for the effect of other putative factors. Facto...
Richardson DW, Evans LH, Tulleners EP.Rostral mandibulectomy with primary gingival closure was performed in 5 horses with rapidly growing or bleeding mandibular tumors. The technique involved preservation of the most caudal portion of the mandibular symphysis to maintain stability. There were no surgical complications or recurrences, and the cosmetic and functional results were good. The histopathologic diagnosis of all the tumors was ossifying fibroma. Rostral mandibulectomy affords a simple and effective technique of treating tumors of the rostral portion of the mandible in horses.
Wilson DV, Nickels FA, Williams MA.Benztropine mesylate was used successfully to treat priapism that developed during anesthesia in 2 horses. After IV injection, there was a rapid resolution of signs in both horses, and no side effects were observed. The choice of an effective method to treat priapism is challenging because precise causes in most patients have not been well-defined. Benztropine mesylate is a synthetic compound resulting from the combination of the active portions of atropine and diphenhydramine, and is believed effective because of its central acetyl-choline-antagonizing properties.
King TC, Priehs DR, Gum GG, Miller TR.The records of 50 horses with ocular squamous cell carcinoma (OSCC) presented to the University of Florida Veterinary Medical Teaching Hospital over an 11 year period were reviewed to determine the influence of therapy on the outcome of the case. Follow-up information was obtained for 43 of the 50 cases. The disease was more prevalent in the light horse breeds; however, the draft breeds also were at risk. There was no sex predisposition and the average age was 11.8 years. Tumour recurrence was significant when surgery alone was performed. The eyelid and nictitating membrane were the primary si...
Aramaki S, Suzuki E, Ishidaka O, Momose A, Umemura K.The pharmacokinetics of caffeine (CAF) and its metabolites, dimethylxanthines, were examined in horses administered 2.5 mg/kg of CAF intravenously (i.v.), intramusculary (i.m.), or orally (p.o.). The plasma samples were extracted by Extrelut and the concentrations of CAF and metabolites were determined by high performance liquid chromatography (HPLC) with a short column. The pharmacokinetics of CAF after bolus i.v. injection were described by the assumption of a two-compartment model, and those of CAF after i.m. or p.o. administration were done by the assumption of a one-compartment model. The...
Reeves MJ, Curtis CR, Salman MD, Stashak TS, Reif JS.A survey of 1,965 equine colic cases was conducted from August 1985 to July 1986 at 10 equine referral centers located throughout the United States. The purpose of this study was to develop and validate a multivariable model for the need for surgery. Two-thirds of the cases were randomly selected for model development (1,336), whereas the remaining cases (629) were used only for subsequent validation of the model. If a lesion requiring surgical correction was found at either surgery or necropsy, the case for the horse was classified as surgical, otherwise the case was classified as medical. On...
Szenci O, Brydl E, Bajcsy CA.The stability of blood ionized calcium (Ca2+) and acid-base variables in equine, bovine, ovine, and canine venous blood samples (n = 15, in each group) stored at 4 C for 3, 6, 9, 24, or 48 hours was studied. Variables included blood Ca2+ and standard ionized calcium (Ca2+ corrected to pH 7.4) concentrations, pH, blood carbon dioxide and oxygen tensions, base excess, bicarbonate concentration, and total carbon dioxide content. Results indicate that storage of blood samples at 4 C for up to 48 hours, despite appreciable acid-base changes, is associated with less than 1.5% change in equine, bovin...
Canè V, Botti P, Farneti D, Soana S.The effect of pulsing electromagnetic fields (PEMFs) on bone repair was studied in principal metacarpal bones of eight adult male horses: Six horses were treated with PEMFs, and two horses were untreated. In treated horses, Helmholtz coils were applied during a 60-day period to the left metacarpal bones, bored with eight holes of equal diameter and depth, from the middiaphysis toward the distal metaphysis. Eight equal holes bored in the right metacarpal, surrounded by unactivated Helmholtz coils, were taken as controls. The two untreated horses were taken as additional control. The results of ...
Desjardins MR, Hurtig MB, Palmer NC.The structural integrity of subchondral bone in fresh and frozen osteochondral autografts was investigated at month 3 in 10 horses. Two osteochondral autografts were harvested from the lateral aspect of the lateral trochlear ridge of the left talus in each of 10 anesthetized horses. Grafts were frozen in 7.5% DMSO. After 14 days, the thawed grafts were press-fitted into drill holes in the trochlear ridges of the right stifles. A fresh graft from the right hock was implanted in each left stifle. To control for the effects of surgery, a fresh graft was transferred from the right stifle to the le...
Delbeke FT, Debackere M.It is well known that nikethamide (N,N-diethylnicotinamide, CoramineR) is metabolized very rapidly to nicotinamide. Hence, there is difficulty in proving that nikethamide has been used as a doping substance because nicotinamide is a normal physiological metabolite in the organism as well as a vitamin preparation. However, an intermediate metabolite (N-ethylnicotinamide) was found by us in the urine of horses treated with CoramineR. This was characterized by gas chromatography/mass spectrometry, and synthesized and identified as being N-ethylnicotinamide. The excretion and metabolism of niketha...
