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.
Widders PR, Warner S, Huntington PJ.Normal mares were immunised by the intramuscular and intrauterine administration of an antigen with adjuvant and they and unimmunised control mares were later challenged by the intrauterine instillation of pathogenic Streptococcus zooepidemicus; the response of all the mares was monitored clinically and bacteriologically for seven days. Significantly fewer S zooepidemicus were present in cervical swabs taken from the immunised mares than from the control mares (P < 0.01) and the degree of inflammation in the genital tract of the immunised mares was also significantly less (P < 0.001). Th...
Adeyefa CA, Hamblin C.Equine sera collected from 10 widely separated regions throughout Nigeria were tested for antibodies against African horse sickness viruses (AHSV) using a competitive enzyme-linked immunosorbent assay (ELISA). The animals sampled included imported, exotic horses, indigenous and locally cross-bred (local) horses and African donkeys. A high percentage of the sera (79.8%) were positive, confirming the continued prevalence of AHSV antibodies in Nigerian horses and donkeys.
Miyazawa T, Matsuda M, Isayama Y, Samata T, Ishida Y, Ogawa S, Takei K, Honda M, Kamada M.Profiles of the genomic DNA of 104 strains of T. equigenitalis isolated from brood mares with contagious equine metritis in Hokkaido during the breeding seasons from 1980 to 1993, as well as those of five strains (SS28, EQ56, EQ59, EQ70 and HH139) previously isolated in Japan were examined after restriction digestion and crossed-field gel electrophoresis. These profiles were essentially identical to each other and the various isolates and strains appeared to have a common genotype, designated 'genotype J', with respect to two restriction enzymes, ApaI and NotI. These results suggest a common s...
Manning M, Dubielzig R, McGuirk S.A foal with azotemia, acidemia, and electrolyte abnormalities was diagnosed with uroperitoneum. The foal was anesthetized with isoflurane, and throughout the 4 hours of anesthesia and abdominal surgery, its mean arterial pressure ranged between 45 and 65 mm Hg. The foal developed a myopathy postoperatively and died 24 hours after surgery.
Rossdale PD, Ousey JC, McGladdery AJ, Prandi S, Holdstock N, Grainger L, Houghton E.Plasma progestagen concentrations were measured daily by radioimmunoassay (RIA) in 35 sick foals for the duration of their illness. The foals were divided into three groups on the basis of time to stand after birth. Foals were given intensive care treatment according to the severity of their illness. Plasma and urine concentrations of pregnenolone (P5) and pregnenediol (P5 beta beta) were measured by gas chromatography--mass spectrometry; plasma cortisol concentrations were measured by RIA and the foals' renal and respiratory status were assessed by creatinine clearance ratios and arterial oxy...
Egri B, Sárközy P, Bánhidy G.From 14 to 17 April 1990 and from 12 to 21 May 1993 a total of 136 Caucasian (Donish, Karabakh, Kabardin, local halfbred) and 26 thoroughbred stud-horses were examined for ectoparasites in studs of Stawropol County, Russia. A total of 4054 botfly larvae were identified from 9700 faecal samples collected during a period of 3-4 days after oral treatment with Eqvalan (MSD), Strongid Plus (Pfizer) and Vermitan Plus (Sanofi-Chinoin). The species distribution was: Gasterophilus intestinalis 84.53%, G. nasalis 10.41%, G. haemorrhoidalis 3.62%, G. inermis 1.41%. Gasterophilus nasalis and G. inermis ha...
Edwards RB, Fubini SL.Five Holstein calves and two foals with omphalophlebitis were treated by surgical marsupialization of the umbilical vein remnant because complete resection of the infected tract was not possible. The infected umbilical stalk was resected, and the umbilical vein remnant was marsupialized in a one-stage procedure by suturing it into the abdominal wall lateral to the abdominal incision. Antimicrobial drugs were administered, and the marsupialized tract was irrigated until closure by second intention healing. Cellulitis associated with the marsupialization site occurred in two calves but resolved ...
