The topic of muscle in horses encompasses the study of equine muscle structure, function, and physiology. Muscles in horses are responsible for movement, posture, and various metabolic processes. They are composed of muscle fibers that contract and relax to produce motion and generate force. Research in this area often focuses on muscle development, adaptation to exercise, and the impact of nutrition and training on muscle performance. Conditions such as muscle fatigue, injury, and disorders like equine exertional rhabdomyolysis are also explored. This page compiles peer-reviewed research studies and scholarly articles that investigate the anatomy, physiology, and clinical aspects of muscle in equine species.
Moura RA, Bisiau A, Freeman D, Grosche A, Azevedo TMBPR, Vettorato E, Portela DA, Chiavaccini L.Perianaesthetic fluid therapy can influence oxygen delivery and tissue oxygenation, yet the optimal fluid rate in horses remains undefined. Objective: To compare two fluid strategies on peripheral tissue oxygenation (StO) and cardiorespiratory variables in isoflurane-anaesthetised horses. Methods: Randomised, controlled, experimental design with two independent groups. Methods: Sixteen euvolemic adult horses undergoing coeliotomy were anaesthetised with xylazine, ketamine, and midazolam, maintained on isoflurane with lidocaine infusion, and randomised to lactated Ringer's solution at 2.5 mL/...
Harness racing performance in horses is a complex polygenic trait influenced by genetic background, breeding history, training, and environment. Understanding genomic patterns shaped by long-term artificial selection provides insights into performance-related traits and breed-specific genomic variation. Objective: This study aimed to characterize genomic differentiation, population structure, and candidate genomic regions potentially influenced by historical selection in Standardbred horses using comparative whole-genome sequencing involving diverse horse breeds. Methods: Whole-genome sequenci...
Physical exercise induces physiological adaptations associated with increased muscular activity, metabolic heat production, and changes in body surface temperature. Infrared thermography has emerged as a non-invasive technique for assessing these thermal responses in horses. The present study aimed to evaluate the ability of infrared thermography to detect changes in mean local surface temperature and to qualitatively assess alterations in thermal distribution patterns following treadmill exercise. Methods: Three clinically healthy Warmblood horses were monitored over 10 consecutive training s...
Meyer HL, Tang Y, Wang Y, Kingston JK, Brown JA, Sides RH, Bayly WM.To document changes in acid-base and ion balance during exercise following furosemide administration and to relate them to performance. Unassigned: 6 fit Thoroughbred horses received 0.5 mg/kg IV furosemide (F) or a placebo (C) in randomized crossover order 4 hours before galloping to fatigue on a treadmill at the speed equated with an oxygen demand of 1.15 X maximum oxygen consumption (V˙o2max). Arterial and mixed venous blood was sampled before treatment, preexercise, after 2-minute warm-up, at fatigue, and 1 minute postexercise. The pH, temperature-corrected Pco2, total CO2, and sodium, po...
Beaussart M, Perrin R, Marunova E, Moraine F, Fourteau D, Blake R.We aimed to investigate the effects of an 8-week 448 kHz radiofrequency (RF) on multifidus cross-sectional area (CSA) and thoracolumbar differential range of motion (ROM). Eight Thoroughbred horseball horses received four RF treatments (T9-L6) at 2-week intervals. Multifidus CSA (T10-L5) and differential spinal ROM between the withers (W), T13, T18, L3 and sacrum (S) were measured before treatment, immediately after the first session, 24 h after the first session, and at 8 weeks (15 days after the last session). Linear mixed models with Tukey post hoc comparisons were used. Significant effects...
Schütz D, Shield S, Patel A.Cursorial quadrupeds employ distinct mechanical strategies for high-speed locomotion, with felids relying more strongly on axial motion than equids. The biomechanical role of spinal stiffness, however, is difficult to isolate experimentally because it is coupled to limb mechanics, morphology, and coordination. Here, we used comparative three-dimensional trajectory optimization to test how spinal stiffness influences gait mechanics and actuation-demand proxies in simulated cheetah-like and horse-like galloping. Homologous cheetah and horse models were evaluated across spinal-stiffness values, p...
Grzegorczyk W, Soroko-Dubrovina M, Dobrowolski M, Grabska D, Dudek KD.Capacitive and resistive electric transfer (TECAR) therapy is increasingly used in equine physiotherapy; however, objective evidence regarding its immediate effects on equine back muscles remains limited. This pilot study aimed to evaluate the effects of TECAR therapy on body surface temperature and muscle tone of the longissimus dorsi muscle in Thoroughbred racehorses. A randomized, single-blinded experimental study was conducted in 20 clinically healthy Thoroughbred racehorses aged 2-3 years. Horses were randomly assigned to either a TECAR treatment group ( = 10) or a sham-treatment control ...
