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.
Yovich JV, McIlwraith CW, Stashak TS.Osteochondritis dissecans of the sagittal ridge of the third metacarpal and metatarsal bones was diagnosed in 8 horses during an 18-month period. Seven of the horses were less than or equal to 2 1/2 years old. Synovial distention of the affected fetlock joints and a pain response to fetlock flexion were typical findings. Lameness predominated in 1 limb at a trot, although fetlock flexion frequently elicited lameness in other affected limbs. Radiography revealed bony lesions (flattening, erosion, or fragmentation) of the sagittal ridge in at least 2 fetlock joints in all horses. The onset of si...
Selim SA, Soliman R, Osman K, Padhye AA, Ajello L.Isolation of Histoplasma farciminosum from five horses, showing typical signs of histoplasmosis farciminosi (epizootic lymphangitis) was successfully attempted. The mycelial form of H. farciminosum was isolated on Sabouraud dextrose agar enriched with 2.5% glycerol, brain heart infusion (BHI) agar enriched with 10% horse blood and PPLO dextrose glycerol agar. The last medium proved to be the most effective, both for primary isolation and subculturing of the fungus. It was found that on primary isolation, the lag phase of the mycelial form of the fungus was relatively long, involving 4-8 weeks ...
Van der Lugt JJ, Coetzer JA, Jordaan P, Marlow CH.Tyzzer's disease was diagnosed histologically in two foals, a 4-week-old Thoroughbred cross and a 6-week-old Arabian foal. Clinically both foals were in good health prior to a short illness lasting only a few hours. The liver lesions in both foals were characterized microscopically by multiple foci of necrosis. Variable numbers of elongated slender intracytoplasmic bacilli resembling Bacillus piliformis were demonstrated within hepatocytes bordering the necrotic foci.
Duncan SG, Meyers KM, Reed SM, Grant B.This experiment was designed to establish a model for the study of gastrointestinal disturbances as a result of prolonged endotoxin uptake in the horse. The hepatic portal vein of 7 horses was catheterized (through flank incisions) to give chronic hepatic portal infusions of lipopolysaccharide (LPS, endotoxin). Lipopolysaccharide was infused at a rate of 1 microgram/kg of body weight/hr for 24 hours. Two of the horses were infused with saline solution for 12 hours before LPS infusions were given. Lipopolysaccharide was shown to affect behavior and hematologic and coagulation values. The 1st ho...
McClure JJ, Addison JD, Miller RI.Oral candidiasis and bacterial septicemia were diagnosed in 8 foals that had laboratory and/or pathologic evidence of immunodeficiency. Two foals suffered solely from complete failure of passive transfer of colostal immunoglobulins. Six foals had evidence of immune defects but did not meet the criteria for diagnosis of any of the currently recognized primary equine immunodeficiency syndromes. All six of these foals died or were euthanatized due to bacterial infections. One foal with failure of passive transfer recovered and the other died of a mesenteric torsion before the effect of treatment ...
Lunn DP, Peel JE.A five-year-old standardbred mare suffered a cervical oesophageal rupture subsequent to a kick. Marked cellulitis and extensive soft tissue damage resulted. Treatment consisted of creating an oesophageal fistula, local debridement and systemic antibiotics. The mare made a long but successful recovery. Treatment of oesophageal rupture in the horse is discussed.
Sohrabi Haghdoost I, Zakarian B.THE results of a 20 year retrospective study of the tumours diagnosed in all equine cases referred to the Faculty of Veterinary Medicine, University of Teheran, for surgical treatment or post mortem examination are reported here.
Courtney CH, Asquith RL.ALTHOUGH the seasonal transmission of equine cyathostomes is well documented in cool climates (Ogbourne 1978),
less is known about their transmission in warm climates.
Australian studies have suggested that these parasites do not
survive well during the long, hot summers of the humid
subtropics (English 1979a.b). Development of egg to third
stage larva (L3) was rapid during the summer but the
percentage of larvae that survived to ascend herbage was very
low. In contrast, larvae survived for longer periods during the
cooler months and the highest L3 populations were observed
during spr...
Foil L, Stage D, Adams WV, Issel CJ.The occurrence of tabanid feeding between mares and foals was observed. When mares and foals were observed freely moving within a pasture situation, foals had 2.43% (4 flies in 77 observations vs 297 flies in 139 observations) of the tabanid feeding occurrences of the mares. This difference in tabanid burden varied due to herd size, herd location, and tabanid species. Lower tabanid burden of foals was indicated as a practical protective mechanism against pathogenic agents mechanically transmitted by tabanids, such as equine infectious anemia virus.
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 ...
