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.
Asseged BD, Habtemariam T, Tameru B, Nganwa D.Deriving horse oocytes in the USA is hampered by the lack of abattoirs processing horse carcasses which could provide abundant quantities of ovaries from slaughtered mares. Therefore, several cloning industries in the USA are attempting to import cloned horse embryos from Canada. Like any agricultural commodity, cloned embryos pose a risk of introduction of exotic animal diseases into the importing country. Under such circumstances, risk assessment could provide an objective, transparent, and internationally accepted means for evaluating the risk. This quantitative risk assessment (QRA) was in...
Bailey CS, Sper RB, Schewmaker JL, Buchanan CN, Beachler TM, Pozor MA, Whitacre MD.The objective of this study was to use Doppler ultrasound technology to determine whether pentoxifylline administration increased uterine blood flow in normal pregnant pony mares. Thirteen pregnant pony mares between 18 and 190 d of gestation (mean ± SEM, 101 ± 55) were utilized for the study during two trial periods. In each trial, pentoxifylline (17 mg/kg by mouth every 12h, diluted in syrup) was administered to half of the mares for 3 d, while the other mares were treated with syrup only. Doppler measurements were obtained from the right and left uterine arteries from each mare for 2 d pr...
Walter J, Klein C, Wehrend A.Mast cells constitute part of the cellular immune system of the genital tract. They play a potential role in cervical remodelling during parturition and are subject to the influence of ovarian steroids. In this study, the influence of oestradiol-17β and progesterone on the distribution of mast cells in equine vaginal, cervical and uterine tissue was evaluated. Genital tracts were retrieved from healthy mares at a local slaughterhouse. The cervix was divided along the longitudinal axis into five equivalent regions from cranial to caudal (R1 to R5). Toluidine blue staining was used for the dete...
Wilsher S, Lefranc AC, Allen WR.During embryo transfer (ET) the equine embryo can tolerate a wide degree of negative asynchrony but positive asynchrony of >2 days usually results in embryonic death. There is still confusion over whether this is due to the inability of the embryo to induce luteostasis or to an inappropriate uterine environment. Objective: To assess embryo survival and development in an advanced uterine environment. Objective: Embryo-uterine asynchrony, not the embryo's inability to induce luteostasis, is responsible for embryonic death in recipient mares with a >2 days chronologically advanced uterus. Methods...
Albertsdóttir E, Arnason T, Eriksson S, Sigurdsson A, Fikse WF.The genetic evaluation of Icelandic horses is currently based on results from breeding field tests of riding ability and conformation. The effect of integrating competition traits and/or test status into the genetic evaluation was studied concerning estimation bias, predictive ability, accuracy, correlations between breeding values and ranking of sires. Breeding field test data included 19 954 records from horses assessed in 11 countries during 1994-2008. Competition data included 44 160 records from 7687 horses competing in Iceland and Sweden in 1998-2008. Test status was defined as attendanc...
Smits K, Govaere J, Hoogewijs M, Piepers S, Van Soom A.Intracytoplasmic sperm injection (ICSI) is the method of choice for the in vitro production (IVP) of equine embryos. However, conventional ICSI has been associated with mechanical damage to the oocyte caused by the deformation of the zona pellucida (ZP) and exposure of the oolemma to negative pressure during injection. Introduction of the less traumatic and more efficient piezo drill-assisted ICSI (PDAI) yielded higher cleavage rates and more consistent results. Nevertheless, PDAI is also associated with disadvantages such as the use of mercury and possible DNA damage. This led us to explore a...
Fowlie J, Arnoczky S, Lavagnino M, Maerz T, Stick J.To evaluate the magnitude and distribution of joint contact pressure on the medial tibial condyle after grade III cranial horn tears of the medial meniscus. Methods: Experimental study. Methods: Cadaveric equine stifles (n = 6). Methods: Cadaveric stifles were mounted in a materials testing system and electronic pressure sensors were placed between the medial tibial condyle and medial meniscus. Specimens were loaded parallel to the longitudinal axis of the tibia to 1800 N at 130°, 140°, 150°, and 160° stifle angle. Peak pressure and contact area were recorded from the contact maps. Testing...
