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.
Pumarola M, Vidal E, Trens JM, Serafín A, Marquez M, Ferrer I.Neuronal intranuclear inclusion disease (NIID) is reported in a 16-year-old Pure Spanish breed female horse suffering from progressive ataxia and motor deficiencies. The neuropathological study revealed NIIs throughout the central nervous system, although mainly in the brain stem and spinal cord. This distribution did not correlate with neuron loss, which was marked in the hippocampus and moderate in the neocortex, particularly in the occipital cortex. As in humans, NIIs in the horse were hyaline autofluorescent inclusions composed of non-membrane-bound aggregates of filaments and fine granule...
Loomis PR, Squires EL.Success with frozen semen requires attention to detail and a basic understanding of the techniques for properly handling and thawing and inseminating frozen semen. Practitioners should also be familiar with strategies used for managing mares for insemination with thawed semen. This manuscript will review those techniques and also present fertility data collected in a commercial setting. Factors that affect pregnancy rates for mares inseminated with frozen-thawed semen such as timing and frequency of insemination were examined for two separate data sets consisting of 332 and 536 mare cycles col...
Pfau T, Witte TH, Wilson AM.Biomechanical studies often employ optical motion capture systems for the determination of the position of an object in a room-based coordinate system. This is not ideal for many types of study in locomotion since only a few strides may be collected per ;trial', and outdoor experiments are difficult with some systems. Here, we report and evaluate a novel approach that enables the user to determine linear displacements of a proprietary orientation sensor during cyclical movement. This makes experiments outside the constraints of the laboratory possible, for example to measure mechanical energy ...
Payne RC, Hutchinson JR, Robilliard JJ, Smith NC, Wilson AM.We provide quantitative anatomical data on the muscle-tendon units of the equine pelvic limb. Specifically, we recorded muscle mass, fascicle length, pennation angle, tendon mass and tendon rest length. Physiological cross sectional area was then determined and maximum isometric force estimated. There was proximal-to-distal reduction in muscle volume and fascicle length. Proximal limb tendons were few and, where present, were relatively short. By contrast, distal limb tendons were numerous and long in comparison to mean muscle fascicle length, increasing potential for elastic energy storage. W...
Gil L, Saura S, Echegaray A, Martinez F, de Blas I, Akourki A, Gonzalez N, Espinosa E, Josa A.The present study evaluated the effect of supplementing the medium used to mature equine oocytes in vitro with oestrous mare serum (EMS) or horse follicular fluid (HFF). To this end, 144 ovaries were obtained from mares aged 16-21 months and transported to the laboratory in Dulbecco's phosphate buffered saline (D-PBS) at 30 degrees C. Oocytes were harvested from the ovaries by slicing, and then selected for in vitro maturation (IVM) according to the number of cumulus cell layers and the characteristics of the cytoplasm. The selected oocytes were washed three times in TCM199 medium plus HEPES (...
Quinlivan M, Zamarin D, García-Sastre A, Cullinane A, Chambers T, Palese P.Equine influenza is a common disease of the horse, causing significant morbidity worldwide. Here we describe the establishment of a plasmid-based reverse genetics system for equine influenza virus. Utilizing this system, we generated three mutant viruses encoding carboxy-terminally truncated NS1 proteins. We have previously shown that a recombinant human influenza virus lacking the NS1 gene (delNS1) could only replicate in interferon (IFN)-incompetent systems, suggesting that the NS1 protein is responsible for IFN antagonist activity. Contrary to previous findings with human influenza virus, w...
Carnevale EM, Coutinho da Silva MA, Panzani D, Stokes JE, Squires EL.Oocyte transfer is a potential method to produce offspring from valuable mares that cannot carry a pregnancy or produce embryos. From 2000 through 2004, 86 mares, 19.2 +/- 0.4 yr of age (mean +/- S.E.M.), were used as oocyte donors in a clinical program at Colorado State University. Oocytes were collected from 77% (548/710) of preovulatory follicles and during 96% (548/570) of cycles. Oocytes were collected 21.0+/-0.1h after administration of hCG to estrous donors and cultured 16.4 +/- 0.2 h prior to transfer into recipients' oviducts. At 16 and 50 d after transfer, pregnancies were detected i...
