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.
Omura CM, Drumond B, Rossi JL, Coelho CS, Gioso MA.Cephalometric studies are important to quantify abnormalities of jaw length and positioning. In this study, 4 to 7-month-old Quarter horse foals (n = 51) were examined to determine overjet (horizontal overlap) prevalence and measure the size of the physiological diastemata. Results were analyzed in relation to age, sex, and lineage. Another aim of this study was to develop a simple field technique for measuring incisor malocclusion and physiological diastemata dimensions that could be used to monitor the growth of the rostral components of maxilla, incisive bone, and mandible. The overall prev...
LaVigne EK, Jones AK, Londoño AS, Schauer AS, Patterson DF, Nadeau JA, Reed SA.Success as equine athletes requires proper muscle growth in young horses. Muscle hypertrophy occurs through protein synthesis and the contribution of muscle satellite cells, which can be stimulated or inhibited by cytokines and growth factors present during exercise and growth. The hypotheses of this study were that 1) the LM area in young horses would increase over 1 yr, and 2) specific cytokines and growth factors (IL-1β, IL-6, tumor necrosis factor [TNF]-α, IGF-I, and fibroblast growth factor [FGF]-2) would alter proliferation and differentiation of satellite cells isolated from young hor...
Fowler AL, Hansen TL, Strasinger LA, Harlow BE, Lawrence LM.Inorganic P is often added to growing horse diets because organic P, or phytate-P, is believed to have lower digestibility. If horses can efficiently digest organic P, then the need for inorganic P may be reduced. Much of the P in grain-based concentrates fed to growing horses is in the form of phytate-P. Little is known about the ability of growing horses to degrade phytate-P or whether horse age affects mineral digestion in horses. The objective of this study was to examine the effect of age on P, Ca, and Mg digestibility as well as phytate-P degradation. Four yearling geldings and 4 mature ...
Holcomb KE, Tucker CB, Stull CL.Horses in the United States are commonly managed in outside pens or pastures in small groups. Limited research on shade use by domestic horses housed singly in individual pens has shown benefits and a preference for using available shade. The objective of this study was to examine the amount of shade use and the behavioral and physiological responses of small groups of horses when housed with access to shade (SH) and without access to shade (SUN). Thirty-six horses were randomized into 3 consecutive trials using 3 horses per group and 4 groups per trial. Groups experienced 5 d in each treatmen...
Bartoš L, Bartošová J, Pluháček J.In a previous study, we suggested that the common practice of transporting a mare for mating and then bringing her back to an environment that also contains males that did not sire the fetus may be a major cause of high percentages of pregnancy disruption in domestic horses. In this study, we tested whether disruption of pregnancies induced by AI occurs as frequently as after mating with a strange stallion away from home and is affected by the same factors in the home social environment. Based on 77 records, the probability of pregnancy disruption after AI depended on the social environment in...
Li JR, Wang W, Shi FX.The effects of equine chorionic gonadotropin (eCG) on follicular development and ovulation in cyclic guinea pigs were investigated by histological and immunohistochemical analyses. Three groups of guinea pigs (n=12) were administrated subcutaneously with saline, 20 or 50 IU of eCG, respectively, on cyclic Day 12 (Day 1=vaginal openings). Ovaries were collected at 4 and 8 d after administration (6 animals per group each time). The eCG administration induced significant and distinct morphological changes in the ovaries, as it promoted the luteinization of granulosa cells, but not follicular deve...
Kader A, Li Y, Dong K, Irwin DM, Zhao Q, He X, Liu J, Pu Y, Gorkhali NA, Liu X, Jiang L, Li X, Guan W, Zhang Y, Wu DD, Ma Y.Body size, one of the most important quantitative traits under evolutionary scrutiny, varies considerably among species and among populations within species. Revealing the genetic basis underlying this variation is very important, particularly in humans where there is a close relationship with diseases and in domestic animals as the selective patterns are associated with improvements in production traits. The Debao pony is a horse breed with small body size that is unique to China; however, it is unknown whether the size-related candidate genes identified in Western breeds also account for the...
