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.
Donadeu FX, Watson ED.The annual reproductive cycle in the horse involves a reduction in ovarian activity during short days. The absence of ovulatory activity during winter has important consequences for an equine industry eager to breed mares early during the year. The anovulatory season results from a reduction in the secretion of pituitary gonadotropin that is in turn triggered by the inhibitory effects of short photoperiod on the hypothalamus-pituitary axis. Recent studies have provided evidence that the response of the ovaries to endocrine stimuli during the anovulatory season is affected not only by circulati...
Murphy BA, Vick MM, Sessions DR, Cook RF, Fitzgerald BP.Peripheral clocks receive timing signals from the master mammalian pacemaker in the suprachiasmatic nucleus (SCN) and function to adaptively anticipate daily changes that influence local physiology. Evidence suggests that peripheral immune activation may act as a resetting signal for circadian clocks in peripheral tissues. We wished to investigate whether acute systemic inflammation could synchronize clock gene expression in equine peripheral blood, a tissue that does not normally oscillate in this species. We report that in vivo administration of lipopolysaccharide (LPS) results in significan...
Ahmed YA, Tatarczuch L, Pagel CN, Davies HM, Mirams M, Mackie EJ.Post-proliferative chondrocytes in growth cartilage are present in two forms, light and dark cells. These cells undergo hypertrophy and die by a mechanism that is morphologically distinct from apoptosis, but has not been characterized. The aims of the current study were to document the ultrastructural appearance of dying hypertrophic chondrocytes, and to establish a culture system in which the mechanism of their death can be examined. Methods: Growth cartilage from fetal and growing postnatal horses was examined by electron microscopy. Chondrocytes were isolated from epiphyseal cartilage from ...
Zarucco L, Wisner ER, Swanstrom MD, Stover SM.Biomechanical models that compute the lengths and forces of muscle-tendon units are broadly applicable to the study of factors that promote injury and the planning and effects of orthopedic surgical procedures in equine athletes. A three-dimensional (3D) generic musculoskeletal model of the equine forelimb comprised of bony segment, muscle-tendon, and ligament information, was developed based on high-resolution computed tomographic (CT) and T1-weighted magnetic resonance (MR) images from an isolated forelimb of a Thoroughbred racehorse. Image fusion was achieved through coregistration of CT an...
Deeg CA, Amann B, Hauck SM, Kaspers B.The major cell types in the mammalian retina are photoreceptors, amacrine, horizontal, bipolar, ganglion and Mueller glial cells. Most of the specific cell types are conserved, but cytochemical markers vary between species. The aim of our study was to characterize cytochemically distinctive markers for different cell types in the equine retina. We were able to define specific markers for equine Mueller glial cells and photoreceptor cells. Furthermore, we describe markers for large ganglion cells, horizontal and amacrine cells and a subpopulation of bipolar cells. Additionally, discrimination b...
McGreevy PD.The lengthy association of humans with horses has established traditional equestrian techniques that have served military and transport needs well. Although effective, these techniques have by-passed the research findings of modern psychologists, who developed the fundamentals of learning theory. That said, the pools of equestrian debate are far from stagnant. The latest wave of horse whisperers has offered some refinements and some novel interpretations of the motivation of horses undergoing training. Additionally, the Fédération Equestre Internationale (FEI) has introduced the concept of t...
Poulet H, Minke J, Pardo MC, Juillard V, Nordgren B, Audonnet JC.The canarypox vaccine vector (ALVAC) technology has been used to develop and license several vaccines for companion animals and horses in the European Union and USA. ALVAC is a ubiquitous vector with high biosafety since it is non-replicative in mammalians, is genetically and physically stable, and able to induce both humoral and cell-mediated immune responses against the expressed transgene product. Specific rules apply for the development and registration of recombinant vector vaccines. The biology of the vector as well as the recombinant virus must be thoroughly documented to allow the risk...
Mitchell G, Fuller A, Maloney SK, Rump N, Mitchell D.Selective brain cooling (SBC) is defined as the lowering of brain temperature below arterial blood temperature. Artiodactyls employ a carotid rete, an anatomical heat exchanger, to cool arterial blood shortly before it enters the brain. The survival advantage of this anatomy traditionally is believed to be a protection of brain tissue from heat injury, especially during exercise. Perissodactyls such as horses do not possess a carotid rete, and it has been proposed that their guttural pouches serve the heat-exchange function of the carotid rete by cooling the blood that traverses them, thus pro...
