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.
Amory H, Lomba F, Lekeux PM, Solal AN, Jauniaux TP, Desmecht DJ.An adult pony had a 1-month history of severe respiratory distress that was resistant to treatment and environmental changes. Results of blood gas analysis were indicative of alveolar hypoventilation. Simultaneous recordings of thoracic and abdominal wall motion by inductance plethysmography, together with complete pulmonary mechanics evaluation that included transdiaphragmatic pressure monitoring, revealed complete passive behavior of the diaphragm during breathing. Because radiography, necropsy, and histologic examination did not reveal any major lesion to explain the clinical and functional...
Crenon I, Granon S, Chapus C, Kerfelec B.Pancreatic colipase plays an essential role in the intestinal fat digestion by anchoring lipase on lipid/water interfaces in the presence of bile salts. In contrast to other species, two molecular forms of colipase, A and B, have been found in horse. The two corresponding cDNAs were isolated from a horse pancreatic library and their nucleotide sequences were determined. Moreover, for the first time, active colipase has been obtained after transfection of COS cells by either colipase A or B cDNA.
Ford JE, Home WA, Gibson DM.Horse Ig kappa genes have been characterized to determine whether there may be a structural basis for the low level of kappa expression in this species. The overall organization of the J kappa-C kappa locus is remarkably similar to that of the mouse and human loci. A single C kappa exon is separated by 2.9 kb from five J kappa segments, four of which seem functional and three of which are associated with canonical recombination signal sequences. A highly conserved intron enhancer was identified upstream of the C kappa exon and a single restriction fragment in horse genomic DNA hybridized stron...
Badinga L, Michel FJ, Fields MJ, Sharp DC, Simmen RC.Uterine expression of the mRNA encoding antileukoproteinase (ALP) is highest in pig uterus during mid- to late pregnancy, suggesting a stage of pregnancy-dependent role for this elastase/cathepsin G protease inhibitor in feto-maternal interactions. To examine a potential relationship between uterine synthesis of ALP and the type of placentation in mammalian species, the expression of ALP mRNA and/or protein in pregnant mares, cows, rats, and mice was evaluated. Genomic DNA and mRNA hybridization analyses were performed using a porcine ALP cDNA as probe. The concentration of ALP protein in repr...
Ferreira-Dias G, Nequin LG, King SS.Pathologic changes in the endometrium of mares may be rated according to Kenney's method of classification. Category I endometrium contains healthy tissue with no or few widely scattered pathologic changes. At the opposite end, severe widespread pathologic changes are associated with category III. Uterine biopsy specimens were collected aseptically from 16 mares during the estrous and diestrous stages of the cycle. Pathologic changes were evaluated, using light microscopy, and endometrium was classified as Kenney's category I, II, or III. Endometrial tissue of category I (n = 5 mares in estrus...
Teifke JP.From 932 equine skin lesions 421 were diagnosed as sarcoids (about 45%). The most common locations were the ventral body regions, head, neck and sites of thin skin. Most often the fibroblastic type, less frequently the mixed type and most infrequent the verrucous type of sarcoid were diagnosed. Detection of BPV-DNA was performed by polymerase chain reaction (PCR) using an oligonucleotide primer pair located in the E5-open reading frame. DNA of BPV 1 and BPV 2 could be differentiated by digestion with restriction endonucleases. In 97 out of 108 sarcoids BPV-DNA was detected by PCR. Most samples...
Stadler P, Kinkel N, Deegen E.In 14 horses without heart disease stroke volume determination were established by pulsed wave doppler echocardiography. Thermodilution and doppler echocardiography were used simultaneously. The doppler echocardiographic volume determinations were carried out in left and right outflow tracts. Echocardiographically Velocity Time Integral, Maximum Flow Velocity, Mean Flow Velocity and Acceleration Time were ascertained. To be able to compare heart volumes of horses with different body weight stroke volume was applied to 1 kg of body weight (= heart index). Heart Index determined with thermodilut...
