Equine biomechanics involves the study of the mechanical principles that govern the movement and structure of horses. This field examines the anatomical and physiological aspects that contribute to locomotion, including gait patterns, joint function, and muscle dynamics. Researchers utilize advanced technologies such as motion capture and force plate analysis to assess the efficiency and performance of equine movement. Understanding biomechanics aids in optimizing training regimens, improving performance, and preventing injuries. This page compiles peer-reviewed research studies and scholarly articles that explore the mechanics of equine movement, its applications in sports and rehabilitation, and its impact on overall equine health.
Acri G, Testagrossa B, Piccione G, Arfuso F, Giudice E, Giannetto C.The evaluation of the performance levels in athletic horses is of major importance to prevent sports injuries. Raman spectroscopy is an innovative technique that allows for a rapid evaluation of biomolecules in biological fluids. It also permits qualitative and quantitative sample analyses, which lead to the simultaneous determination of the components of the examined biological fluids. On the basis of this, the Raman spectroscopy technique was applied on serum samples collected from five Italian Saddle horses subjected to a standardized obstacle course preceded by a warm-up to evaluate the ap...
Wang XF, Zhang X, Ma W, Li J, Wang X.Equine infectious anemia virus (EIAV) is a member of the lentivirus genus in the Retroviridae family and is considered an animal model for HIV/AIDS research. An attenuated EIAV vaccine, which was successfully developed in the 1970s by classical serial passage techniques, is the first and only lentivirus vaccine that has been widely used to date. Restriction factors are cellular proteins that provide an early line of defense against viral replication and spread by interfering with various critical steps in the viral replication cycle. However, viruses have evolved specific mechanisms to overcom...
McFadden A, Martin K, Foster G, Vierra M, Lundquist EW, Everts RE, Martin E, Volz E, McLoone K, Brooks SA, Lafayette C.Mutations causing depigmentation are relatively common in Equus caballus (horse). Over 40 alleles in multiple genes are associated with increased white spotting (as of February 2023). The splashed white phenotype, a coat spotting pattern described as appearing like the horse has been splashed with white paint, was previously associated with variants in the PAX3 and MITF genes. Both genes encode transcription factors known to control melanocyte migration and pigmentation. We report two novel mutations, a stop-gain mutation in PAX3 (XM_005610643.3:c.927C>T, ECA6:11,196,181, EquCab3.0) and a m...
Machmoum M, Badaoui B, Petit D, Germot A, El Alaoui MA, Boujenane I, Piro M.Genetic diversity and phylogenetic relationships within the Arabian show horse populations are of particular interest to breeders worldwide. Using the complete mitochondrial DNA D-loop sequence (916 pb), this study aimed (i) to understand the genetic relationship between three populations, the Desert-Bred (DB), a subset of the Kingdom of Saudi Arabia (KSA), United Arab Emirates (UAE) and Bahrain (BAH), the Straight Egyptian (EG) and the Polish bloodline (PL), and (ii) to assess the accuracy of the traditional strain classification system based on maternal lines, as stated by the Bedouin cultur...
Faria R, Vicente A, Silva J.The aim of this study was to evaluate the sprint racing performance of Quarter Horses in Brazil. Estimating genetic parameters, trends and correlations were obtained by single- and two-trait analyses using Bayesian inference (earnings to 2 years of equestrian age, best time and time class at distances of 301 m and 402 m). The data comprised a period of 38 equestrian years (1978 to 2015) with 23,482 sprint race records from 5861 animals. The heritability estimates were of low to moderate magnitude, ranging from 0.10 to 0.37 (single-trait) and from 0.15 to 0.41 (two-traits), and the repeatabilit...
Carmo LG, Werner LC, Michelotto PV, Daros RR.Food rewards are believed to have a positive valence in horses. The aim of this study was to assess the effect of food rewards on horse behavior before entering a horse chute, and behavior and facial movements while restrained in it. Thirteen female adult horses were brought once daily to an animal handling facility for three weeks. In week 1, baseline period, no reinforcement was applied. In weeks 2 and 3, experimental phase, half of the horses received positive reinforcement treatment after entering and remaining in the chute; the remaining horses were considered as controls (no positive rei...
