Disease etiology in horses refers to the study of the causes and development of diseases within equine populations. It encompasses various factors, including genetic predisposition, environmental influences, infectious agents, and nutritional imbalances, that contribute to the onset and progression of diseases in horses. Understanding disease etiology is essential for identifying risk factors and implementing preventative measures in equine health management. This topic includes research on pathogen-host interactions, the impact of management practices on disease incidence, and the role of genetic and environmental factors in disease susceptibility. This page compiles peer-reviewed research studies and scholarly articles that explore the mechanisms, contributing factors, and implications of disease etiology in horses.
Updike SJ.Tendons of insertion of the equine tibialis cranialis muscle and peroneus tertius muscle (PT) were dissected grossly. Precise areas of tendon attachment and fiber arrangements within the tendons were described for the dorsal and medial tendons of the tibialis cranialis, and for the superficial lateral, deep lateral, dorsal, and medial tendons of the PT. Direct attachment of the dorsal and medial tendons of the PT into the periosteum of the central and 3rd tarsal bones and the 3rd metatarsal bone indicates that the PT may be involved in the pathogenesis of hock lamenesses.
Irvine CH.Hypothyroidism in the foal occurs as two entities because of the separate actions of thyroid hormones in regulation of metabolic rate and in cell differentiation. The hypometabolic state which results in inadequate thermogenesis and lethargy, occurs concurrently with a period when thyroid hormone secretion is inadequate. Also the severity of the concurrent symptoms is related to the degree of hormone inadequacy as measured by plasma concentrations of free T4 and T3. By contrast, the developmental lesions caused by hypothyroidism are often observed during periods when plasma thyroid hormone con...
Kosch PC, Koterba AM, Coons TJ, Webb AI.Developments in evaluation of newborn foals with respiratory distress are discussed. Major causes of respiratory distress are outlined and discussed in terms of the similar respiratory signs exhibited by foals with this clinical syndrome. History, physical examination, clinical pathology, chest radiography and blood gas analyses are discussed as important elements of the evaluation of the condition of these foals. Foals with respiratory disease are grouped into three major categories on the basis of clinical signs and arterial blood gas profiles. The evaluation of foals with respiratory distre...
Mugg PA, Hill A.The failure of N. gonorrhoeae to grow on isolation media was found to be due to inhibitory substances present in commercially available horse sera. Subsequent investigations indicated that the inhibitory action of the horse serum may have been due to antibodies to N. gonorrhoeae, H. influenzae, H. parainfluenzae and beta hemolytic streptococci. This experience highlights the need for media quality control programmes in laboratories which prepare microbiological culture media.
Prescott JF, Gannon VP, Kittler G, Hlywka G.Results are presented of antimicrobial disc diffusion susceptibility testing on commonly isolated bacterial pathogens made at the Ontario Veterinary College Diagnostic Bacteriology Laboratory in 1981 and 1982. Nearly 2 000 isolates from horses, cattle, dogs and cats were tested. Comparison of resistance in the same bacterial species isolated from different animal species showed significant differences between some of the same antibiotics.
Smith KM, Barber SM.A two year old Thoroughbred gelding, presented with guttural pouch hemorrhage, had the internal and external carotid arteries ligated. Guttural pouch mycosis was detected on endoscopic examination. After one month of topical antifungal therapy, the horse was returned and euthanized because of recurrent epistaxis. A bacterial infection of the guttural pouch with associated ulceration and hemorrhage from the maxillary artery was found at necropsy.A two year old grade gelding had ulceration and hemorrhage from the external carotid artery. Utilizing balloon-tipped catheters and arterial ligation, ...
Rebhun WC, Tennant BC, Dill SG, King JM.Renal toxicosis attributable to vitamin K3 (menadione sodium bisulfite) was suspected in 5 young adult horses in which acute renal failure developed following parenteral administration of vitamin K3 at the manufacturers' recommended dosages. Renal disease was subsequently induced experimentally in 5 of 6 horses by administration of vitamin K3 at manufacturers' recommended dosages. Signs of renal disease in the clinical patients as well as in the horses treated experimentally included renal colic, hematuria, azotemia, and electrolyte abnormalities consistent with acute renal failure. Two clinic...
Breeze RG, Legreid WW, Bayly WM, Wilson BJ.Perilla ketone was assessed for its usefulness as a model of equine restrictive pulmonary disease. Three ponies were given 18 mg/kg bodyweight synthetic perilla ketone in dimethyl-sulphoxide. Within 24 h of administration, respiratory rate, peak inspiratory and expiratory flow rates and minute volume were increased. By 48 h there was a significant decrease in tidal volume, and blood pH and base excess were also decreased but not outside normal limits. At necropsy there was congestion and oedema of the lungs. Histologically there was diffuse alveolar injury but no evidence of significant obstru...
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.
Higgins AJ, Lees P, Wright JA.In a series of experiments to examine equine inflammatory exudates for the presence of metabolites of arachidonic acid, including prostaglandin E2 (PGE2), a model for the induction and collection of exudates in ponies has been developed. Multiperforated polypropylene practice golf balls implanted subcutaneously in the mid-neck region were well tolerated and proved to be the most successful model. One such cage was implanted in the neck of each of seven ponies. Inflammatory exudates were induced by injecting 3.0 or 0.5 ml carrageenin into the cages and aspirates collected between three and 48 h...