Su Y, Ren W, Zeng Y, Meng J, Yao X, Wang J.Skeletal muscle serves as the direct executor of movement, and the proliferation and migration capacities of its constituent cells represent the key physiological foundation determining equine endurance and speed. Previous whole-transcriptome analysis has shown that Insulin-like Growth Factor 1 () is significantly upregulated in following racing and is involved in the PI3K-Akt signaling pathway; however, its specific regulatory mechanism in equine skeletal muscle cells remains unclear. This study utilized primary equine skeletal muscle cells as a model. By constructing an overexpression plas...
Kallmyr-Mack A, Hellings IR, Press CM, Ibrahim L, van Loon G, Fintl C.Myocardial sleeves (MSs) are thin layers of cardiac muscle that extend from the atria into the caval and pulmonary veins. They are recognised as important structures in both initiating and maintaining atrial tachycardia, and especially atrial fibrillation (AF), which is the most clinically important cardiac arrhythmia in horses with a reported prevalence of 1.3-2% in Standardbred racehorses. In contrast, the Norwegian-Swedish Coldblooded Trotter (NSCT) has a much lower prevalence of AF despite experiencing similar physical demands. The purpose of this study was to describe the macro-, and micr...
Scheibenpflug M.In-hand training of piaffe and passage via tactile leg stimulation (Handarbeit mit Touchieren) is widely practised in dressage, yet consistently produces horses that elevate their legs without achieving collection - a pattern termed Schenkelgänger (leg-movers) in classical German equitation. Based on published kinetic, kinematic, and electromyographic literature, this review argues that tactile leg stimulation activates the spinal nociceptive withdrawal reflex, an unloading movement mechanistically opposed to the elastic tendon rebound and ventral muscular chain activation that define true co...
Davie AJ, Beavers R, Denham J.This study evaluated the reliability of five treadmill protocols that assess heart rate (HR) and blood lactate (Bla) responses in Thoroughbred horses to determine their effectiveness in serving as potential tools for monitoring fitness and the wellbeing of racehorses. Of the five exercise tests, four consisted of repeated interval gallops at constant speeds (8 m/s and 10 m/s) and grade (6°) and one test of a continuous gallop at constant speeds (8 m/s) and grade (6°). Eight hundred and twenty-three gallops in total were performed by 64 horses. The test-retest reliability and absolute agreeme...
Dubey JP, Gupta A, Rosenthal BM.Uncertainty shrouds the number and identity of the species of Sarcocystis infecting horses in the United States. Horses are intermediate hosts for Sarcocystis fayeri, for which the domestic dog is the definitive host. Clinical signs and lesions associated with S. fayeri are not defined. Granulomatous myositis, especially involving the chest and dysphagia, is one of the clinical presentations associated with S. fayeri infections. Whether S. fayeri is the sole species that forms sarcocysts in equine muscles in the United States is not clear. Little is known of the molecular diagnosis of Sarcocys...
Suzuki S, Norita A, Asaoka Y, Fukuhara A, Ishikawa M, Kobayashi R, Ishiguro A.Quadruped animals exhibit various gait patterns and switch from one to another depending on their speed. These gait patterns involve complex whole-body coordination and are mainly controlled by a distributed neural network consisting of central pattern generators (CPGs) and peripheral sensory feedback. However, how these neural networks generate various types of whole-body coordination remains unclear. Here, we focus on horse locomotion and present a neural network model that reproduces walk-trot-gallop transitions by changing only a single parameter related to speed. This model uses ground re...
Wesolowski LT, Artman JL, Semanchik PL, Carson CP, Fenger CK, Pagan JD, Valberg SJ, White-Springer SH.Recurrent Exertional Rhabdomyolysis (RER) is a skeletal muscle disease that can intermittently impede careers of equine athletes. Manifesting as episodes of muscular stiffness and degeneration, RER causes lost training and competition days. RER is associated with abnormal intracellular calcium (Ca) regulation. Calcium released from the sarcoplasmic reticulum to initiate contraction may also be transported into mitochondria, which impacts energy production. RER-susceptible horses exhibit down-regulated mitochondrial proteins but upregulated mitochondrial genes. Thus, mitochondrial function may ...
