The study of diseases in horses encompasses a wide range of conditions affecting equine health, including infectious diseases, metabolic disorders, and genetic abnormalities. These diseases can impact various systems within the horse, such as respiratory, gastrointestinal, and musculoskeletal systems, and can lead to significant health challenges. Research in this area focuses on understanding the pathophysiology, diagnosis, prevention, and treatment of equine diseases. Common diseases studied include equine influenza, equine herpesvirus, and laminitis. This page provides access to peer-reviewed research studies and scholarly articles that explore the etiology, clinical presentation, and management strategies of diseases in horses, contributing to the advancement of equine veterinary medicine.
Reilly LK, Palmer JE.Four foals were admitted to the neonatal intensive care unit in the first 2 days of life with problems related to birth hypoxia (neonatal maladjustment syndrome, renal failure, necrotizing enterocolitis) and sepsis. Foals were hospitalized for an extended period (35 to 70 days) and received treatment with several broad spectrum antimicrobial agents. Invasive monitoring and treatment procedures included intravenous catheterization, urinary catheterization, and parenteral nutritional and ventilatory support. In each foal, infections of undetermined cause developed, and systemic candidiasis was d...
Imagawa H, Ishida S, Uesugi S, Masanobu K, Fukunaga Y, Nakagomi O.Serotype G3 equine rotaviruses isolated in Japan made up a common genogroup and were classified into two different genotypes. The genomes of serotype G3 equine rotaviruses with an identical electropherotype (isolated from 1982 to 1989) were very closely related to each other regardless of the year in which they were isolated. Serotype G3 equine rotavirus BI originating from England belonged to the same genogroup of serotype G3 equine rotaviruses isolated in Japan, although BI was classified as having a different genotype. The genomes of both serotype G10 equine rotavirus R-22 and serotype G10 ...
Tanimoto T, Yamasaki S, Ohtsuki Y.A well-demarcated solitary splenic mass (20 x 20 x 15 cm in size) containing hemorrhagic and necrotic foci was observed in a 4-year-old Thoroughbred stallion. Histologically, the mass consisted of lymphoma cells of the diffuse large non-cleaved type, with a high mitotic index and scattered macrophages that formed a starry sky pattern. The lymphoma cells revealed diffuse positivity for acid phosphatase and alpha naphthyl butyrate esterase, and were also positive for intracytoplasmic IgM on occasion, and mostly for proliferating cell nuclear antigen. Ultrastructural examination revealed moderate...
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.
Cobbold S, Holmes M, Willett B.There is now a wide range of immunological reagents that can be used in the diagnosis and treatment of diseases in the companion animals (dogs, cats and horses). Many of these diseases are the veterinary equivalents of human conditions, and may therefore provide good models to study basic pathogenic mechanisms.
Slater JD, Borchers K, Thackray AM, Field HJ.Four specific pathogen-free ponies were infected intranasally with equine herpesvirus 1 (EHV-1) and two were similarly infected with an EHV-1 thymidine kinase deletion mutant. The primary infections were characterized by a transient fever accompanied by virus shedding into nasal mucus and viraemia. No virus was detected in clinical specimens after 15 days post-infection. Two months later a reactivation stimulus was administered to all six ponies and only the four that had been previously inoculated with wild-type EHV-1 shed virus into nasal mucus (for 10 days), proving the presence of a latent...
Boschwitz JS, Timoney JF.The antiphagocytic property of equine fibrinogen for Streptococcus equi subsp. equi strain CF32 was examined in vitro. The results of bactericidal assays demonstrated that the presence of fibrinogen enhanced the ability of overnight and early log-phase cultures of strain CF32 to resist killing by equine neutrophils by 12-fold and seven-fold, respectively (p > 0.01). In addition, fibrinogen-coated bacteria treated with fibrinogen specific F(ab')2 fragments were 32% more susceptible to killing by equine neutrophils after opsonization in serum (p > 0.05), indicating that specific epitopes o...
Valentine BA, Rousselle SD, Sams AE, Edwards RB 3drd .Three horses with fibrotic myopathy were examined for neuromuscular disease. In 2 horses, concentric needle electromyography was performed. Dense spontaneous activity suggestive of denervation, was found in multiple thigh muscles of 1 of the 2 horses. All 3 horses were euthanatized. Histochemical and histologic examination of tissue specimens was performed. All horses had degenerative lesions in peripheral and intramuscular nerves. Angular atrophy of type-1 and type-2 muscle fibers, indicative of denervation atrophy, was seen in multiple muscle specimens from all 3 horses. One horse was found ...
