Equine diseases encompass a wide range of health conditions that can affect horses, including infectious diseases, metabolic disorders, and genetic conditions. These diseases can impact the overall health, performance, and well-being of horses. Common equine diseases include equine influenza, equine herpesvirus, laminitis, and equine metabolic syndrome. Diagnosis and management of these diseases often require a combination of clinical evaluation, laboratory testing, and appropriate treatment strategies. This page gathers peer-reviewed research studies and scholarly articles that explore the etiology, pathophysiology, diagnosis, and treatment options for various equine diseases, providing valuable insights for veterinarians and researchers in the field.
Bertone AL, Sullins KE, Stashak TS, Norrdin RW.Preformed collagen gel was topically applied to cutaneous wounds of the equine dorsal fetlock (thoracic limb) and metatarsal regions to evaluate the effect on exuberant granulation tissue production and wound healing. In 6 horses and 3 ponies (less than 140 cm high at the withers and less than 365 kg), 36 standardized cutaneous limb wounds were surgically induced (4 wounds/animal); 18 wounds were treated topically with collagen gel, and 18 wounds were not treated (controls). Collagen gel was initially applied to the wound at 0, 2, or 7 days after wound formation (groups 1, 2, and 3, respective...
Schumacher J, Spano JS, Moll HD.Peritoneal fluid was collected from 15 clinically normal horses and was analyzed for nucleated cell (NC) counts and specific gravity. Six horses (controls, group 1) were subjected to abdominocentesis only, with a teat cannula, every 24 hours for 5 days. There were no marked changes in the peritoneal fluid of these horses over the 5-day period. Peritoneal fluid was collected from 6 other horses (group 2) with an 8.89-cm 18-gauge needle. The needle was then advanced until intestinal fluid was obtained. Peritoneal fluid was then collected with teat cannulas at 24-hour intervals for an additional ...
Skrabalak DS, Cuddy KK, Henion JD.Micro-liquid chromatography-mass spectrometry (micro-LC-MS) was utilized to quantitatively determine betamethasone and its major unconjugated metabolite, 6 beta-hydroxybetamethasone, in equine plasma and urine. The advantage of micro-LC-MS over conventional gas chromatography-mass spectrometry in corticosteroid determination is illustrated and the reliable, steadfast nature of micro-LC-MS is demonstrated through example.
Cummings E, James ER.Of 664 horses reported to have originated in southeastern and midwestern United States, 341 (51.4%) were positive for Onchocerca cervicalis cutaneous microfilariasis. The highest prevalence of 68.8% was recorded for horses from Virginia. Horses with the highest concentrations of microfilariae (as high as 19,770 microfilariae/mg in 1 horse) were from the Southeast (Georgia, Florida, Tennessee, and Alabama). For horses from South Carolina, the prevalence of infection was 57.1%; from the Midwest (Kentucky, Illinois, Ohio, and Indiana), 54.4%; from North Carolina, 45.5%; from Pennsylvania, 7.7%; a...
Zamora CS, Vitums A, Foreman JH, Bayly WM, Weidner JP.On the basis of clinical and laboratory examinations, a ventricular septal defect or a variant of the tetralogy of Fallot was suspected in a 3-year-old filly with a history of poor growth rate and exercise intolerance. The filly was euthanatized and found to have a 3-chambered heart (cor triloculare biatriatum). The heart had 2 normally formed atria and a large common ventricle into which the right and left atrioventricular orifices opened and from which the aorta arose. There was a small separate chamber from which the pulmonary trunk originated. This chamber communicated with the common vent...
McDonnell SM, Kenney RM, Meckley PE, Garcia MC.Sexual behavior dysfunction unaccompanied by detectable physical or endocrine abnormality is an important cause of reproductive failure among domestic stallions. Several authors have suggested that such dysfunction may be psychogenic, related to negative experience associated with intense handling and training. An experimental model of experience-related dysfunction was developed by exposing pony stallions to erection-contingent aversive conditioning. This resulted in rapid, specific suppression of sexual arousal and response similar to spontaneously occurring dysfunction. Subsequently, treatm...