Senos R, Ribeiro MS, Martins Kde S, Pereira LV, Mattos MF, Kfoury Júnior JR, Rodrigues MR.Although bodypainting has been reported as a great resource for teaching surface anatomy of humans, its use in veterinary anatomy has not been scientifically reported. In the present study, bodypainting was performed on 4 horses for anatomy teaching purposes of the equine locomotor apparatus. We aimed to use the bodypainting method as an additional tool to classic teaching and to test the relevance of our purpose. Twenty one Brazilian veterinary students were given a 90-min session, which included a presentation of painted horses, with opportunities for the students to ask questions and to pal...
Johnson AK, Hinrichs K.There are few reports on the birth of foals resulting from equine adult somatic cell nuclear transfer (NT). On evaluation of reports of 28 live-born adult somatic-cell NT (clone) foals, 3 died within 2 weeks of birth of complications. Approximately 50 % of all reported cloned foals had complications, some requiring aggressive supportive care. The most common abnormalities reported were neonatal maladjustment syndrome, enlarged umbilical remnant, and angular deformity of the forelimbs, similar to problems described in cloned cattle. In contrast, large offspring syndrome and gross abnormalities ...
Aurich C, Budik S.Early equine pregnancy shares many features with that of more intensively assessed domestic animals species, but there are also characteristic differences. Some of those are poorly understood. Descent of the equine conceptus into the uterine lumen occurs at day 5 to 6 after ovulation but is only possible when the embryo secretes prostaglandin E2. Although maintenance of equine pregnancy probably involves secretion of a conceptus derived anti-luteolytic factor, this agent has not been identified. Rapid growth, conceptus mobility and presence of an acellular capsule at the time of maternal recog...
Costa MC, Stämpfli HR, Allen-Vercoe E, Weese JS.The intestinal microbiota is a complex polymicrobial ecosystem that exerts extremely important roles in the development and maintenance of health. Recently, as new sequencing technologies have become more available, there has been a revolution in the understanding of the equine intestinal microbiota. However, studies characterising the pioneer intestinal bacteria colonising foals and its development over time are still limited. Objective: The objectives of this study were to characterise the intestinal bacterial colonisation of newborn foals and to follow individual animals over time until age...
Firshman AM, Borgia LA, Valberg SJ.To compare effects of training on conventional and underwater treadmills on fiber properties and metabolic responses of the superficial digital flexor (SDF) and gluteal muscles to high-speed exercise in horses. Methods: 6 unconditioned Quarter Horse-type horses. Methods: 6 horses were walked on underwater and conventional treadmills for 5 d/wk (maximum, 40 min/d) for 8 weeks in a randomized crossover design (60-day detraining period). Horses underwent a standardized exercise test (SET) at high speed before and after training. Analyte concentrations and fiber characteristics were measured in mu...
Waldern NM, Wiestner T, Ramseier LC, Weishaupt MA.To compare gait mechanics and limb loading in Icelandic horses tölting and trotting at equal speeds and estimate their impact on orthopedic health. Methods: 12 orthopedically normal Icelandic horses. PROCEDURES Kinetic and kinematic gait variables were simultaneously recorded as each horse was ridden at a tölt and trot on an instrumented treadmill at 3.4 m/s and 3.9 m/s. Differences between gaits were tested via 1-factor repeated-measures ANOVA. Results: Horses had a higher stride rate and lower stride impulses at a tölt than at a trot. For forelimbs at a tölt, shorter relative stance dura...
Liu SH, Hu DF, Li K.Oviposition site selection is an important aspect of the behavioural ecology of insects. A comparison of the habitats used by a species enhances our understanding of their adaptation to altered environments. We collected data on the oviposition behaviours of Gasterophilus pecorum (Diptera: Gasterophilidae) in its habitat in Kalamaili Nature Reserve (KNR), Xinjiang, China between March and October 2014. We found 91 quadrats were used by G. pecorum for oviposition. Examining 13 ecological factors using the t-test, chi-square test, and principal component analysis showed that G. pecorum's oviposi...
Andrieu J, Henry S, Hausberger M, Thierry B.In species that move in cohesive groups, animals generally reach decisions through socially distributed processes, and individual knowledge is expected to influence collective decision making. Pooling of information should not be considered a general rule, however, since conflicts of interest may occur between group members. When resources are limited or highly attractive, higher-ranking individuals can prevent others from accessing food, and subordinates may have an interest in withholding information about its location. We investigated the role individual knowledge may play in recruitment pr...
