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.
Manley SV, Kelly AB, Hodgson D.Problems encountered during halothane anesthesia in 3 horses included increasing rectal temperature, muscle rigidity or movement during anesthesia, irregular breathing patterns, and difficulty in stabilizing blood pressure. One horse had prolonged muscle fasciculations and failure to relax after administration of succinylcholine in addition to halothane. That horse developed severe, bilateral myositis of the triceps, lumbar, and gluteal muscles. Problems encountered were similar to those caused by the disease known as malignant hyperthermia.
Davies JV, Gerring EL.Motility patterns in the equine small intestine were investigated in eight ponies. Muscular activity was assessed by means of extramural strain gauge transducers, bi-polar electrodes and in three of the animals, fitted with Thiry-Vella loops, the transit of fluid. Circular muscle contractions were preceded by spiking superimposed on the slow wave and fluid transit in the loops correlated with both these events.
Henckel P.The middle gluteal muscle of five, two-year-old untrained trotters was investigated by repeated needle biopsy sampling over a training period of six months. A second group of five, three-year-old untrained horses was included to examine the effect of growth. After the training period increases were found in the relative distribution of slow twitch (ST) fibres from 18 per cent to 25 per cent and fast twitch (FTa) fibres from 36 per cent to 45 per cent, and a decrease in FTb fibres from 46 per cent to 30 per cent. A proportionally equal reduction (approximately 18 per cent) in the cross sectiona...
McMiken DF.Although different physiological and behavioural attributes are needed for various types of equine competition, successful racing depends primarily on the animal's metabolic ability to convert chemical energy to mechanical energy--the function of muscle. Components of these energetic processes include the rate, efficiency and interaction of aerobic and anaerobic metabolism in muscle and the supply and utilisation of fuel. In anaerobic work like racing, fatigue processes may be largely regarded as a function of an intramuscular fuel (phosphogen) depletion, despite the fact that substrates are s...
Deldar A, Fregin FG, Bloom JC, Davanipour Z.The effects of strenuous exercise on serum electrolytes, blood metabolites, and serum enzymes were studied in a group of 13 horses participating in a 50-mile endurance ride. Blood samples were collected before, during, and at the end of the ride, as well as 1 hour and 16 hours after the completion of the ride. There were significant changes in these values when preride values were compared with those of samples taken at different sample-collection periods. Significant (P less than 0.001) decreases were observed in serum concentrations of chloride, potassium, and calcium. A significant increase...
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...
Muir WW, Sams RA, Huffman RH, Noonan JS.The cardiopulmonary, behavioral, and pharmacokinetic properties of diazepam were determined in horses. Heart rate, cardiac output, mean pulmonary artery, aortic and right atrial blood pressures, respiratory rate, and arterial pH and blood gas values did not change after IV diazepam (0.05, 0.1, 0.2, 0.4 mg/kg) administration. Increasing doses of diazepam resulted in signs of muscle weakness including fixed stance, muscle fasciculations of the head, neck, and thorax muscles, ataxia, and then recumbency. Dosages of diazepam exceeding 0.2 mg/kg produced mild sedation. Behavioral changes persisted ...
Argiroudis SA, Kent JE, Blackmore DJ.The isoenzymes of creatine kinase have been measured in serum and selected tissues from horses. The distribution followed that reported in other species in that the MM dimer of the isoenzyme was present in voluntary and non-voluntary muscle, thyroid, liver, spleen, lung and intestine. The BB dimer of the isoenzyme was predominant in brain, pancreas, kidney, intestine, lung, spleen, liver and thyroid. In contrast, in 4 hearts examined less than 1.5 per cent of the total creatine kinase activity was attributable to the MB form of the isoenzyme. The MB isoenzyme was, however, present in intestine...