Frankeny RL, Johnson PJ, Messer NT, Keegan KG, Corwin LA.A 7-month-old Appaloosa foal had bilateral hind limb lameness and was unable to rise from recumbency without assistance. Lameness could be exacerbated by tarsal flexion and a firm swelling at the distomedial aspect of the tibias was associated with a marked pain response when palpated. Radiography revealed enlargement of the distal tibial metaphysis physis (compared with normal), and radiolucent fissure lines extending proximally from the physis into the metaphysis at its medial aspect. Treatment included rest and dietary adjustment. Although clinical signs initially resolved following treatme...
Ferreira-Dias G, Nequin LG, King SS.Equine endometria representative of Kenney's categories I, II, and III were incubated in vitro with phosphate buffer, Streptococcus pneumoniae, or S zooepidemicus. Endometrial tissues from mares in estrus and diestrus were first categorized according to Kenney's classification, then were tested for adherence of S pneumoniae and S zooepidemicus to the epithelia. Bacteria were not observed when the endometrial tissue was incubated with phosphate buffer or S pneumoniae. There was no statistical difference in attachment of S zooepidemicus to endometrial tissue from mares in estrus or diestrus if e...
Petsche VM, Derksen FJ, Robinson NE.Tidal breathing flow-volume (TBFV) loops were determined in a group of control horses and in horses affected with recurrent airway obstruction (heaves). The latter group was studied when the condition was in remission and under increasing amounts of airway obstruction as reflected by measurements of change in pleural pressure, pulmonary resistance, and dynamic compliance. The TBFV loops of control horses had biphasic inspiratory and expiratory patterns; peak inspiratory and peak expiratory flows were detected early in inspiration and expiration, respectively. Tidal volume was unaffected by hea...
Buechner-Maxwell V, Zhang C, Robertson J, Jain NC, Antczak DF, Feldman BF, Murray MJ.Leukemia is a neoplastic disease of one or more of the cell types of the hemopoietic system and is rarely diagnosed in the horse. This report describes a case of subleukemic acute myelomonocytic leukemia in an 11-year-old gelding. Preliminary cytological diagnosis was supported by two types of laboratory investigations. Cytochemical characterization of blood and bone marrow neoplastic cells was consistent with a myelomonocytic origin. Neoplastic blast cells in peripheral blood were labeled by monoclonal antibodies specific for cell surface molecules of horse granulocytes, but they were not lab...
Zicker SC, Rogers QR.Concentrations of amino acids in plasma and whole blood in response to 10 hours of food deprivation were determined in healthy 2-day-old foals (n = 8) and were compared with control values in foals of the same age (n = 8) allowed free access to suckle. In addition, response of concentrations of amino acids in plasma to 15 minutes of free-access suckling was determined at the end of the 10-hour period in both groups. Response of 13 amino acids in plasma of food-deprived foals was significantly (P < 0.05) different, compared with that in control foals. Concentrations of 3 amino acids (alanine...
LeBlanc M, Neuwirth L, Mauragis D, Klapstein E, Tran T.The effects of oxytocin on the percentage of technetium 99m albumin colloid (99mTc-microAA), cleared from the uterine lumen was measured in 13 mares. Scintigraphy was performed during 4 consecutive oestrous cycles, on Day 3 of oestrus during Cycles one and 3 and 48 h after ovulation during Cycles 2 and 4. Oxytocin (20 iu) was given i.v. after the initial scintigraphy image during Cycles 3 and 4. Seven multiparous mares (Group 1) were classified as 'susceptible' and 6 mares (2 nulliparous and 4 multiparous; Group 2) were classified as 'resistant' to endometritis. All mares cleared > 90% of 99mT...
Bernoco MM, Liu IK, Willits NH.Six foals were deprived of colostrum for the first 36 hours after birth and, instead, received reconstituted powdered milk. Five control foals suckled their dams naturally. Blood samples were obtained from all the foals after birth and at approximately weekly intervals until at least 5.5 months of age. Sera were analyzed for hemolytic complement activity, complement component C3, and correlating IgG concentration. Hemolytic complement (P = 0.0145) and C3 (P = 0.0002) values were significantly higher in colostrum-deprived foals (CDF) than in naturally nursed foals at 2 to 5 days of age. In addi...