Rugh KS, Garner HE, Hatfield DG, Herrold D.Six adult ponies were trained calmly to assume and maintain left lateral recumbency without the use of sedative or immobilising agents. During a 30 min recumbent period, pHa, arterial oxygen and carbon dioxide tensions (PaO2 and PaCO2) and heart and respiratory rates were monitored at regular intervals to evaluate ventilatory response. Overall, there were no statistically significant differences found between mean control and recumbent or final standing values. When lightweight ponies were compared to heavyweight ponies, only mean PaO2 at 10 mins recumbency was different. This information supp...
Miller RI, Campbell RS.Pythiosis (204 cases, 77%), basidiobolomycosis (48 cases, 18%), and conidiobolomycosis (14 cases, 5%) were diagnosed morphologically from 266 horses with phycomycosis. All lesions were cutaneous ulcerative granulomas and three horses with pythiosis had metastatic lesions in regional lymph nodes. Lesions of pythiosis contained characteristic yellow, coral-like coagula and had a fibrotic surface containing sinus tract openings. Basidiobolomycosis was characterized by infrequent small yellow coagula and a yellow line of fungal invasion beneath an edematous surface. Lesions of conidiobolomycosis h...
Lyons ET, Drudge JH, Tolliver SC, Swerczek TW, Crowe MW.A total of 396 Thoroughbreds (86 males, 293 females, and 17 geldings) in Kentucky, 1 to 30 years of age, were examined at necropsy for presence of Anoplocephala perfoliata (2 female horses were not examined) in the cecum for lesions of Draschia megastoma in the stomach, during the 1-year period of Mar 1, 1982 through Feb 28, 1983. Prevalence of A perfoliata was 53% and of lesions of D megastoma was 63%. All lesions of D megastoma were partially or entirely in the glandular region of the stomach. Distances of the midpoint of these lesions from the margo plicatus varied from 0 to 290 mm. The cen...
Lindberg R.A morphological study on equine granulomatous enteritis (EGE) in 13 horses is presented. All horses were young (1 to 5 years old) standardbreds. Based on gross pathology, cases were classified into those with diffuse (11 cases) and those with localized (2 cases) small bowel lesions. The granulomatous reaction in the gut was marked by diffuse and patchy infiltrates and distinct granulomas, composed of epithelioid cells, macrophages and lymphoid cells, and was devoid of necrosis. Salient accompanying features of the small bowel included lymphoid hyperplasia, peri-lymphatic and transmural inflamm...
Aguilar CM, Fernández E, de Fernández R, Deane LM.During an outbreak of cutaneous leishmaniasis in a locality (Las Rosas, Cojedes State, Venezuela) previously non-endemic, 12.9% of humans, 7% of dogs and 21.4% of donkeys (Equus asinus) had lesions with parasites. The agent in the three hosts was identified as Leishmania braziliensis, subspecies braziliensis at least in man and donkey. The probable vector was Lutzomyia panamensis. No infection was found in a small sample of wild mammals examined. The outbreak was apparently linked with the importation of donkeys with ulcers, from endemic areas. The authors call attention to the fact that not o...
Noschka E, Moore JN, Peroni JF, Lewis SJ, Morrow JD, Robertson TP.Inflammation and vascular dysfunction occur concurrently during the prodromal stages of equine laminitis. The aim of this study was to provide insights into the role that thromboxane and isoprostanes may play in the development of black walnut heartwood extract (BWHE)-induced laminitis. Horses were divided into two groups, either control or BWHE-administered horses. Plasma concentrations of thromboxane increased transiently after administration of BWHE and coincided with the nadir in white blood cell counts, whereas plasma concentrations of iso-prostaglandin PGF(2alpha) (iso-PGF(2alpha)) did n...
Heinrich B.This research article corrects a common misconception about the energy metabolism in horses during short sprinting and long-distance running events, emphasizing that short sprints are primarily powered by anaerobic activity, […]
Rothwell TL, Merritt GC, Middleton DJ, Rose RJ.The research article describes the possibility of a horse affected by pemphigus foliaceus, a type of uncommon skin disease that is normally observed in humans, characterized by shallow erosions, scales, […]
Anderson BH, Firth EC, Whittem T.Plasma (P), synovial fluid (SF) and lymph (L) concentrations of gentamicin were studied in two trials. A lymph vessel in the hindlimb was cannulated. The day after surgery (trial A), P and L samples were collected for 12 h after intravenous injection of gentamicin sulphate at 2.2 mg/kg dose rate. Approximately 48 h after surgery (trial B), the fetlock joint of the cannulated hindlimb was catheterized and P, SF and L samples collected for 12 h after a similar intravenous injection. The kinetic parameters were similar to those in other reports and did not differ between trials (P < 0.05). The P,...
ROBERTS SR.The research article explores the origin or causation (etiology) of an ancient horse disease known as equine periodic ophthalmia, where clinical and pathological investigations have yet to yield conclusive results. […]
Mayr A, Thein P.At the moment, horse praxis is confronted by two disease complexes which are difficult to fight against as well in prophylaxis as in therapy, but which get an increasing importance. First they concern virus infections of the foals and second primary virus-caused respiratory diseases. Foals get infected during the embryonal/fetal development, in the perinatal or postnatal period. Normally the infection is caused by latent infected, clinical healthy mares, or in the postnatal period by ubiquitous, normally opportunistic socalled problem-viruses, i.e. equine herpes-viruses 1 and 2, rota-, corona-...