Kornilova OA.Endobiotic ciliates of native Yakut horse are investigated. 57 ciliate species have been found. From 17 up to 43 species of ciliates have been revealed in each host specimen. The specimens of Alloiozona trizona Hsiung, 1930 and Triadinium caudatum Fiorentini, 1890 were present in 100 % of the horses. The endemic genus and species of allantosomides, Strelkowella urunbasiensis Kornilova, 2004, has been found in 11 horses. Allantoxena japonensis (Imai, 1979) and Cycloposthium ishikawai Gassovsky, 1919 being recorded previously in Japan only were found for the first time in Russia. The species Cyc...
Bidwell LA, Bowker RM.To evaluate morphologic changes of the stratum internum of hooves from near-term fetal, newborn, and yearling horses. Methods: Feet from 27 near-term equine fetuses, 19 newborn foals, and 8 yearlings. Methods: Primary epidermal laminae (PEL) of the stratum internum were examined for evidence of architectural changes. Results: In near-term fetuses, the PEL had a homogeneous appearance and symmetric distribution around the hoof wall with no significant differences in PEL density between the toe and quarters. However after birth, branched laminae at the toe formed within the first few weeks, whic...
Yuan Z, Gallagher A, Gault EA, Campo MS, Nasir L.Bovine papillomavirus (BPV) type 2 is involved in carcinogenesis of the urinary bladder in cattle, while BPV-1 is commonly associated with equine sarcoid tumours. In both cases the early viral proteins are expressed, but virion is not produced. Given the similarities in BPV biology between the tumours in cattle and horses, bovine bladder cancers and equine sarcoids were compared with respect to physical status, load of viral DNA and variability of the E5 open reading frame (ORF). Rolling circle amplification demonstrated that BPV-1 and BPV-2 genomes exist as double stranded, episomal, circular...
Masset A, Staszyk C, Gasse H.Corrosion casts of blood vessels in the periodontium of cheek teeth from eight horses were observed three-dimensionally with a dissection microscope. Selected specimens were examined in a scanning electron microscope. Periodontal blood vessels communicated with those from the gingiva, the alveolar bone, and the apical region. In the upper jaw, there were anastomoses with the blood vessels of the mucosa of the maxillary sinus. The periodontal vascular system was organized in two or three layers. The peripheral layer was mainly composed of large venules, the inner one consisted of capillaries. I...
Masset A, Staszyk C, Gasse H.The micro-vasculature of the equine periodontal ligament (PDL) was investigated using corrosion casts for scanning electron microscopy. Specimens from eight healthy warm-blooded horses were examined. Specific vascular features such as large ampullae with a diameter of up to 300 microm and blind vascular casts were found in the specimens of the equine PDL. The ampullae-shaped venules occurred only in the peripheral layer, where they were formed at the confluence of several vessels. Two types of blind stumps were identified. The first was developed in all three layers, while the second was found...
Lefrançois T, Blitvich BJ, Pradel J, Molia S, Vachiéry N, Martinez D.In July 2002, a surveillance system was implemented on Guadeloupe to detect for the potential introduction and monitor the spread of West Nile virus (WNV). From 2002 to 2004, equines and chickens were serologically assayed for antibodies to WNV by IgG and IgM enzyme-linked immunosorbent assay (ELISA), epitope-blocking ELISA, and plaque reduction neutralization tests. After introduction, probably through migratory birds at the end of 2001, many seroconversions occurred between July and October 2002 resulting in a high seroprevalence (19.3%) in equines in 2003. WNV circulation levels decreased d...
Nakagawa K, Tokushima A, Fujiwara K, Ikeguchi M.The secondary structure in the molten globule state (an equilibrium analogue of a burst-phase folding intermediate) of equine beta-lactoglobulin was investigated by changes in the circular dichroic spectrum induced by a series of site-directed proline substitutions. The results challenge the structural picture obtained from previous hydrogen/deuterium exchange experiments. A stable non-native alpha-helix was found to exist in the region corresponding to the eighth strand (H strand) in the native structure, where the backbone amide protons are the most strongly protected from exchange. Therefor...