Santos WB, Pereira CB, Maiorano AM, Arce CDS, Baldassini WA, Pereira GL, Chardulo LAL, Neto ORM, Oliveira HN, Curi RA.With the advent of genomics, significant progress has been made in the genetic improvement of livestock species, particularly through increased accuracy in predicting breeding values for selecting superior animals and the possibility of performing a high-resolution genetic scan throughout the genome of an individual. The main objectives of this study were to estimate the individual genomic inbreeding coefficient based on runs of homozygosity (F ), to identify and characterize runs of homozygosity and heterozygosity (ROH and ROHet, respectively; length and distribution) throughout the genome, a...
White-Springer SH, Bruemmer J, Coleman RJ.A core group of 27 equine nutritionists and physiologists joined together in the late 1960s to formally address and enhance the direction of equine research, creating the Equine Nutrition and Physiology Society. In 2003, that growing society transformed into the Equine Science Society, which now serves as the preeminent, internationally recognized scientific equine organization. In recent years, it has been appreciated that equine science encompasses a wide range of focus areas, including exercise science, nutrition, genetics, reproductive physiology, teaching and extension, production and man...
McGowan CM, Ireland JL.Equine endocrine disease is an important area for equine research, requiring an appropriate case definition for inclusion and criteria for exclusion from disease. Defining a case for research may be different from criteria for clinical diagnosis. Further, clinical diagnosis recommendations have been changing regularly, making this area challenging for equine scientists. This review discusses the diagnosis of major equine endocrine diseases, pituitary pars intermedia dysfunction, equine metabolic syndrome and insulin dysregulation, focusing on the most appropriate diagnostic methods for researc...
Bhardwaj A, Nayan V, Legha RA, Bhattacharya TK, Pal Y, Giri SK.Equines' ability in racing and riding as well as gaitedness have influenced the human civilization. Aim of this study was to identify and characterize the novel polymorphisms or SNPs in gene in Indian horse and donkey breeds. In this study, the gene was sequenced and characterized in 72 Indian horses' and 33 Indian donkeys' samples. One SNP (A > C) at 878 was found in studied horses while identical SNPs (A > C) at two different nucleotide positions i.e., 878 and 942 in gene (chromosome 23) were observed in studied Indian donkey breeds. Horses and donkeys both have a non-synony...
Kuckova S, Smirnova TA, Straka D, Meledina A, Santrucek J, Humpolakova K, Hoskova M, Cejnar P, Hynek R.The aim of this work is to offer an alternative or complementary analytical tool to the time-consuming and expensive methods commonly used for the recognition of animal species according to their hair. The paper introduces a simple and fast way for species differentiation of animal hairs called in-sample digestion. A total of 10 European animal species, including cat, cow, common degu, dog, fallow deer, goat, horse, sika deer, rabbit, roe deer, and 17 different breeds of dogs were examined using specific tryptic cleavage directly in hair followed by matrix-assisted laser desorption/ionization-...
Logan AA, Snyder AJ, Nielsen BD.The effects of gait and diameter have been studied independently, but rarely together in equine circular exercise studies. This study aimed to determine the impact of diameter (10-m or 15-m) at various gaits (walk, trot, and canter) on stride frequency or forelimb stance duration. Nine mature horses were outfitted with Tekscan™ Hoof Sensors on their forelimbs during circular and straight-line exercise at various gaits on a clay and sand arena surface. Statistical analysis was performed in SAS 9.4 with fixed effects of exercise type, recording, leg, and breed (PROC GLIMMIX, p < 0.05 significa...
Liehrmann O, Cosnard C, Riihonen V, Viitanen A, Alander E, Jardat P, Koski SE, Lummaa V, Lansade L.Cues such as the human pointing gesture, gaze or proximity to an object are widely used in behavioural studies to evaluate animals' abilities to follow human-given cues. Many domestic mammals, such as horses, can follow human cues; however, factors influencing their responses are still unclear. We assessed the performance of 57 horses at a two-way choice task testing their ability to follow cues of either a familiar (N = 28) or an unfamiliar informant (N = 29). We investigated the effects of the length of the relationship between the horse and a familiar person (main caregiver), their ...
Chalder R, Housby-Skeggs N, Clark C, Pollard D, Hartley C, Blacklock B.There are a growing number of horses, ponies, and donkeys aged 15 years or older in the United Kingdom, yet there have been no studies utilising a complete ophthalmic examination to investigate the prevalence of ophthalmic pathology within this population. Objective: To investigate the prevalence of ophthalmic pathology and associations with signalment, in a convenience sample of geriatric equids in the United Kingdom. Methods: Cross sectional. Methods: Horses, ponies, and donkeys aged 15 years or older based at The Horse Trust charity underwent a full ophthalmic examination including slit...