Böer U, Lohrenz A, Klingenberg M, Pich A, Haverich A, Wilhelmi M.Decellularized equine carotid arteries (dEAC) may represent a reasonable alternative to alloplastic materials in vascular replacement therapy. Acellularity of the matrix is standardly evaluated by DNA quantification what however may not record sufficiently the degree of matrix immunogenicity. Thus, our aim was to analyze dEAC with a low DNA content for residual cellular proteins. A detergent-based decellularization protocol including endonuclease treatment resulted in dEAC with 0.6 ± 0.15 ng DNA/mg dry weight representing 0.33 ± 0.14% of native tissue DNA content. In contrast, when matrices ...
Jackson M, Vizard A, Anderson G, Clarke A, Whitton R.OBJECTIVES Describe the association between the purchase price of Thoroughbred yearlings sold in Australia and racing performance as 2- and 3-year-olds. METHODS Race performance data of 2773 Thoroughbred yearlings sold at auction during 2003 were collected. Associations between purchase price and the probability of starting, the number of race starts and the prize money earned were examined. RESULTS In total, 2206 (79.6%) horses started a race. The mean number of race starts was six and the mean prize money earned was A$24,420. A total of 1711 (61.5%) horses earned prize money, 402 (14.4%) ear...
Lewis NS, Daly JM, Russell CA, Horton DL, Skepner E, Bryant NA, Burke DF, Rash AS, Wood JL, Chambers TM, Fouchier RA, Mumford JA, Elton DM, Smith DJ.Equine influenza virus is a major respiratory pathogen in horses, and outbreaks of disease often lead to substantial disruption to and economic losses for equestrian industries. The hemagglutinin (HA) protein is of key importance in the control of equine influenza because HA is the primary target of the protective immune response and the main component of currently licensed influenza vaccines. However, the influenza virus HA protein changes over time, a process called antigenic drift, and vaccine strains must be updated to remain effective. Antigenic drift is assessed primarily by the hemagglu...
Eivers SS, McGivney BA, Gu J, MacHugh DE, Katz LM, Hill EW.Peroxisome proliferator-activated receptor-γ coactivator 1α (PGC-1α) has emerged as a critical control factor in skeletal muscle adaptation to exercise, acting via transcriptional control of genes responsible for angiogenesis, fatty acid oxidation, oxidative phosphorylation, mitochondrial biogenesis and muscle fibre type composition. In a previous study, we demonstrated a significant increase in mRNA expression for the gene encoding PGC-1α (PPARGC1A) in Thoroughbred horse skeletal muscle following a single bout of endurance exercise. In this study, we investigated mRNA expression changes i...
Armentrout AR, Beard WL, White BJ, Lillich JD.The flexion test is routinely used in lameness and prepurchase examinations. There is no accepted standard for duration of flexion or evidence that interpretation of results would differ with different durations of flexion. Objective: There will be no difference in interpretation of proximal hindlimb flexion for 5 or 60 s. Methods: Video recordings of lameness examinations of 34 client-owned horses were performed that included: baseline lameness, proximal hindlimb flexion for 60 s, and flexion of the same limb for 5 s. Videos were edited to blind reviewers to the hypothesis being tested. The b...
Corbin LJ, Blott SC, Swinburne JE, Vaudin M, Bishop SC, Woolliams JA.We have used linkage disequilibrium (LD) to identify single nucleotide polymorphisms (SNPs) on the Illumina Equine SNP50 BeadChip, which may be incorrectly positioned on the genome map. A total of 1201 Thoroughbred horses were genotyped using the Illumina Equine SNP50 BeadChip. LD was evaluated in a pairwise fashion between all autosomal SNPs, both within and across chromosomes. Filters were then applied to the data, firstly to identify SNPs that may have been mapped to the wrong chromosome and secondly to identify SNPs that may have been incorrectly positioned within chromosomes. We identifie...
Pillet E, Labbe C, Batellier F, Duchamp G, Beaumal V, Anton M, Desherces S, Schmitt E, Magistrini M.Egg yolk is normally used as a protective agent to freeze semen of equine and other species. However, addition of egg yolk in extenders is not without disadvantages and the demand to find cryoprotective alternatives is strong. The objective of this study was to test the cryoprotective capacities of liposomes composed of egg yolk phospholipids. Two experiments were conducted: 1) the first to determine the optimal composition and concentration of liposomes to preserve post-thaw motility and membrane integrity of spermatozoa; 2) the second to assess in vivo the cryoprotective capacities of these ...