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.
Beroza GA, Gentile DG, Goodness P, Charles R.A Robert Jones bandage modified to include a steel walking bar frame and, in one case, side-supporting bars, was applied as a splinting device in 4 horses with hindlimb fractures (3 tarsal and 1 middle phalangeal). The modification was used as an adjunct to previous casting therapies or as a means for handling casting failures or soft tissue problems encountered during the casting period. This means of stabilization is easily adapted to replace a problematic cast in various clinical settings, is easily applied in the standing patient, is easily changed and adjusted on a regular basis, has mini...
Hunt JM, Gerring EL.Prostaglandin E1 was infused intravenously (25, 50 and 75 ng/kg/min) in three ponies. Changes in gastrointestinal mechanical and electrical activity were recorded from chronically implanted strain-gauge force transducers and electrodes. Dose-dependent responses were obtained: there were significant decreases in electrical spiking activity in the stomach, left large colon and small colon, with a corresponding decrease of activity in the left dorsal colon mechanogram. The small intestine was also affected, showing a decrease in both contraction rate and amplitude, which was more marked in the pr...
Godovac-Zimmermann J, Conti A, Liberatori J, Braunitzer G.beta-Lactoglobulin isolated from horse colostrum is heterogeneous and contains two components: beta-lactoglobulin I and beta-lactoglobulin II. These two proteins are monomeric and show differences in their electrophoretic mobilities, chain lengths and primary structures. The complete amino-acid sequence of beta-lactoglobulin II was determined by automated Edman degradation of the intact protein and of the peptides derived from these by digestion with trypsin or chymotrypsin and by chemical cleavage with cyanogen bromide. Unlike other beta-lactoglobulins which contain 162 amino acids, horse bet...
Van Huffel XM, Varner DD, Hinrichs K, Garcia MC, Strzemienski PJ, Kenney RM.A photomicrographic method for evaluation of stallion spermatozoal motility was developed, and spermatozoal image and velocity characteristics were defined. The photomicrographic method was compared with visual estimation of motility in the same semen sample over time. Using photomicrography, velocities and percentages of individual spermatozoal image characteristics were determined. Although there was a high correlation between results of the 2 methods, results of the photomicrographic method were more repeatable than were those of the visual method.
Halnan CR.From the standpoint that cytogenetic screening in mares is seldom necessary as an aid to diagnosis of the gonadal dysgenesis syndrome, a series of double-blind trials were conducted to test the proposal that present practice failed to explore the potential for cytogenetics in clinical practice. It was demonstrated that diagnoses of infertility might be made where mares were found to be of normal phenotype by clinical examination. Such mares were found to be gonosmic mosaics. One stallion had a polymorphism of the X chromosome and had poor conception rates. It was demonstrated that the true val...
French DD, Haynes PF, Miller RI.A horse had severe granulomatous lesions of the upper airways that were attributable to Conidiobolus coronatus. Therapeutic success was documented by clinical examination of the horse 4 years after treatment by surgical extirpation and intralesional and topical use of amphotericin B.
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...
Chan CW, Collins EA.An angiosarcoma involving the right frontal and maxillary sinuses in a nine-year-old Thoroughbred mare was studied post mortem by light and electron microscopy. Important diagnostic features included malignant endothelial cells lining ill-defined vascular spaces, supported by other vasoformative elements. Rhabdomyoblasts were also found. The tumour is apparently rarely seen in the nasal passages of the horse.
Halnan CR.The prognostic use of karyotyping in equine breeding has been recommended since 1976. Specimens used and laboratory methods are described. The system of karyotype evaluation is explained together with a glossary of terms. The principal aberrations in horses are defined. The present state of knowledge in cytogenetics in horses is reviewed dealing with infertility in the mare, where sex chromosomes give clear indication of problems; the situation with respect to anomalies found in stallions and hermaphroditism is explained coupled with recent concepts of chromosomal roles in reproduction. The fu...