Kuehn R, Kaczensky P, Lkhagvasuren D, Pietsch S, Walzer C.Recent studies suggest that Asiatic wild asses (Equus hemionus) are being increasingly poached in a commercial fashion. Part of the meat is believed to reach the meat markets in the capital Ulaanbaatar. To test this hypothesis, we collected 500 meat samples between February and May 2006. To differentiate between domestic horse (Equus caballus) and wild ass meat, we developed a restriction fragment length polymorphism (RFLP) assay based on the polymerase chain reaction (PCR). We amplified and sequenced a cytochrome b fragment (335 bp) and carried out a multialignment of the generated sequences ...
Loomis PR.Clinical reproduction in the horse more closely parallels human clinical reproduction than in other domestic farm animals. Horse breeders rarely include fertility as a selection criterion when making mating decisions; in most breeds, there is no licensing or approval of stallions. This has led to a significant number of stallions in the breeding pool that possess desirable performance traits but are subfertile for a variety of reasons, some of them genetically transmitted between generations. Therefore, semen characteristics can vary greatly among stallions within the breeding population. A ch...
Macpherson ML.Equine placentitis is a complex disease that has devastating consequences for horse owners. Placentitis is a significant cause of foal loss annually. Prompt diagnosis and treatment of the disease are paramount for survival of the affected neonate. This article discusses current information on pathogenesis of the disease as well as diagnostic and therapeutic options.
Hinrichs K.Equine cloning is now in use as a clinical technique. It is available commercially, and its efficiency seems to be increasing. The foals produced by cloning may differ in some phenotypic and behavioral traits from the original animal but should produce offspring that reflect those that the original donor animal would have produced. This is especially true in the case of male animals, where the mitochondrial DNA is not passed to the progeny. Results of pregnancies due in 2006 should add significantly to our understanding of the factors affecting production of viable cloned foals and of the simi...
Morris L.Advanced artificial insemination techniques, such as deep uterine,hysteroscopic, oviductal, and intrafollicular insemination, are described in the context of the different types of spermatozoa that are now available for insemination, including fresh, chilled, frozen,sex-sorted, and epididymal spermatozoa. The implementation of these new technologies answers and poses questions about the interactions of sperm and oocytes in vivo.
Carnevale EM.Vitrification can be used successfully to cryopreserve equine embryos. Embryos for vitrification should be collected from donor mares' uteri when they are 300 mm or less in diameter, however,and at the morula or early blastocyst stage of development. No special equipment is required for vitrification; the straw containing the embryo is exposed to vapor for 1 minute before plunging it into liquid nitrogen. Warming of the straw requires no special equipment,and the embryo can be transferred directly from the straw into a recipient's uterus. Vitrification has been repeatedly successful when the p...
Yuan Z, Philbey AW, Gault EA, Campo MS, Nasir L.Papillomaviruses are normally strictly species-specific and even under experimental conditions do not usually infect any other host than the natural host. The only documented reports of natural papillomavirus cross-species infection are of BPV-1/BPV-2, which can infect horses and induce equine sarcoids. BPV DNA has not been detected in non-sarcoid equine tumours or equine papillomas, but its presence has been reported in some cases of equine dermatitis. In the present study, we show that equine inflammatory skin conditions harbour episomal circular double stranded BPV-1 genomes, with copy numb...
Vanderwall DK.Tremendous progress has been made in the development of assisted reproductive techniques that may enhance the reproductive efficiency of the horse. However, techniques that involve the manipulation of oocytes and/or embryos may themselves be detrimental to embryo viability and subsequent development. Therefore, an objective method of assessing viability of embryos before and/or after oocyte/embryo manipulation is desirable. At this time, morphologic evaluation is the most widely used method of determining the viability of equine embryos. Although morphologic assessment of embryo quality will n...
Hunter JO.Irritable bowel syndrome (IBS) in man is not a single entity but has several causes. One of the most common forms has similarities with colic and laminitis in horses. Undigested food residues may pass from the small intestine into the colon where bacterial fermentation produces chemicals that lead to disease. In horses the consequences may be disastrous, but in healthy humans such malabsorption may not be harmful. After events such as bacterial gastroenteritis or antibiotic treatment, an imbalance of the colonic microflora with overgrowth of facultative anaerobes may arise, leading to malferme...