Nagamine CM, Castro F, Buchanan B, Schumacher J, Craig LE.Spirochetes were identified histologically in canker (proliferative pododermatitis) in 3 horses. The data suggest that spirochetes may contribute to the pathology of equine chronic foot diseases similar to the manner in which they contribute to the pathology of bovine papillomatous digital dermatitis and contagious ovine digital dermatitis.
Lorenzo-Figueras M, Preston T, Ott EA, Merritt AM.To evaluate the effect of ingestion of a high-carbohydrate versus a high-fat meal on relaxation of the proximal portion of the stomach and subsequent gastric emptying in horses. Methods: 6 healthy adult horses. Methods: The study consisted of 2 phases. In phase I, horses were offered a high-fat (8% fat) or a high-carbohydrate (3% fat) pelleted meal (0.5 g/kg) of identical volume, caloric density, and protein content. In phase II, meals consisted of a commercial sweet feed meal (0.5 g/kg) or this meal supplemented with corn oil (12.3% fat) or an isocaloric amount of glucose (2.9% fat). Proximal...
Lopes MS, Mendonça D, Cymbron T, Valera M, da Costa-Ferreira J, Machado Ada C.The analysis of mitochondrial D-loop sequences (408 bp) from 145 Lusitano founder mares yielded a total of 27 different haplotypes. The distribution of these mtDNA sequences was quite unequal, with the three most frequent ones representing 56.5% of all the Lusitano founder mares and 14 haplotypes (51.9%) being rare variants found only once in the sampling. Four main haplotype clusters were present in the Lusitano breed. The comparison of these sequences with other equine haplotypes shows that they fall in groups shared with other horse breeds. These data support the hypothesis of multiple dome...
Riggenbach Ch, Stranzinger G, Poncet PA, Glowatzki ML, Muntwyler J, Gaillard C, Rieder S.In this study it was investigated whether the "Einsiedler" warmblood horse, a historically old horse population from central Switzerland (Abbey of Einsiedeln), is distinguishable from micellaneous horse breeds, using molecular genetic techniques. The breeding history of Einsiedler horses is characterised by systematic line breeding through the dams. Therefore, two Einsiedler dam lines (N = 28), going back to the middle of the 19th century according to pedigree entries, were the focus of the survey. Random samples of diverse warmblood horse populations, but also samples from more distinct types...
Tharasanit T, Colenbrander B, Stout TA.Horse embryos are rarely cryopreserved in practice because expanded blastocysts tolerate freezing poorly, and the embryo begins expanding very soon after entering the uterine cavity. This study examined the effects of freezing on cytoskeleton integrity, and investigated whether cell damage could be reduced using trypsin to thin the blastocyst capsule or cytochalasin-B (cyto-B) to stabilise the cytoskeleton. Sixty-nine embryos were recovered 7 days after ovulation and equilibrated in 10% glycerol, with or without pretreatment with 0.2% trypsin or 7.5 microg/ml cyto-B. Forty-two of the embryos w...
Young LE, Rogers K, Wood JL.Cardiac morphology in human athletes is known to differ, depending on the sports-specific endurance component of their events, whereas anecdotes abound about superlative athletes with large hearts. As the heart determines stroke volume and maximum O(2) uptake in mammals, we undertook a study to test the hypothesis that the morphology of the equine heart would differ between trained horses, depending on race type, and that left ventricular size would be greatest in elite performers. Echocardiography was performed in 482 race-fit Thoroughbreds engaged in either flat (1,000-2,500 m) or jump racin...
Hodgson D, Howe S, Jeffcott L, Reid S, Mellor D, Higgins A.Oral administration of altrenogest for oestrus suppression in competition horses is believed to be widespread in some equestrian disciplines, and can be administered continuously for several months during a competition season. To examine whether altrenogest has any anabolic or other potential performance enhancing properties that may give a horse an unfair advantage, we examined the effect of oral altrenogest (0.044 mg/kg), given daily for a period of eight weeks, on social hierarchy, activity budget, body-mass and body condition score of 12 sedentary mares. It was concluded that prolonged ora...
