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.
Vitums A, Bayly WM.Three Arabian males foals were presented with cyanosis, heart murmur, and exercise intolerance, Results of clinical evaluation suggested a tentative diagnosis of ventricular septal defect in conjunction with malformations of the great arteries. Each foal had a poor prognosis and was killed at the owners' requests. At necropsy, the malformed hearts of the three foals were virtually identical. Each heart had a large defect in the upper interventricular septum. The aorta originated from the hypertrophied right ventricle and partially overrode the ventricular septal defect. The aortic ostium was g...
Power HT, McEvoy EO, Manning TO.A 4-month-old foal was examined because of generalized exfoliative dermatitis, with thick scales, extensive crusting, and oozing of serum. A diagnosis of pemphigus foliaceus was made by histologic and immunopathologic examinations of skin biopsy specimens. The foal was treated with a gold compound, aurothioglucose (1 mg/kg once weekly for 14 weeks). For the initial 5 weeks, high-dose glucocorticoid treatments also was used. The skin disorder resolved entirely after 12 weeks of treatment.
Roberts MC, Kelly WR.A four-year-old thoroughbred was presented with clinical manifestations of purpura haemorrhagica. Evidence of renal involvement consistent with glomerulopathy and nephrotic syndrome, characterised by heavy proteinuria and azotaemia, became apparent and may have been exacerbated by diuretic therapy. Autopsy revealed membrano- and mesangial proliferative glomerulonephritis and chronic pleuritis. Circulating immune complexes may have been responsible for the renal diseases and the purpura.
Issel CJ, Adams WV.A horse whose serum reacted equivocally in the agar gel immunodiffusion (AGID) test for equine infectious anemia was studied over a 3-year period. The horse remained afebrile and virus was detected in only 1 of 6 horse inoculation tests. The intensity of AGID test reactions increased temporarily following this evidence for virus. Although the AGID test reaction was equivocal and 5 of the 6 transmission attempts failed, the 1 successful transmission proved the horse was infected.
Prescott JF, Srivastava SK, deGannes R, Barnum DA.A mild form of strangles caused by an atypical Streptococcus equi was recognized on a large horse breeding farm. The organism differed from most S equi isolates by disappearance of the mucoid capsule by 24 hours of culture, leaving a matt-type colony. Typically, the clinical signs were a transient (24-48 hour) fever, profuse nasal discharge, and anorexia. In about half the affected animals, there was moderate mandibular lymph node enlargement, and these glands usually ruptured or were drained. The use of a passive hemagglutination antibody test showed that subclinical infection was widespread ...
Divers TJ, George LW, George JW.Signs of acute hemolytic anemia developed in 4 adult horses from 2 Georgia farms 3 to 4 days after the ingestion of wilted leaves from cut red maple trees (Acer rubrum). Clinical findings included weakness, polypnea, tachycardia, depression, icterus, cyanosis, and brownish discoloration of the blood and urine. Blood changes included methemoglobinemia, free plasma hemoglobin, decreased pcv, and Heinz bodies in erythrocytes. These findings plus hemoglobinuria suggested intravascular hemolysis. Three of the 4 horses diet 5 to 7 days after ingestion of the leaves. Gross pathologic changes included...
Allen PZ, Glode M, Schneerson R, Robbins JB.Hyperimmune horse serum from a single animal (horse 46) immunized with group B (strain B-11) meningococcal vaccine provides a standardized, readily available diagnostic reagent used in primary isolation medium and for serogrouping of meningococci. Identification of the heavy-chain isotypes of specific anticapsular polysaccharide and anti-lipopolysaccharide isolated from horse 46 serum revealed a differential distribution in the occurrence of immunoglobulin classes. Meningococcal anticapsular antibodies of horse 46 serum were restricted predominately to the immunoglobulin M (IgM) class, with on...
Mutimer MD, Prescott JF, Woolcock JB.One hundred strains of Rhodococcus equi from various animal species and sources in Australia were examined for capsular serotype. Eighty-four of the strains fell into the existing 7 serotypes, and just under half of the strains belonged to serotype 1. Isolates from the intestines and faeces of horses, cattle, pigs and other species, and from soil, were found to belong to the same serotypes as those recovered from the lungs of foals with R. equi pneumonia. There was no clear relationships between capsular serotype and source of origin of the isolates.
Hultgren BD.The congenital absence of myenteric ganglia in the terminal portion of the ileum, cecum, and entire colon of white foals with overo spotted parents was reported. Males as well as females were affected. The foals were generally normal at birth but did not defecate. Signs of colic were noticed between 5 and 24 hours after birth, with death occurring at 23 to 132 hours.
London WT, Levitt NH, Altshuler G, Curfman BL, Kent SG, Palmer AE, Sever JL, Houff SA.Fetal rhesus monkeys were inoculated intracerebrally with an attenuated strain of western equine encephalitis virus. All animals developed microcephaly. Twelve of sixteen monkeys developed ex vacuo hydrocephalus. All virus inoculated fetuses developed WEE virus antibody. Virus could not be recovered at the time of delivery. Monkeys with the highest WEE antibody titers showed the greatest degree of hydrocephalus.