Simonato SP, Bernardina GRD, Ferreira LCR, Silvatti AP, Barcelos KMC, da Fonseca BPA.This study aimed to provide a preliminary description of the sagittal and transverse plane kinematics of the thoracolumbar spine of Mangalarga Marchador (MM) horses performing the marcha batida gait, led in-hand. We evaluated the pattern of angular movement and the mean amplitude of six specific angles. An optoelectronic system was used for 3D kinematic analysis (19 cameras, 250 Hz). They were positioned around the horses and an acquisition volume of 16 × 4.8 × 3 meters was used. Eight retroreflective markers were fixed on the spine of the animals over thoracic vertebrae 8 (T8), 12 (T12), 15...
Denny HR.Brucella abortus infection in horses is important not only as a clinical entity but also as a potential source of infection for man and other animals. A review of the current knowledge of this disease in the horses is therefore thought to be useful. The incidence of infection in horses has been the subject of many surveys. Most authors used the serum agglutination test as an indication of infection. The majority of surveys were carried out in about 1930 and these showed a wide range in the proportion of positive reactors from 0.5 to 40 percent. Several factors would account for this: variation...
Kowalczyk K, Frąckowiak H.Considerable consistency in the arterial pattern of the head has been observed in species of Artiodactyla, but few studies have examined the order Perissodactyla. Here, we describe arteries supplying the intermandibular, mental, masseteric, buccal, labial, and nasal regions in eight perissodactylans, including representing of all families comprising this order. Observations were made on a total of 45 preparations of head arteries, obtained by injection of arteries with acetone-dissolved stained vinyl superchloride or stained latex LBS3060. In the Equidae species alone it was found that the fac...
Pollock S, Stover SM, Hull ML, Galuppo LD.The first objective of this study was to experimentally determine surface bone strain magnitudes and directions at the donor site for bone grafts, the site predisposed to stress fracture, the medial and cranial aspects of the transverse cross section corresponding to the stress fracture site, and the middle of the diaphysis of the humerus of a simplified in vitro laboratory preparation. The second objective was to determine whether computing strains solely in the direction of the longitudinal axis of the humerus in the mathematical model was inherently limited by comparing the strains measured...
Jeppesen A, Eyers R, Evans D, Ward MP, Quain A.Jumps racing is a form of Thoroughbred horse racing that involves hurdles and steeples and typically longer distances, and heavier weights compared with flat racing, which does not incorporate obstacles. In Australia, jumps racing is carried out only in Victoria, one of eight states and territories. The continuation of jumps racing is contentious due to the higher risk of fatalities, falls and injuries for horses, compared with flat racing. While measures have been introduced by the industry to improve the safety of riders and horses, the rates of fatalities, falls and injuries in horses parti...
Yu NH, Ho EN, Tang FP, Wan TS, Wong AS.A multi-target high-throughput liquid chromatography-tandem mass spectrometry (LC-MS-MS) method for the detection of low ppt to low ppb levels of anabolic steroids, corticosteroids, anti-diabetics, and non-steroidal anti-inflammatory drugs (NSAIDs) in equine plasma was developed for the purpose of doping control. Plasma samples were first deproteinated by addition of trichloroacetic acid. Drugs were then extracted by solid-phase extraction (SPE) using Bond Elut Certify cartridges, and the extracts were analysed by a triple-quadrupole/linear ion trap LC-MS-MS instrument in positive electrospray...
The increasing interest in the study of spontaneous (SY) and contagious yawning (CY) was so far focused on several taxa, especially primates. Here, we focused on SY and CY in horses, a suitable species due to their complex social dynamics that has been largely overlooked in research on these phenomena. By analyzing videos of 48 horses on pasture, we identified 2 yawning morphologies: Covered ( ) and Uncovered Teeth ( ). Using EquiFACS, we quantitatively demonstrated that and differ in terms of muscle recruitment. Moreover, we provide the first evidence for the presence of CY by comparing 2...
Loftus L, Asher L, Leach M.Over the last twenty years the definition of good animal welfare has advanced from the 'absence of negative welfare states' to the aim of identifying the presence of positive welfare states; however, research on positive animal welfare is relatively new. Consequently, through expert consultation, this study aimed to synthesise knowledge regarding domesticated equine emotional state, specifically methods to induce and measure positive affective states, which could be of significant benefit to equine welfare across sectors. A Delphi consultation of experts in the field of equine behaviour, welfa...