Jones S, Blackmore DJ.The distribution of the isoenzymes of aspartate aminotransferase (AST, E.C. 2.6.1.1.) in equine tissues has been studied to ascertain whether the organ of origin may be identified when the total AST activity of serum is raised. Most tissues contain 3 isoenzymes of cytoplasmic origin (cAST) with isoelectric points of 5.6, 5.7 and 5.9, and one isoenzyme of mitochondrial (mAST) origin with an isoelectric point of 9. Serum from horses with azoturia contained an additional cytoplasmic subform with an isoelectric point of 5.8. This form could not be generated by ageing, freezing and thawing or bindi...
Nimmo MA, Snow DH.To ascertain the effects of sprint and endurance exercise on the time course of skeletal muscle mitochondrial changes, an ultrastructural study was conducted on four Thoroughbred horses. Skeletal muscle biopsies were taken at various intervals during and after the exercise. Transient mitochondrial alterations of varying degrees were observed following both types of exercise and were considered to be related to the development of fatigue. The degree of distortion of mitochondrial structure is considered not to represent the in vivo condition but the state of responsiveness to the fixation mediu...
Berti A, Liguri G, Stefani M, Nassi P, Ramponi G.Horse muscle acylphosphatase antibodies were obtained by immunizing rabbits with the highly purified antigen cross-linked with glutaraldehyde. Specific antibodies were purified from the immunoglobulin fraction by affinity chromatography using a matrix coupled with the pure antigen as immunoadsorbent. The purified antibodies were partially characterized by immunodiffusion and immunoprecipitin techniques. These antibodies could be used to study aspects of the muscle acylphosphatase structure, localization and other biological properties.
Ford EJ, Adam SE.In the horse, 5'-nucleotidase (5'-NT) activity is found mainly in homogenates of lung, kidney, small intestine, mammary gland, liver and pancreas. Lower activities are present in brain and muscle. Activity can be demonstrated histochemically in the glomeruli and tubules of the kidney, in the sinusoidal borders of the hepatocytes and the bile duct epithelium as well as in the blood vessels of all organs. There is no significant difference between the 5'-NT activity in serum and plasma of normal horses and of horses suffering from a range of orthopaedic conditions. Previous findings that gamma g...
Waldron-Mease E, Klein LV, Rosenberg H, Leitch M.Malignant hyperthermia developed in a 4-year-old Thoroughbred horse following 3 hours and 15 minutes of halothane anesthesia, with supplementary succinylcholine. Clinical signs included fever, sweating, hyperventilation, tachycardia, and decreased blood pressure followed by a rapid increase in blood pressure. Biochemical aberrations included hypocalcemia, hyperkalemia, hyperphosphatemia, myoglobinuria, and high creatine phosphokinase and ornithine carbamyl transferase activities. Treatment consisted initially of surface cooling with cold water, alcohol and ice, IV administration of cooled bala...
Hardy GW, Darbre A, Merrett M.3-Phosphoglycerate kinase was isolated from horse muscle and subjected to the action of cyanogen bromide. The resulting peptides were separated using gel filtration combined with either ion exchange chromatography on phosphocellulose in 6 M urea or high voltage paper electrophoresis. The sequence of the largest peptide, CB5, has been determined by a combination of automated and manual Edman degradation carried out on the intact peptide and derivatives obtained by proteolytic digestion. The isolation of two peptides derived from CB5 by cleavage of the bond between Asp109 and Pro110 facilitated ...
Klein L, Hopkins J.4-Aminopyridine was administered in incremental IV doses to healthy horses to evaluate cardiorespiratory and behavioral effects. Doses of 100 micrograms/kg produced apparent sensory discomfort, manifested by wiggling or curling of the lips and tongue, arching or stretching the neck, snorting, squealing, and coughing. At cumulative dosages of 300 to 500 micrograms/kg, muscle tremors, a stilted gait, and signs of excitement occurred. Once signs of excitement occurred, additional administration of 4-aminopyridine resulted in prolonged excitement consisting of severe muscle tremors and exaggerated...
