Equine health encompasses the study and management of diseases, disorders, and overall well-being of horses. It involves understanding various physiological systems, preventive care, and treatment strategies to maintain optimal health in equine populations. Common areas of focus include nutrition, infectious diseases, orthopedic conditions, and reproductive health. Research in equine health aims to advance knowledge on diagnostic methods, therapeutic interventions, and management practices that improve horse welfare and performance. This page collects peer-reviewed research studies and scholarly articles that explore the diverse aspects of equine health, offering insights into current findings and advancements in the field.
Coggins L, Auchnie JA.Equine infectious anemia (EIA) has been enzootic in Hong Kong since the end of World War II. In 1972, a serologic survey of the horses at the Hong Kong Jockey Club indicated 23% prevalence of EIA. Disease control measures were instituted, and the spread of infection was reduced. In 1976, the prevalence of EIA was believed to be sufficiently low to implement procedures for eradication of EIA from all horses in Hong Kong. A correlation between EIA and poor performance of racehorses was demonstrated.
Knill LM, Eagleton RD, Harver E.The equine eye was treated as a general lens system and calculations were done to determine image position in relation to the retina for objects at a distance of infinity, 100 m, and 1 m. The retina is 19.1 mm behind the posterior surface of the lens; therefore, the image appears 14.6 mm posterior to the retina at infinity and at 100 m, and 16.3 mm at 1-m distance on a horizontal axis. The animals studied were hyperopic. It is evident that the horse must move its head or eye, or both, for optimal visual acuity. At the same time, some objects in the total field of vision are imperceptible or in...
Hughes JP, Stabenfeldt GH.A brief review is presented of the use in equine veterinary medicine of anterior pituitary hormones, posterior pituitary hormones, placental hormones, steroid hormones and prostaglandins. These hormones are used frequently in clinical application without a scientific basis for their expected activity.
Martin CJ, Chihara S, Chang DB.Alveolar wall from the lung of aging humans shows a progressive decrease in maximal extensibility, which should follow an increase in resting tissue length rather than a reduction in maximal length. An increase in resting tissue length is compatible with the change in lung volumes and reduction in elastic recoil that occurs with time. A model of the lung was used to compare the effects of a change in resting tissue length in diminishing elastic recoil with that of a reduction in the volume density of the elastic elements (emphysema). Such differentiation is important in selecting an animal tha...
McGuire TC, Crawford TB, Hallowell AL, Macomber LE.Failure in colostral immunoglobulin G (IgG) transfer was found in 9 of 87 Thoroughbred foals. Seven (78%) of these 9 foals acquired infections requiring therapy. Twelve of the foals had partial failure in colostral IgG transfer, and 3 of these had infections requiring therapy. The remaining 66 foals had normal transfer of colostral IgG, and only 2 had detectable infections. The failure of colostral IgG transfer was attributable to nursing problems in only one case. When presuckle postpartum colostrum was collected, 2 of 4 failures of colostral IgG transfer and 4 of 6 partial failures of colost...
Garner HE, Hahn AW, Salem C, Coffman JR, Hutcheson DP, Johnson JH.Acute laminitis-hypertension was produced experimentally by carbohydrate overloading of the gastrointestinal tract in 8 horses, and the resulting hemodynamic changes were measured. Statistically significant (P less than 0.01) increases in cardiac output, left ventricular ejection rate, heart rate, and arterial pressure were related to statistically nonsignificant changes in peripheral resistance and a delayed (Obel grade 3 plus 24 hours) decrease in plasma volume. When compared with control values, the doubling of cardiac output and left ventricular ejection rate simultaneous with little or no...
Frost GE, du Preez HR.A 3 year old thoroughbred colt in full training pulled up
acutely lame during a training gallop on a dirt track.
According to the trainer no reason for the injury was
evident. The horse refused to bear weight on the leg
and when forced to walk back to the stables it would
only touch the affected toe to the ground. The fetlock
soon became swollen and was very painful. The trainer
treated the animal for a sprain with ice packs and
bandages. No improvement occurred in 72 hours and
veterinary advice was sought.
Examination revealed the horse to be in obvious
pain. He was unable to bear ...
Hughes JP, Trommershausen-Smith A.Reproductive failure was studied in 12 phenotypically normal mares (9 Arabian, 3 Quarter horses, 1 Appaloosa and 1 pony). Karyotyping was performed using lymphocytes isolated from peripheral blood by density gradient procedures, followed by standard culture methods for karyotyping. Nine mares had karyotypes of 63,XO; 1 had 63,XO/64,XX; 1 had 63,XO/64,XY and 1 had 64,XY. All mares had small, firm ovaries that when removed and examined from 4 mares, lacked germ cells and consisted of undifferentiated ovarian stroma.