Almeida J, Ball BA.The objective of this study was to compare the effect of alpha-tocopherol and its ester, alpha tocopherol succinate, on lipid peroxidation and motility of equine spermatozoa. In experiment one, spermatozoa were incubated with dl-alpha-tocopherol (5, 25, 100 or 500 microM), DL-alpha tocopherol succinate (5, 25, 100 or 500 microM) or vehicle (0.5% ethanol) at 38 degrees C, and sperm motility was determined at 30, 60 and 120 min. In experiment two, spermatozoa loaded with the lipophilic probe, C11BODIPY(581/591), were incubated with dl-alpha-tocopherol (50 and 100 microM), DL-alpha-tocopherol suc...
Moore AI, Squires EL, Graham JK.Seminal plasma is generally removed from equine spermatozoa prior to cryopreservation. Two experiments were designed to determine if adding seminal plasma back to spermatozoa, prior to cryopreservation, would benefit the spermatozoa. Experiment 1 determined if different concentrations of seminal plasma affected post-thaw sperm motility, viability and acrosomal integrity of frozen/thawed stallion spermatozoa. Semen was washed through 15% Percoll to remove seminal plasma and spermatozoa resuspended to 350 x 10(6)sperm/mL in a clear Hepes buffered diluent containing either 0, 5, 10, 20, 40 or 80%...
Davies HM, Watson KM.The aims of this study were to test whether longer third metacarpal (MC3) bones had thicker dorsal cortices in a group of racehorses that were exercising at similar maximum speeds, and to establish if horses with larger differences in length between their right and left MC3 bones showed larger differences in the dorsal cortical thickness between the two limbs. Methods: An observational study. Methods: Forty Thoroughbred racehorses aged between 2 and 6 years and in training at racing speed at two racing stables were used. Two sets of radiographs of each left and right metacarpus of each horse w...
Moussa M, Bersinger I, Doligez P, Guignot F, Duchamp G, Vidament M, Mermillod P, Bruyas JF.Vitrification using open pulled straw (OPS) has provided encouraging results with embryos from other species. The aim of this study was to compare the survival of 6.5- and 6.75-day-old equine embryos after OPS vitrification and slow-cooling. Eighteen embryos were frozen using a slow-cooling method. Embryos were placed in modified PBS with increasing glycerol concentration (2.5%, 5%, 7.5% and 10% (v/v) 5 min each). Embryos were loaded into 0.25 ml straws then placed in a programmable freezer and subsequently plunged into liquid nitrogen. After thawing, cryoprotectant was removed by five steps w...
Dabareiner RM, Cohen ND, Carter GK, Nunn S, Moyer W.To determine the types of musculoskeletal problems that result in lameness or poor performance in horses used for team roping and determine whether these problems are different in horses used for heading versus heeling. Methods: Retrospective study. Methods: 118 horses. Methods: Medical records of team roping horses that were evaluated because of lameness or poor performance were reviewed to obtain information regarding signalment, primary use (ie, head horse or heel horse), history, results of physical and lameness examinations, diagnostic tests performed, final diagnosis, and treatment. Resu...
Diaz FA, Gutierrez EJ, Cramer E, Paccamonti DL, Gentry GT, Bondioli KR.Satisfactory pregnancy rates can now be achieved following the cryopreservation of large equine embryos. Nonetheless, its wide application might be limited by the fact that the cryopreservation of large equine embryos requires a specialized micromanipulation equipment and micromanipulation/vitrification skills. Alternatives should be developed to increase its utilization and widespread application in the commercial equine industry. To determine if large equine embryos are able to remain viable during transport from farms to specialized centers for embryo cryopreservation, we evaluated pregnanc...
Stojiljkovic N, Leroux F, Bubanj S, Popot MA, Paris A, Tabet JC, Junot C.There is an urgent need to implement holistic and untargeted doping control protocols with improved discriminatory power, compared to conventional methods that only target doping agents. Metabolomics, which aims to characterize all metabolites present in biological matrices, could fulfill this need. In this context, the aim of this study was to evaluate the impact of environmental factors on the ability to obtain a metabolic signature of stanozolol administration in horse doping situation. Urine samples from 16 horses breeded in two different places were collected over a one-year period, befor...