Takahashi K, Mukai K, Shirai T, Ebisuda Y, Sugiyama F, Yoshida T, Hatta H, Kitaoka Y.This study investigated whether different pacing patterns during high-intensity exercise elicit distinct transcriptional responses in equine skeletal muscle. Eight Thoroughbred horses completed two treadmill exercise sessions in a randomized crossover design. In the positive-pacing condition, horses exercised at 110% maximal O₂ uptake (V˙O₂max) for 1 min followed by 90% V˙O₂max for 1 min, whereas in the negative-pacing condition, the order was reversed. At 4 h after exercise, the positive-pacing protocol resulted in upregulation of 1,989 genes and downregulation of 840 genes, whereas t...
Tomaini MC, Heck DPO, Moreira BC, Lima LR, Marson RA, Almeida FQ.This study aimed to evaluate electromyographic and kinematic parameters of the thoracic and pelvic limbs of horses at a walk and trot on a treadmill. Eleven Brazilian Sport Horses trained for Eventing were assessed in a completely randomized design under two conditions: walk (1.8Â m/s) and trot (3.6Â m/s). Horses were evaluated on a high-speed treadmill using surface electromyography (sEMG) and kinematic analysis. sEMG was performed bilaterally on the mm. extensor carpi radialis and mm. flexor carpi ulnaris; bilateral muscles of the pelvic limb: mm. tensor fascia latae and mm. biceps femoris u...
Xue Y, Luo P, Shen Z, Meng C, Yao X, Meng J, Ren W, Wang T, Zeng Y.Training induces sweat morphology changes in horses from muddy sweat (MS) to foamy sweat (FS) and clear sweat (CS), reflecting physiological adaptation. However, the metabolic mechanisms linking sweat phenotypes to systemic amino acid dynamics remain unclear. This study integrated sweat untargeted metabolomics and plasma amino acid targeted metabolomics to reveal coordinated metabolic remodeling. Six 2-year-old horse stallions underwent 10-week training. Plasma and sweat were sampled pre- and post-race at each stage. LC-MS/MS and UHPLC-MS/MS were used for sweat metabolome and plasma amino aci...
Dockalová H, Zalesakova D, Batik DB, Batik A, Kacetlova D, Horky P.Physiological adaptation to training in young sport horses remains incompletely characterized, particularly during standardized preparation for breeding licensing. Objective: The aim of this study was to evaluate cardiovascular and plasma biochemical responses to acute exercise and long-term training in three-year-old Czech Warmblood stallions during standardized free jumping exercise. Methods: Thirteen Czech Warmblood stallions were monitored over a 112-day training period. Heart rate parameters (minimum, maximum, and mean) were recorded during standardized free jumping tests. Plasma biochemi...
Li Z, Ren W, Wang R, Li L, Ma S, Su Y, Shan D, Huang Q, Wang J.Although the Kazakh horse is a dual-purpose breed renowned for both milk and meat production, the extent to which surgical castration alters gene expression in its muscles has not yet been fully elucidated. In this study, left longissimus dorsi muscle (LDM) samples were obtained from six Kazakh stallions (W group) and six Kazakh geldings (S group) to comparatively evaluate meat quality parameters, examine histological characteristics in tissue sections, and apply transcriptomic profiling to comprehensively explore the principal regulatory pathways and candidate genes through which surgical cas...
The horse represents one of the most physiologically specialized athletic mammals, capable of sustaining both high-intensity and prolonged exercise. Central to this remarkable performance capacity is the metabolic adaptability of skeletal muscle and its mitochondrial network. This narrative review synthesizes current evidence from equine, human, and rodent studies on exercise-induced mitochondrial remodeling in equine skeletal muscle. A comprehensive literature search was conducted across PubMed, Web of Science, and Scopus using terms related to equine exercise physiology, mitochondrial biolog...
Bou T, Ding W, Gong W, Li Z, Shi X, Dugarjaviin M, Bai D, Yang L.The Grassland Xichun horse is an emerging crossbred population developed from Xilingol mares and Thoroughbred stallions in Inner Mongolia, China, yet its blood physiological profile has not been systematically characterized. In this study, we compared 32 hematological and serum biochemical parameters between 177 Grassland Xichun horses and 35 Xilingol horses maintained under the same extensive grazing conditions. Following Benjamini-Hochberg FDR correction, 17 of 32 parameters differed significantly between breeds. Grassland Xichun horses showed markedly higher RBC count (9.145 vs 7.905 × 10Â...