Bampidis V, Azimonti G, Bastos ML, Christensen H, Durjava M, Kouba M, López-Alonso M, López Puente S, Marcon F, Mayo B, Pechová A, Petkova M....Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of an essential oil obtained from the oleoresin of Aiton (pine white oil, also known as turpentine oil), when used as a sensory additive in feed and water for drinking for all animal species. The Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) concluded that the essential oil under assessment is safe up to the maximum proposed use levels of 35 mg/kg for laying hens, piglets, pigs for fattening, sows, rabbits, salmonids, 50 mg/kg for veal ca...
Salamone D, Maserati M.Horse cloning by somatic cell nuclear transfer (SCNT) is an attractive scientific and commercial endeavor. Moreover, SCNT allows generating genetically identical animals from elite, aged, castrated, or deceased equine donors. Several variations in the horse SCNT method have been described, which may be useful for specific applications. This chapter describes a detailed protocol for horse cloning, thus including SCNT protocols using zona pellucida (ZP)-enclosed or ZP-free oocytes for enucleation. These SCNT protocols are under routine use for commercial equine cloning.
Yang P, Bi Q, Li Y, Liao J, Ding Y, Huang D, Luo X, Huang Y, Yao C, Zhang J, Wei W, Li Z, Meng J, Guo D.In this study, a novel pseudo-targeted peptidomics strategy, integrating the transition list generated by an in-house software (Pep-MRMer) and the retention time transfer by high-abundance ion-based retention time calibration (HAI-RT-cal), was developed to screen marker peptides of gelatins from five closely related animal species, including porcine, bovine, horse, mule, and donkey. Five marker peptides were screened from the molecular phenotypic differences of type I collagen. Furthermore, a simple and robust 10 min multiple reaction monitoring (MRM) method was established and performed well ...
Ginther OJ.Examples of research discoveries and first reports on mare reproduction by the O.J. Ginther team are (1) determined daily circulating concentrations of four hormones during the estrous cycle, (2) showed that mares can be induced to ovulate and superovulate by hormone treatment during both ovulatory and anovulatory seasons, (3) demonstrated that prostaglandin F2α was the luteolysin in mares, (4) described the mare's elaborate hormonal and biochemical mechanism for selecting the ovulatory follicle from a pool of like follicles, (5) developed the method for diagnosing fetal sex by Day 60 using l...
Sundra T, Kelty E, Rendle D.An extended-release injectable omeprazole formulation (ERIO) has become a popular treatment for equine squamous gastric disease (ESGD) and equine glandular gastric disease (EGGD) where it is available; however, published data are limited and optimal treatment regimens have not been determined. Objective: To compare effects of treatment on ESGD and EGGD when an ERIO formulation is administered at either 5- or 7-day intervals. Methods: Retrospective clinical study. Methods: Case records and gastroscopy images of horses with ESGD or EGGD treated with ERIO were reviewed. Images were anonymised and...
Lauková A, Styková E, Focková V, Maďar M.Nowadays, developed more precisious identification techniques have allowed to validate newer enterococcal species. Among them, the species Enterococcus moraviensis was also validated, at first from surface waters. However, in this study, characteristics and potential to bacteriocin production by the strain E. moraviensis EMo 1-1Nik isolated from buccal mucosa of Slovak warm-blood horse breed has been studied. BLASTn analysis allotted this strain to the species E. moraviensis with percentage identity BLASTn 16S rRNA sequence in the strain up to 100% (99.93% similarity with E. moraviensis NR1139...
Gouyet C, Ringhofer M, Yamamoto S, Jardat P, Parias C, Reigner F, Calandreau L, Lansade L.Several studies have shown that horses have the ability to cross-modally recognize humans by associating their voice with their physical appearance. However, it remains unclear whether horses are able to differentiate humans according to different criteria, such as the fact that they are women or men. Horses might recognize some human characteristics, such as sex, and use these characteristics to classify them into different categories. The aim of this study was to explore whether domesticated horses are able to cross-modally recognize women and men according to visual and auditory cues, using...
Clauss M, Codron D, Hummel J.Like other members of the odd-toed ungulates (the perissodactyls), equids once had a higher species diversity in the fossil record than they have today. This is generally explained in comparison to the enormous diversity of bovid ruminants. Theories on putative competitive disadvantages of equids include the use of a single toe as opposed to two toes per leg, the lack of a specific brain cooling (and hence water-saving) mechanism, longer gestation periods that delay reproductive output, and in particular digestive physiology. To date, there is no empirical support for the theory that equids fa...