Weaver BM, Webb AI.The halothane muscle/gas partition coefficients at 37 degrees C for 26 samples of eight different muscles from four horses were found to depend significantly on the fat content of the muscle sample with a regression coefficient of 1.913 (SEM 0.109) per per cent ether-extractable fat content. The blood/gas partition coefficients in 24 horses showed a significant dependence on plasma triglyceride concentration (regression coefficient 0.00084 (SEM 0.00033) per mg dl-1), an insignificant positive dependence on plasma free and total cholesterol concentration and, in a multiple regression analysis, ...
Snow DH, Baxter P, Rose RJ.An investigation into fibre composition and glycogen depletion pattern within the middle gluteal of 16 horses participating in an 80 km endurance ride was carried out. Although the proportion of slow twitch high oxidative (ST) fibres in the horses varied between 7 and 38 per cent, it was found that the horses with the highest proportion of these fibres usually had the best performance records. The cross-sectional area of the fast twitch low oxidative (FT) fibres was greatest, with the ST and fast twitch high oxidative (FTH) being similar in size. Most marked histological evidence of glycogen d...
Camici G, Manao G, Cappugi G, Ramponi G.We have predicted the secondary structure of horse muscle acylphosphatase by the statistical method of Chou and Fasman. In addition, we have studied the circular dichroism spectra of the enzyme, obtaining values for comparison to the predicted results. Discrepancies were found for the alpha-helix content estimated by the two methods.
Erber M, Geisel O.The prevalence of Sarcocystis spp. in horses was investigated in a survey at the Munich abattoir during 1978/79. Muscle specimens (oesophagus, diaphragm, sublingual muscle, myocardium) were examined using tryptic digestion. Out of 200 horses 31 (15.5%) were found to be carriers of sarcocysts. No parasites were found in the myocardium. In three animals sarcocysts could be isolated and differentiated in fresh preparations. Cysts with 5 to 11 microns by less than 0.5 microns hairlike, unstable protrusions were classified as Sarcocystis equicanis, whereas those with 2.5 to 4.5 microns by 0.8 to 1....
Hambleton PL, Slade LM, Hamar DW, Kienholz EW, Lewis LD.Four isocaloric diets containing 4, 8, 12 and 16% dietary fat (as soybean oil) were fed to four horses at four intervals according to a Latin square design. After 3 weeks of conditioning at each interval, diet effects were evaluated by trotting all horses at 3.2 m/sec for 6 hours. Pre- and posttrotting responses were measured in muscle and liver glycogen, serum long-chain fatty acids, serum electrolytes, serum enzymes, serum cholesterol, plasma glucose, packed cell volume and hemoglobin. Dietary fat was highly correlated with exercise-induced plasma glucose changes and with cholesterol concent...
Lindsay WA, McDonell W, Bignell W.Intracompartmental muscle pressures were recorded from the right and left forelimbs (extensor carpi radialis, triceps brachii) of healthy horses maintained in left lateral recumbency while under deep halothane anesthesia for 180 to 240 minutes. Cardiac output, blood pressure, blood gases, and acid-base status were monitored throughout the anesthesia, and electrolyte levels (Ca2+, P+, K+, Cl-, Na+) and enzyme activities (aspartate aminotransferase (AST), creatine phosphokinase (CPK), and blood lactate) were monitored for 7 days. Postanesthetic forelimb lameness was produced in 5 of the 6 horses...
Chacon-Arellano JT, Woolley DM.Smooth muscle cells are present in the tunica albuginea testis of the horse, pig and sheep. typical fusiform muscle cells constitute a distinct layer up to 0.3 micrometer thick in the horse; there are fewer muscle cells, mainly of the branched form, in the pig; whereas in the sheep the muscle component is least well developed, with some cells intermediate in form between smooth muscle cells and fibroblasts (myofibroblasts). Attention is drawn to the continuity of this capsular muscle with the smooth muscle associated with the vasculature of the spermatic cord in the horse. This association sug...