MacDonald DG, Morley PS, Bailey JV, Barber SM, Fretz PB.Post operative surgical wound infection rates were determined 452 cases of equine orthopaedic surgery performed at the Western College of Veterinary Medicine, Saskatoon, Saskatchewan, between January 1, 1981 and December 31, 1990. Only surgical procedures classified as clean or clean-contaminated by the National Research Council were included in this study. The overall post operative infection rate was 10.0% (45 of 452). Clean surgeries (n = 433) had an 8.1% infection rate while clean-contaminated surgeries (n = 19) had a 52.6% infection rate. Information collected from the medical records was...
Martinez-Torrecuadrada JL, Iwata H, Venteo A, Casal I, Roy P.African horsesickness virus (AHSV) is a gnat-transmitted member of the Orbivirus genus of the Reoviridae family. The virus has a genome of 10 double-stranded RNA species (L1-L3, M4-M6, S7-S10). The L2 and M6 genes of AHSV serotype 4 (AHSV-4) which encode the outer capsid proteins VP2 and VP5, respectively, were inserted into recombinant baculoviruses downstream of the baculovirus polyhedrin, or p10 promoters. Recombinant baculoviruses expressing VP2, VP5, or VP2 and VP5 proteins of AHSV-4 were isolated. The expressed AHSV proteins were similar in size and antigenic properties to those of viral...
Tetens J, Tulleners EP, Ross MW, Orsini PG, Martin BB.Tympany of the auditory tube diverticulum was treated in 2 Standardbred foals by fenestrating the median septum, using an endoscopically placed Nd:YAG laser. Recurrence in 1 foal was treated by enlarging the fenestration, using a modified Whitehouse approach, and the pharyngeal opening of the auditory tube. Use of the Nd:YAG laser eliminates the risk of inadvertent cranial nerve damage associated with incisions into the auditory tube diverticulum. The procedure can be performed with the horse sedated or anesthetized. Clinical signs can recur in the fenestration heals closed or if the condition...
Messer NT, Johnson PJ.Acute hepatic disease was diagnosed in 16 horses during the study period. Twelve of those cases were characterized as idiopathic acute hepatic disease (IAHD). In 9 of the 12 (75%) cases of IAHD, the horses were female, and 7 of the 9 females were lactating and had been treated with tetanus antitoxin at parturition. Diagnosis of IAHD was based on anamnesis, clinical signs, and results of serum biochemical analyses, hepatic biopsy, and postmortem examination. Within 1 year of the illness, 75% (9/12) of the horses had died or had been euthanatized. Not all horses had the typical fulminant signs a...
Science (New York, N.Y.)June 10, 1994
Volume 264, Issue 5165 1584-1587 doi: 10.1126/science.7515512
Willbold D, Rosin-Arbesfeld R, Sticht H, Frank R, Rösch P.Trans-activator (Tat) proteins regulate the transcription of lentiviral DNA in the host cell genome. These RNA binding proteins participate in the life cycle of all known lentiviruses, such as the human immunodeficiency viruses (HIV) or the equine infectious anemia virus (EIAV). The consensus RNA binding motifs [the trans-activation responsive element (TAR)] of HIV-1 as well as EIAV Tat proteins are well characterized. The structure of the 75-amino acid EIAV Tat protein in solution was determined by two- and three-dimensional nuclear magnetic resonance methods and molecular dynamics calculatio...
Rousseaux CG, Futcher KG, Clark EG, Naylor JM.Two cases of cauda equina neuritis are compared and contrasted. Neurological deficits of the tail and perineum were noted and functional deficits were seen in gait, urination, defecation and cranial nerve function. Lesions consisted of nonsuppurative inflammation of the nerve trunks and proliferation of the perineurium of the cauda equina. Cranial nerve involvement in one case supported a diagnosis of polyneuritis equi rather than cauda equina neuritis. The possible etiologies and pathogenesis of this disease are discussed.
Cruz AM, Barber SM, Kaestner SB, Townsend HG.Anomalies of the urethra are uncommon. Urethrorectal fistula in horses has only been reported in foals and only in conjunction with other congenital anomalies. This report describes the diagnosis, surgical management, and possible etiologies of a unique case of urethrorectal fistula in a mature gelding.