Hayden SS, Blanchard TL, Brinsko SP, Varner DD, Hinrichs K, Love CC.Placement of sperm deep in the equine uterine horn allows fewer sperm to be inseminated while maintaining acceptable fertility, and has been promoted for use in circumstances when fertility would be expected to be low if standard insemination were used (e.g., semen from a subfertile stallion, or frozen-thawed semen). Two main techniques, transrectally guided (TRG) and hysteroscopic (HYS) insemination, have been developed for this purpose; however, there is some controversy regarding their comparative efficacy. This study was conducted to compare pregnancy rates when mares were inseminated by T...
Hall CA, Cassaday HJ, Vincent CJ, Derrington AM.Six horses (Equus caballus) were trained to discriminate color from grays in a counterbalanced sequence in which lightness cues were irrelevant. Subsequently, the pretrained colors were presented in a different sequence. Two sets of novel colors paired with novel grays were also tested. Performance was just as good in these transfer tests. Once the horse had learned to select the chromatic from the achromatic stimulus, regardless of the specific color, they were immediately able to apply this rule to novel stimuli. In terms of the underlying visual mechanisms, the present study showed for the ...
Medica AJ, Gibb Z, Sheridan A, Harrison N, Aitken RJ.MTT is a commonly used cell vitality probe, due to its ability to form insoluble formazan deposits at cellular locations of intense oxidoreductase activity. Although this response is considered a reflection of mitochondrial redox activity, extra-mitochondrial sites of MTT reduction have been recognized within the spermatozoa of several mammalian species. Therefore, the aim of this study was to determine the major sites and causative mechanisms of MTT reduction in stallion spermatozoa. Our results show that stallion spermatozoa displayed substantial mitochondrial formazan deposition, as well as...
Lieto LD, Cothran EG.Epitheliogenesis imperfecta (EI) is a hereditary junctional mechanobullous disease that occurs in newborn American Saddlebred foals. The pathological signs of epitheliogenesis imperfecta closely match a similar disease in humans known as Herlitz junctional epidermolysis bullosa, which is caused by a mutation in one of the genes (LAMA3, LAMB3 and LAMC2) coding for the subunits of the laminin 5 protein (laminin alpha3, laminin beta3 and laminin gamma2). The LAMA3 gene has been assigned to equine chromosome 8 and LAMB3 and LAMC2 have been mapped to equine chromosome 5. Linkage disequilibrium betw...
Clothier J, Small A, Hinch G, Barwick J, Brown WY.Chronic musculoskeletal pathologies are common in horses, however, identifying related effects can be challenging. This study tested the hypothesis that movement sensors and analgesics could be used in combination to confirm the presence of restrictive pathologies by assessing lying time. Four horses presenting a range of angular limb deformities (ALDs) and four nonaffected controls were used. The study comprised two trials at separate paddock locations. Trial A consisted of a 3-day baseline phase and 2 × 3-day treatment phases, during which two analgesics were administered to two ALD horses...
Liefman CE.Successful active immunisation of horses against tetanus is dependent on a number of factors of which the toxoid preparation used, its method of application and the ability of the individual horse to respond are fundamental. Two immunisation schedules using an aluminium-based toxoid preparation were examined and the protection determined by monitoring the level of antitoxin afforded by each schedule. The results obtained demonstrated that 2 doses of this toxoid are necessary to ensure 12 months protection in all horses. These results are discussed in relation to the factors involved in active ...
Pietrani M, Losinno L, Cuervo Arango J.In the present study, 2.228 cycles of 180 Polo Argentino donor mares from an embryo transfer program in Argentina were examined to evaluate the effects of: (1) Interval from Prostaglandin F2alpha analog treatment to ovulation (ITO) on embryo recovery rate (ERR); (2) ITO on number of embryos per flushing (EPF); (3) ITO on multiple ovulation (MO) rate; (4) ITO from donor mare on pregnancy rate (PR) in recipient mares. Mares were inseminated with fresh semen from 31 fertile stallions in the induced estrus. Embryo flushing was performed 7-8 days postovulation. Following embryo flushing, donor mar...