Kappel S, Ramirez Montes De Oca MA, Collins S, Herborn K, Mendl M, Fureix C.The use of 2-dimensional representations (e.g. photographs or digital images) of real-life physical objects has been an important tool in studies of animal cognition. Horses are reported to recognise objects and individuals (conspecifics and humans) from printed photographs, but it is unclear whether image recognition is also true for digital images, e.g. computer projections. We expected that horses trained to discriminate between two real-life objects would show the same learnt response to digital images of these objects indicating that the images were perceived as objects, or representation...
Peng S, Dahlgren AR, Donnelly CG, Hales EN, Petersen JL, Bellone RR, Kalbfleisch T, Finno CJ.The genomic sequence of the horse has been available since 2009, providing critical resources for discovering important genomic variants regarding both animal health and population structures. However, to fully understand the functional implications of these variants, detailed annotation of the horse genome is required. Due to the limited availability of functional data for the equine genome, as well as the technical limitations of short-read RNA-seq, existing annotation of the equine genome contains limited information about important aspects of gene regulation, such as alternate isoforms and...
Hatami M, Qasemi-Panahi B, Daghigh Kia H, Moghaddam G, Janmohammadi H.Equine semen cryopreservation is one of the major procedures for the genetic conservation of rare and endangered genotypes. The current study was conducted to evaluate the effect of egg yolk plasma (EYP) enriched with β-carotene as an antioxidant supplement on INRA-96 extender regarding freezing Arabic stallion sperm. For this purpose, β-carotene various concentrations were utilized as a supplementary ingredient in formulating the diets of laying hens. Birds were randomly divided into four groups, fed with 0 (control), 500, 1000 and 2000 mg/kg in a supplemented diet with β-carotene. Subse...
Chapard L, Van Thillo A, Meyermans R, Gorssen W, Buys N, Janssens S.Show jumping is one of the most popular disciplines in the horse sector, which makes success in show jumping competitions an important breeding goal for many studbooks. Therefore, the genetic evaluation of show jumping performance is of major interest and this is the case for two Belgian Warmblood studbooks: the Belgian Warmblood horse and Zangersheide. In this study, first an improved phenotype for show jumping performance was developed, i.e. adjusted fence height based on a new non-arbitrary method to scale ranking and competition level, which are two major components of success in competiti...
Piras FM, Cappelletti E, Abdelgadir WA, Salamon G, Vignati S, Santagostino M, Sola L, Nergadze SG, Giulotto E.In mammals, centromeres are epigenetically specified by the histone H3 variant CENP-A and are typically associated with satellite DNA. We previously described the first example of a natural satellite-free centromere on Equus caballus chromosome 11 (ECA11) and, subsequently, on several chromosomes in other species of the genus Equus. We discovered that these satellite-free neocentromeres arose recently during evolution through centromere repositioning and/or chromosomal fusion, after inactivation of the ancestral centromere, where, in many cases, blocks of satellite sequences were maintained. H...
Ögren G, Ragnarsson S, Jansson A.Knowledge of endogenous nutrient losses is important when estimating the nutrient requirements of animals. It has been suggested that faecal endogenous phosphorus (P) losses differ between growing and adult horses, but studies on foals are scarce. In addition, studies on foals on forage-only diets with different P contents are lacking. Thus this study: (1) assessed faecal endogenous P losses in foals fed a grass haylage-only diet close to or below estimated P requirements; (2) evaluated use of serum cross-linked carboxyterminal telopeptides of type-I collagen (CTx) as a marker of bone resorpti...
Amaral A, Cebola N, Szóstek-Mioduchowska A, Rebordão MR, Kordowitzki P, Skarzynski D, Ferreira-Dias G.Myeloperoxidase is an enzyme released by neutrophils when neutrophil extracellular traps (NETs) are formed. Besides myeloperoxidase activity against pathogens, it was also linked to many diseases, including inflammatory and fibrotic ones. Endometrosis is a fibrotic disease of the mare endometrium, with a large impact on their fertility, where myeloperoxidase was shown to induce fibrosis. Noscapine is an alkaloid with a low toxicity, that has been studied as an anti-cancer drug, and more recently as an anti-fibrotic molecule. This work aims to evaluate noscapine inhibition of collagen type 1 (C...