Vergari C, Pourcelot P, Ravary-Plumioën B, Dupays AG, Jacquet S, Audigié F, Denoix JM, Laugier P, Mitton D, Crevier-Denoix N.Equine superficial digital flexor tendons (SDFT) are often injured, and they represent an excellent model for human sport tendinopathies. While lesions can be precisely diagnosed by clinical evaluation and ultrasonography, a prognosis is often difficult to establish; the knowledge of the injured tendon's mechanical properties would help in anticipating the outcome. The objectives of the present study were to compare the axial speed of sound (SOS) measured in vivo in normal and injured tendons and to investigate their relationship with the tendons' mechanical parameters, in order to assess the ...
Multigner L, Magistrini M, Ducot B, Spira A.Several reports have suggested that human semen quality has declined throughout the world over the last few decades. Chemicals in the environment acting as endocrine disrupters have been implicated as a possible cause. If this is indeed the case, then similar effects may be observed in animals. We analyzed 1489 ejaculates collected from 390 Breton draught stallions between 1981 and 1996. Semen was collected from all the stallions at a single center, according to standardized semen collection protocols and laboratory methods. Semen volume decreased slightly but significantly and there was an in...
Kelley D, LeBlanc MM, Warren LK, Mortensen CJ.Supplementation with L-arginine can increase uterine arterial blood flow and vascular perfusion of the preovulatory follicle in mares. Increased vascular perfusion of the preovulatory follicle has been correlated with successful pregnancy in mares. The objective of this study was to determine if supplemental L-arginine would increase ovarian arterial blood flow, vascular perfusion of the preovulatory follicle, and embryo recovery rates in mares. Mares were blocked by age and breed and assigned at random within block to L-arginine supplementation or control groups. Mares were fed L-arginine beg...
Clauss M, Lang-Deuerling S, Kienzle E, Medici EP, Hummel J.To test whether mineral recommendations for horses are likely to guarantee adequate mineral provision for tapirs (Tapirus spp.), we investigated the apparent absorption (aA) of macro and micro-minerals in 18 tapirs from five zoological institutions in a total of 24 feeding trials with total faecal collection. Samples of feeds and faeces were analysed for Ca, P, Mg, Na, K, Fe, Cu and Zn. The resulting aA coefficients and the linear relationships of apparently absorbable dietary mineral content to total dietary mineral content (per 100 g dry matter) were compared with data for domestic horses. W...
Schaer BD.The emergency clinician is frequently in the position of receiving, evaluating, and initiating treatment on horses with ophthalmic emergencies or orbital trauma. In the best of circumstances, an ophthalmologist is available to guide initial therapy and ultimately assume responsibility for the management of the patient during the remainder of its hospitalization, but this is not always the case. The information presented here is meant to provide the emergency clinician with basic guidelines for the initial assessment and management of horses sustaining ocular injuries or presented with an ophth...
Van de Velde M, Roels K, Ververs C, Gerits I, Govaere J.In recent years, the interest in equine foetal gender determination (FGD) during gestation increased remarkably. Ultrasonographic FGD can be performed in two different periods during gestation. The earliest examination can take place at a gestational age of 60-70 days, whereby the genital tubercle is used to differentiate between male and female foeti. The time window of the second approach is wider (120-210 days), and there are more characteristics to take into consideration. In this article, the feasibility and accuracy of ultrasonographic FGD in mid- to late gestation are evaluated. One h...
Lofgren EA, Rice BMG, Brady CM.Horse welfare is a sensitive topic that often results in a variety of strong feelings when discussed in the horse-owning public. This study used a scenario-based questionnaire in a positive psychology approach to assess the public's feelings and discussions about horse welfare. Results indicated themes in important welfare qualities such as turnout, shelter, and ability to express natural behaviors, as well as a positive discussion about welfare. This study provides future implications for further research techniques in this area as well as communicative strategies surrounding equine welfare p...