Liu Y, Wang X, Tan G, Dugarjaviina M, Zhang X.Horse meat is a high-quality protein source. A total of 50 two-year-old male horses with similar body weights (300 ± 50 kg) were used: 30 for regional comparison (10 each from Bulgan province region of Mongolia (BPM), Tuv province region of Mongolia (TPM), and Inner Mongolia region of China (IMC)) and an additional 20 from the IMC region for muscle-site analysis. To elucidate the molecular mechanisms underlying regional and muscle-site differences in the meat quality of Mongolian horses, with particular emphasis on tenderness, this study analyzed chemical composition, minerals, fatty acids, a...
Nascimento C, Santos C, Walton M, Gonçalves T, Freire G, Nicolau M, Silvestre F, Simões J, Borges J, Pires N, Filho HM, Clayton H, Coelho C.The correct prescription of aquatic treadmill training for equine athletes depends on understanding the muscular changes generated by working in the water. Objective: The aim of this study was to test the hypothesis that the inclusion of a water treadmill in a routine training protocol would alter muscle mass of show jumping horses. Methods: Six fit-to-compete horses were trained for 10 weeks with a water treadmill (twice a week, 20 minutes, water level at the carpus), in addition to regular physical exercise. Body composition, infrared thermography (IRT) of propulsive muscles (m. brachiocepha...
Liu Y, Wang X, Gong S, Dugarjaviina M, Zhang X.This study aims to conduct a comparative analysis of the quality and flavor of meat from four categories of Mongolian horses (Wushen, Baicha, Barhu, and Ujimqin). Physicochemical indicators, electronic nose, electronic tongue, and lipidomics were used to characterize meat quality and flavor and to screen for differential markers. Results showed that Wushen Horses had the highest pH, serine, glutamic acid, total free amino acids (∑FAA), total non-essential amino acids (∑NEAA), total amino acids (∑TAA), NEAA/TAA, W2S sensor response, umami and richness values, and had the lowest cooking lo...
Chang X, Peng J, Zhang Z, Zhai M, Chu H, Yao R, Luo P, Yao X, Ren W, Zeng Y.This study integrated echocardiography with widely targeted metabolomics to decipher how plasma metabolic dynamics couple with cardiac geometry in Yili horses during incremental treadmill exercise. Nine speed-type horses underwent a graded exercise test (6% incline; 0 to 9 m/s). Jugular venous blood samples collected at rest (0 m/s) and at 3, 5, 7, and 9 m/s were profiled by LC-MS, and Pearson correlation analysis was applied to relate differentially expressed metabolites (DEMs) to twenty echocardiographic structural indices. A core set of 314 shared DEMs (124 upregulated, 190 downregulated) w...
Nascimento RCMD, Guedes EAB, Silva RBD, Cerqueira ITI, Freire CCDS, Câmara DR, Moura FA, Escodro PB, Goulart MOF.Vaquejada (VQ) is a traditional Brazilian sport demanding high performance from Quarter Horse (QH) athletes. This study aimed to identify modifications in hematological, biochemical, inflammatory, and oxidative stress biomarkers associated with VQ training, comparing conditioned and non-conditioned horses. Blood samples were collected at rest from 70 healthy QH horses: 60 athletes (VQ-conditioned athlete group-AG) and 10 sedentary controls (breeding horses-CG). Using Linear Mixed Models alongside comprehensive hematological and biochemical analyses, the study found that AG horses exhibited an ...
Ribeiro G, AgrÃcola R, Sanchez MMF, Ramos FR, Borges J, Abrantes J, Prazeres J.To evaluate the feasibility of a hand-held myotometry device for measuring the biomechanical parameters (frequency, stiffness, and decrement) of the longissimus dorsi muscle in the thoracolumbar region of healthy horses. Unassigned: Data were obtained from 50 adult horses. The biomechanical parameters were measured using a MyotonPRO device in triple-scan mode. Measurements were recorded on both sides, with the horses standing square. The analysis focused on whether there were differences between the sides and correlations between the variables. Unassigned: The mean muscle frequency (hertz) was...
Sun W, Shen Z, Cairen D, Luo P, Yao X, Meng J, Zeng Y.Body measurement traits are a direct production indicator reflecting growth status and guiding genetic selection. Identifying molecular markers associated with body measurement traits could accelerate animal breeding programs. The Yanqi horse, an important indigenous breed in Xinjiang, is primarily distributed in the Bayingolin Mongol Autonomous Prefecture. However, molecular markers linked to body measurement traits in Yanqi horses remain uncharacterized. In the present study, whole-genome resequencing was performed on 183 Yanqi horses, yielding 13,366,672 single-nucleotide polymorphisms (SNP...
de Lima LRS, Amorim CF, Vieira MF, Arnhold E, Scoz RD, Brandstetter LRG, Costa LCS, Barcelos KMC.Background: Hippotherapy is a therapeutic intervention that uses the horse as a biomechanical and sensorimotor agent to promote rehabilitation in individuals with physical and neurological disabilities. Depending on patient needs, riding may be performed with a single rider or with double riding, in which a therapist accompanies the practitioner on the horse. However, the effects of these riding configurations on equine trunk muscle activity remain poorly understood, despite their relevance for both horse welfare and the quality of therapeutic stimuli delivered to the patient.Methods: Nine cli...