MacDonald MH, Stover SM, Willits NH, Benton HP.The metabolic responses of equine articular cartilage to incubation with bacterial lipopolysaccharide (LPS) were studied, using explant cultures of articular cartilage obtained from the metatarsophalangeal joints of 15 horses, age of which ranged from 3 months to 20 years. For comparison, explants were also established from the metatarsophalangeal joints of 3 calves. Explants were cultured for 3 days in medium containing various concentrations of LPS from 0 (control) to 100 micrograms/ml. Glycosaminoglycan (GAG) released during the 3-day incubation was determined by a spectrophotometric assay,...
Thomas PG, Ball BA, Brinsko SP.Regulation of attachment of equine spermatozoa to homologous oviduct epithelium was investigated by co-culture of spermatozoa with oviductal epithelial cell explants. Stallion spermatozoa were incubated with explants derived from the isthmus and ampulla of follicular, postovulatory, and diestrous mares. Steroid treatments (estradiol, progesterone, or control) were applied across all explant groups. Estimates of motility and total numbers of attached spermatozoa were made 0.5, 24, and 48 h after initiation of co-culture. Equine spermatozoa attached by their rostral acrosomal region to both cili...
Fulton IC, MacLean AA, O'Rielly JL, Church S.Bilateral superior check ligament desmotomy was performed on 31 Thoroughbred and 17 Standardbred horses as the sole method of treatment for superficial digital flexor tendonitis. Horses resumed racing between 6 and 19 months after surgery. Horses that were able to compete in 5 or more races without injury to the tendon again were considered to have had a successful return to racing. Twenty-five Thoroughbreds were suitable for later study and 13 of these (52%) raced on 5 or more occasions. Fifteen Standardbreds were suitable for later study and 10 of these (66%) raced on 5 or more occasions. Wi...
Ishida N, Hasegawa T, Takeda K, Sakagami M, Onishi A, Inumaru S, Komatsu M, Mukoyama H.The D-loop regions in equine mitochondrial DNA were cloned from three thoroughbred horses by polymerase chain reaction (PCR). The total number of bases in the D-loop region were 1114 bp, 1115 bp and 1146 bp. The equine D-loop region is A/T rich like many other mammalian D-loops. The large central conserved sequence block and small conserved sequence blocks 1, 2 and 3, that are common to other mammals, were observed. Between conserved sequence blocks 1 and 2 there were tandem repeats of an 8 bp equine-specific sequence TGTGCACC, and the number of tandem repeats differed among individual horses....
Hjertén G, Drevemo S.The initial forelimb loading of a horse trotting at 3.7 ms-1 on a treadmill was studied by use of an instrumented shoe, accelerometers and high-speed cinematography. At the beginning of the stance phase the forelimb was loaded successively from the hoof. This is suggested to be an important factor for effective shock force absorbency in the extremities. Shearing forces may appear in the carpus before the onset of the longitudinal loading of the limb. These forces are proposed to depend on speed, locomotion pattern and the friction and hardness of the surface. It is suggested that shearing forc...
Cohen ND, Neibergs HL, Wallis DE, Simpson RB, McGruder ED, Hargis BM.Members of the genus Salmonella were identified in feces from horses, using the polymerase chain reaction (PCR) and genus-specific oligonucleotide primers. Feces from healthy horses were determined to be culture-negative for Salmonella spp. Fecal samples were inoculated with known numbers of colony-forming units (CFU) of S anatum, S derby, S enteritidis, S heidelberg, S newport, and S typhimurium. The DNA was extracted from fecal samples and amplified by PCR, using genus-specific primers. Sensitivity of the assay extended to 10(3) CFU of Salmonella sp/g of feces; sensitivity of microbiologic c...
Palma F, Ligi F, Soverchia C.This work is a comparative study of Na(+)-K+ and Ca(2+)-Mg2+ ATPase associated with the erythrocyte plasma membranes in different mammals. The method used to test the activity of these enzymes is based on quantitative measurements of ADP released during the reaction with HPLC: the chromatographic type is an Ion-Pair Reversed Phase. We have found that the levels of Ca2+ stimulated ATPase are higher than those of Na(+)-K+ ATPase in red blood cells of all the different mammalian species, with the only exception being lamb erythrocytes where the values of both the ATPase activities are almost equa...