Ford EJ, Simmons HA.The production of propionate in the caecum of the horse has been measured in two Shetland-type ponies fitted with caecal and colonic cannulas and fed on hay or on hay and wheat bran. A continuous intracaecal infusion of 14C-labelled sodium propionate was used and samples were obtained from a cannula at the origin of the right ventral colon. A simultaneous intravenous infusion of [2-3H]glucose was used to measure total glucose entry. On a hay diet which provided 177 kJ/kg body-weight per d, mean caecal propionate production was 19.6 (range 17.2-21.2) mg/h per kg body-weight and on a hay and whe...
Lovsin E, Fazarinc G, Pogacnik A, Bavdek SV.A typical body format of Slovenian Lipizzan horse was investigated. The study included 6 foals (5 colts and 1 filly) at the Lipica stud farm. They were measured from birth to twenty-seven months and again at forty-four months of age. Measurements included body length, chest circumference, withers height and body mass. All those measurements were statistically evaluated and compared to some other horse breeds to determine the similarity of the growth dynamics of those horse breeds. It was concluded that the parameters of the head and neck reached their full growth at the age of 27 months and al...
Lee D, May K, Faramarzi B.Laminitis is a common but critical disease that causes severe pain and disability in horses. The etiology and pathogenesis of laminitis remain inconclusive and a multimodal therapeutic approach is generally indicated. Acupuncture has been used as a treatment option; however, the required number of treatments is still controversial due to the lack of objective scientific evidence. Objective: The objective of this study was to determine if the response to a second acupuncture treatment differed from the response to the first acupuncture treatment in horses with chronic laminitis. Methods: Fourte...
Berreta A, Kopper JJ, Alexander TL, Kogan CJ, Burbick CR.Probiotics, by definition, are live micro-organisms and should remain viable when they reach the intended site of action which is typically the cecum and/or colon. In humans, probiotics often need enteric protection to survive transit through the proximal gastrointestinal (GI) tract. Typically, equine probiotics do not advertise enteric protection and to the author's knowledge the viability of equine probiotics after exposure to the proximal GI tract has not been evaluated. The objective of this study was to evaluate the effect of an in vitro simulation of the equine proximal GI tract on probi...
Bartolome JA, Wallace SP, de la Sota RL, Thatcher WW.The objective was to evaluate the effect of equine chorionic gonadotropin (eCG) and hCG post artificial insemination (AI) on fertility of lactating dairy cows. In Experiment 1, cows were either treated with eCG on Day 22 post AI (400 IU; n = 80) or left untreated (n = 84). On Day 29, pregnant cows were either treated with hCG (2500 IU; n = 32) or left untreated (n = 36). Pregnancy and progesterone were evaluated on Days 29 and 45. In Experiment 2, cows (n = 28) were either treated with eCG on Day 22 (n = 13) or left untreated (n = 15) and either treated with hCG on Day 29 (n = 14) or left untr...
Francl AT, Amann RP, Squires EL, Pickett BW.The effects of extender and storage at 20 degrees C on equine spermatozoa were evaluated in two experiments using embryo recovery as the end point. In both experiments, inseminations were every other day, starting on Day 2 or 3 of estrus or after a 35-mm follicle was detected, with 250 x 10(6) progressively motile cells (based on initial evaluation). In Experiment 1, semen from two stallions was used to compare the motility and fertility of spermatozoa maintained in a) heated skim milk extender at 37 degrees C with insemination in <1 h; b) E-Z Mixin extender at 37 degrees C with inseminatio...
Solé M, Valera M, Gómez MD, Cervantes I, Fernández J.Limiting the inbreeding rate (∆F) while maximizing genetic gain for any trait of economic interest is especially important in small populations of local breeds, like the Menorca Horse. In this breed, dressage performance is important for the profitability of the breed and should be accounted in the selection criterion. The aim of this study was to assess if a breeding programme aiming at improved dressage performance is feasible in such a small breed. To perform the analysis, animals that were currently available for breeding (between 3 and 20 years) were used. Selection was based on the es...
Brown KA, Sayasith K, Bouchard N, Lussier JG, Sirois J.The type 1 form of 17beta-hydroxysteroid dehydrogenase (17betaHSD1) was the first isoform to be identified and is capable of converting estrone to 17beta-estradiol. This study was aimed at characterizing the molecular structure of the equine 17betaHSD1 gene and cDNA, as well as its molecular regulation during human chorionic gonadotropin (hCG)-induced follicular luteinization/ovulation in vivo. The equine 17betaHSD1 gene was cloned from an equine genomic library and shown to have a conserved genomic structure composed of six exons. Its cDNA sequence was also identified and coded for a 308 amin...