Scheibenpflug M, Haussler KK.Equine lameness diagnosis is dominated by a joint- and tendon-centric paradigm. The standard diagnostic algorithm relies on gait observation, perineural and intrasynovial anesthesia, and cross-sectional imaging. It is directed almost exclusively at skeletal and articular structures. Myofascial trigger points (MTrPs) are hypersensitive, hyperirritable loci within taut bands of skeletal muscle. They produce local and referred pain on compression or contraction. In horses, MTrPs are a clinically relevant but systematically overlooked source of primary lameness. This review synthesises evidence fr...
Heizmann CW, Berchtold MW, Rowlerson AM.The physiological role of the Ca2+-binding protein parvalbumin in skeletal muscle has been investigated by measuring the parvalbumin content by HPLC in a variety of mammalian muscles, including man, and comparing the results with the respective muscle relaxation properties and fiber type compositions. The parvalbumin concentrations were highest in the skeletal muscles of the smallest animal investigated (mouse, gastrocnemius: 4.9 g/kg), which has the highest relaxation speed, and lowest in the larger animals (horse, deep gluteal muscle: less than or equal to 0.001 g/kg) and man (vastus, tricep...
Biewener AA.The stresses acting in muscle-tendon units and ligaments of the forelimb and hindlimb of horses were determined over a range of speed and gait based on recordings of ground reaction forces and limb kinematics. Maximum stresses of 40-50 MPa were calculated to act in several of the principal forelimb (superficial digital flexor (SDF), deep digital flexor (DDF), ulnaris lateralis (UL) and flexor carpi ulnaris/radialis (FCU/R)) and hindlimb tendons (plantaris, DDF) at the fastest galloping speeds recorded (up to 7.4 m s-1). Smaller stresses were found for the gastrocnemius (GAST) tendon (30 MPa) a...
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...
Hill EW, McGivney BA, Gu J, Whiston R, Machugh DE.Thoroughbred horses have been selected for traits contributing to speed and stamina for centuries. It is widely recognized that inherited variation in physical and physiological characteristics is responsible for variation in individual aptitude for race distance, and that muscle phenotypes in particular are important. Results: A genome-wide SNP-association study for optimum racing distance was performed using the EquineSNP50 Bead Chip genotyping array in a cohort of n = 118 elite Thoroughbred racehorses divergent for race distance aptitude. In a cohort-based association test we evaluated geno...
Hosnedlova B, Kepinska M, Skalickova S, Fernandez C, Ruttkay-Nedecky B, Malevu TD, Sochor J, Baron M, Melcova M, Zidkova J, Kizek R.Selenium is an essential trace element important for many physiological processes, especially for the functions of immune and reproductive systems, metabolism of thyroid hormones, as well as antioxidant defense. Selenium deficiency is usually manifested by an increased incidence of retention of placenta, metritis, mastitis, aborts, lowering fertility and increased susceptibility to infections. In calves, lambs and kids, the selenium deficiency demonstrates by WMD (white muscle disease), in foals and donkey foals, it is associated with incidence of WMD and yellow fat disease, and in pigs it cau...
Gu J, Orr N, Park SD, Katz LM, Sulimova G, MacHugh DE, Hill EW.Thoroughbred horses have been selected for exceptional racing performance resulting in system-wide structural and functional adaptations contributing to elite athletic phenotypes. Because selection has been recent and intense in a closed population that stems from a small number of founder animals Thoroughbreds represent a unique population within which to identify genomic contributions to exercise-related traits. Employing a population genetics-based hitchhiking mapping approach we performed a genome scan using 394 autosomal and X chromosome microsatellite loci and identified positively selec...
Wilson AM, McGuigan MP, Su A, van Den Bogert AJ.The muscular work of galloping in horses is halved by storing and returning elastic strain energy in spring-like muscle-tendon units.These make the legs act like a child's pogo stick that is tuned to stretch and recoil at 2.5 strides per second. This mechanism is optimized by unique musculoskeletal adaptations: the digital flexor muscles have extremely short fibres and significant passive properties, whereas the tendons are very long and span several joints. Length change occurs by a stretching of the spring-like digital flexor tendons rather than through energetically expensive length changes...