McMullan WC, Joyce JR, Hanselka DV, Heitmann JM.Amphotericin B was used systemically or locally, or both, in the treatment of localized subcutaneous phycomycosis in horses. In 8 of 10 cases, the results were satisfactory. Intravenous treatment was well tolerated at an average starting daily dosage of 0.38 mg/kg, increasing up to as high as 1.47 mg/kg. It was concluded that the ideal treatment regimen would include early surgical removal of the lesion followed by daily intravenous and topical administration of amphotericin B, with periodic extirpation of small necrotic tracts as necessary.
Burrows R, Spooner PR, Goodridge D.Ponies held in isolation for 40 months were vaccinated and revaccinated with four commercial equine influenza vaccines. Little or no HI antibody was detected after the first inoculation; second and subsequent annual revaccinations produced peak HI antibody titres between 7 and 14 days. Titres fell quickly between 14 and 28 days and less quickly thereafter. The decline of HI antibody appeared to be related more to the initial titre attained and to the period after vaccination than to the composition of the vaccine. The response to a first annual revaccination was superior to that produced by a ...
Hilbert BJ, Farrell RK, Grant BD.Squamous cell carcinoma around the eyes of 3 horses was treated with liquid nitrogen, using cryotherapy probes as the method of application. In 2 cases, there was complete regression of the tumor; in the 3rd case, remission and relief of discomfort were temporary.
Lyons ET, Drudge JH, Tolliver SC.In 1 experiment, a prepatent period of 8 or 9 days was recorded for Strongyloides westeri in 4 pony foals raised worm-free but infected with parasitic 3rd stage larvae in the postpartum milk of a mare via gastric intubation. This is about 2 to 6 days less than the usual age that eggs of S westeri appear in the feces of naturally infected suckling foals, in central Kentucky.
In other studies, mares were treated with cambendazole or thiabendazole at 0 to 2 days after parturition and continued for 7 to 16 days. Appearance of S westeri eggs in feces of foals nursing treated mares was prevented ...
Jackson TA, Osburn BI, Cordy DR, Kendrick JW.Experimental infection with equine herpesvirus 1 (rhinopneumonitis) resulted in neurologic disease in 8 of 15 inoculated horses. Nonpregnant animals did not develop clinical disease, and microscopic examination of tissues revealed no changes. In all mares between 3 and 9 months of gestation, a neurologic syndrome appeared 6 to 8 days after inoculation. Mares inoculated when 10 months pregnant did not develop neurologic disorders, but several aborted. The histopathologic change common to both sequelae was vasculitis, involving smaller arteries and veins. Although blood vessel changes were detec...
Dubey JP, Streitel RH, Stromberg PC, Toussant MJ.Hearts, diaphragms, esophagi, and spinal cords from 266 horses were obtained at slaughter in Creston, Ohio. Tissues were examined microscopically for Sarcocystis in sections, digested in trypsin to obtain bradyzoites, and fed to 10 dogs and 10 cats. Intramuscular cysts were found in selections of two hearts from 57 horses and four esophagi from 107 horses. The cysts were up to 900 micron long and up to 70 micron wide. The cyst wall was 1 to 2 micron thick and cross-striated. The enclosed bradyzoites were banana-shaped, 15 to 20 by 20 to 3 micron, and contained several PAS-positive granules. Br...
Lyons ET, Drudge JH, Tolliver SC.Thirteen critical tests were conducted in horses naturally infected with helminths and bots. Single doses of thiabendazole (44 mg/kg of body weight) and trichlorfon (40 mg/kg of body weight) powder formulations were administered as suspensions sequentially given via stomach tube to evaluate the efficacy of the combination against the large parasites of horses. Parasite removal efficacies were 100% against 2nd instar Gasterophilus intestinalis and 2nd and 3rd instar Gasterophilus nasalis and 82 to 100% against 3rd instar G intestinals. There were complete removals of mature and immature Parasca...
Lee CG, Ross AD.Klossiella equi in the kidney of a horse is described. Gametocytic and sporogonic stages were observed in the epithelium of the collecting tubules in association with schizonts in the glomeruli and proximal convoluted tubules. The condition was asymptomatic and caused only minor renal damage and inflammation.