Aguiar FL, Lunardi FO, Lima LF, Rocha RM, Bruno JB, Magalhães-Padilha DM, Cibin FW, Nunes-Pinheiro DC, Gastal MO, Rodrigues AP, Apgar GA, Gastal EL....This study investigated the effect of adding different concentrations of bovine recombinant follicle-stimulating hormone on the IVC of equine preantral follicles enclosed in ovarian tissue fragments. Randomized ovarian fragments were fixed immediately (fresh noncultured control) or cultured for 1 or 7 days in α-MEM(+) supplemented with 0, 10, 50, and 100 ng/mL FSH and subsequently analyzed by classical histology. Culture media collected on Day 1 or Day 7 and were analyzed for steroids (estradiol and progesterone) and reactive oxygen species (ROS). After Day 1 and Day 7 of culture, 50-ng/mL FS...
Levine DG.The first weeks of life are critical in many aspects, and the musculoskeletal system is no exception. Being able to stand and nurse within hours of life is necessary for survival. Laxity, flexural deformities, and skeletal immaturity can all make it difficult for neonates to ambulate. The increased vascularity to bones and cartilage mixed with the newly forming immune system also make neonates susceptible to infections that we rarely see in adult animals. This article concentrates on orthopedic conditions seen in the first 2 weeks of life.
Wilkins PA.Equine neonatal intensive care units have expanded knowledge and understanding of the normal and abnormal physiology of the equine neonate, resulting in successful treatment of critically ill equine neonates. The overall survival rate has increased tremendously since the early 1980s, from a little more than 50% to 80% or more for most facilities. The severely septic foal and the very premature foal still remain large treatment challenges, but less severely septic foals and foals challenged by adverse peripartum events such as dystocia and placentitis are surviving to hospital discharge and per...
Tennent-Brown BS, Morrice AV, Reed S.Neonatal encephalopathy is the most common neurologic condition affecting newborn foals and shares similarities with perinatal asphyxia syndrome of human infants. In many cases of neonatal encephalopathy there is no obvious episode of acute or chronic hypoxia and other mechanisms likely play a role in the pathogenesis. Increased concentrations of neuroactive progestagens are found in affected foals; whether these molecules are protective, as has been suggested, or play a role in the pathogenesis is unknown. Neurologic diseases other than neonatal encephalopathy affect foals occasionally and sh...
Teixeira FA, Araújo AL, Ramalho LO, Adamkosky MS, Lacerda TF, Coelho CS.The aim of this study was to evaluate the effects of oral creatine supplementation on the athletic performance of equines used for barrel racing. Ten healthy Quarter Horses, or Quarter Horse crossbred, weighing 429.7 ± 25.3 kg and with mean age of 3.8 ± 1.2 years, were used. Animals were evaluated in four different moments (M1, M2, M3, M4), and between M3 and M4, they were supplemented with 28 g of creatine/100 kg of body weight, orally, for 45 days. Although significant alterations for LDH activity, plasma glucose and packed cell volume were observed, it was possible to conclude th...
Tomonaga M, Kumazaki K, Camus F, Nicod S, Pereira C, Matsuzawa T.Mammals have adapted to a variety of natural environments from underwater to aerial and these different adaptations have affected their specific perceptive and cognitive abilities. This study used a computer-controlled touchscreen system to examine the visual discrimination abilities of horses, particularly regarding size and shape, and compared the results with those from chimpanzee, human and dolphin studies. Horses were able to discriminate a difference of 14% in circle size but showed worse discrimination thresholds than chimpanzees and humans; these differences cannot be explained by visu...
Guthrie AJ, Coetzee P, Martin DP, Lourens CW, Venter EH, Weyer CT, Joone C, le Grange M, Harper CK, Howell PG, MacLachlan NJ.This is a report of the complete genome sequences of plaque-selected isolates of each of the four virus strains included in a South African commercial tetravalent African horse sickness attenuated live virus vaccine.
