Equine Science encompasses the study of horses and their management, health, and performance. This field integrates various scientific disciplines such as biology, genetics, nutrition, physiology, and veterinary medicine to understand and improve the well-being and capabilities of horses. Areas of focus include equine anatomy, reproduction, behavior, and disease prevention. Research in equine science aims to enhance horse care, optimize training and performance, and address health challenges. This page compiles peer-reviewed research studies and scholarly articles that explore the diverse aspects of equine science, providing insights into the latest advancements and methodologies in the field.
Pope DC, Heslop CH.An outbreak of myoglobinuria under unusual circumstances in a group of four horses, together with the events leading up to the diagnosis, is described, and a brief mention of two previously recorded similar cases is made.
BRAYE ET, HINSMAN EJ, RILEY WF.No horse receiving combined streptokinase, streptodornase, and human plasminogen alone in either 125,000-unit or 375,000-unit doses manifested any clinical reaction. Untoward reactions occurred in 2 horses receiving both the combined streptokinase, streptodornase, and human plasminogen (125,000 units), and chlortetracycline. The reaction was transitory and subsided without treatment.
Monreal L, Villatoro AJ, Hooghuis H, Ros I, Timoney PJ.During 1992, a widespread outbreak of Equine viral arteritis (EVA) occurred at a riding establishment near Barcelona, Spain. A total of 31 out of 186 horses on the premises displayed clinical signs, most frequently, fever, depression, mild ventral and limb oedema and a vesicular-erosive stomatitis, with hypersalivation, petechiations and small ulcerations. Affected horses developed illness of varying severity with only a few exhibiting a severe form of the disease and no mortality was recorded. Haematological and blood biochemical examination the most severely affected horses revealed a thromb...
Lowry TF, Forster HV, Forster MA, Murphy CL, Brice AG, Pan LG.The objective of the present study was to determine the effect of elevated inspired CO2 on respiratory dead space (VD) of 12 normal, 8 carotid body-denervated (CBD), 7 hilar nerve-denervated (HND), and 6 CBD+HND ponies. The Fowler technique was used to determine VD on a breath-by-breath basis while the ponies breathed room air and inspired CO2 at 3 and 6%. During room air breathing, tidal volume (VT) and VD were greater in HND ponies than in normal and CBD ponies (P less than 0.05), and VT was less and VD/VT was greater after CBD than before CBD. For all groups. VD, VT, and breathing frequency...
Lees MJ, Fretz PB, Bowen CV, Leach DH.Equine limb wounds often heal slowly by epithelialization, and large scars are a frequent end result. In some ways, they resemble the wound associated with human tibial injuries. The literature indicates that previous investigators have failed to transfer free skin flaps successfully in the horse. In this paper, we review our experimental work with the deep circumflex iliac flap in the horse. Dissections of 20 cadavers confirmed the anatomical consistency of the flap. Four flaps survived well when elevated as island flaps, but five orthotopic and nine heterotopic free flap transfers all failed...
Tinel JB, Veras MM, Waked D, Alonso MA, Fernandes CB.Mules are derived from crossing horse mares with a donkey, in which the interest is due to gentleness and ability to work and equestrian sports. As the placenta is responsible for fetal development and maturation, knowing its typical microstructure allows us to understand how fetomaternal interactions occur in this interspecific pregnancy. Thus, the study performed a comparative stereological evaluation of volumetric composition and fetomaternal contact surface in the uterine body (UB), gravid uterine horn (GUH), and nongravid uterine horn (NGUH) of Mangalarga Paulista mare's term allantochori...
Rainger JE, Wardius S, Medina-Torres CE, Dempsey SM, Perkins N, van Eps AW.Regional hypothermia has shown promise as analgesic in horses when used to manage painful conditions of the distal limb such as laminitis. In this prospective study, the analgesic effects of regional hypothermia were assessed using mechanical nociceptive thresholds during distal limb cooling. The study population consisted of eight healthy adult Standardbred horses, selected from a teaching herd. A distal forelimb of each horse was cooled using water immersion at the following sequential target water temperatures: 34 °C, 20 °C, 10 °C, 5 °C, 1 °C, 5 °C, 10 °C, 20 °C. Limb surface temper...
Luo Y, Rudy JA, Uboh CE, Soma LR, Guan F, Enright JM, Tsang DS.The method describes quantification and confirmation of flunixin in equine plasma by liquid chromatography-quadrupole time-of-flight mass spectrometry (LC/Q-TOF/MS/MS). Samples were screened by enzyme-linked immunosorbent assay (ELISA) and only those samples presumptively declared positive were subjected to quantification and confirmation for the presence of flunixin by this method. The method is also readily adaptable to instrumental screening for the analyte. Flunixin was recovered from plasma by liquid-liquid extraction (LLE). The sample was diluted with 2 ml saturated phosphate buffer (pH ...