Powell DG, Burrows R, Spooner P, Mumford J, Thomson G.The observations reported in this paper were obtained as part of a long term surveillance programme designed to monitor the efficacy of influenza vaccines and study the prevalence of influenza and other respiratory viruses among horses in Britain. Inactivated influenza vaccines were found to be effective in protecting horses from disease caused by influenza A/equine-1 but were less successful in protecting horses against influenza A/equine-2. The paper presents the clinical, epidemiological virological and serological findings obtained between 1971 and 1976.
Stewart F, Allen WR, Moor RM.Rat testicular radioreceptor assays specific for FSH and LH were used to determine the FSH:LH ratio of PMSG produced by horse, donkey, mule and hinny conceptuses. Measurements of FSH and LH activities in PMSG produced both in vivo and in vitro by the four types of conceptuses showed that the genotype of the foetus markedly influences the FSH:LH ratio of PMSG. The FSH:LH ratio of PMSG produced by the horse conceptus was around unity whereas the ratio of PMSG produced by the donkey conceptus was as low as 0-2. Furthermore, the hybrid mule and hinny conceptuses both produced PMSG with an FSH:LH r...
Teruya JM, Santa Rosa CA, Giorgi W, Yanaguita RM.A serological examination was carried out for L. monocytogenes antibodies on 9,318 domestic animal--7,809 bovine, 838 horses and 671 swine--in São Paulo, Brazil. Serum agglutination in tubes was the method used. Only somatic antigens from serotypes 1, 2, 3, 4a and 4b were employed. It was considered reagent all sera reacting in a titer 1/20 while as positive only sera with 1/320 or above. According this criteria the results showed showed that in cattle 17.8% were reagent but only 8 sera were positive for types 1, 2 and 4b. Only type 1 was found in horses in a rate of 22.7% reagent, and 11 pos...
Nickels FA, Brown CM, Breeze RG.A unilateral pulmonary granular cell tumor occurred in a Thoroughbred mare with longstanding respiratory disease wrongly attributed to chronic obstructive pulmonary disease. The clinical features, radiology and endoscopic appearance permitted an accurate diagnosis, which was supported by subsequent necropsy and histologic examination. Obstructive pulmonary disease was ruled out after measurement of arterial blood gases and maximum intrathoracic pressure changes, and after microscopic examination of the lung.
Köhne M, Kirch F, Tönissen A, Martinsson G, Rabe U, Sieme H, Schuberth HJ.To improve accuracy in evaluating stallion ejaculates, an antibody-based, flow cytometric assay for the detection and identification of leukocyte subpopulations (CD4-, CD8-, CD21-, CD172a-positive cells) in stallion semen (n = 12) was established. For establishment of the assay, native semen was supplemented with blood leukocytes (control: 20% leukocytes, 80% sperm cells) and analysed by flow cytometry. Adding antioxidants (ascorbic acid and butylated hydroxytoluol) to semen immediately after collection inhibited rapid death of lymphoid cells in sperm leukocyte mixtures. In control set-ups...
Chapman DI, Moss MS, Tomlinson PW, Harrison MP, Simmons PJ.1. Following single intramuscular doses of [14C]fluprostenol (0.5--2.4 micrograms/kg) to three female horses and to three gelded male horses, radioactivity was present in the plasma within 5 min; peak concn. (0.32--1.30 ng/ml fluprostenol equiv.) occurred 5 to 90 min after injection. Radioactivity was still present in the plasma of the females after three days. About 88% of fluprostenol is bound to plasma proteins. 2. Radioactivity was present in the parotid saliva of the gelded male horses within 10 min. Peak concn. (45--91 pg/ml fluprostenol equiv.) occurred from 5 min to 1 h after injection...
Gentry PA, Feldman BF, O'Neill SL.The purpose of this study was to evaluate the effect of modifying commercial reagents for the laboratory evaluation of several haemostatic parameters in normal, non-pregnant mares. The routine coagulation screening assays, namely, the activated partial thromboplastin time (APTT) and the one-stage prothrombin time (PT), and the specific coagulation assays for the determination of the biological activity of Factors VII, VIII:C and IX, are discussed.
Leeb T.The growing knowledge on physiology, cell biology and biochemistry of the reproductive organs has provided many insights into molecular mechanisms that are required for successful reproduction. Research directed at the investigation of reproduction physiology in domestic animals was hampered in the past by a lack of species-specific genomic information. The genome sequences of dog, cattle and horse have become publicly available in 2005, 2006 and 2007 respectively. Although the gene content of mammalian genomes is generally very similar, genes involved in reproduction tend to be less conserved...