Ficorilli N, Studdert MJ, Crabb BS.The nucleotide sequence of the glycoprotein G (gG) homologue of asinine herpesvirus 3 (AHV3), a respiratory alphaherpesvirus of donkeys, was determined. The AHV3 gG gene consists of 1233 base pairs (bp) and codes for a predicted protein of 411 amino acids. This is identical in size to the equine herpesvirus 1 (EHV1) gG gene and 6 amino acids longer than the equine herpesvirus 4 (EHV4) gG gene. The predicted amino acid sequence of AHV3 gG has characteristics of a class 1 membrane protein. The amino acid sequence of AHV3 gG shows 92% and 60% identity to EHV1 gG and EHV4 gG respectively. Two regi...
Sekiguchi K, Sugita S, Fukunaga Y, Kondo T, Wada R, Kamada M, Yamaguchi S.A polymerase chain reaction (PCR) based assay capable of detecting and differentiating seven strains of equine arteritis virus (EAV) from around the world was developed. The primers for the PCR were chosen from the ORF6 gene encoding the unglycosylated membrane protein (M). Viral RNA from cell culture fluids infected with each of the seven EAV strains and RNA from the live vaccine, Arvac, was detected by PCR using four sets of primers. The sensitivity of detection was increased from 100 to 1,000 times by performing nested PCR enabling the detection of RNA at a level of 0.5-5 PFU. Differentiati...
Boosinger TR, Brendemuehl JP, Bransby DL, Wright JC, Kemppainen RJ, Kee DD.Newborn foals of mares grazing on Acremonium coenophialum-infected fescue pasture throughout gestation or from gestation day 300 to parturition had increased gestation duration and decreased serum triiodothyronine concentration. Pregnant mares were allotted to 4 treatments: grazing continuously on endophyte-free (E-) fescue, grazing continuously on endophyte-infected (E+) fescue, grazing on E+ fescue from gestation day 300 to parturition, and grazing on E+ fescue from conception to gestation day 300. Morphometric studies indicated that foals born to mares exposed to endophyte late in gestation...
Crabb BS, MacPherson CM, Reubel GH, Browning GF, Studdert MJ, Drummer HE.We describe a type-specific ELISA, which distinguishes antibody to equine herpesvirus 4 (EHV4; equine rhinopneumonitis) and EHV1 (equine abortion virus) thereby identifying horses that have been infected with either or both of these antigenically related viruses. The antigens used are parts of the EHV4 and EHV1 glycoprotein G (gG) homologues expressed in E. coli as fusion proteins [Crabb and Studdert, 1993: J Virol 67: 6332-6338). The expressed proteins comprise corresponding regions of the gG molecules that are highly divergent and encompass strong, typespecific epitopes. Plasma samples from ...
Guthrie AJ, Beadle RE, Bateman RD, White CE.The purpose of this study was to characterize the normal equine tidal breathing flow-volume loop (TBFVL). The study was performed using 18 healthy Thoroughbred horses. TBFVLs constructed from data collected from resting horses had a typical biphasic inspiratory and expiratory phase. The interindividual variability of the indices used to describe TBFVLs was in the range 16-32%, which is comparable to the variability of other measures of equine pulmonary mechanics. The large variability of these data probably limits the value of resting TBFVL indices for detecting subclinical respiratory conditi...
Madsen M, Christensen P.Semen samples were collected from 21 Danish Warmblood stallions by the Colorado artificial vagina (Colorado AV, 14 samples) or by the Missouri artificial vagina (Missouri AV, 7 samples). The semen was examined bacteriologically by direct plating (DP) on blood agar plates, and by plating of semen swabs stored in Stuart's transport media (TM) at 4 degrees C for 1-4 days. No significant differences were observed between results obtained by DP and cultures of identical TM samples. Of the 21 samples examined, only 1 TM (4.8%) and 2 DP samples (9.5%) were sterile, while the rest yielded a predominan...
Allen G, Yeargan M, Costa LR, Cross R.An experimental system that permits sensitive and reproducible detection of equine herpesvirus 1 (EHV-1)-specific cytotoxic T-lymphocyte (CTL) activity in the horse was developed. Peripheral blood mononuclear cells (PBMC) collected from immune horses were restimulated in vitro by culture with live EHV-1. Cytotoxic activity against virus-infected, pokeweed mitogen-stimulated lymphoblast targets was assessed in a 4-h 51Cr release assay. The optimal conditions for in vitro stimulation of equine memory CTLs and for preparation of EHV-1-infected target cells expressing viral antigens were systemati...