Milne EM, Pemberton AD, McGorum BC, Dixon PM, Miller HR.The equine alpha-1 proteinase inhibitor (alpha 1PI) system differs from that of man in that the equine system consists of four closely-linked genes (Spi1-Spi4) whereas in man, a single gene encodes for alpha 1PI. We have previously found differences in the proportion of the Spi proteins in equine serum and bronchoalveolar lavage fluid (BALF). We therefore wished to determine whether, as reported in man, there was any molecular weight difference between the Spi proteins in serum and BALF. alpha 1PI and albumin from equine BALF migrated further towards the anode compared with serum alpha 1PI on ...
Sonea IM, Bowker RM, Robinson NE, Broadstone RV.Distribution of pulmonary nerves immunoreactive for either substance P or calcitonin gene-related peptide was determined, using immunohistochemical methods on healthy lungs from adult equids. The overall patterns of distribution of substance P and calcitonin gene-related peptide-like immunoreactivity were similar. Distribution of immunoreactive nerves was not uniform throughout the lungs; nerve fibers immunoreactive for these peptides were more frequently observed near the hilus of the lung than in the caudal lobes or in the periphery of the lung. Nerve fibers immunoreactive for substance P or...
Beelitz P, Rieder N, Gothe R.In this epidemiological study 30 mares and their foals from seven farms in Upper Bavaria were investigated. Eimeria-leuckarti-oocysts were found in 24 foals (80%), but only in one mare. Oocysts were first detected 28 days post partum at the earliest and 191 days post partum at the latest. In foals, excretion of oocysts usually occurred intermittently with coproscopically negative intervals of up to 15 weeks, and was most frequent in June (8 foals), July (17 foals), and August (10 foals). With the exception of two animals which had mild diarrhoea, the oocyst-shedding foals showed no clinical si...
Osame S, Ichijo S.Seven cases of thoroughbred foals kept on a farm in the Hidaka district of Hokkaido showed bilateral thyroid enlargement from 3 or 4 months after birth. Their serum T4 levels were remarkably low, whereas T3 levels were in the normal range. Serum T4 levels were also low in the other clinically normal foals and their dams kept together. Since the iodine content in pasture soil and grass was very low, iodine deficiency was supposed to be the cause of the disease.
Acharya KR, Stuart DI, Phillips DC, McKenzie HA, Teahan CG.Similarities in amino acid sequences, three-dimensional structures, and the exon-intron patterns of their genes have indicated that c-type lysozymes and alpha-lactalbumins are homologous proteins, i.e., descended by divergent evolution from a common ancestor. Like the alpha-lactalbumins, echidna milk, horse milk, and pigeon eggwhite lysozymes all bind Ca(II). Models of their three-dimensional structures, based on their amino acid sequences and the known crystal structures of domestic hen eggwhite and human lysozymes and baboon and human alpha-lactalbumins, have been built. The several structur...
Denoix JM.Tendons and ligaments of the equine distal limbs have a prominent anatomic, functional, and clinical importance. This article reviews the descriptive and topographic anatomy of these structures in details. Special information is given about the mechanical properties and functional anatomy of the flexor tendons, accessory ligaments, and third interosseous muscle, as well as about their roles during the standing position and gaits.
Messick JB, Rikihisa Y.The effects of equine antiserum, immunoglobulin G (IgG) specific for Ehrlichia risticii, and its Fab fragment on E. risticii binding to, internalization into, and proliferation in P388D1 cells were studied by immunofluorescence flow cytometry. Anti-E. risticii equine serum or IgG inhibited E. risticii at a stage beyond binding and internalization. In contrast, monovalent anti-E. risticii equine Fab fragments inhibited E. risticii binding and internalization into P388D1 cells. In the presence of control equine serum, IgG, or its Fab fragment, E. risticii cells were bound, were internalized and ...