Lloyd KC, Harrison I, Tulleners E.A single injection of reserpine in an adult horse was believed to induce toxicosis for several days. Clinical signs included erratic, colic-like behavior followed by depression, bradycardia, miosis, ptosis, and paraphimosis. Diarrhea was not observed and may have been due to the effect of xylazine given with the reserpine. The horse was supported with IV fluids and intensive nursing care. Gradual improvement was noted 72 hours after the horse received the drug. Qualitative analysis via high-performance liquid chromatography was positive for reserpine. Methamphetamine is the recommended antidot...
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.
Hunyadi L, Chigerwe M, Sundman E.SAA is a commonly used biomarker for measuring acute inflammation in equine practice, and the administration of prophylactic plasma to foals is a routine practice in large breeding farms. Despite this, limited information is available on the values of SAA in healthy or sick neonatal foals following this common procedure. A prospective study was conducted with 31 foals from a veterinary hospital in Texas in one year. Enrolled foals were part of a foaling program, where a prophylactic hyperimmunized plasma was administered 12 h after birth. Blood was collected for SAA measurements at birth and ...
Watanabe K, Sohara T, Takeda M, Ueno K, Suzumura N, Rokurouda Y, Rokurouda I, Yamamoto S.Each of five genetic variants of horse serum transferrin (Tf), D, F, H, O, and R, was separated into two bands by polyacrylamide gel isoelectric focusing (PAGIEF). The more acidic band, termed component a, was more abundant than the other one, termed component b, in all variants. Components a and b of TFO variant were immunologically indistinguishable from each other by double immunodiffusion test. Determination of the content ratio of component a to component b in each variant revealed that the variants were classified into two groups: one group (D, F, and H) had a relatively high ratio withi...
Helms CM, Allen PZ.Immunodiffusion analysis of papain digestion products, heavy and light chains of horse IgG-globulins with several rabbit and anti-horse IgG sera, have permitted the demonstration of five antigenic specificities (Fc1, Fc2, L, Lsp and Fabsp) associated with these equine antigens. Reactivity with anti-Fc1 is shown by both F′c and Fc fragments, while anti-Fc2 reactivity is shown only by Fc fragment.
Absorption of anti-Fab serum with L chain Fc fragment provides a reagent (anti-Fabsp) which precipitates only with Fab fragment, IgG-globulin or reduced and alkylated IgG. Upon exposure to deterge...
ALEXANDER F, BENZIE D.1. The disposition and surface relations of the alimentary tract of the foal have been studied radiographically.
2. The rate of progress of a barium meal through the digestive tract was determined. The barium traversed the stomach and ileum of the weaned foal faster than that of the suckling foal, but was longer retained in the cæcum and ventral colon of the weaned foal.
Patterson Rosa L, Troop TW, Martin K, Vierra M, Foster G, Lundquist E, Brooks SA, Lafayette C.Hereditary Equine Regional Dermal Asthenia (HERDA) is an autosomal recessive condition present in the American Quarter Horse and other related breeds. Resulting from a mutation in the peptidyl-prolyl cis-trans isomerase B (PPIB) gene, HERDA is homologous to Ehlers-Danlos syndrome in humans. Characterized by fragile, hyperelastic, skin, HERDA affected horses often present first with slow-healing wounds usually on the dorsum, and resulting in atrophic scars, seromas, and ulcers. As there is no treatment for the condition affected horses are typically reported to be unrideable, and if persisten...
Woolford L, Staniek G, Blunden AS.Pleuropulmonary blastoma (PPB) is a rare biphasic tumor of children formed by mixed epithelial-and-mesenchymal elements. In this article, the authors report a pulmonary mass in an equine fetus with characteristics of PPB. A soft multicystic broad-based pleural mass was identified in the right caudal lung lobe. The mass comprised solid areas of loose mesenchyme, fenestrated by small ducts or large cystic areas lined by cuboidal epithelium. Mesenchymal elements had moderate anisocytosis, anisokaryosis, and cellular pleomorphism and were immunoreactive for vimentin. Epithelial cells lining ducts ...