Pollina GF, Zagotto G, Maritan P, Iacopetti I, Busetto R.Gallium (Ga), a metal in group IIIA of the periodic table, has shown a remarkable activity against bone resorption and could therefore possibly prove useful in the treatment of certain diseases in sport horses, for example navicular disease. The aim of this study was to gain more information concerning the kinetics of Ga after oral administration of gallium nitrate (GaN) in adult horses. Six horses received a single dose of 10 mg/kg of GaN mixed with the food ration. Absorption was slow (T(max) = 10 ± 3 h, T(½abs) = 2 ± 0.8 h), and a C(max) of 26 ± 11 μg/L was achieved. Excretion followed...
Schmidburg I, Pagger H, Zsoldos RR, Mehnen J, Peham C, Licka TF.Laterolateral radiographs of equine necks are reported to be inaccurate in determining the site of spinal cord lesions even when a myelogram is carried out. The goal of this study was to assess constrictions present in the cervical vertebral canal at any time point throughout the extremes of movement. Sixteen equine cervical vertebral columns without history of cervical disease were used. After removal of the spinal cord, the dura mater was filled with polyurethane foam and during its plastic phase the cervical vertebral column was passively moved in flexion-extension, lateral bending and 30°...
The Journal of hereditySeptember 13, 2011
Volume 102, Issue 6 753-758 doi: 10.1093/jhered/esr091
Guastella AM, Zuccaro A, Criscione A, Marletta D, Bordonaro S.Genetic diversity and relationship among 3 Sicilian horse breeds were investigated using 16 microsatellite markers and a 397-bp length mitochondrial D-loop sequence. The analysis of autosomal DNA was performed on 191 horses (80 Siciliano [SIC], 61 Sanfratellano [SAN], and 50 Sicilian Oriental Purebred [SOP]). SIC and SAN breeds were notably higher in genetic variability than the SOP. Genetic distances and cluster analysis showed a close relationship between SIC and SAN breeds, as expected according to the breeds' history. Sequencing of hypervariable mitochondrial DNA region was performed on a ...
Coli A, Nocchi F, Lamanna R, Iorio M, Lapi S, Urciuoli P, Scatena F, Giannessi E, Stornelli MR, Passeri S.The amnion is a particular tissue whose cells show features of multipotent stem cells proposed for use in cellular therapy and regenerative medicine. From equine amnion collected after the foal birth we have isolated MSCs (mesenchymal stem cells), namely EAMSCs (equine amnion mesenchymal stem cells), from the mesoblastic layer. The cells were grown in α-MEM (α-modified minimum essential medium) and the effect of EGF (epidermal growth factor) supplementation was evaluated. To assess the growth kinetic of EAMSCs we have taken into account some parameters [PD (population doubling), fold increas...
Rendo F, Iriondo M, Manzano C, Estonba A.Here, we present the results of a genetic analysis of 463 Pottoka ponies corresponding to four generations, using 17 microsatellite markers. Ten years after the beginning of the Pottoka conservation programme, the values for the genetic diversity of the breed are still high and stable, indicating the success of the programme. We found null alleles in Pottoka for the ASB23, HMS3 and HTG10 microsatellites. Together with information obtained from other pony breeds from the Iberian Peninsula, this finding indicates that these microsatellites should not be used for phylogenetic analyses or parentag...
Ginther OJ.One of the most profound theriogenology applications of transrectal diagnostic ultrasonography in mares involves the imaging of ovarian follicles and corpora lutea. The resolving capabilities (frequency) and quality of the scanner directly affect the minimal size of a structure that can be imaged and the quality of the image. High-frequency scanners (5 or 7.5 MHz) of good quality can image a 2-mm follicle and the corpus luteum throughout its functional life. A low-frequency scanner (3 or 3.5 MHz) can image a 6-mm follicle and the corpus luteum for several days after ovulation. Equine follicles...