Wolschrijn CF, Smit IH, Schouten J, Moller Te NCR.Facial expressions are important in pain recognition in horses, but current observation-based pain scales remain subjective. A promising technique to quantitatively measure subtle changes in expression patterns, including changes invisible to the human eye, is surface electromyography (sEMG). To achieve high-quality and reliable sEMG signals, unilateral placement of bipolar electrodes is required in relation to the motor endplates (MEP). We aimed to localize the nerve entry points (NEPs; where the nerve branch first pierced the muscle belly) and the direction of the terminal nerve endings to e...
Takahashi K, Mukai K, Ebisuda Y, Sugiyama F, Yoshida T, Hatta H, Kitaoka Y.Evidence suggests that positive pacing strategy improves exercise performance and fatigue tolerance in athletic events lasting 1-5 min. This study investigated muscle metabolic responses to positive and negative pacing strategies in Thoroughbred horses. Eight Thoroughbred horses performed 2 min treadmill running using positive (1 min at 110% maximal O uptake [V̇Omax], followed by 1 min at 90% V̇Omax) and negative (1 min at 90% V̇Omax, followed by 1 min at 110% V̇Omax) pacing strategies. The arterial-mixed venous O difference did not significantly differ between the two strategies. Pl...
Lashkari S, Beblein C, Christensen JW, Jensen SK.High-starch diets may affect equine hindgut microbiota and increase blood glucose levels, which may cause unwanted physiological changes, but may also elicit behavioural changes such as increased fear reactions. The purpose of the current study was to feed a high starch (300) and low fat (43; HS_LF) or a low starch (60) and high fat (85; LS_HF, g/kg of DM) concentrate within the available commercial range and investigate how muscle endurance and fear reactions of horses respond to different diets. Twenty Danish Warmblood stallions (4 years) were randomly allocated to two treatments: LS_HF (nâ€...
Ding W, Gong W, Liu H, Hu H, Shi L, Ren X, Cao Y, Zhang A, Shi X, Li Z, Bou T, Dugarjaviin M, Bai D.The growth and development of myofibers, as the fundamental units comprising muscle tissue, and their composition type are indeed among the most crucial factors influencing skeletal muscle types. Muscle fiber adaptation is closely associated with alterations in physiological conditions. Muscle fiber types undergo dynamic changes in fetus and adult horses. Our aim is to investigate the mechanisms influencing the differences in muscle fiber types between fetal and adult stages of Mongolian horses. The study investigated the distribution of muscle fiber types within longissimus dorsi muscle of fe...
Graham-Thiers PM, Bowen LK.Twelve horses weighing 570 ± 35 kg were split into two groups (standard protein, STD, and balanced protein, BAL) to evaluate the effect of balanced vs. unbalanced protein on muscle mass. Groups were fed grass hay and a 12% CP feed (one formulated for balanced protein). Horses were out of work for 14 wk prior and participated in 1 to 2 h of light-to-moderate exercise 5 d/wk for 12 wk. A 4-d total urine and feces collection period was conducted at the start and end of the study. Urine and feces samples were analyzed for nitrogen (N) to calculate N balance. Muscle mass status was evalua...
Bielińska K, Butkiewicz AF, Ziemak H, Zdun M.Due to the growing interest among veterinarians and the increasing market demands, the development of equine cardiology is necessary. Currently, veterinary medicine for companion animals needs to catch up to human medicine-equine medicine included. A common condition in older horses is aortic valve regurgitation resulting from fibrosis, while its more severe form occurs in younger horses or develops due to a bacterial infection. Mitral valve regurgitation, especially dangerous due to the possibility of sudden death, has a better prognosis if the horse has valve prolapse. Tricuspid valve regurg...
Pereira AT, Pozzobon R, Dos Anjos BL, Chaves LT, Smilgys ÉC, Thoma AJS, Lunkes VL, de Oliveira JS, de Andrade CM, Soares JCM.Criollo breed is quite popular in Brazil, mainly in the Southern Region, and the long loop rodeo is one of the main sports modality adapted to this breed. The purpose of this study was to assess changes in the muscle and oxidative functions caused by exercises practiced in this sports modality. Data such as exercising frequency, covered distance, mean duration time and number of runs, and blood samples at the following times: before the tournament, on the final day of the event, and 18-24 h after the end of the tournament were collected. Were assessed lactate and the enzymes aspartate aminotra...