Morisset S, Hawkins JF, Frank N, Sojka JE, Berg D, Blevins WE.A 2-day-old male foal developed uroperitoneum. Initial exploration of the abdomen via ventral midline celiotomy failed to localize the source of uroperitoneum. Bilateral nephropyelocentesis and antegrade urography were performed, and a defect in the right ureter and stenosis of the left ureter were identified. With the foal in dorsal recumbency in the Trendelenburg position, ureterorrhaphy was performed on the right ureter. After ureterorrhaphy, a ureteral catheter was maintained as a stent. The stenotic left ureter was transected, and ureteroneocystostomy was performed using a drop-in mucosal...
Traub JL, Rantanen N, Reed S, Schecter L.Four cases of cholelithiasis in horses were reviewed. Two horses were examined because of recurrent abdominal pain. Clinical laboratory data, results of physical examination, and history indicated biliary obstruction. In 1 case, B-mode ultrasonography aided in the diagnosis, which was confirmed at necropsy. In 2 horses, the biliary calculi were incidental necropsy findings.
Cole SD, Stefanovski D, Towl S, Boyle AG.There is a lack of epidemiological studies about equine subsolar (hoof) abscesses even though they are among one of the most common causes of acute, severe lameness. The goals of this study were to (1) describe the equine subsolar abscess patient population of the University of Pennsylvania's New Bolton Center's Field Service and (2) to determine the factors that are associated with increased veterinary visits, prolonged treatment and complications. Descriptive statistics were performed on data collected from 160 cases of equine subsolar abscess. Inferential statistics were performed on a subs...
Lew AM, Hosking CS, Studdert MJ.Tests for T- and B-cell quantitation and immune function were developed, and their application in the diagnosis of primary severe combined immunodeficiency disease (CID) in Arabian foals was investigated. Foals with CID had severe lymphopenia and had small or zero numbers of B cells, as shown by immunofluorescence of surface immunoglobulin (Ig), erythrocyte-antibody-complement rosetting, and staphylococcal protein A rosetting. Serum IgM was undetectable in four CID foals 25 to 71 days old. Demonstrable antibody responses were not elicited in CID foals by phage phi X-174, a potent antigen in no...
Osborne C.A 7-year-old Arabian gelding was presented with a 9-month history of progressive patches of nonpruritic scaling, crusting, alopecia, and leukoderma of the periocular areas and muzzle, becoming generalized over time. Sebaceous adenitis was diagnosed on histopathologic examination. Lesions resolved without treatment, coinciding with regression of a sarcoid on the neck. Un cheval Arabe castré âgé de 7 ans a été présenté pour une histoire de 9 mois de plaques de desquamation, de croutes, d’alopécie et de leucodermie sur les régions périoculaire et sur le nez, devenant généralisées ...
Anjos DH, Rodrigues ML.The structure of the community of Strongylidae nematodes in the dorsal colon of naturally infected horses from the metropolitan region of Rio de Janeiro State was evaluated in 33 samples. Twenty-three species were found: Cylicostephanus longibursatus, Cylicostephanus goldi, Cylicocyclus nassatus and Cyathostomum tetracanthum were the central ones; Cylicostephanus minutus, Cylicostephanus calicatus, Cylicocyclus leptostomus, Cylicodontophorus bicoronatus and Parapoteriostomum euproctus were secondary, and there were 14 satellite species. The community was considered stable, with positive associ...
Watts AE, Fubini SL.This report describes a modification of the parainguinal approach for removal of cystic calculi: a ventral midline laparotomy-guided parainguinal laparocystotomy. The ventral midline approach to the abdomen is rapid and routinely used by equine surgeons. With an arm introduced to the abdomen via the ventral midline, the surgeon is able to select the ideal parainguinal laparotomy incision location that allows bladder exteriorisation with the minimum amount of tension. Because the surgeon's hand is introduced via the ventral midline incision, the parainguinal incision can be sized to just allow ...
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.
Barber SM.A case of uterine torsion in a mare with colic is described in which an early diagnosis was made and the torsion successfully reduced through a standing laparotomy with survival of both the mare and the foal. This case is used to stress the importance of thorough examination of all pregnant mares with colic in order to differentiate uterine torsion from other causes of abdominal pain, thereby avoiding delay in surgical correction and reducing the risk of fetal and/or maternal death. The advantages of the standing laparotomy are presented in support of this method of treatment of torsion of the...