Art T, Desmecht D, Amory H, Lekeux P.The aim of the present experiment was to investigate the hypothesis that there is a respiration-locomotion coupling in trotting equines. Therefore the respiratory airflow (V), the gastric pressure (Pga) and pleural pressure (Ppl) changes and the step frequency (SF) were simultaneously recorded in 5 trotting ponies (body weight: 255 +/- 15 kg; age: 3.5 +/- 0.4 years). Airflow was measured using a Fleisch pneumotachograph fixed on a face mask. Esophageal and gastric balloon catheters coupled to pressure transducers allowed the recording of Ppl and Pga. The exercise was performed on a treadmill a...
Updike SJ.Equine tarsocrural collateral ligaments (CL) were dissected grossly. The areas of attachment and fiber arrangements were described for the long lateral CL, long medial CL, 3 short lateral CL, and 3 short medial CL. Sequential cutting of CL in any order indicated that the short medial CL were responsible for the snap-joint phenomenon observed at the equine tarsocrural joint.
Kriz NG, Rose RJ.To assess the repeatability of commonly employed transthoracic echocardiographic measurements in standing horses. Methods: Thirteen healthy 3- to 4-year-old fit Standardbred geldings with a mean weight of 411 (SEM +/- 10) kg were studied. The horses' environment, feeding and management regimens were standardised. All measurements were performed by the same investigator at the same time every day for three consecutive days. Methods: Standard transthoracic measurements were made on all horses. Each measurement was performed over three consecutive cardiac cycles on 1 day and all measurements were...
Lindinger MI, Ecker GL.Horses lose considerably more electrolytes through sweating during prolonged exercise than can be readily replaced through feeds. The present study tested an oral electrolyte supplement (ES) designed to replace sweat electrolyte losses. We measured gastric emptying of 3 litres of ES (using gamma imaging of (99)Tc-sulfide colloid), the absorption of Na(+) and K(+) from the gastrointestinal tract using (24)Na(+) and (42)K(+), and the distribution of these ions in the body by measuring radioactivity within plasma and sweat during exercise. Three litres of ES emptied from the stomach as fast as wa...
Kronfeld DS, Holland JL, Rich GA, Meacham TN, Fontenot JP, Sklan DJ, Harris PA.The digestibility of ether extract varies greatly from forages to grains and further to added fats consisting mainly of triglycerides. This variation has been attributed to two main factors, the presence of nonhydrolyzable substances in the ether extract, especially in leafy foods, and the dilution of endogenous fecal fat. A compilation of results from 188 equine digestion balance observations on five basal feeds and 18 test feeds with added fats demonstrated a true digestibility of fat approaching 100% and an endogenous fecal fat of 0.22 g x d(-1) x kg BW(-1). The results revealed that nonhyd...
Schryver HF, Craig PH, Hintz HF.Calcium metabolism of young, growing ponies fed diets containing 1.5, 0.8 and 0.15% calcium was studied using combined balance and kinetic methods. Variations in calcium intake produced large differences in excretion and retention but had no effect on the level of plasma calcium or on the size of the exchangeable pool. Intestinal absorption, renal excretion and calcium removal from bone responded to the dietary level of calcium to maintain calcium homeostasis. The rates of intestinal absorption and the removal of calcium from the skeleton increased while renal excretion decreased in response t...
Richards CM, Aucken HA, Tucker EM, Hannant D, Mumford JA, Powell JR.Studies were carried out to determine the optimum conditions for the production of equine monoclonal antibodies (MAbs). Lymphocytes from ponies immunised with influenza A equine 2 virus, isolate A/Equine/Newmarket/79 (H3N8) were fused with mouse myeloma (NSO) cells and with horse-mouse heterohybridomas made aminopterin-sensitive by selective growth in 8-azaguanine. Although all fusions initially resulted in heterohybridoma colonies that secreted equine immunoglobulin, many of these were unable to maintain secretion for longer than a few weeks. Increasing the time between immunisation and the b...
Baxter GM, Morrison S.The most common and significant complication of excessive unilateral weight bearing in adult horses is support limb laminitis. Young horses with unilateral lameness problems develop support limb laminitis infrequently compared with adult horses.