Carmo LG, Werner LC, Michelotto PV, Daros RR.Food rewards are believed to have a positive valence in horses. The aim of this study was to assess the effect of food rewards on horse behavior before entering a horse chute, and behavior and facial movements while restrained in it. Thirteen female adult horses were brought once daily to an animal handling facility for three weeks. In week 1, baseline period, no reinforcement was applied. In weeks 2 and 3, experimental phase, half of the horses received positive reinforcement treatment after entering and remaining in the chute; the remaining horses were considered as controls (no positive rei...
Quiroz-Rothe E, Rivero JL.Combined methodologies of immunohistochemistry, histochemistry and photometric image analysis were applied: (1) to characterise control equine skeletal muscle fibres according to their myosin heavy chain (MyHC) composition and (2) to determine on a fibre-to-fibre basis the correlation between contractile [i.e. MyHC(s), myofibrillar ATPase (mATPase) and sarco(endo)plasmic reticulum Ca(2+)-ATPase (SERCA) isoforms], metabolic [i.e. succinate dehydrogenase (SDH) and alpha-glycerophosphate dehydrogenase (GPD) activities, glycogen and phospholamban (PLB) contents], and morphological [i.e. cross-sect...
Ammer H, Henschen A.The major stallion protamine was isolated from sperm cell nuclei by extraction with 6M guanidine/5% mercaptoethanol, alkylation with 4-vinylpyridine and subsequent reversed-phase high-performance liquid chromatography. The primary structure of stallion protamine was determined by N-terminal sequencing of the intact protein and of the fragments obtained from thermolysin cleavage of the S-pyridylethylated and from endoproteinase Lys-C cleavage of the S-aminoethylated protein. Stallion protamine consists of 49 amino-acid residues and shows 49% identity with all other sequenced mammalian type 1 pr...
Santos WB, Pereira CB, Maiorano AM, Arce CDS, Baldassini WA, Pereira GL, Chardulo LAL, Neto ORM, Oliveira HN, Curi RA.With the advent of genomics, significant progress has been made in the genetic improvement of livestock species, particularly through increased accuracy in predicting breeding values for selecting superior animals and the possibility of performing a high-resolution genetic scan throughout the genome of an individual. The main objectives of this study were to estimate the individual genomic inbreeding coefficient based on runs of homozygosity (F ), to identify and characterize runs of homozygosity and heterozygosity (ROH and ROHet, respectively; length and distribution) throughout the genome, a...
Walewska E, Wołodko K, Skarzynski D, Ferreira-Dias G, Galvão A.The regulation of corpus luteus (CL) luteolysis is a complex process involving a myriad of factors. Previously, we have shown the involvement of Nodal in functional luteolysis in mares. Presently, we ask the extent of which Nodal mediation of luteolysis is done through regulation of angioregression. We demonstrated the interaction between Nodal and hypoxia-inducible factor 1 α (HIF1α) and thrombospondin 1/thrombospondin receptor (TSP1/CD36) systems, could mediate angioregression during luteolysis. First, we demonstrated the inhibitory effect of Nodal on the vascular marker platelet/endotheli...
Best R, Standing R.The implementation of global positioning systems (GPSs) has become widely supported in a variety of sports, owing to the insight it provides into athlete workloads, training parameters, and playing styles. Despite widely reported use of GPS in equine settings, few studies have quantified the reliability of spatiotemporal characteristics in a dynamic environment of high-intensity gameplay. Owing to the unique game demands of Polo for both riders and horses, this study aimed to assess the interunit reliability between a traditional GPS placement between the shoulder blades and a Polo-specific pl...
Almadhidi J, Seralini GE, Fresnel J, Silberzahn P, Gaillard JL.Estrogens are the major steroids produced by equine gonads. To identify the cells responsible for estrogen synthesis, an antiserum against purified equine testicular cytochrome P450 aromatase was produced in rabbits. The reactivity and specificity of the antiserum were assessed by ELISA, immunoblot analysis, and immunoneutralization studies. Immunofluorescence microscopy demonstrated that in the male gonad, cytochrome P450 aromatase (P450arom) was localized in the interstitial tissue, whereas, under the experimental conditions used, the Sertoli and germ cells did not show any specific staining...