Oelrichs PB, Calanasan CA, MacLeod JK, Seawright AA, Ng JC.Regular ingestion of Eupatorium adenophorum [Ageratina adenophora (Spreng.)] or Crofton weed causes chronic pulmonary disease in horses mainly in Australia, New Zealand, and the Himalayas. The disease is characterized by pulmonary interstitial fibrosis, emphysema, alveolar epithelisation and reduced tolerance to exercise. Horses apparently are the only animals affected and there are numerous reports of farms losing all their horses. The disorder was produced experimentally in horse feeding trials, and it was shown that characteristic lesions occurred in the lungs. In studies with laboratory an...
Barnard BJ, Bengis R, Keet D, Dekker EH.The viraemic period of African horsesickness is significantly longer in experimentally infected zebra than in horses. The virus could be isolated 40 d post-infection from blood and 48 d post-infection from spleen. The introduction of zebra into African horsesickness-free countries should therefore be considered carefully, and preferably be restricted to serologically negative zebra.
Holbrook TC, Moore JN.Endotoxemia and septicemia are encountered frequently in equine veterinary practice. The deleterious effects of endotoxin are related to the severity of the response of the host's inflammatory system. Consequently, it is imperative that appropriate steps be taken to identify animals at risk of developing endotoxemia or septicemia, and to initiate treatments that will reduce the inflammatory response. This article discusses the anti-inflammatory and immune support of horses and foals with endotoxemia and septicemia.
Allen DA, Schertel ER.Shock has been described and defined by the inciting cause. This method of categorization does little to clarify common pathophysiologic changes known to occur regardless of the etiology. Each type of shock involves different stages that are determined by the inciting cause, its duration, severity of the initial result, susceptibility of the patient, and adequacy of treatment.
Khoury C, Manilla G, Maroli M.The following 13 species of ticks, belonging to Ixodidae family, were recorded in Italy on horse (Equus caballus) since 1931: Ixodes ricinus, I. gibbosus, Haemaphysalis inermis, H. parva, H. punctata, H. sulcata, Dermacentor marginatus, Rhipicephalus sanguineus, Rh. bursa, Rh. turanicus, Hyalomma marginatum, Hy. detritum, Boophilus annulatus. The regional distribution and the role of the species in the transmission of pathogens are reported.
Brumbaugh GW.In emergency conditions, antimicrobial treatment is subordinate to truly life-supporting measures. Antimicrobial treatment should be formulated rationally for each patient and should not simply be a matter of following a recipe. This article presents principles for guiding rational therapeutic decision-making and examples of conditions in which those principles can be applied.
Rebhun WC.Most ocular and orbital injuries or acute ocular inflammation in horses result in similar signs of adnexal swelling, photophobia, blepharospasm, and lacrimation. It is hoped that detailed examination and the suggestions in this article will enable veterinarians attending horses having ocular emergencies to arrive at a correct diagnosis and appropriate therapy.
Hubbell JA, Muir WW.Clinical examination of the equine patient with acute abdominal pain should identify the affected body system and yield a provisional diagnosis. Determination of signalment, history, physical examination, and basic laboratory tests should assist in classification of the gastrointestinal disorder and direct the therapeutic plan. Determination of the definitive diagnosis of abdominal pain based on clinical examination is not crucial. For a successful outcome, efforts should be directed toward early recognition of the need for surgery and treatment of cardiovascular compromise in horses with seve...
Stein RS, Means RT, Krantz SB, Flexner JM, Greer JP.The authors evaluated antilymphocyte serum prepared in rabbits (ALS-R) as an alternative to antilymphocyte serum prepared in horses (ALG-H) in the therapy of aplastic anemia. Between 1980 and 1993, 57 evaluable patients received ALS-R and prednisone +/- cyclosporine +/- androgens. Standard response criteria were used and patients were evaluated at 3 months from the start of therapy. Median age was 43 years. Disease was present for up to 2 months in 24 patients, 2-5 months in 14 patients, and 6 months or more in 19 patients. Disease was severe in 30 patients and moderate in 27. Responses occurr...