Koneberg DG, Edinger J.The purpose of this in vitro study was to evaluate the value of three-dimensional (3D) ultrasonography for the diagnosis of equine meniscal and trochlear ridge lesions under in vitro conditions. Lesions were created in the isolated meniscus and femoral trochlea of 25 cadaver stifle joints. Cylindric, conic, and cuboid lesions were created on the trochlear ridge. Five different meniscal tear configurations were created. A total of 107 lesions of the trochlear ridge and 103 lesions of the meniscus were created. 3D ultrasonography was performed in a waterbath, using a 7.5 MHz 3D scanner. Trochlea...
Chuang MS, Huang HH, Dixon KM, Chen KS, Mao CL, Chen CL.The pharmacokinetics of clenbuterol in equine urine and blood was investigated. Methods: Urine and blood samples were collected following 3-day multiple oral administrations. The samples were examined using enzyme-linked immunosorbent assay and further confirmed by solid phase extraction and capillary electrophoresis. Results: Urinary clenbuterol was detectable until day 14 after the last dose. The urinary excretion of clenbuterol was characterized by a biphasic pattern. The half-lives of the bi-exponential elimination (t(1/2alpha) and t(1/2beta)) for urinary clenbuterol were about 12.1 and 48...
Kim JY, Choi MH, Kim SJ, Chung BC.A high-performance liquid chromatographic-tandem mass spectrometric (HPLC/MS/MS) method for the determination of 19-nortestosterone and its esters (cyclopentanepropionate, phenylpropionate, and decanoate) in equine plasma is achieved using an atmospheric pressure chemical ionization (APCI) interface in selected reaction monitoring (SRM) mode. The two internal standards used were 16,16, 17-(2)H(3)-19-nortestosterone for 19-nortestosterone and methenolone acetate for its esters. The steroids studied were extracted from plasma samples with a mixture of diethyl ether/n-hexane (9:1, v/v). The quant...
Dippert KD, Hofferer S, Palmer E, Jasko DJ, Squires EL.Cyclic mares were assigned to 1 of 3 treatments (n=15 per group): Group 1 received equine pituitary extract (EPE; 25 mg, i.m.) on Day 5 after ovulation; Group 2 received EPE on Day 12 after ovulation; while Group 3 received 3.3 mg of GnRH analogue (buserelin implant) on the day of ovulation and 25 mg, i.m. EPE on Day 12. Mares in each group were given 10 mg PGF2alpha on the first and second day of EPE treatment. The EPE treatment was continued daily until the first spontaneous ovulation, at which time 3,300 IU of human chorionic gonadotropin (hCG) were given to induce further ovulations. Mares...
Evans-Clay M, Porch N, Maguire G, Weston MA.Beaches are under increasing pressure from a wide range of anthropogenic threats, including human trampling, vehicular crushing, and horse riding/training. The impacts of horses on beaches are unknown. We index the relative abundance, diversity and assemblage composition of beach invertebrates at paired sites with and without horses at nine beaches (locations) across Victoria, Australia. Horses were more common at sites where they were allowed and sites (horse versus no horse) within beaches were well matched, having similar slope, seaweed coverage, human and dog activity-attributes which vari...
Johnson AL.A study was conducted to evaluate the effectiveness of gonadotropin-releasing hormone (GnRH) pulse infusion to stimulate follicular development and induce ovulation in seasonally anestrous standardbred mares. Seventeen mares were selected for use in this experiment, on the basis of a previous normal reproductive history, and were housed under a photoperiod of 8L:16D beginning one week prior to the start of the experiment (second week in January). Mares were infused with 20 micrograms (n = 7) or 2 micrograms (n = 6) GnRH/h, or were subjected to photoperiod treatment only (controls, n = 4). Seru...
Watson TD, Burns L, Freeman DJ, Packard CJ, Shepherd J.1. Apolipoprotein A-I dependent lecithin:cholesterol acyl transferase (LCAT) activity was identified in equine lipoprotein deficient plasma (LPDP). 2. LCAT activity showed no breed or sex variation, and was unaltered postprandially. 3. There was no significant cholesteryl ester transfer activity in equine LPDP. 4. Hydrophobic interaction chromatography on phenyl sepharose failed to unmask transfer activity or identify an inhibitor of cholesteryl ester transfer. 5. In 12 Shetland ponies, plasma high density lipoprotein (HDL) concentrations were positively correlated with those of triglyceride, ...