Khalil AM, Murakami N.For the past 12 years, a study was conducted in the Misaki area (southern Kyushu Island, Japan) to investigate young males form new harems, how they acquire the mares and the factors affecting the process of new harem formation. Young males formed new harems between the ages of 3.8 and 7.6 yr, and 93% of these new harem groups were formed at the beginning of the breeding season. The most common way (87%) for young males to form a new harem was by acquiring wandering mares which had separated from their groups, whereas 13% stole unstable mares from established bands. The fact that all young mal...
Schams D, Papkoff H.Highly purified pregnant mare serum gonadotropin (PMSG) can be prepared from crude commercial preparations of PMSG by chromatography on sulfoethyl-Sephadex C-50 and gel filtration on Sephadex G-100. The preparation was examined by disc electrophoresis and gel filtration and found to be of high purity. Amino acid analysis shows similarities to pituitary gonadotropins. The PMSG contains a high content of proline and cystine and low amounts of the aromatic amino acids. Phenylalanine is the major amino terminal amino acid. The carbohydrate content totals 45% of which 10% is the content of sialic a...
Weiss DJ, Evanson OA, Fagliari JJ, Valberg S.To determine whether platelets become activated and form platelet-neutrophil aggregates during near-maximal treadmill exercise in horses. Methods: 4 Thoroughbreds. Methods: Horses were subjected to 4 standardized exercise tests on a treadmill, and blood samples were collected before exercise, at treadmill speed of 12 m/s, and 5 minutes after exercise. Flow cytometric techniques were used to identify activated platelets, and flow cytometric and microscopic techniques were used to identify platelet-neutrophil aggregates. Results: Platelet-neutrophil aggregates increased from 2.8 +/- 0.4% at rest...
Wentink GH.The dynamics of the hind limbs of the horse and dog at walk are compared. The kinematics were studied by electromyography of animals walking on a moving belt, and by cinephotography in horses walking on the ground and in dogs walking on a moving belt and on the ground.
This study reveals that: 1) the retraction of the hoof or foot relative to the hip at the end of the support phase is less in the horse than in the dog; 2) the change in the sense of the movements of the hind limb segments at the end of the support phase and at the beginning of the swing phase occurs earlier in the horse (55â...
Galera PD, Brooks DE.Keratomycosis in the horse exists in several unique clinical forms. This paper discusses the diagnosis and clinical management of keratomycosis in the horse associated with tear film instability, epithelial keratopathy, subepithelial infiltrates, superficial and deep ulcers, plaques, melting ulcers, descemetoceles, iris prolapse, and stromal abscesses. Prompt diagnosis and aggressive treatment of equine keratomycosis can make a major difference in the maintenance of a cosmetic and visual eye.
Bracun A, Ellis AD, Hall C.Ophthalmic examination in the horse is generally limited to crude assessment of vision and screening for ocular lesions. The refractive state of equine eyes and the potential impact on vision and performance requires further investigation. Objective: To assess the refractive state of a large, mixed-breed sample of horses and ponies in the United Kingdom (UK). Methods: The refractive state of both eyes of 333 horses and ponies was determined by streak retinoscopy, and the effect of age, height, gender, breed and management regime on the refractive state assessed. Results: Emmetropia was found i...
Rapin V, Poncet PA, Burger D, Mermod C, Richard MA.A study carried out on 49 horses showed that it is possible to measure the attention time by operant conditioning. After teaching horses an instrumental task using a signal, we were then able to test their attention time by asking them to prolong it increasingly while setting success and failure criteria. Two tests were performed 3 weeks apart. The 2nd test was feasible without relearning, a proof of memory, and was repeatable, a proof of consistency in the attention time. A significant difference was observed between the 3 age groups. Young horses often performed very well during the 1st test...
Walker VA, Dyson SJ, Murray RC.Development of core muscle strength is important for training and during rehabilitation following injury. A Pessoa training aid (PTA) is a system of ropes and pulleys which is commonly used during equine training and rehabilitation, but there is limited information on its effectiveness. The objective of the study was to determine the effect of the PTA on the temporal, linear and angular kinematics of the working trot. Influence of testing order on effect of a PTA was assessed in four horses. Twelve riding horses were lunged at working trot on a 16 m diameter circle without (WO) and with a PTA ...