Valentine BA.Gross and histopathologic evaluation of skeletal muscle was performed in 229 equids (217 horses, 8 ponies, 3 donkeys, and 1 mule) 1 year of age or older undergoing postmortem examination at Oregon State University in a 2.5-year period. Animals were evaluated for grossly evident muscle lesions, and muscle samples were fixed in formalin, processed routinely, and stained with hematoxylin and eosin (HE) and periodic acid-Schiff (PAS) for glycogen. Muscle lesions were detected in 149 animals (65%). Chronic myopathic change (excessive fiber size variation and internal nuclei) was evaluated in horses...
Dorey NR, Conover AM, Udell MA.The ability of many domesticated animals to follow human pointing gestures to locate hidden food has led to scientific debate on the relative importance of domestication and individual experience on the origins and development of this capacity. To further explore this question, we examined the influence of different prior training histories/methods on the ability of horses (Equus ferus caballus) to follow a momentary distal point. Ten horses previously trained using one of two methods (Parelli™ natural horsemanship or traditional horse training) were tested using a standard object choice tas...
Winton CL, McMahon R, Hegarty MJ, McEwan NR, Davies-Morel MCG, Morgan C, Nash DM.The UK and Ireland have many native pony breeds with historical and cultural importance as well as being a source of uncharacterized genetic diversity. However, there is a lack of comprehensive research investigating their genetic diversity and phylogenetic interrelationships. Many studies contain a limited number of pony breeds or small sample sizes for these breeds. This may result in erroneous grouping of pony breeds that otherwise have intricate interrelationships with each other and are not evaluated correctly when placed as a token subset of a larger dataset. This is the first study that...
Rivero JL, Serrano AL, Quiroz-Rothe E, Aguilera-Tejero E.The objective of this study was to investigate the relationship between kinematic variables and muscle characteristics by determining (1) if heavy endurance training alters these variables and (2) if such modifications occur in a coordinated manner. Fifteen Andalusian stallions age 41-45 months were used. Five horses were used as controls and 10 horses underwent a training programme based on aerobic exercise for 8 months. Intensity of exercise was adjusted individually for each horse according to a standardised exercise test. Stride kinematic characteristics at the trot were analysed by videog...
Colgan SA, Hecker AT, Kirker-Head CA, Hayes WC.To determine risk of failure of the Synthes 4.5-mm cannulated screw system instrumentation in equine bone and to compare its application with the Synthes 4.5-mm standard cortex screw system. Methods: The maximum insertion torque of the cannulated and standard cortex screw systems were compared with the ultimate torsional strengths of the equipment. Pullout strength and ultimate tensile load of cannulated and standard cortex screws were also determined. Methods: Paired equine cadaver third metacarpal and third carpal bones. Methods: Maximum insertion torque and ultimate torsional strengths were...
Panarace M, Pellegrini RO, Basualdo MO, Belé M, Ursino DA, Cisterna R, Desimone G, Rodríguez E, Medina MJ.Flow cytometry sex-sorting technology was developed in 1989. However, it is only the bovine species in which offspring of the desired sex are obtained at a commercial level. The aim of the present work was to evaluate efficiency parameters when using fresh sexed semen in a large-scale equine commercial embryo transfer program. During the 2009, 2010 and 2011 breeding seasons, 938 synchronized cycles were artificially inseminated. One hundred (10.6%) mares failed to ovulate, and for the remaining 838 useable cycles, 887 doses of sexed semen were used, representing 1.06 doses per cycle. In genera...
Barreto RSN, Romagnolli P, Mess AM, Rigoglio NN, Sasahara THC, Simões LS, Fratini P, Matias GSS, Jacob JCF, Gastal EL, Miglino MA.In horses, pregnancy is characterized by high levels of maternal estrogens that are produced largely by the interstitial tissue inside the gonads of the offspring, associated with a physiological gonadal hyperplasia, that is uncommon in other species. However, a detailed structural-functional understanding of the early stages of gonadal development and hyperplasia has remained elusive in horse pregnancy because of the lack of substantial data. The goal of this study was to describe the genital organs' development in 19 early horse embryos and fetuses (days 20-140 of gestation) of both sexes by...
Bażanów B, Pawęska JT, Pogorzelska A, Florek M, Frącka A, Gębarowski T, Chwirot W, Stygar D.Huculs () are an old breed of primitive mountain horses, originating from the Carpathian Mountains. To the best of our knowledge, data concerning the epidemiology of viral infections observed within this breed are sparse. The objective of this study was to estimate the serological status of a semi-isolated, unvaccinated Hucul herd, with respect to both common equine viral infections and horse-infecting arboviruses, the presence of which was previously reported in Poland. Twenty horses of the Hucul breed, living in a remote area in Poland, were studied in 2018 from March to May. Using nasal sec...