Tomizawa N, Nishimura R, Sasaki N, Kadosawa T, Senba H, Hara S, Takeuchi A.Cervical myelography and survey radiography was performed on 12 light breed wobbling foals and a new radiographic measurement method was applied for more accurate diagnosis of cervical vertebral instability. Ratios of stenosis of the spinal canal on survey radiography and myelography using relative values in an individual foal were defined on radiograms of lateral flexed position of mid-cervical region, and coincidence between the ratios and histopathological lesions in the cervical spinal cord was investigated. Five of 6 foals had ratios of stenosis on myelography more than 40% at the interve...
Connor RJ, Kawaoka Y, Webster RG, Paulson JC.The receptor specificity of 56 H2 and H3 influenza virus isolates from various animal species has been determined to test the relevance of receptor specificity to the ecology of influenza virus. The results show that the receptor specificity of both H2 and H3 isolates evaluated for sialic acid linkage specificity and inhibition of hemagglutination by horse serum correlates with the species of origin, as postulated earlier for H3 strains based on a limited survey of five human, three avian, and one equine strain. Elucidation of the amino acid sequence of several human H2 receptor variants and a...
Rhinosporidiosis is caused by Rhinosporidium seeberi, a parasitic organism of the family Rhinosporideacea family, class Micomycetozoa. The disease is endemic in India; however, some cases were reported in Europe, Africa, North America, and South America. The aim of the present study is to report three cases of rhinosporidiosis in wild horses in different cities of Buenos Aires province, Argentina. We confirm the presence of R. seeberi in the analyzed samples using histopathological and PCR sequencing techniques.
Binhazim AA, Harmon BG, Roberson EL, Boerner M.During routine necropsy of a 28-year-old horse with intestinal volvulus, numerous hydatid cysts were discovered in the liver. Viable protoscolices of Echinococcus granulosus were obtained from the cyst. As a 4-year-old, this horse had been imported from an area that is enzootic for equine hydatidosis.
Brownlie SE.The Chiltern Box is a small electrocardiograph designed for home monitoring of human patients. Its veterinary application has been investigated in the dog, the cat and the horse. It has been useful in the diagnosis of previously undiagnosed dysrhythmias in dogs showing signs of exercise intolerance and syncope.
Gardner DG.Previously published cases of ameloblastoma in the horse are reviewed in detail for their acceptability as examples of that tumor; an additional one is described. So far, this rare equine lesion has been shown to have two histologic patterns. The first consists of islands and sheets of epithelium that exhibit the basal cell characteristics of ameloblastoma; the central cells comprise stellate reticulum. The second exhibits these basal cell features less markedly and the central cells are spindle-shaped and closely packed. The biologic behavior of the equine ameloblastoma is thought to be the s...
Eroksuz H, Eroksuz Y, Ozer H, Ceribasi AO, Yaman I, Ilhan N.Naturally occurring goiter cases are described in 2 newborn Arabian foals whose mares were supplemented with excess iodine during the final 24 w of the pregnancy. Six nursing foals and 2 mares were also affected clinically with thyroid hypertrophy. At least 12 times the maximum tolerable level of iodine supplementation was given, as the daily iodine intake for each mare was 299 mg. The prevalence of goiter cases was 2 and 9% in the mares and foals, respectively.
Miller PJ, Holmes JR.Observations on seven cases of mitral insufficiency are described. Three of the horses had recent histories of cardiac failure and formed a separate group in which there were marked haemodynamic changes which varied in relation to heart rate but were associated with pulmonary hypertension, elevated right ventricular pressure and low peak left ventricular pressure. In the other four horses the heart appeared to be compensating at rest but to be unable to cope with severe exertion. On auscultation, a widespread pansystolic murmur and a prominent third heart sound were characteristic of the left ...
Bemis DA, Bryant MJ, Kania SA, Newman SJ.Based on the scarcity of reports in veterinary medicine literature, it appears that Arcanobacterium spp. are rarely isolated from horses. Recently, a single isolate from vaginal discharge in a mare was characterized as a new species, Arcanobacterium hippocoleae. The present report describes a case of necrosuppurative placentitis and stillbirth in an American Quarterhorse mare. Numerous colonies of irregular, Gram-positive, rod-shaped bacteria were observed by histological examination within fibrin lattice associated with placental lesions. Arcanobacterium hippocoleae was isolated in large numb...