Dubey JP, Gupta A, Calero-Bernal R, de Araujo LS, GarcÃa-Gil ML, Battle J, Ankarah A, Van Why K, Brown JD, Rosenthal BM.The protozoan Sarcocystis neurona can cause severe disease in horses, marine mammals, and several other animal species in North America. The Virginia opossum (Didelphis virginiana) is its definitive host, and the raccoon (Procyon lotor) has been considered its primary intermediate host in the USA. Although canids have not previously been identified as important intermediate hosts for this parasite, we here report several natural cases in the gray fox (Urocyon cinereoargenteus). We identified muscular infections in 11 (23.9Â %) of 46Â gray foxes from Pennsylvania, USA. In hematoxylin and eosin ...
Davis MS, Bayly WM, Hansen CM, Barrett MR, Blake CA.The intracellular environment of skeletal muscle can develop pronounced hyperthermia and acidosis during strenuous exercise, and these alterations in the typical intracellular conditions have been shown to alter mitochondrial respiration. However, the impact of these conditions on ATP synthesis is poorly understood. We used Thoroughbred racehorses to test the hypothesis that both hyperthermia and acidosis decrease the rate of ATP synthesis, but that athletic conditioning mitigates this loss of phosphorylation capacity. Isolated mitochondria were harvested from skeletal muscle before and after ...
Frers F, Delarocque J, Feige K, Huber K, Warnken T.The underlying molecular mechanisms leading to insulin dysregulation are poorly understood in horses. Therefore, this study aimed to determine if insulin dysregulation is associated with an altered basal expression and extent of phosphorylation of key proteins of the insulin signaling cascade in liver (LT), muscle (MT), and subcutaneous adipose tissue (AT) under basal and stimulated conditions. Twelve Icelandic horses were subjected (1) to an oral glucose (Gluc PO) challenge and (2) to an intravenous (Ins IV) insulin challenge in a crossover study. Biopsies of LT, MT, and AT were taken in vivo...
Hepworth-Warren KL, Goldsmith D, Tsoi M, Gerras A, Noll C, Pinn-Woodcock T, Moreira A, Penttila K, Ballou ME, Dembek KA, Valberg SJ.To describe the clinical findings, outcomes, and muscle histopathology in warmblood horses that developed severe rhabdomyolysis in the perianesthetic period despite remaining stable while under general anesthesia. Methods: 7 warmblood horses, 6 geldings and 1 mare, with a median age of 9 years (range, 4 to 18 years) and median weight of 615 kg (range, 550 to 703 kg). Records from the Valberg Neuromuscular Diagnostic Laboratory and Michigan State University were reviewed (2016 to 2023) to identify warmbloods with postanesthetic myopathy (PAM). Methods: Warmblood horses with no history of myopat...
Carvalho Serena G, Marchezan Piva M, Viezzer Bianchi M, Fernandes da Fonseca HC, Chitolina Pupin R, Martins Basso R, Secorun Borges A....In horses, systemic calcinosis is a rare syndrome characterised by muscle lesion associated with the mineralisation of large muscle groups or other organs, in the absence of an alternative cause for the calcification, such as toxic, enzootic or metabolic. Molecular and histopathological aspects of the disease are still poorly elucidated. Objective: To describe the epidemiological, pathological and molecular aspects of systemic calcinosis in a convenience sample of six horses submitted to necropsy in the Southern and Midwestern regions of Brazil. Methods: Retrospective exploratory study. Method...
King MR, Colla S.Rehabilitation following muscle injury is critical in restoring the equine athlete to full function. Rehabilitation protocols should be tailored to each patient's global functional assessment, taking into account sports-specific demands, goals for return-to-performance, and overall prognosis. Rehabilitation protocols are often designed to modulate pain, enhance repair, improve proprioception, increase flexibility, restore muscle strength, joint range-of-motion, and neuromotor control. This article will review mechanisms of muscle injury, various physical modalities commonly employed in the reh...