Brown CM, Slocombe RF, Derksen FJ.A method of fiberoptic gastroduodenoscopy and biopsy was developed for use in large horses. A 275 cm X 13.5 mm fiberendoscope was used to examine the stomach and proximal portion of the duodenum. Food was withheld for 24 to 48 hours before examination. In more than 50 horses, gastric and duodenal structures were easily visualized. A variety of lesions was detected, including parasitic lesions, gastric ulcers, gastric neoplasia, and pyloric stenosis. Mucosal biopsy specimens were obtained in selected cases.
Issel CJ, Adams WV, Foil LD.Progeny of a band of horses, positive by the agar-gel immunodiffusion (AGID) test for equine infectious anemia (EIA) antibody, were observed through their weaning over a 4-year period. Sentinels (AGID test-negative) were allowed to mingle with EIA-infected mares and their foals in pasture situations in an area with high populations of potential vectors. Of 27 adult sentinels, 8 (30%) seroconverted in annual rates ranging from 0% to 75%. In contrast, only 2 of 31 (6%) foals weaned became infected. Difference in infection rates between adult sentinels and foals was significant (chi 2, P less tha...
Dunsmore JD.An attempt was made to control or eliminate Strongylus vulgaris from a closed group of three horses at pasture near Perth, Western Australia, by dosing with ivermectin on four occasions during the time of year when it was believed that environmental conditions would eliminate all the non-parasitic stages of that species. At necropsy, five months after the last dose of anthelmintic and after continually grazing the same pastures, no S vulgaris or arterial lesions were found in those horses and S edentatus, Draschia megastoma and Habronema species were also almost completely eliminated.
Davies JV, Gerring EL.Small intestinal ischaemia is a cause of pain in man and horses. Occlusion of the vascular supply to Thiry loops in experimental ponies caused severe discomfort and loss of motility within a few minutes but these effects could not be reproduced by a similar procedure in intact gut preparations. However, embolisation of the mural vascular network produced ischaemia of the small intestine of anaesthetised ponies which led to a cessation of motility in the affected segments, though unaffected segments became hypermotile with a characteristic motility pattern. These results suggest the need for re...
Duncan ID, Brook D.Four two-year-old Thoroughbreds suffered an acute gastrointestinal illness shortly after dosing with mineral oil which was thought to have been contaminated with an organophosphate compound. Three weeks later all four were noted to be dyspnoeic and endoscopic examination showed that they had developed bilateral laryngeal paralysis. Two of the horses died during severe bouts of dyspnoea six and eight months later and the third was killed shortly thereafter. Examination of the left and right recurrent laryngeal nerves from these horses showed a severe loss of myelinated fibres distally, especial...
Widders PR, Stokes CR, Newby TJ, Bourne FJ.This study identifies nonimmune binding of equine immunoglobulin by the causative organism of contagious equine metritis. Immunoglobulin binding to the bacterium was strongest for immunoglobulin G (IgG) and less for IgM; IgA was not bound. Binding of equine IgG was inhibited by human IgG, but not by IgG of domestic animals. Immunoglobulin binding by the bacterium appeared to be directed towards an epitope in the hinge region of the immunoglobulin molecule.
Kozlov DP.The problem of dissimilation of larvae of strongylates of ruminants in pasture biocoenosis is discussed. A new form of their migration in horizontal direction on the basis of negative geotaxis is suggested. As a result of alternation of vertical migration of larvae on the tilting leaves of the grass and their subsequent washing off with rain or dew down on the ground proceeds their distribution on the pasture. The description of corresponding experiments is given.
Breider MA, Kiely RG, Edwards JF.A generalized debilitating disease in a horse was believed to be related to hypersensitivity to migrating strongyle larvae. The clinical signs included weight loss, diarrhea, and ulcers on all 4 coronary bands. The mare's condition deteriorated rapidly, so the mare was euthanatized and necropsied. The major histopathologic findings were chronic multifocal eosinophilic pancreatitis, hepatic portal fibrosis, biliary hyperplasia, and chronic ulcerative eosinophilic colitis. This case was similar to previously reported cases of chronic eosinophilic gastroenteritis in horses. Although the etiologic...
of surveillance testing, April to June 2017International disease occurrence in the second quarter of 2017These are among matters discussed in the most recent quarterly equine disease surveillance report, prepared by Defra, the Animal Health Trust and the British Equine Veterinary Association.
Loynachan AT.Pulmonary malformations are rare equine congenital anomalies. Over a 3-year timeframe, three cases of left sided pulmonary agenesis were diagnosed in perinatal foals. All three cases were associated with concurrent ipsilateral diaphragmatic herniation and hypoplasia of the right lung lobe. All three foals died immediately following parturition due to perinatal asphyxia associated with the congenital malformations. To the author's knowledge, this is the first report of pulmonary agenesis in the horse.