Lavado RA, Lewis J, Montgomery JB.Laminitis is a severely debilitating and life-threatening condition that occurs as a consequence of different primary triggering factors. Continuous digital hypothermia (CDH) is recommended in horses at risk of, or diagnosed with, acute laminitis due to its several physiological and biochemical alterations that may be positive for the prevention and early treatment of the condition, representing a low risk of adverse effects. Modulation of the inflammatory response, profound vasoconstriction, and prevention of tissue damage are the most notable protective effects of cryotherapy on the lamellae...
Castro-Mesa AF, Resende Faleiros R, Martínez-Aranzales JR.The transmural ultrasound allows for the definition of the normal appearance of the hoof tissues and internal structures. Determining such measurements and proportions could contribute to evaluations of the normal spatial distal phalanx-hoof relationship. The objective was to describe the hoof's dermis and epidermis measurements using the transmural technique, in comparison with DR and anatomical sections. Sixty-two healthy hooves without digital radiographic abnormalities, made up of 30 anatomical pieces (phase 1) and 32 alive horse hooves (phase 2), and 16 sagittal sections of the first ones...
Bolz NM, Sánchez-Andrade JS, Torgerson PR, Bischofberger AS.The purpose of the study was to determine the diagnostic performance of computed tomographic arthrography (CTA) and 3-Tesla magnetic resonance imaging (MRI) for detecting artificial cartilage lesions in equine femorotibial and femoropatellar joints. Methods: A total of 79 cartilage defects were created arthroscopically in 15 cadaver stifles from adult horses in eight different locations. In addition, 68 sites served as negative controls. MRI and CTA (80-160 mL iodinated contrast media at 87.5 mg/mL per joint) studies were obtained and evaluated by a radiologist unaware of the lesion distributi...
Nishita T, Goto T, Kimura H, Asari M.1. In this study, carbonic anhydrase III (CA-III) content in 18 equine muscles was determined by enzyme immunoassay. 2. It was found to differ in several muscles. 3. That in external intercostal muscle, rectus abdominis muscle and splenius muscle from four horses was very high. 4. Although the masseter muscle had only type I fibers, CA-III content was similar to that in mixed-fiber type muscles such as the biceps femoris muscle. 5. It thus appear that equine type I fibers can be further subgrouped.
Fadok VA.This article discusses some new thoughts on the pathogenesis of four unusual equine dermatoses: reticulated leukotrichia, hyper-esthetic leukotrichia, mane and tail dystrophy, and linear alopecia of the Quarter Horse. Although many of the thoughts contained herein are speculative, it is hoped that they stimulate discussion among those of us interested in the wonderful world of equine dermatology. More importantly, it is hoped that they stimulate further investigation and research. These diseases represent only the tip of the iceberg pf what we don't know about equine skin diseases!
Vasoya D, Tzelos T, Benedictus L, Karagianni AE, Pirie S, Marr C, Oddsdóttir C, Fintl C, Connelley T.The Major Histocompatibility Complex (MHC) genes play a key role in a number of biological processes, most notably in immunological responses. The MHCI and MHCII genes incorporate a complex set of highly polymorphic and polygenic series of genes, which, due to the technical limitations of previously available technologies, have only been partially characterized in non-model but economically important species such as the horse. The advent of high-throughput sequencing platforms has provided new opportunities to develop methods to generate high-resolution sequencing data on a large scale and app...
WEGELIUS O.The number of mast cells per area and volume have been counted in the pleura, pericardium and capsula hepatis of cattle and horse.
The capsula hepatis of cattle contains a 5—10 times larger number of mast cells than the other tissues. The pleura pulmonalis showed a content of mast cells which was only a fraction of that in the liver capsule. The high histamine content found by Riley and coworkers when analyzing ox pleura seem to indicate that histamine is liberated not only from the mast cells, but also from other elements of the tissues.
Pielok A, Kępska M, Steczkiewicz Z, Grobosz S, Bourebaba L, Marycz K.Medicinal signaling cells (MSC) exhibit distinct molecular signatures and biological abilities, depending on the type of tissue they originate from. Recently, we isolated and described a new population of stem cells residing in the coronary corium, equine hoof progenitor cells (HPCs), which could be a new promising cell pool for the treatment of laminitis. Therefore, this study aimed to compare native populations of HPCs to well-established adipose-derived stem cells (ASCs) in standard culture conditions and in a pro-inflammatory milieu to mimic a laminitis condition. ASCs and HPCs were either...
Cancedda M.In this paper some considerations on the environment of the 42 Kmq of the volcanic-basaltic Giara tableland are discussed. Conditioning by the environment and its effect on the distribution of a population of 712 horses is illustrated in view of their social and behavioural organization.