Staszyk C.The routine inspection of the equine oral cavity allows a numerical assessment of the teeth and provides information about positional changes within the dentition. By use of appropriate dental equipment, the occlusal surfaces of all teeth can be inspected and diagnosed. However, neither the teeth nor their occlusal surfaces are constant structures. Instead, equine teeth and, in particular, their occlusal surfaces are subjected to continuous morphological and positional changes due to the effects of aging and the equine-specific high amount of occlusal wear. Therefore, it is mandatory to define...
Baker T, Carpenter S, Gubbins S, Newton R, Lo Iacono G, Wood J, Harrup LE.Biting midges of the genus Culicoides Latreille, 1809 (Diptera: Ceratopogonidae) cause a significant biting nuisance to equines and are responsible for the biological transmission of African horse sickness virus (AHSV). While currently restricted in distribution to sub-Saharan Africa, AHSV has a history of emergence into southern Europe and causes one of the most lethal diseases of horses and other species of Equidae. In the event of an outbreak of AHSV, the use of insecticide treated nets (ITNs) to screen equine accomodation is recommended by competent authorities including the Office Interna...
Burger D, Dolivo G, Wedekind C.Sperm competition theory predicts semen characteristics to be affected by the social environment. We used the polygamous horse (Equus caballus) to experimentally study within-subject plasticity in response to different social environments. Stallions were sequentially exposed, over a period of 8 weeks each, to other stallions and then singly to mares, or vice versa (in adjacent boxes separated by grills). Ejaculates were collected to determine semen characteristics. Highest sperm numbers were found in stallions that were first exposed to other stallions and then to mares, while lowest sperm num...
Brink P, Schumacher J.To describe canaliculosinostomy performed to resolve epiphora caused by nasolacrimal duct obstruction and to report the outcome of horses undergoing this procedure. Methods: Case series. Methods: Seven horses with uni- or bilateral nasolacrimal duct obstruction. Methods: The ventral lacrimal punctum and canaliculus were expanded with catheters of increasing diameter until a 14 gauge, Jamshedi needle could be passed into and through the lacrimal sac into the caudal maxillary sinus. One end of a plastic tube was inserted through the needle into the sinus, and the needle was withdrawn over the tu...
Marycz K, Kornicka K, Basinska K, Czyrek A.Currently, equine metabolic syndrome (EMS), an endocrine disease linked to insulin resistance, affects an increasing number of horses. However, little is known about the effect of EMS on mesenchymal stem cells that reside in adipose tissue (ASC). Thus it is crucial to evaluate the viability and growth kinetics of these cells, particularly in terms of their application in regenerative medicine. In this study, we investigated the proliferative capacity, morphological features, and accumulation of oxidative stress factors in mesenchymal stem cells isolated from healthy animals (ASCN) and horses s...
Balao da Silva CM, Ortega-Ferrusola C, Morrell JM, Rodriguez Martínez H, Peña FJ.To date, the only repeatable method to select spermatozoa for chromosomal sex is the Beltsville sorting technology using flow cytometry. Improvement of this technology in the equine species requires increasing awareness of the modifications that the sorting procedure induces on sperm intactness. Oxidative stress is regarded as the major damaging phenomenon, and increasing evidence regards handling of spermatozoa - including sex sorting - as basic ground for oxidative damage. The aim of this study was to disclose whether the flow cytometric sorting procedure increases the production of reactive...
Thamm DH, Ehrhart EJ, Charles JB, Elce YA.The enzyme cyclooxygenase-2 (COX-2) is expressed in some tumor and stromal tissues, and catalyzes production of prostaglandins with growth stimulatory, antiapoptotic, proangiogenic, and immunosuppressive properties. Pharmacologic inhibition of COX-2 is associated with antitumor activity in various human and canine malignancies. The purpose of this study was to assess COX-2 expression in a series of equine sarcoids, melanomas, and squamous-cell carcinomas (SCC). COX-2 expression was assessed in formalin-fixed paraffin-embedded tissues from 14 sarcoids, 11 melanomas, and 37 SCC that represent va...