Myćka G, Ropka-Molik K, Cywińska A, Stefaniuk-Szmukier M.Among numerous genes that have been a focus of equine genetic research, the (Klotho) and (Alpha-actinin-3) genes stand out due to their significant roles in muscle function and overall health, as well as performance ability. Previous studies on Arabian horses and other mammalians have shown that both and occur in different isoforms that seem to have different roles in metabolism. The main purpose of this present study was to describe different isoforms (, , , , , ) expression levels affected by the endurance effort in Arabian horses. Methods: Blood samples were taken from a group of = 10 ...
McGowan C.Traumatic muscle injuries are likely to be frequent in athletic horses yet are often overlooked. These injuries usually involve internal (intrinsic) trauma, and particularly occur in athletic horses exercising at higher intensities, at unaccustomed workloads, or performing work requiring sudden acceleration, deceleration, and/or direction changes. These injuries can present with signs ranging from acute pain and lameness in a localized region to unexplained elevations of muscle enzymes on routine blood tests with or without poor performance. They include exercise-induced muscle damage such as ...
King MR, Colla S.Successful rehabilitation of muscle injury requires a comprehensive understanding of the injury process, healing phases, and resources to be employed. The initial phase is characterized by acute inflammatory signs, followed by the regenerative and remodeling phases. Therapeutic exercises can be utilized in all 3 phases, progressing from isometric exercises to aquatic therapies. The classification and phase of injury and the individual response to the applied therapies will guide the progression of the therapeutic exercises through the rehabilitation program.
Durward-Akhurst SA, Valberg SJ.Several inflammatory myopathies have an infectious or immune-mediated basis in the horse. Myosin heavy chain myopathy is caused by a codominant missense variant in MYH1 and has 3 clinical presentations: immune-mediated myositis, calciphylaxis, and nonexertional rhabdomyolysis in Quarter Horse-related breeds. An infarctive form of purpura hemorrhagica affects numerous breeds, presenting with focal firm, painful muscle swelling, and subsequent infarction of multiple tissues. While Streptococcus equi equi is often the inciting cause, anaplasmosis, sarcocystis, piroplasmosis, viruses, and vaccines...
Valberg SJ, Williams ZJ.Myofibrillar myopathy (MFM) is characterized by segmental disarray of myofibrils and ectopic accumulation of a protein called desmin. Previously thought to be a glycogen storage disease, MFM is now recognized as a stand-alone myopathy. Endurance Arabians with MFM usually present with exertional rhabdomyolysis (MFM-ER) at the end of races, elevated serum muscle enzymes, and myoglobinuria. Warmblood horses with MFM (MFM-WB) usually present with pain-associated behaviors such as exercise intolerance, reluctance to engage hind quarter muscles, shifting lameness and normal serum muscle enzymes. Bot...
Barshick MR, Ely KM, Mogge KC, Chance LM, Johnson SE.Methylsulfonylmethane (MSM) is a sulfur-containing molecule with reported anti-inflammatory and antioxidant activities. Exercise causes the formation of free radicals and stimulates inflammatory gene expression in leukocytes and skeletal muscle. The hypothesis that dietary supplementation with MSM alters the exercise-mediated inflammatory and oxidant response was assessed in unfit adult thoroughbred geldings. Ten geldings (6.7 ± 1.6 yr) were assigned to a diet supplemented without (CON, = 5) or with 21 g of MSM ( = 5) for 30 days. Following the supplementation period, horses performed a stan...