Nauwelaerts S, Kaiser L, Malinowski R, Clayton HM.The estimation of the position of the center of mass (CM) is essential in a wide range of biomechanical analyses. In horses, the majority of the body mass is contained in the trunk and in most studies, the trunk is assumed to be rigid. However, this rigidity assumption has not been tested. We quantified changes in the position of the trunk CM due to external shape changes by measuring the kinematics of a mesh encompassing the trunk. Using a frame of reference fixed to the horse's spine, we described the shape deformation of the trunk during walking. In addition, we tested for speed and individ...
Yordanov G, Zlatanovic N, Palova N, Mehandjyiski I, Neov B, Radoslavov G, Hristov P.The objective of our study was to investigate the genetic structure of yet uninvestigated populations of three closely related horse breeds - the Danubian Horse, the Hungarian Nonius and the Serbian Nonius - in order to clarify their origin and genetic diversity. A 640-bp-long fragment of the mtDNA D-loop region was amplified and sequenced. The results showed that the investigated breeds have different genetic profiles although they share some common characteristics. We identified nine of the 17 haplogroups described in modern horses. Most of the obtained sequences fall into the M, L, G, and O...
Atayde L, Rocha A.It is important to get mares pregnant as early as possible after vernal transition and thus, identification signs of impending 1st ovulation of the year are warranted. To identify clinical indicators of an approaching first ovulation of the year, mares were teased with a stallion for oestrous detection starting January 3 and subjected to ultrasonographic examination. Day of first appearance of uterus oedema, follicular wall invagination, intrafollicular echogenicity, double contour of the follicle wall, increase in granulosa thickness, follicular wall hyperechogenicity and appearance of pear-s...
Allen WR, Bowen JM, Frank CJ, Jeffcott LB, Rossdale PD.This short review article describes the various techniques currently available for artificial insemination in the horse. The collection and use of raw and extended semen is discussed together with the more recent developments in freezing semen. The expected conception rates with both fresh and frozen semen are quoted. The possible benefits in disease control and stud management are discussed, as well as the difficulties in controlling the use of A.I. from the Breed Registration Authorities point of view.
Brown CM.This article reviews the etiology, clinical findings, and significance of diseases of the heart valves, myocardium, pericardium, and great vessels of the horse. Each valve is considered separately from the point of view of murmur production. In addition, the role of the cardiovascular system in the etiology of sudden and unexpected death is considered.
Forster HV, Pan LG, Flynn C, Bisgard GE, Hoffer RE.We determined whether the [CO2] in the upper airways (UA) can influence breathing in ponies and whether UA [CO2] contributes to the attenuation of a thermal tachypnea during periods of elevated inspired CO2. Six ponies were studied 1 mo after chronic tracheostomies were created. For one protocol the ponies were breathing room air through a cuffed endotracheal tube. Another smaller tube was placed in the tracheostomy and directed up the airway. By use of this tube, a pump, and prepared gas mixtures, UA [CO2] was altered without affecting alveolar or arterial PCO2. When the ponies were at a neut...
Hagedorn HW, Meiser H, Zankl H, Schulz R.Due to its tranquilizing properties, the tricyclic antidepressant doxepin may be misused as a doping agent in competition horses. Therefore, efficient analytical procedures are required to detect this drug in samples submitted for doping control. To screen for parent doxepin in equine blood and urine, a less specific method has been accepted employing gas chromatography (GC) combined with electron impact (EI) mass spectrometry (MS). The aim of this study was identification of doxepin metabolites providing more specific MS data to verify positives resulting from screening. Thus, after a horse w...
Davíðsson HB, Rees T, Ólafsdóttir MR, Einarsson H.Automated gait classification has traditionally been studied using horse-mounted sensors. However, smartphone-based sensors are more accessible, but the performance of gait classification models using data from such sensors has not been widely known or accessible. In this study, we performed horse gait classification using deep learning models and data from mobile phone sensors located in the rider's pocket. We gathered data from 17 horses and 14 riders. The data were gathered simultaneously from movement sensors in a mobile phone located in the rider's pocket and a gait classification system ...
Krueger K, Trager L, Farmer K, Byrne R.Tool use has not yet been confirmed in horses, mules or donkeys. As this subject is difficult to research with conventional methods, we used a crowdsourcing approach to gather data. We contacted equid owners and carers and asked them to report and video examples of "unusual" behaviour via a dedicated website. We also searched YouTube and Facebook for videos of equids showing tool use. From 635 reports, including 1014 behaviours, we found 20 cases of tool use, 13 of which were unambiguous in that it was clear that the behaviour was not trained, caused by reduced welfare, incidental or accidenta...