Park KD, Park J, Ko J, Kim BC, Kim HS, Ahn K, Do KT, Choi H, Kim HM, Song S, Lee S, Jho S, Kong HS, Yang YM, Jhun BH, Kim C, Kim TH, Hwang S, Bhak J....Thoroughbred horses are the most expensive domestic animals, and their running ability and knowledge about their muscle-related diseases are important in animal genetics. While the horse reference genome is available, there has been no large-scale functional annotation of the genome using expressed genes derived from transcriptomes. Results: We present a large-scale analysis of whole transcriptome data. We sequenced the whole mRNA from the blood and muscle tissues of six thoroughbred horses before and after exercise. By comparing current genome annotations, we identified 32,361 unigene cluster...
To evaluate the effect of hippotherapy (physical therapy utilizing the movement of a horse) on muscle activity in children with spastic cerebral palsy. Methods: Pretest/post-test control group. Methods: Therapeutic Riding of Tucson (TROT), Tucson, AZ. Methods: Fifteen (15) children ranging from 4 to 12 years of age diagnosed with spastic cerebral palsy. Methods: Children meeting inclusion criteria were randomized to either 8 minutes of hippotherapy or 8 minutes astride a stationary barrel. Methods: Remote surface electromyography (EMG) was used to measure muscle activity of the trunk and upper...
Belaunzaran X, Bessa RJ, LavÃn P, Mantecón AR, Kramer JK, Aldai N.The consumption of horse-meat is currently not popular in most countries, but because of its availability and recognized nutritional value consumption is slowly increasing in several western European countries based on claims that it could be an alternative red meat. In this review, horse-meat production, trade and supply values have been summarized. In addition, the advantage of horse production is noted because of its lower methane emissions and increased uptake, particularly of n-3 polyunsaturated fatty acids (PUFAs), which is based on its digestive physiology. Of particular interest in thi...
McGuigan MP, Wilson AM.A horse's legs are compressed during the stance phase, storing and then returning elastic strain energy in spring-like muscle-tendon units. The arrangement of the muscle-tendon units around the lever-like joints means that as the leg shortens the muscle-tendon units are stretched. The forelimb anatomy means that the leg can be conceptually divided into two springs: the proximal spring, from the scapula to the elbow, and the distal spring, from the elbow to the foot. In this paper we report the results of a series of experiments testing the hypothesis that there is minimal scope for muscle cont...
Carraro U, Kern H, Gava P, Hofer C, Loefler S, Gargiulo P, Mosole S, Zampieri S, Gobbo V, Ravara B, Piccione F, Marcante A, Baba A, Schils S, Pond A....There is something in our genome that dictates life expectancy and there is nothing that can be done to avoid this; indeed, there is not yet any record of a person who has cheated death. Our physical prowess can vacillate substantially in our lifetime according to our activity levels and nutritional status and we may fight aging, but we will inevitably lose. We have presented strong evidence that the atrophy which accompanies aging is to some extent caused by loss of innervation. We compared muscle biopsies of sedentary seniors to those of life long active seniors, and show that these groups i...
McGivney BA, McGettigan PA, Browne JA, Evans AC, Fonseca RG, Loftus BJ, Lohan A, MacHugh DE, Murphy BA, Katz LM, Hill EW.Digital gene expression profiling was used to characterize the assembly of genes expressed in equine skeletal muscle and to identify the subset of genes that were differentially expressed following a ten-month period of exercise training. The study cohort comprised seven Thoroughbred racehorses from a single training yard. Skeletal muscle biopsies were collected at rest from the gluteus medius at two time points: T(1) - untrained, (9 +/- 0.5 months old) and T(2) - trained (20 +/- 0.7 months old). Results: The most abundant mRNA transcripts in the muscle transcriptome were those involved in mus...
Tseng SH, Chen HC, Tam KW.To evaluate the literature on the efficacy of equine assisted activities and therapies (EAAT) on gross motor outcomes representing the ICF component of body functions and activity in children with cerebral palsy (CP). Methods: We conducted a systematic review and meta-analysis of randomized controlled trials and observational studies of hippotherapy (HPOT) and therapeutic horseback riding (TR) for children with spastic CP. Gross motor outcomes, assessed via muscle activity and muscle tone, gait, posture and Gross Motor Function Measures (GMFM) were evaluated. Results: Five TR studies and nine ...