Svalastoga E, Reimann I, Nielsen K.Histological and histochemical investigations of the fibrocartilage of facies flexoria from navicular bones of horses with navicular disease have shown alterations similar to those described in the hyaline articular cartilage in osteoarthritic joints.
Jones LE, Dyson SJ.To describe in detail the radiographic appearance of ossified ungular cartilages in horses and to evaluate the usefulness of a flexed dorsolateral-palmaromedial oblique (flexed oblique) radiographic view in evaluating the ungular cartilages. Methods: Retrospective case series. Sample-Radiographs of 1,255 front feet of horses. Methods: Ossification of the ungular cartilages was graded during evaluation of radiographs on a scale from 0 to 5; feet with cartilages with an ossification grade ≥ 2 were included (386 feet [271 horses]). The shape (straight, curved outward or inward, and dorsopalmar ...
Gross DK, Morley PS, Hinchcliff KW, Reichle JK, Slemons RD.The purpose of this investigation was to determine if naturally occurring acute infectious upper respiratory disease (IRD) caused by equine influenza virus is associated with ultrasonographically detectable pleural and pulmonary abnormalities in horses. Standardbred racehorses were evaluated for signs of IRD, defined as acute coughing or mucopurulent nasal discharge. For every horse with IRD (n = 16), 1 or 2 horses with no signs of IRD and the same owner or trainer (n = 30) were included. Thoracic ultrasonography was performed within 5-10 days of the onset of clinical disease in horses with IR...
Jones DL, Barber SM, Jack SW, Doige CE.Gross and microscopic effects of arthroscopic partial synovectomy on synovium and articular cartilage of middle carpal joints were studied in 15 horses. A 7-mm diameter motorized synovial resector was inserted into each middle carpal joint and arthroscopic partial synovectomy and lavage or arthroscopic lavage alone was performed. Study periods were 0 (three horses), 16 (three horses), and 30 days (six horses). No gross evidence of degenerative joint disease was observed at day 16 or 30. At 30 days, resected areas lacked villi and there was deposition of fibrin on the synovial surface with vary...
Manohar M, Goetz TE, Rothenbaum P, Humphrey S.The present study was carried out to examine whether pentoxifylline administration to horses premedicated with frusemide would attenuate the exercise-induced pulmonary arterial, capillary and venous hypertension to a greater extent than frusemide alone, thereby affecting the occurrence of exercise-induced pulmonary haemorrhage (EIPH). Using established techniques, we determined right heart and pulmonary vascular pressures in 6 healthy, sound Thoroughbred horses at rest and during exercise performed at maximal heart rate at a workload of 14 m/s on 3.5% uphill grade in the control (no medication...
Brankston G, Rossi TM, O'Sullivan TL, Greer AL.This retrospective study describes testing patterns and the incidence of subsp. in Ontario to assess the utility of laboratory data for surveillance purposes. Laboratory records for equine infectious disease test submissions were extracted from the Animal Health Laboratory (AHL) at the University of Guelph for the years 2008 to 2018. Yearly and seasonal trends in testing and the proportion of tests that returned positive results were assessed. The number of samples submitted for testing decreased over the 11-year period (odds ratio = 0.96, 95% confidence interval: 0.92 to 0.999; = 0.04). ...
Senderska-Płonowska M, Zielińska P, Żak A, Stefaniak T.Heel contraction is an undesired but common condition in domestic horses. Some authors indicate shoeing as a risk factor. There is a correlation between shoeing and a restriction of heel expansion, but the clinical significance is unknown. This study aimed to evaluate the influence of shoeing and other risk factors, such as age, access to paddock, and breed, on heel contraction. This study included 114 horses, 55 of which were barefoot their whole life and 59 had been shod consistently for at least the previous year. The width and length of the frog were measured. Linear mixed-effects models w...
McD￮ LA.Stem cell therapy and cell-based therapies using other progenitor cells are becoming the treatment of choice for many equine orthopedic lesions. Important criteria for obtaining autogenous equine progenitor cells in vitro for use in clinical cell-based therapy include the ability to isolate and expand cells repeatedly to high numbers (millions) required for therapy, in a clinically relevant time frame. Cells must also maintain their ability to differentiate into the tissue type of choice. The objective of this study was to compare isolation and expansion techniques for preparation of periostea...