Meyers-Brown GA, McCue PM, Troedsson MH, Klein C, Zent W, Ferris RA, Lindholm AR, Scofield DB, Claes AN, Morganti M, Colgin MA, Wetzel RL, Peters AR....Traditionally, mares are put under artificial lights to advance the first ovulation of the year. The aim of the present study was to determine the efficacy of recombinant equine FSH (reFSH) in stimulating follicular development and advancing the first ovulation of the year in seasonally anestrous mares compared with anestrous mares given a placebo. Both groups of mares were housed under ambient light conditions. Sixty deep anestrous mares of light horse breeds (follicular diameters ≤ 20 mm in diameter and progesterone <1 ng/mL) were maintained under a natural photoperiod at three differen...
Lagos J, Tadich TA.Hematological and biochemical reference intervals are an important tool for health assessment and treatment decision-making in veterinary medicine. Lack of information about reference intervals (RI) in mules force professionals to apply reference intervals developed for horses or donkeys, with the risk of misinterpretation. Thus, the aim of this study was to determine hematological and biochemical RI for healthy mules and compare them with those proposed in literature for horses, donkeys and mules. A total of 142 healthy mules (mixed breed mares × Baudet du Poitou) of both sex, all between 7 ...
Timoney PJ, McCollum WH, Roberts AW, McDonald MJ.Clinical cases of equine arteritis virus infection have not been diagnosed in Kentucky since 1984, and there has been no indication that any of the horses involved in the 1984 epizootic have since been responsible for spread of the disease to horses in other states or other countries. Cases of abortion caused by naturally acquired infection with this virus have not been confirmed in 1984 or 1985. Neither field nor vaccine strains of equine arteritis virus have been shown to induce teratologic abnormalities or the carrier state in foals born to infected or vaccinated mares. The carrier stallion...
Kuhnke S, Bär K, Bosch P, Rensing M, Borstel UKV.The study compared results of the traditional horse judging system (T) using subjective grades with those of a novel system of linear scoring (LS) using an application ("Breed Show App"). The horse's quality in relation to the total breeding aim was evaluated based on weighting factors for 57 individual traits commonly regarded in T, thus allowing immediate ranking of the horses. Results were stated as total grade in percent for both systems. One thousand nine hundred nine American Quarter horses were judged at regular breed shows with either T (n = 883), LS (n = 1,026), or both systems (n ...
Schumacher SA, Yardley J, Bertone AL.Magnesium sulfate (MgSO ) was administered to calm competition horses. We evaluated the impact of regulatory requirements for the handling of blood samples on plasma ionized magnesium (iMg), ionized calcium (iCa), the iMg to iCa ratio, and pH. We hypothesized that iCa, iMg. and iMg/iCa would be similar among storage and collection methods. Four blood samples were collected from each of 50 horses on the same day: Group 1 - collection in a heparinized syringe and processed within hours in a clinical laboratory; Group 2 - collection into a plasma separator tube (PST) centrifuged just prior to ana...
Ellegren H, Andersson L, Johansson M, Sandberg K.A synthetic polynucleotide (TG)n was hybridized to equine DNA digested with HinfI and hypervariable hybridization patterns were obtained. Mendelian inheritance of these DNA fingerprinting patterns was confirmed by pedigree analysis. Estimates of the probabilities of identical band patterns in unrelated individuals of different breeds (Swedish Trotters, North Swedish Trotters, Thoroughbreds and Arabians) were in the range 1 x 10(-4) - 7 x 10(-6). The variability derived with the (TG)n probe in horses was higher than what we obtained with several other commonly used probes for DNA fingerprinting...
Hanggi EB, Ingersoll JF, Waggoner TL.In the past, equine color vision was tested with stimuli composed either of painted cards or photographic slides or through physiological testing using electroretinogram flicker photometry. Some studies produced similar results, but others did not, demonstrating that there was not yet a definitive answer regarding color vision in horses (Equus caballus). In this study, a pseudoisochromatic plate test--which is highly effective in testing color vision both in small children and in adult humans--was used for the first time on a nonhuman animal. Stimuli consisted of different colored dotted circl...
Díaz S, Giovambattista G, Dulout FN, Peral-García P.Genetic variation in the equine leucocyte antigen-DRB (ELA-DRB) second exon was investigated using polymerase chain reaction (PCR) amplification, restriction fragment length polymorphism (RFLP) of PCR products (PCR-RFLP) and deoxyribonucleic acid (DNA) sequencing. Eight distinct PCR-RFLP patterns could be identified in the studied Argentine Creole (AC) horses. The number of observed patterns per individual ranged from four to six, thus confirming the presence of multiple DRB copies in AC horses. Three PCR-RFLP alleles and three new sequences were identified. The estimated rates of synonymous a...