Dill SG, Simoncini DC, Bolton GR, Rendano VT, Crissman JW, King JM, Tennant BC.During a period of 18 months, between July 1978 and January 1980, 4 adult horses were referred to the New York State College of Veterinary Medicine with evidence of congestive heart failure. Characteristic clinical abnormalities included marked muffling of heart sounds, tachycardia, jugular vein distention, and peripheral edema. Treatment with antibiotics, diuretics, and anti-inflammatory drugs was unsuccessful, and all four died or were euthanatized and necropsied. At necropsy, there was marked distention of the pericardial sac with fluid, and thick layers of fibrin were deposited uniformly o...
Tzipori S, Makin T, Smith M, Krautil F.Colostrum-deprived, colostrum-fed or suckling foals were orally inoculated with foal rotavirus and enterotoxigenic Escherichia coli derived from a calf. Neither agent given alone caused diarrhoea in foals aged 1 or 2 days, although with rotavirus, 2 of the 3 inoculated foals became depressed 3 days after inoculation and all 3 were excreting rotavirus in the faeces. Inoculation of both agents induced diarrhoea in colostrum-deprived, colostrum-fed or suckling foals aged up to 16 days. There was an apparent age-related resistance to diarrhoea which developed between 2 and 3 weeks of age. It was r...
Wagner AE, Bennett DG.Eighteen clinically normal horses were used to study the characteristics of normal thoracic fluid. Thoracic fluid was obtained from each horse and was found to be similar to equine abdominal fluid. Total leukocytes averaged 3994/ul, total protein 1.8 g/dl, and specific gravity 1.015. Analysis of thoracic fluid from 16 horses with clinical signs of thoracic disease showed abnormalities in every case. Thoracic fluid analysis alone determined a specific diagnosis in 50% of the cases.
Robinson RC.Soil samples were collected from 6 horse breeding establishments in California and cultured for Corynebacterium equi. Only 3 of the farms had a history of the occurrence of pneumonia caused by C. equi. One farm had experienced an outbreak in 5 out of 6 foals just before soil sampling. Soil isolates were identified as C. equi on the basis of physical and biochemical characteristics found to be consistent with isolates of equine origin. C. equi was found in many soil samples within endemic areas where greatest concentrations were obtained in places accessible to horses. On non-endemic farms, onl...
Kotoński B.The purification of alpha-1,4-1,4-glucosyltransferase from the equine serum is presented. Ion-exchange chromatography on DE-11, DE-32 and CM-32 celluloses was applied in the successive steps of isolation. Gel-filtration on Bio-Gel P-200 was the last step of purification; it gave the protein which was homogeneous on disc polyacrylamide gel electrophoresis. The purification degree was of the order 2100 at about 40% yield.
Goto H, Shimizu K, Taya Y, Noda H, Tokunaga T.The antibody responses to equine influenza viruses were investigated during a postepizootic period of the disease. Serum samples were collected from a total of 128 horses on three occasions during the years 1967-77. No significant increase of hemagglutination-inhibition antibody titers to subtypes 1 and 2 of equine influenza virus were detected in any of the sera tested. The maternal hemagglutination-inhibition antibody titers of foals decreased over a four month interval. A marked increase of the titers was recognized in only the equine influenza virus vaccinated horses. These findings sugges...
Patel JR, Edington N, Mumford JA.Subtype-1 isolates of Equine herpesvirus-1 (EHV-1) from a quadriplegic horse and from an aborted foetus were compared with each other and with a subtype-2 respiratory isolate. All 3 isolates were detected in the epithelium and macrophages of the respiratory tract. Both the paresis and foetal subtype-1 isolates replicated in the epithelium of the ileum and this correlated with the recovery of virus from faeces in vivo. The paresis subtype-1 isolate also had a predelection for vascular endothelial cells, particularly in the nasal mucosa, but also in the lungs, central nervous system, adrenal and...
Millar R, Francis J.Day (1939) recorded 95% fertility in wild
ponies, but in heavy horses it was only 52%
and in thoroughbreds 68%. Variation of fertility was stated by Anderson (1922) was not due
to disease or physiological malfunction, but to
highly artificial methods of mating. In New
Zealand, Bain (1948) recorded the fertility of
mares in 1944 as 61%. MahaiIey (1950) made
a survey in Western Australia and found fertility
rates which varied from 17% to 50% before
veterinary assistance was obtained.
An article in the British Racehorse (Anon
1949) revealed no evidence of any progress in
the control o...
Wijnberg ID, Vink-Nooteboom M, Sloet van Oldruitenborgh-Oosterbaan MM.A 7-year-old Friesian gelding was referred to the Department of Large Animal Medicine and Nutrition of the Faculty of Veterinary Medicine because of an inadequate response to treatment for vague symptoms of colic. An extensive physical examination showed there to be circulatory problems, with right-sided decompensation. Heart sounds were muffled on both sides of the thorax, and ECG showed a low voltage and variable amplitude of the QRS complex. Further investigations indicated idiopathic pericardial effusion. Pericardiocentesis was performed and supportive therapy started. Three weeks later th...