Migliorisi A, Hart K, Vaughn S, Austin S, Aldridge B, Wilkins P.To describe ascorbic acid (AA) concentrations, plasma antioxidant capacity (PAC) and markers of oxidative stress, as measured by derivatives of reactive oxygen metabolites (dROMs), in healthy foals at birth and during the first month of life. Methods: Venous blood samples were collected from healthy Standardbred (n = 13) and Quarter Horse (n = 10) foals. Plasma AA, PAC, and dROMs were assessed at 3 to 12 hours, 3 days, and 1, 2, and 4 weeks of age. Methods: AA was measured via high-performance liquid chromatography. PAC and dROMs were measured with a free radical analytical system. Comparisons...
Adeppa J, Ananda KJ, Krishna Murthy CM, Satheesha GM.A study was conducted to ascertain the incidence of gastrointestinal parasites in horses of Shimoga region, to generate the data regarding status of parasitic infections of equines in Karnataka state due to paucity of information. A total of 100 fresh fecal samples of equines were collected and examined by direct and sedimentation method for the detection of parasitic egg/ova. Among 100 samples examined, 84 (84.0 %) were found positive for various gastrointestinal helminths. Out of 84 positive cases, 44 (52.38 %) were found positive for Strongylus spp. eggs, 09 (10.71 %) showed Parascaris e...
Taylor FG, Wotton PR, Hillyer MH, Barr FJ, Lucke VM.Clinical examination of a four-and-a-half-month old foal revealed evidence of progressive heart failure associated with an atrial septal defect and atrial fibrillation. Atrial septal defects are rarely reported in foals and the foal's growth, development and demeanour were normal until a sudden onset of lethargic behaviour. The value of B-mode echocardiography in identifying the congenital lesion is indicated.
Irfan M.Studies have been made on the effect of storage and temperature on factor V in animals and a method for its assay is described. There was a decrease of the factor with age in oxalated plasma of cattle, horses, sheep, dogs, rabbits and one elephant. This deterioration was very rapid in plasma kept at 37C. as compared with that stored at 4C. Rabbit plasma had the highest concentration of factor V followed by dogs, horses, cattle and sheep. Mixing various dilutions of aged plasma kept at 4C. wlth fresh plasma would enable the percentage prothrombin activity to be determined for the assay of facto...
Sasaki N, Yamada M, Morita Y, Furuoka H, Itoh M, Satoh M, Yamada H.We report a case of EMND in a heavy horse that was bred and trained in Hokkaido, Japan. Clinical symptoms included severe ataxia of all four limbs, tilted head, lethargy, and flaccid lips. Numerous axonal degenerations and swellings were observed in nuclei, mostly in the cerebellar dentate nucleus and the nucleus of the hypoglossal nerve, and in the ventral horn of the spinal cord. In the ventral horn of the spinal cord, neuronal degeneration, swelling, and/or necrosis were observed sporadically. The case was diagnosed as EMND from the clinical symptoms and pathological findings.
Yanai T, Masegi T, Ishikawa K, Sakai H, Iwasaki T, Moritomo Y, Goto N.Cerebral vascular mineralization was found in 12 (60%) of 20 3- to 10-year-old healthy horses collected at an abattoir. It was variable in degree and occurred mostly in the pallidal arteries showing two types of lesions; small globoid bodies along capillaries, and amorphous deposits in the wall of arterioles, small- or medium-sized arteries and veins. Both types were strongly positive for periodic acid-Schiff reaction, and weakly positive for von Kossa's and Berlin blue stains. Elemental analysis of the deposit revealed the presence of large amounts of aluminum, moderate amounts of phosphorus,...
Spier S, Carlson GP, Nyland TG, Snyder JR, Fischer PE.An 8-year-old gelding with a 3-month history of anorexia and weight loss was found to have a massive subcapsular splenic hematoma. At flank laparotomy, 36 L of fluid was removed from the hematoma. The horse's condition improved after drainage. Fifteen months later, the horse became depressed and febrile. A splenic abscess containing Bacteroides ruminicola and Clostridium sporogenes was found at necropsy.