Zabek T, Nogaj A, Radko A, Nogaj J, Słota E.Genetic variation of endangered Biłgoraj horses and two common Polish horse breeds was compared with the use of 12 microsatellite loci (AHT4, AHT5, ASB2, HMS2, HMS3, HMS6, HMS7, HTG4, HTG6, HTG7, HTG10, VHL20). Lower allelic diversity was detected in all investigated populations in comparison to other studies. Large differences in the frequencies of microsatellite alleles between Biłgoraj horses and two other horse breeds were discovered. In all polymorphic loci all investigated breeds were in the Hardy-Weinberg equilibrium. Mean Fis values and the results of a test for the presence of a rec...
Barros IN, Silva SO, Nogueira Neto FS, Asano KM, Souza SP, Richtzenhain LJ, Brandao PE.Gastroenteritis is one of the leading causes of morbidity and mortality among young and newborn animals and is often caused by multiple intestinal infections, with rotavirus and bovine coronavirus (BCoV) being the main viral causes in cattle. Given that BCoV is better studied than equine coronaviruses and given the possibility of interspecies transmission of these viruses, this research was designed to compare the partial sequences of the spike glycoprotein (S), hemagglutinin-esterase protein (HE), and nucleoprotein (N) genes from coronaviruses from adult cattle with winter dysentery, calves w...
Stout TA.During the past 15 years, embryo transfer (ET) has become increasingly widespread within the sport-horse breeding industry. At present, however, the vast majority (>95%) of horse embryos are transferred fresh or after chilled storage for up to 24 h, whereas cryopreservation is rarely employed despite its obvious potential for simplifying recipient mare management and facilitating long-term storage and international transport of embryos. A number of inter-related factors have contributed to the slow development and implementation of equine embryo cryopreservation, and these include the followin...
Pollitt CC, van Eps AW.The recommended duration of cryotherapy in horses is currently extrapolated from human medicine. Prolonged, continuous cryotherapy (days rather than minutes) may be of therapeutic value if it is safe and well tolerated. Objective: To evaluate the effect of prolonged, continuous application of ice and water to the equine distal limb. Methods: A slurry of ice and water was applied to the right forelimb of 4 Standardbred horses for 48 h. Hoof temperature, ambient temperature and ice boot temperature were logged continuously and clinical observations recorded every 2 h. Lameness examinations were ...
McCutcheon LJ, Geor RJ, Ecker GL, Lindinger MI.This study examined sweating responses in six exercise-trained horses during 21 consecutive days (4 h/day) of exposure to, and daily exercise in, hot humid conditions (32-34 degrees C, 80-85% relative humidity). On days 0, 3, 7, 14, and 21, horses completed a standardized exercise test on a treadmill (6 degrees incline) at a speed eliciting 50% of maximal O(2) uptake until a pulmonary artery temperature of 41.5 degrees C was attained. Sweat was collected at rest, every 5 min during exercise, and during 1 h of standing recovery for measurement of ion composition (Na(+), K(+), and Cl(-)) and swe...
Albrizio M, Guaricci AC, Maritato F, Sciorsci RL, Mari G, Calamita G, Lacalandra GM, Aiudi GG, Minoia R, Dell'Aquila ME, Minoia P.The development of fertilizing ability in sperm cells is associated with changes in the plasma membrane. However, to date the exact nature of sequentially activated primary receptors and channels and the signal transduction pathways derived from these remains elusive. We analyzed the expression and localization of the mu-opioid receptor in equine spermatozoa. A transcript corresponding to the third extracellular loop that selectively binds mu agonists was amplified, sequenced and compared with the known sequences in humans, rats and cattle. The amplification product showed a high degree of nuc...
Christensen JW.Fear reactions in horses are a major cause of horse-human accidents, and identification of effective pathways for reduction in fearfulness can help decreasing the frequency of accidents. For a young mammal, the mother is one of the most salient aspects of its environment, and she can have a strong influence on her offspring's behaviour. This study investigated whether fearfulness in foals can be reduced through weekly exposure to usually frightening objects with a habituated mother during the first 8 weeks of life. Prior to foaling, mares (N = 22) were habituated to five initially fear-elic...