Dusek J, Munk Z.The breeding documentation of the English Thoroughbred horse breeding farm at Napajedla was analyzed to study some effects acting upon the fertility of studs and mares and the length of gravidity. The heritability of fertility is the subject of this report. The normality of the distribution of fertility was tested by processing 300 data on fertility at the given significance level sup / Fn(xi) - F(xi) / less than or equal to Dn(a). The value of the supreme D(300) = 0.108 is lower than the critical level for alpha 0.05. The estimation of fertility heritability coefficient indicates that h2 = 0....
Kalemkerian PB, Metz GE, Peral-Garcia P, Echeverria MG, Giovambattista G, Díaz S.Polymorphisms at Major Histocompatibility Complex (MHC) genes have been associated with resistance/susceptibility to infectious diseases in domestic animals. The aim of this investigation was to evaluate whether polymorphisms of the DRA gene the Equine Lymphocyte Antigen is associated with susceptibility to Equine Arteritis Virus (EAV) infection in horses in Argentina. The equine DRA gene was screened for polymorphisms using Pyrosequencing® Technology which allowed the detection of three ELA-DRA exon 2 alleles. Neither allele frequencies nor genotypic differentiation exhibited any statistical...
Baccarin RY, Martins EA, Hagen SC, Silva LC.A controlled study was designed in order to evaluate the effects of medial patellar desmotomy (MPD), combined with exercise restriction, on clinically and radiographically normal femoropatellar joints, and to identify the patellar instability by radiographic examination. MPD was performed on the right hind limb and the horses were rested for 120 days. Both hind limbs were radiographed before surgery and at 15, 30, 60, 90, and 120 days after MPD, obtaining lateromedial, flexed lateromedial, caudocranial and cranioproximal-craniodistal (skyline) views. The femorotibial and femoropatellar angles ...
Montavon S.The aim of this review is to give the practitioner the ability to be familiar with the echographic exam of ovarian abnormalities. He should be able to recognize different stages of the development of these important structures and to estimate the effect that they can have on the normal cycle of the mare. Various specific criteria and details regarding the equine echography of ovarian abnormalities are reported and illustrated, using the last scientific data published on that particular topic.
Ryan D.Outbreaks of equine influenza (EI) cause major disruption to the racing industry, resulting in cessation of racing until affected horses have recovered from the disease. The introduction of EI to a large population of Thoroughbred horses stabled at a Sydney racecourse provided the opportunity to observe clinical signs and monitor the spread of EI in this predominantly naïve population and to assist in determining an endpoint to infection spread to allow resumption of racing events.
Charleston W, McKenna P.Abstract A general review of the epidemiology, significance and control of nematode parasitism of sheep, goats, cattle and deer in New Zealand, the emergence of anthelmintic resistance and its effects, and the search for parasite control strategies that reduce reliance on anthelmintic use, is provided. The research that has formed the basis for present levels of understanding of this complex and important topic is summarised and sources of further information are indicated. Aspects of nematode infections of horses, pigs, dogs and cats, and the history of the liver fluke, Fasciola hepatica, in ...
Martinuk SD, Bristol F, Murphy BD.Breeding trials were designed to determine the influence of the mare on serum concentrations of equine chorionic gonadotropin (eCG) from Day 39 to Day 104 of gestation. Sires were ranked according to mean eCG concentrations found in the groups of randomly selected mares to which they were mated in 1983. Mares were ranked according to their mean eCG concentrations on Days 55, 71 and 85 of gestation (Day 0 = mating), in 1983 and 1985. In the 1986 breeding season, mares that had pregnancies characterized by high eCG levels were mated to sires previously associated with low eCG concentration pregn...
MacDonald MH.Examination of the equine head should be a routine part of any complete physical examination. It can be performed rapidly and efficiently while providing important information about the health and function of several major body systems.
Wenzel R, Major D, Hesp K, Doble P.Regulating authorities in the racing industry have restricted the administration of potentially performance enhancing cobalt salts to horses. There are severe penalties for trainers presenting horses with elevated urine cobalt concentrations, and compliance is ensured via analysis of total urinary cobalt at thresholds of 100 μg/L. When cobalt is present as part of the cobalamin molecule it is not considered performance enhancing. This paper demonstrates that a horse can excrete a significant proportion of a commercially available vitamin B12 injection in urine without metabolic modification...
Dodman NH.Drugs and drug combinations currently in use for chemical restraint of the horse are discussed with a view to establishing their likely usefulness to the practising veterinary surgeon. Acepromazine maleate and xylazine hydrochloride are considered to be the most useful tranquillisers in spite of their limitations. A xylazine-methadone sequence is described for more profound chemical restraint and the possible future role of ketamine and glyceryl guaiacolate in combination with other agents to produce recumbency is discussed.