Silvers BL, Leatherwood JL, Arnold CE, Nielsen BD, Huseman CJ, Dominguez BJ, Glass KG, Martinez RE, Much ML, Bradbery AN.While beneficial in rehabilitation, aquatic exercise effects on cartilage and bone metabolism in young, healthy horses has not been well described. Therefore, 30 Quarter Horse yearlings (343 ± 28 kg; 496 ± 12 d of age) were stratified by age, body weight (BW), and sex and randomly assigned to 1 of 3 treatments for 140-d to evaluate effects of aquatic, dry, or no exercise on bone and cartilage metabolism in young horses transitioning to an advanced workload. Treatments included nonexercise control (CON; n = 10), dry treadmill (DRY; n = 10), or aquatic treadmill exercise (H2O; n = 10; water: 6...
Yin NH, McCarthy I, Birch HL.Human Achilles tendon is composed of three smaller sub-tendons and exhibits non-uniform internal displacements, which decline with age and after injury, suggesting a potential role in the development of tendinopathies. Studying internal sliding behaviour is therefore important but difficult in human Achilles tendon. Here we propose the equine deep digital flexor tendon (DDFT) and its accessory ligament (AL) as a model to understand the sliding mechanism. The AL-DDFT has a comparable sub-bundle structure, is subjected to high and frequent asymmetric loads and is a natural site of injury similar...
Murray MJ, Mahaffey EA.Specimens of grossly normal gastric stratified squamous epithelial mucosa adjacent to the margo plicatus on the right side and along the greater curvature were obtained from 7 foetuses, 10 term foals and 12 foals 2-35 days old. Gastric squamous epithelium from the foetuses changed markedly during gestation. At 150-270 days, the epithelium was 8-10 cells thick, with a single layer of basal cells. Epithelial cells were polyhedral and had abundant clear or slightly stained cytoplasm. In the 300-day foetus the basal layer was thicker, epithelial cells were polyhedral, and there was a flattened 1 c...
Jaqueth AL, Hathaway M, Catalano DN, Linders NC, Mottet R, Martinson KL.Social media are an ever-present part of daily life and for researchers and may be a useful platform to increase potential participant pools for Web-based surveys. Although survey usage to evaluate practices in the equine community is not new, the use of social media to advertise and enhance the usage of Web-based surveys is novel. In 2018, the University of Minnesota (UMN) equine Extension program developed and administered two Web-based surveys through the UMN equine Extension Facebook page and monthly e-newsletter. Surveys focused on industry practices and motivating factors behind the usag...
Yovich JV, Gould DH, LeCouteur RA.The distribution and morphology of fibrous astrocytes in the cervical spinal cord of normal horses and horses with chronic compressive myelopathy were demonstrated using immunohistochemical staining for glial fibrillary acidic protein. In the spinal cord from normal horses, astrocytes with stellate cell bodies and short processes were irregularly distributed in grey matter. In the white matter, their cell bodies were small and angular in areas adjacent to grey matter and larger and more stellate-shaped in the subpial area. Astrocyte processes were fine, and evenly distributed in a predominantl...
Information on equine infectious anaemia (EIA) in mules, including those with an equivocal reaction in agar gel immunodiffusion test (AGIDT), is scarce. For this, a study was conducted to evaluate the clinical, viral loads and pathological findings of two groups of naturally infected asymptomatic mules, respectively with a negative/equivocal and positive AGIDT reactivity, which were subjected to pharmacological immune suppression (IS). A non-infected control was included in the study that remained negative during the observation period. Throughout the whole study, even repeated episodes of rec...
Fleurance G, Duncan P, Fritz H, Gordon IJ, Grenier-Loustalot MF.The spatial heterogeneity of grasslands determines the abundance and quality of food resources for grazing animals. As plants mature, they increase in mass, which allows greater instantaneous intake rates, but the cell wall concentrations increase too, reducing diet quality. In ruminants, daily intake rates are often constrained by the time needed for the ingesta to pass through the rumen, which is influenced by the rate of digestion. It has been suggested that the digestive constraint should have much less effect on hindgut fermenters such as equids. Horses play an increasing role in the mana...