Malekipour F, Whitton CR, Lee PV.Subchondral bone injury due to high magnitude and repetition of compressive loading is common in humans and athletic animals such as Thoroughbred racehorses. Repeated loading of the joint surface may alter the subchondral bone microstructure and initiate microdamage in the bone adjacent to the articular cartilage. Understanding the relationship between microdamage, microstructure and mechanical properties of the subchondral bone adjacent to the articular cartilage is, therefore, essential in understanding the mechanism of subchondral bone injury. In this study, we used high-resolution µCT sca...
Hood DM, Wagner IP, Brumbaugh GW.To evaluate the use of hoof wall surface temperature (HWST) as an indirect indicator of digital perfusion and to describe HWST patterns during the prodromal and acute phases of carbohydrate-induced laminitis in horses. Methods: 30 adult horses without foot abnormalities. Methods: Three experiments were performed. In the first, HWST was measured in 2 groups of horses acclimatized to hot (n = 6), or cold (6) environments and exposed to cold (15 C) ambient temperature. In the second experiment, HWST were measured in both forefeet of 6 horses before and after application of a tourniquet to 1 foref...
Soffler C, Hermanson JW.We studied the forelimb interosseus muscle in horses, Equus caballus, to determine the muscular properties inherent in its function. Some authors have speculated that the equine interosseus contains muscle fibers at birth only to undergo loss of these fibers through postnatal ontogeny. We describe the muscle fibers in eight interosseus specimens from adult horses. These fibers were studied histochemically using myosin ATPase studies and immunocytochemically using several antibodies directed against type I and type II myosin heavy chain antibodies. We determined that 95% of the fibers were type...
Huang H, Lavoie-Lamoureux A, Lavoie JP.The endothelium plays a critical role in regulating leukocyte recruitment and migration during inflammation. Recent studies provide evidence that acetylcholine (ACh) and other cholinergic mediators block endothelial cells activation and leukocyte recruitment during inflammation. We thus postulated that the non-neuronal cholinergic system might modulate the recruitment of neutrophils during allergic pulmonary inflammation. In the present study, we examined the effects of cholinergic stimulation on the expression of neutrophil chemokines and adhesion molecules by endothelial cells stimulated by ...
White SL, Williamson LH, Maykuth PL, Cole SP, Andrews FM, Geiser DR.The exercise intensity of horses (n = 175) competing in the cross-country phase of 4 combined training events at 5 levels of competition [novice (N), training (T), preliminary (P), intermediate (I) and advanced (A)] was investigated. Environmental conditions varied from cool and humid (mean +/- s.d. temperature and humidity = 12.1 degrees C +/- 0.6 and 88.4% +/- 8.9 RH) to moderately hot and humid (27.8 degrees C +/- 2.1 and 62.5% +/- 7.8 RH). Heart rates (beats/min) were recorded continuously at 5 s intervals with a heart monitor. Mean +/- s.d. heart rates (beats/min) for each level of compet...
Allen WR.The influence of fetal genotype upon gonadotrophin (PMSG) and progestagen production in mares and donkeys during the first half of pregnancy was examined. The production of PMSG was greatly reduced in mares carrying mule conceptuses and greatly increased in donkeys carrying hinny conceptuses. Fetal genotype had no obvious influence upon progestagen production in mares, but donkeys carrying hinny conceptuses showed extremely high peripheral plasma progestagen concentrations when serum PMSG levels were elevated. Fetal genotype profoundly influences the intensity and rate of success of the matern...
Hildebrandt F, Krieter J, Büttner K, Salau J, Czycholl I.Group housing is claimed to possibly provide horses with a species-appropriate movement possibility, and hence, better welfare. Thus, this study analyzed the daily walked distances of 51 horses held in one group in a "HIT Active Stable" (Hinrichs Innovation + Technik) in Northern Germany by using global positioning system (GPS) technology during a 7 ½-month time span. The daily walking distances of the whole group, as well as newcomers, were investigated. The horses traveled an average of 8.43 km/day. Linear mixed models were applied. The observation day had a significant effect on the dail...