Pomorska-Zniszczyńska A, Szczepanik M, Kalisz G.Videodermoscopy is a novel, noninvasive technique used to examine the appearance of skin and its adnexa. The aim of this study was to assess specific dermoscopic parameters in Arabian purebred mares in particular areas of the body during the winter season. The study was performed in the winter season. Videodermoscopic evaluations of the hair and skin were performed over seven areas of the body: the forehead, mane, neck, chest, flank, croup, and tail. Twenty-one healthy, non-breeding Arabian mares aged 3 to 21 years were selected for the study. The Video-Dermatoscope Vidix 7 (Medici Medical SRL...
Pagan JD, Harris PA.There is considerable debate among horsemen about how to feed horses before exercise. Should horses be fed or fasted before work and when should hay be fed relative to grain and/or exercise? Three experiments were conducted to evaluate if feeding hay with and without grain affects glycaemic and haematological responses in Thoroughbred (TB) horses at rest and during a simulated competition exercise test (CET) on a high-speed treadmill. In Experiment 1, 6 TB horses were fed hay at 3 different times relative to a grain meal. Time of feeding hay affected glycaemic response, plasma protein and wate...
Yamamoto M, Nakagawa K, Fujiwara K, Shimizu A, Ikeguchi M, Ikeguchi M.Equine β-lactoglobulin (ELG) assumes non-native helices during refolding and in partially folded states. Previously, circular dichroism (CD) combined with site-directed mutagenesis identified helical regions in the acid- and cold-denatured states of ELG. It is also known that a fragment of ELG, CHIBL (residues 88-142), has a structure similar to that of the cold-denatured state. For the study reported herein, the structure of a shorter fragment, CHIBLΔF (residues 97-142), was investigated by CD and nuclear magnetic resonance spectroscopy. The secondary chemical shifts clearly showed that non...
Glatter M, Bochnia M, Goetz F, Gottschalk J, Koeller G, Mielenz N, Hillegeist D, Greef JM, Einspanier A, Zeyner A.This study aimed to investigate the impact of the supplementation of a pre-biotic compound [Jerusalem artichoke meal (JAM)] on the glycaemic and insulinaemic response in healthy, non-obese warm-blooded horses. Six adult mares [mean body weight (bwt) 529 ± 38.7 kg; body condition score 5.1 ± 0.49/9] were used. In two equal meals per day, the horses received crushed oat grains (1 g starch/kg bwt per day) and meadow hay (2 kg/100 kg bwt per day) which together were likely to meet the energy recommendation for light work (GfE, ). Additionally, they received either 0.15 g fructo-oligosac...
Parlevliet JM, Kemp B, Colenbrander B.The semen characteristics and testicular size of 398 3-year-old maiden Dutch Warmblood stallions were studied during February and March. Mean values (+/- SD) of age (1030 +/- 88 days) and testicular size (9.8 +/- 0.9 cm) of the maiden stallions were determined as well as the following semen characteristics (mean of two ejaculates, taken 1 h apart): volume (65 +/- 26 ml), sperm concentration (2.061 +/- 1.685 x 10(8) ml-1), total number of spermatozoa (1.129 +/- 0.71 x 10(10)), percentage of progressively motile spermatozoa (68 +/- 9%), percentage of live spermatozoa with normal morphology (66 +...
Brinsko SP, Van Wagner GS, Graham JK, Squires EL.The aim of the present study was to determine whether there are characteristics of fresh, cooled and frozen-thawed semen samples that can be used to predict the suitability of stallion semen for preservation by cooling or freezing. Each of three ejaculates obtained from 12 stallions was divided into aliquots to be analysed for sperm motility, morphology and membrane integrity as fresh, cooled and frozen-thawed samples. The percentage of morphologically normal spermatozoa was similar in fresh and cooled samples and both were greater than in the frozen samples. There were no strong linear relati...