Ho EN, Kwok WH, Leung DK, Wan TS, Wong AS.Turinabol (4-chloro-17alpha-methyl-17beta-hydroxy-1,4-androstadien-3-one) is a synthetic oral anabolic androgenic steroid. As in the case of other anabolic steroids, it is a prohibited substance in equine sports. The metabolism of turinabol in human has been reported previously; however, little is known about its metabolic fate in horses. This paper describes the studies of both the in vitro and in vivo metabolism of turinabol in racehorses with an objective to identify the most appropriate target metabolites for detecting turinabol administration. For the in vitro studies, turinabol was incub...
Rahmanian MS, Thompson DL, Melrose PA.The ultrastructural and immunoreactive staining characteristics of cells containing prolactin (lactotropes) and growth hormone (GH; somatotropes) in the anterior pituitaries of gonadally intact pony mares were studied at the electron microscopic level. Lactotropes included two morphological subsets: Type I cells were larger and contained large, dense, polymorphic granules that were scattered throughout the cytoplasm; Type II cells were smaller and contained small, dense, polymorphic granules that were predominantly found in peripheral areas of the cytoplasm. Lactotropes constituted 5 to 16% of...
Treiber KH, Boston RC, Geor RJ, Hess TM, Harris PA, Kronfeld DS.Tools and criteria to evaluate and understand glucose metabolism are essential to optimise equine energy utilisation for exercise performance and reduced metabolic health risks. Objective: To re-evaluate models of glucose kinetics in the horse at rest and during endurance type exercise using a single injection technique and compartmental modelling. Methods: Twelve exercise trained Arabian geldings received a bolus of 100 µmol/kg bwt [6,6-(2) H]glucose i.v. while at rest and while running at ∼ 4 m/s on a treadmill. Tracer and tracee glucose curves from 4-150 min after the bolus dose (while t...
van Buiten A, Remmen JL, Colenbrander B.In horses reproductive performance is usually expressed as the foaling rate. This rate ranges from 40% to 80%. Three major factors contribute to this variation namely, the stallion, the mare and management. In this study, the performance of Shetland ponies kept in three different breeding systems was investigated retrospectively. In one breeding system, the stud farmer travelled with his stallion (n = 9) to the mare (system 1) while in another system, the stallion (n = 3) stayed at the stud farm and the mares came to the stallion (system 2). The last system was pasture breeding (system 3; n = ...
Steffey EP, Howland D.The minimal alveolar concentration (MAC) of halothane which just prevented purposeful movement in response to electrical stimulation was determined in 11 young, healthy, unpremedicated horses breathing oxygen (O2) or nitrous oxide (N2O) and O2. Ventilation was controlled during these MAC studies. The arterial PO2 was always greater than 90 mm of Hg and the average PaCO2. range was 36 to 40 mm of Hg. The MAC for halothane in O2 was 0.93 vol %. Alveolar N2O concentrations of 25% and 50% reduced the halothane MAC about 12% and 25%, respectively. In 8 of these horses, the cardiovascular effects of...
Rowlands IW.The world-wide foaling rate in the mare is low and in the Hannoverian breed has remained asymptotic at about 50 per cent for over 150 years. In an attempt to discover some of the possible reasons for this low fertility rate, the evolutionary history of the perissodactyls, the odd-toed ungulates, is reviewed here. Of the 156 genera of this order, 152 are in the fossil record; this gives them the highest extermination rate of all the mammal groups. Some of the unusual and unique features of the reproductive physiology of the mare and their possible association with low fertility are considered.
Webb PD.The pituitary glands of 4 horse embryos (41-55 days of gestation) were examined by light microscopy, and the pars distalis from 10 fetal foals (75-300 days) was examined by electron microscopy. At Day 41 the development of Rathke's pouch and the saccus infundibuli was advanced; the former had almost lost its connection with the stomodaeum and the latter had started to differentiate into infundibular process and infundibular stalk. By Day 43 Rathke's pouch was completely dissociated from the stomodaeum and its walls were beginning to show uneven growth. The ventral wall of the pouch, the future...
Mialhe PJ.In order to verify possible preferential prey selection by Desmodus rotundus feeding on domestic herbivores in the Municipality of São Pedro (São Paulo, Brazil), vampire bat attacks were surveyed at rural properties where domestic herbivores were being raised and attack frequencies of D. rotundus on the total herd and on different species were calculated. The analysis found that the most frequently attacked herbivores were cattle and horses. The chi-square test (χ2), with a significance level of 5% corroborated the comparative analysis of attack frequency in properties that had these two sp...