Loup B, André F, Avignon J, Lhuaire M, Delcourt V, Barnabé A, Garcia P, Popot MA, Bailly-Chouriberry L.Short half-life doping substances are, quickly eliminated and therefore difficult to control with traditional analytical chemistry methods. Indirect methods targeting biomarkers constitute an alternative to extend detection time frames in doping control analyses. Gene expression analysis (i.e., transcriptomics) has already shown interesting results in both humans and equines for erythropoietin (EPO), growth hormone (GH), and anabolic androgenic steroid (AAS) misuses. In humans, circulating cell-free microRNAs in plasma were described as new potential biomarkers for control of major doping agen...
Fazio F, Casella S, Giannetto C, Caola G, Piccione G.The aim of the present work was to evaluate the influence of exercise on serum homocysteine and oxidative stress in Thoroughbreds during official races. For our study, ten Thoroughbred mares, 5 years old and clinically healthy, were used. The horses were trained to take part in an official 2100 meter race. Reactive oxygen species (dROMs), antioxidant barrier (Oxy-adsorbent), thiol antioxidant barrier (SHp) and homocysteine (sHcy) were investigated. Blood samples, collected from each horse at rest, immediately after the race, and 30 and 180 min after the end of the race, were collected by jugul...
Deichsel K, Palm F, Koblischke P, Budik S, Aurich C.Lipid peroxidation contributes to the damage of the sperm plasma membrane. In different species, dietary supplementation with antioxidants has been shown to improve semen quality. Therefore, we tested effects of dietary supplementation with antioxidants and l-carnitin on semen quality in Shetland pony stallions (n=6). Semen was collected twice a week over a time period of 16 weeks. From weeks 5 to 12, a special diet for stallions containing a variety of antioxidants (STALLION, Pavo Pferdenahrung GmbH, Goch, Germany; tocopherol 300 mg/day; ascorbic acid 300 mg/day; l-carnitin 4000 mg/day; folic...
Karenina K, Giljov A, Malashichev Y.The manifestation of behavioural lateralization has been shown to be modified by environmental conditions, life experiences, and selective breeding. This study tests whether the lateralization recently found in feral domestic horse (Equus caballus) is evident in undomesticated horses. Mother-offspring interactions were investigated in Przewalski's horse (E. ferus przewalskii) living in their natural habitat in Mongolia. Lateral position preferences during mare-foal spontaneous reunions were used as a behavioural marker of visual lateralization. Preferences were separately assessed for foals' a...
Oliveira CA, Azevedo JF, Martins JA, Barreto MP, Silva VP, Julliand V, Almeida FQ.This study was performed to evaluate the impact of dietary protein levels on nutrient digestibility and water and nitrogen balances in conditioning eventing horses. Twenty-four Brazilian Sport Horses, male and female (8.0 to 15.0 yr; 488 ± 32 kg BW), were used in a randomized design with 4 levels of CP diets: 7.5%, 9.0%, 11.0%, and 13.0%. A digestion assay was performed with partial feces collection over 4 d, followed by 1 d of total urine collection. Data were submitted to regression analysis and adjusted to linear and quadratic models (P < 0.05). No differences were observed in the intake o...
Canisso IF, Carvalho GR, Morel MC, Guimarães JD, McDonnell SM.The objectives were to (i) characterize sexual behavior of donkey stallions (jacks; Equus asinus) during on-farm semen collection using estrous horse mares (mares; Equus caballus); (ii) compare behavior of young (less experienced) versus older (more experienced) jacks; (iii) determine whether semen suitable for artificial insemination (AI) could be collected using mares; and (iv) determine the suitability of using mares in field collection of semen from jacks. Six Pêga jacks (3.5 to 16 yr old), previously conditioned to breed mares, were used. Mount mares were confirmed in estrus by a teaser ...
Secombe CJ, Bailey SR, de Laat MA, Hughes KJ, Stewart AJ, Sonis JM, Tan R.The purpose of this article is to provide a review of the current knowledge and opinions about the epidemiology, clinical findings (including sequelae), diagnosis, treatment and monitoring of equine pituitary pars intermedia dysfunction, particularly in the Australian context. This information and the recommendations provided will assist practitioners in making informed decisions regarding the diagnosis and management of this disorder.