Rowe Á, Flanagan S, Barry G, Katz LM, Lane EA, Duggan V.Warmblood Fragile Foal Syndrome (WFFS) is an autosomal recessive disorder caused by a mutation in the procollagen-lysine, 2-oxoglutarate 5-dioxygenase 1 (PLOD1) gene. Homozygosity for the mutation results in defective collagen synthesis which clinically manifests as the birth of non viable or still born foals with abnormally fragile skin. While the mutation has been identified in non Warmblood breeds including the Thoroughbred, to date all homozygous clinically affected cases reported in the scientific literature are Warmblood foals. The objective of this study was to investigate the carrier f...
Sentsui H, Wu D, Murakami K, Kondo T, Matsumura T.Recombinant equine interferon-gamma (reIFN-gamma) was prepared using a baculovirus expression system and its antiviral activity was investigated using several equine viruses. The reIFN-gamma suppressed the replication of all equine viruses used in the present experiment in horse cell cultures, but did not affect the growth of host cells at concentrations of less than 1000 u/ml. A strong antiviral effect was observed, especially against RNA viruses. Equine picornavirus, equine rhinovirus and equine arteritis virus could not be propagated at all in 100 u/ml reIFN-gamma when 100 TCID(50) of infec...
Adam E.Emma Adam of the Gluck Equine Research Center at the University of Kentucky in the USA provides an update on rotaviruses, particularly the group B equine rotavirus identified in 2021.
Baptiste KE, Grahn BH.The clinical manifestations, laboratory findings, and survival times of 10 horses with orbital neoplasms are reported. In all cases, orbital neoplasms were malignant and locally invasive with no defined surgical circumscribed edges. It was often difficult to identify the primary cell type of the neoplasia in histologic specimens due to the poorly differentiated, anaplastic nature of the majority of cases. All except one horse were eventually euthanized 2 mo to 5 y after diagnosis due to poor response to treatment, metastasis, or unrelenting orbital neoplasia. Mean survival time increased with ...
Jakowski RM.The case records of 17 horses with atrophy of the right hepatic lobe were reviewed. Fifteen horses had signs of colic. Two horses had clinical problems that were unassociated with gastrointestinal tract disease. Ages ranged from 5 to 30 years (mean, 12.6 years) and there was no breed or sex predisposition. In clinically normal horses, the right hepatic lobe constitutes half of the total liver weight. The right hepatic lobe in the 17 horses in this study ranged from 11.0 to 38.3% of the total liver weight (mean, 27.8%). Findings on histologic examination of hepatic tissue from horses in the stu...
Casbeer HC, Knych HK.Tolazoline is an α2-adrenergic receptor antagonist, used in veterinary medicine to antagonize the central nervous system depressant and cardiovascular effects of α2 receptor agonists. The pharmacokinetics and pharmacodynamic effects of tolazoline when administered subsequent to detomidine in the horse were recently reported, although the reversal of the sedative and cardiovascular effects following detomidine may not be complete. The current study therefore investigated the pharmacokinetics and pharmacodynamic effects of tolazoline when administered as a sole agent. Nine healthy adult horses...
Ramsey GD, Hunter PJ, Nash MP.In the treatment of laminitis it is believed that reducing tension in the deep digital flexor tendon by raising the palmar angle of the hoof can reduce the load on the dorsal lamellae, allowing them to heal or prevent further damage. Objective: To determine the effect of alterations in hoof angle on the load in the dorsal laminar junction. Methods: Biomechanical finite element models of equine hooves were created with palmar angles of the distal phalanx varying from 0-15°. Tissue material relations accounting for anisotropy and the effect of moisture were used. Loading conditions simulating t...