Harris RC, Marlin DJ, Dunnett M, Snow DH, Hultman E.1. Muscle buffering capacity (beta m) and dipeptide content were measured in locomotory muscles of the Thoroughbred horse, Greyhound dog and Man. 2. Beta m and carnosine contents were highest in the horse. Anserine was only found in dog muscle. 3. The higher beta m in horse and dog muscle, compared with man, appears to be predominantly due to higher muscle contents of histidine containing dipeptides in these species.
Lindholm A, Piehl K.LINDHOLM, ARNE and KARIN PIEHL: Acta vet. scand. 1974, , 287–309. — Measurements of metabolites, electrolytes, water, RNA and protein concentrations, the activity of certain muscle enzymes (SDH and PFK) and muscle fibre composition were made on biopsy specimens from the gluteus medius muscle of 68 standardbred horses, ½ to 8 years old. The muscle fibres were classified in 3 major categories, slow twitch (ST), fast twitch and high oxidative (FTH) and fast twitch (FT) fibres. The percentage of FTH fibres was higher after the age of 4 years, averaging 54 %. ST fibres comprised 24 % and this...
Radtke CL, Nino-Fong R, Esparza Gonzalez BP, Stryhn H, McDï¿® LA.To characterize equine muscle tissue- and periosteal tissue-derived cells as mesenchymal stem cells (MSCs) and assess their proliferation capacity and osteogenic potential in comparison with bone marrow- and adipose tissue-derived MSCs. Methods: Tissues from 10 equine cadavers. Methods: Cells were isolated from left semitendinosus muscle tissue, periosteal tissue from the distomedial aspect of the right tibia, bone marrow aspirates from the fourth and fifth sternebrae, and adipose tissue from the left subcutaneous region. Mesenchymal stem cells were characterized on the basis of morphology, ad...
Wang ZW, Nara M, Wang YX, Kotlikoff MI.The effects of sulfhydryl reduction/oxidation on the gating of large-conductance, Ca(2+)-activated K+ (maxi-K) channels were examined in excised patches from tracheal myocytes. Channel activity was modified by sulfhydryl redox agents applied to the cytosolic surface, but not the extracellular surface, of membrane patches. Sulfhydryl reducing agents dithiothreitol, beta-mercaptoethanol, and GSH augmented, whereas sulfhydryl oxidizing agents diamide, thimerosal, and 2,2'-dithiodipyridine inhibited, channel activity in a concentration-dependent manner. Channel stimulation by reduction and inhibit...
Payne RC, Veenman P, Wilson AM.Muscles have two major roles in locomotion: to generate force and to absorb/generate power (do work). Economical force generation is achieved by short-fibred pennate muscle while the maximum power output of a muscle is architecture independent. In this study we tested the hypothesis that there is an anatomical and structural separation between the force-generating anti-gravity muscles and the propulsive (limb/trunk moving) muscles of the equine forelimb. Muscle mass and fascicle length measurements were made on the thoracic limb extrinsic muscles of six fresh horse cadavers. Physiological cros...
Stellingwerff T, Decombaz J, Harris RC, Boesch C.Interest into the effects of carnosine on cellular metabolism is rapidly expanding. The first study to demonstrate in humans that chronic β-alanine (BA) supplementation (~3-6 g BA/day for ~4 weeks) can result in significantly augmented muscle carnosine concentrations (>50%) was only recently published. BA supplementation is potentially poised for application beyond the niche exercise and performance-enhancement field and into other more clinical populations. When examining all BA supplementation studies that directly measure muscle carnosine (n=8), there is a significant linear correlation...
Westermann CM, Dorland L, Votion DM, de Sain-van der Velden MG, Wijnberg ID, Wanders RJ, Spliet WG, Testerink N, Berger R, Ruiter JP, van der Kolk JH.The aim of the current study was to assess lipid metabolism in horses with atypical myopathy. Urine samples from 10 cases were subjected to analysis of organic acids, glycine conjugates, and acylcarnitines revealing increased mean excretion of lactic acid, ethylmalonic acid, 2-methylsuccinic acid, butyrylglycine, (iso)valerylglycine, hexanoylglycine, free carnitine, C2-, C3-, C4-, C5-, C6-, C8-, C8:1-, C10:1-, and C10:2-carnitine as compared with 15 control horses (12 healthy and three with acute myopathy due to other causes). Analysis of plasma revealed similar results for these predominantly...