Cho HW, Shin S, Song KD, Park JW, Choi JY, Lee HK, Cho BW.The adrenergic receptor beta 2 (ADRB2) plays a role in various physiological responses of the muscle to exercise, such as contraction and relaxation. Given its important role in muscle function, we investigated the structure of the horse ADRB2 gene and its expression pattern after exercise to determine if it can serve as a putative biomarker for recovery. Evolutionary analyses using synonymous and non-synonymous mutation ratios, were compared with other species (human, chimpanzee, mouse, rat, cow, pig, chicken, dog, and cat), and revealed the occurrence of positive selection in the horse ADRB2...
Dobrinski I, Thomas PG, Ball BA.Two bioassays were used to evaluate the interaction of fresh and cryopreserved equine semen with oviductal epithelial cells (OEC) and with the zona pellucida (ZP). Split ejaculates were either stored at room temperature or frozen and thawed. In experiment 1, progressive motility and membrane integrity were evaluated for each treatment. Fluorescent labeled spermatozoa were cocultured with monolayers of OEC for 30 minutes, and the number of sperm attached to OEC was counted by fluorescence microscopy and analysis of digitized images. Motility of spermatozoa attached to OEC was observed at 0.5, 3...
Ruohoniemi M, Kärkkäinen M, Tervahartiala P.Six Finnhorse cadaver forefeet were selected to represent radiographically different types and grades of ossification of the collateral cartilages of the distal phalanx. These cartilages and adjacent tissues were evaluated with computed tomography (CT) and high field magnetic resonance imaging (MRI). In CT the internal structure of the cartilages was consistent, but in MRI some differences were noted. The shape of the collateral cartilages and their ligamentous attachments varied. The border between ossified and non-ossified cartilage appeared distinct, with considerable variation in the exten...
Park DH, Plapp BV.The E and S isoenzymes of horse liver alcohol dehydrogenase differ by 10 amino acid residues, but only the S isoenzyme is active on 3 beta-hydroxysteroids. This functional difference was correlated to the differences in structures of the isoenzymes by characterizing a series of chimeric enzymes, which could represent intermediates in the evolution of catalytic activity. Deletion of Asp-115 from the E isoenzyme created the E/D115 delta enzyme that is active on steroids. The deletion alters the substrate binding pocket by moving Leu-116, which sterically hinders binding of steroids in the E isoe...
Park JW, Song KD, Kim NY, Choi JY, Hong SA, Oh JH, Kim SW, Lee JH, Park TS, Kim JK, Kim JG, Cho BW.Since athletic performance is a most importance trait in horses, most research focused on physiological and physical studies of horse athletic abilities. In contrast, the molecular analysis as well as the regulatory pathway studies remain insufficient for evaluation and prediction of horse athletic abilities. In our previous study, we identified receptor tyrosine kinase () gene which was expressed as alternative spliced isoforms in skeletal muscle during exercise. In the present study, we validated two alternative splicing transcripts (named as for long form and for short form) in equine s...
Hoshino M, Kawata Y, Goto Y.GroEL interacts with proteins in denatured states and promotes their efficient folding. To understand the conformational features required for the substrate, we studied the interactions of GroEL with various derivatives of horse cytochrome c including porphyrin-cytochrome c, apo-cytochrome c, and the three fragments containing the heme group, i.e. fragments 1-65, 1-38 and 11-21. Size-exclusion chromatography was performed, taking advantage of the heme absorption of the fluorescence label. Under low-salt conditions, significant binding to GroEL was observed for porphyrin-cytochrome c, apo-cytoc...
Hepperger C, Mayer A, Merz J, Vanderwall DK, Dietzel S.Whether chromosome sets inherited from father and mother occupy separate spaces in the cell nucleus is a question first asked over 110 years ago. Recently, the nuclear organization of the genome has come increasingly into focus as an important level of epigenetic regulation. In this context, it is indispensable to know whether or not parental genomes are spatially separated. Genome separation had been demonstrated for plant hybrids and for the early mammalian embryo. Conclusive studies for somatic mammalian cell nuclei are lacking because homologous chromosomes from the two parents cannot be d...
Burns TE, Clayton HM.The objectives were to compare the temporal characteristics of canter pirouette strides with collected canter strides in elite dressage horses, and to determine whether the stride kinematics of the canter pirouettes fulfilled the requirements specified in the Federation Equestre Internationale Rules for Dressage Events. Eleven horses were videotaped (60 fields/s) during the individual medal competition at the 1992 Olympic Games. Temporal variables were extracted from the videotapes using standard methods. Two strides were analysed on each of the left and right leads and these were pooled to gi...