Siemsen DW, Kirpotina LN, Malachowa N, Schepetkin IA, Porter AR, Lei B, DeLeo FR, Quinn MT.The development of new advances in understanding the role of neutrophils in inflammation requires effective procedures for isolating and purifying neutrophils. Methods for isolating human neutrophils are fairly standard, and some are covered in other chapters of this volume and previous editions. However, procedures for isolating neutrophils from nonhuman species used to model human diseases vary from those used in isolating human neutrophils and are not as well developed. Since neutrophils are highly reactive and sensitive to small perturbations, the methods of isolation are important to avo...
Tulloch JSP, Fleming KM, Pinchbeck G, Forster J, Lowe W, Westgarth C.Animal-related injuries pose a significant risk to the veterinary profession. This study aimed to describe the incidence, demographics, context and consequences of animal-related injuries at UK veterinary schools. A multicentre audit of accident records (2009-2018) across five UK veterinary schools was performed. Injury rates were stratified by school, demographics and species. The context and cause of the injury were described. Multivariable logistic models explored factors associated with medical treatment, hospital visits and time off work. An annual rate of 2.60 (95% confidence interval 2....
de Souza TC, Suthers JM, Busschers E, Burford JH, Freeman SL.Synovial sepsis is a frequent cause of morbidity and mortality in horses. Despite advances in diagnostics and treatments, persistent infection or chronic lameness can occur. Objective: To perform a scoping review to identify and evaluate the current evidence on the factors implicated in the success of treatment for synovial sepsis. Methods: Joanna Briggs Institute scoping review. Methods: A protocol was registered, and a systematic literature search was performed on CAB abstracts, Medline, Scopus and Embase. Inclusion and exclusion criteria were developed and studies systematically reviewed ag...
Gunning P, Smith A, Fox V, Bolt DM, Lowe J, Sinclair C, Witte TH, Weller R.Lameness is the most common presenting complaint in equine practice. Performing diagnostic nerve blocks is an integral part of any lameness work-up, and is therefore an essential skill for equine practitioners. However, the opportunities for veterinary students to practice this skill are limited. The aim of this study was to design and validate an equine nerve block simulator. It was hypothesised that the simulator would improve students' ability and enhance their confidence in performing nerve blocks. A simulator was built using an equine forelimb skeleton and building foam. Wire wool targets...
Broyles AH, Embertson RM, Brett Woodie J, Machado V.There is persistent concern among some trainers, owners and veterinarians regarding the effect of preoperative laryngeal function grade on the outcome of laryngoplasty and ventriculocordectomy (LPVC). Objective: To determine the effect of laryngeal function grade prior to LPVC on postoperative performance. Methods: Retrospective case-series. Methods: Medical and race records of Thoroughbred racehorses diagnosed with recurrent laryngeal neuropathy (RLN) and treated with LPVC between 1998 and 2013 were reviewed. Horses were placed into three groups based on preoperative laryngeal function grade ...
Haschek WM, King JM, Tennant BC.Of 2 horses with renal cell carcinoma, 1 had massive ascites but no other signs of urinary tract disease; the other had hematuria. In both horses, the tumors were palpable as large perirenal masses. The tumor mass of horse 1 almost completely replaced the left kidney, and there were tumor implants on the serosa of abdominal organs. The right kidney of horse 2 was compressed peripherally by the tumor, which completely filled the renal pelvis. The prevalence of renal cell carcinoma in horses and dogs necropsied at the New York State College of Veterinary Medicine between 1953 and 1976 was simila...
Stick JA, Boles C.Three foals with chronic cough, bilateral nasal discharge, and pneumonia were found to have a subepiglottic cyst as the inciting cause. Consistent findings were dysphagia and aspiration pneumonia, in addition to the abnormal respiratory noise usually found in the adult horse with a subepiglottic cyst. Histologic examination of the cysts suggested their origin was traumatic rather than embryonic.
Wheeler SJ.Sensory nerve conduction velocity was measured in the lateral palmar nerve of 8 horses. The limb temperature was manipulated by external means and monitored. Alterations in the nerve conduction velocity related to limb temperature variation were identified at both increased and decreased temperatures. These were quantified and a mean value of 2.15 +/- 0.2 m/s/degree Celsius was determined. The effect of altered limb temperature should be considered in nerve conduction velocity determinations.