Baquero-Perez B, Kuchipudi SV, Nelli RK, Chang KC.Current methods of isolation of muscle satellite cells from different animal species are highly variable making inter-species comparisons problematic. This variation mainly stems from the use of different proteolytic enzymes to release the satellite cells from the muscle tissue (sometimes a single enzyme is used but often a combination of enzymes is preferred) and the different extracellular matrix proteins used to coat culture ware. In addition, isolation of satellite cells is frequently laborious and sometimes may require pre-plating of the cell preparation on uncoated flasks or Percoll cent...
Salazar P, Traub-Dargatz JL, Morley PS, Wilmot DD, Steffen DJ, Cunningham WE, Salman MD.To determine outcome of equids in the western United States with clinical signs of West Nile virus (WNV) infection and identify factors associated with risk of death in infected equids. Methods: Cross-sectional study. Methods: 484 equids in Nebraska and Colorado. Methods: Owners of 484 equids with laboratory-confirmed West Nile virus infection in Nebraska and Colorado were contacted by telephone, and a questionnaire was used to obtain information on signalment, management, clinical signs, date of disease onset, duration of disease, WNV vaccination status, and health status at the time of the i...
Bertoti DB.The purpose of this study was to measure postural changes in children with spastic cerebral palsy after participation in a therapeutic horseback riding program. Eleven children with moderate to severe spastic cerebral palsy, aged 2 years 4 months to 9 years 6 months, were selected for this study and underwent postural assessments according to a repeated-measures design. Assessment of posture was performed by a panel of three pediatric physical therapists, using a postural assessment scale designed by the author. A composite score for each test interval was calculated for each child, and a medi...
McGivney BA, Eivers SS, MacHugh DE, MacLeod JN, O'Gorman GM, Park SD, Katz LM, Hill EW.Selection for exercise-adapted phenotypes in the Thoroughbred racehorse has provided a valuable model system to understand molecular responses to exercise in skeletal muscle. Exercise stimulates immediate early molecular responses as well as delayed responses during recovery, resulting in a return to homeostasis and enabling long term adaptation. Global mRNA expression during the immediate-response period has not previously been reported in skeletal muscle following exercise in any species. Also, global gene expression changes in equine skeletal muscle following exercise have not been reported...
Byrd SK, McCutcheon LJ, Hodgson DR, Gollnick PD.This study examined the effects of acute high-intensity exercise on the rate and capacity of Ca2+ uptake and Ca2+-stimulated adenosinetriphosphatase (ATPase) activity of the sarcoplasmic reticulum and the reversibility of these effects. Thoroughbred horses were run at maximal O2 uptake on a high-speed treadmill until fatigued. Muscle temperatures and biopsy samples were collected at rest, immediately after exercise, and 30 and 60 min after exercise. Blood samples were collected at rest and 5 min after exercise. Muscle and blood (lactate concentration) were three- and fivefold greater than pre-...
Stull CL, Rodiek AV.Fifteen mature horses (mares, n = 6); geldings, n = 9) were used to assess the physiological responses of 24 h of transport in a commercial van under California summer conditions. The study was conducted on four consecutive days, and data were collected on d 1 and d 2 to obtain baseline values and to determine any diurnal variation in the individual measurements. Travel commenced on d 3 at 0800 for 24 h, with a total of 1,622 km traveled. Blood samples were collected at 0800, 1100, 1400, 2000, and 0200 each day. Horses were weighed and rectal temperatures recorded at 0800 each day and at 2000 ...
Rivero JL, Ruz A, MartÃ-Korff S, Estepa JC, Aguilera-Tejero E, Werkman J, Sobotta M, Lindner A.This study examined the effects of the intensity and duration of exercise on the nature and magnitude of training adaptations in muscle of adolescent (2-3 yr old) racehorses. Six thoroughbreds that had been pretrained for 2 mo performed six consecutive conditioning programs of varying lactate-guided intensities [velocities eliciting blood lactate concentrations of 2.5 mmol/l (v2.5) and 4 mmol/l (v4), respectively] and durations (5, 15, 25 min). Pre- and posttraining gluteus muscle biopsies were analyzed for myosin heavy chain content, fiber-type composition, fiber size, capillarization, and fi...
Liburt NR, Adams AA, Betancourt A, Horohov DW, McKeever KH.Studies have demonstrated increases in mRNA expression for inflammatory cytokines following exercise in horses and have suggested those markers of inflammation may play a role in delayed onset muscle soreness. However, measurement of mRNA expression in white blood cells is an indirect method. No studies to date have documented the cytokine response to exercise directly in muscle in horses. Objective: This study tested the hypothesis that exercise increases cytokine markers of inflammation in blood and muscle. Methods: Blood and muscle biopsies were obtained from 4 healthy, unfit Standardbred m...