Čebulj-Kadunc N, Frangež R, Kruljc P.Scientific studies on the physiological responses of young horses to workloads are limited. Therefore, the aim of our study was to determine the basal values of some cardiovascular, thermoregulatory, hematological, and biochemical parameters in 10 purebred Lipizzan fillies aged 4 years in the initial phase of training, and their responses to a graded workload, i.e., by lunging for 15 min in four exercise tests at 2-week intervals. The basal values of the measured parameters were within a range for warm-blooded horses and mostly increased after exercise in all four exercise tests. Resting heart...
Eisersiö M, Byström A, Yngvesson J, Baragli P, Lanata A, Egenvall A.When a rider maintains contact on the reins, rein tension will vary continuously in synchronicity with the horse's gait and stride. This continuous variation makes it difficult to isolate the rein tension variations that represent a rein tension signal, complicating interpretation of rein tension data from the perspective of horse-rider interaction. This study investigated (1) the characteristics of a rein tension signal and (2) horse response to a rein tension signal for backing, comparing pressure applied by a bit (bridle), or by a noseband (halter). Twenty Warmblood horses (10 young, 10 adu...
Gómez MD, Menendez-Buxadera A, Valera M, Molina A.A total of 71 522 records (from 3154 horses) with the times per kilometre (TPK), recorded in Spanish Trotter horses (individual races) from racing performances held from 1991 to 2007, were available for this study. The TPK values for the different age groups (young and adult horses) and different distances (1600-2700 m) were considered as different traits, and a bi character random regression model (RRM) was applied to estimate the (co)variance components throughout the trajectory of age groups and distances. The following effects were considered as fixed: the combination of hippodrome-dat...
Parlevliet JM, Colenbrander B.In the selection procedure to acquire a breeding licence, 3-year-old Dutch Warmblood stallions have to undergo a breeding soundness test It is questioned whether this evaluation is predictive of the stallion's fertility results in the first breeding season. Therefore, semen parameters at the beginning of their first breeding season were evaluated and correlated to nonreturn at first cycle and foaling rate of mares bred by stallions (n = 13). The total number of mares inseminated with chilled semen from those stallions was 1055. Semen parameters were recorded on 2 ejaculates, collected 1 h apar...
Step DL, Cummings JF, de Lahunta A, Valentine BA, Summers BA, Rowland PH, Mohammed HO, Eckerlin RH, Rebhun WC.A 9-year-old Quarter Horse mare was examined because of progressive weight loss, weakness, muscle atrophy and tremors, and behavioral change. Selenium and glutathione peroxidase assays, blood lead analysis, erythrocyte transketolase analysis, pseudorabies and Borrelia burgdorferi serology, electromyography, and CSF analysis were performed. Motor neuron degeneration was diagnosed by microscopic examination of neural tissues. The cause of the disease was not substantiated, but several possibilities were excluded via diagnostic testing. Diagnosis of motor neuron degeneration in horses may be made...
Moslemi S, Dintinger T, Dehennin L, Silberzahn P, Gaillard JL.The ability of human and equine placental microsomes to aromatize 7 alpha-methyl-19-nortestosterone (MNT) was studied. Kinetic analysis indicates that MNT shares the androgen-binding site of human and equine placental microsomal aromatases. Human placental microsomal estrogen synthetase had about a 2.5-fold higher relative affinity for MNT than the equine placental enzyme (KiMNT/Km androstenedione of 32 versus 87). However, MNT was not metabolized by human placental microsomes, whereas it was very actively metabolized by equine placental microsomes. Further studies using purified equine cytoch...
Carvalho Seabra J, Hess T, Martinez do Vale M, Spercoski KM, Brooks R, Dittrich JR.Free choice forage could be the best option regarding horses' welfare but can lead to increased body weight (BW), and waste of hay. Automatic box feeders (BF) and slow feeders (SF) decrease food waste, but it is unknown how these affect the horses' time-budget (TB). This study compared the effects of feeding free choice hay (FC), to a SF and an automated BF on the horses' cortisol circadian rhythm (CCR) and behavior by 24-hours continuous behavioral sampling (CBS). The study was designed as a 3 × 3 Latin square design with 15 polo horses divided into 3 groups, for 15 days on each treatment....