Kodaira K, Kakizaki M, Nagata SI, Ode H, Okano A, Tamura N, Mizobe F, Matsuda Y, Kurimoto S, Aida H.To investigate the pharmacodynamics and pharmacokinetics of rocuronium administered by bolus injection to sevoflurane-anesthetized horses. Methods: Prospective, experimental, crossover study. Methods: Five healthy adult Thoroughbred horses (body mass 368-470 kg, three females and two males). Methods: Each horse was anesthetized twice with sevoflurane and assigned to be administered rocuronium bromide intravenously: 0.2 mg kg (R02) or 0.4 mg kg (R04). There was a minimum 2 week washout period between experiments. During anesthesia, the peroneal nerve was stimulated (train-of-four) and neuromusc...
Mehrazin H, Sakha M, Safi S.Due to their high specificity and exclusive cardiac myocyte sensitivity, cardiac troponins T and I (cTnT, cTnI) are currently regarded as ideal biomarkers to identify cardiomyocyte damage, myocardial injury, myocardial infarction, and chronic heart failure. In fact, cTnI is considered the most reliable biomarker for diagnosing heart-related issues. This study aimed to investigate the effects of age, gender, and exercise training on serum cTnI levels and various parameters related to the cardiovascular capacity of Caspian horses. For this purpose, 50 adult Caspian horses over 3 years old, both ...
Loos CMM, Urschel KL.Insulin dysregulation (ID) is a common metabolic disorder in horses, characterized by hyperinsulinemia and/or peripheral insulin resistance. The critical role of hyperinsulinemia in endocrinopathic laminitis has driven research into the insulinotropic effects of dietary nutrients and the reciprocal impact of ID on nutrient metabolism. The relationship between ID and carbohydrate metabolism has been extensively studied; however, the effects of ID on protein metabolism in horses remain largely unexplored. This review begins with an overview of the importance of insulin in the regulation of muscl...
Al-Khaldi KO, Al-Ruzaiqi KH, Babji AS, Lim SJ, Sadiq MB, Yimer N.Exercise-induced oxidative stress and inflammation adversely affect the health and performance of athletic horses. This study aimed to evaluate the safety of edible bird's nest (EBN) supplementation and its potential anti-inflammatory and immunomodulatory effects in Arabian race stallions during exercise. Key objectives included assessing EBN's impact on hepatic and renal function, hematological profiles, and sialic acid (SA) levels. Unassigned: Two experiments were conducted on 18 Arabian stallions. In Experiment 1, six healthy stallions were divided into control (n = 2) and EBN-supplemented ...
Nourinezhad J, Abdi A, Moarabi A, Hanafi MG, Fatahian Dehkordi RA, Tomańska A.Visualizing the major salivary glands (MSGs) in domestic mammals using plain radiology and identifying damaged their structures is impossible. To accurately display MSGs, the knowledge of normal sectional imaging anatomy is essential for veterinarians, aiding them significantly in identifying the exact relations and position of MSGs; however, no reports on the MSGs sectional imaging anatomy in this species have been made. Objective: This study aimed to evaluate computed tomography (CT), magnetic resonance imaging (MRI) and gross sections of MSGs. Methods: Seven healthy adult donkeys were used ...
Hansen S, Hopster-Iversen C, Berg L, Fjeldborg J, Massey C, Piercy RJ, Carstensen H.Exertional myopathies are recognised as a cause of poor performance in equines. In Icelandic horses presenting reduced performance and/or multi-limb lameness, no specific myopathy has been identified. Objective: To characterise the clinical presentation and histopathological findings in muscle biopsy samples from Icelandic horses demonstrating poor performance. Methods: Case series. Methods: Phenotypic characteristics, clinical examination and diagnoses of 17 Icelandic horses were studied. All horses had a resting serum creatine kinase (CK) and aspartate transaminase activities measured, and C...
Shokry M, Ali LB, El-Sharkawy M.Showjumping athletic horses are frequently affected by back pain, which in turn influences their performance and equestrian activities. Unassigned: The aim of the present study was to determine the etiological factors predisposing to back problems in show jumping horses and how to diagnose, and manage them. Unassigned: A total of 75 cases (45 geldings and 30 mares, aged between 8 and 23 years and weighing 420-550 Kg) with histories suggestive of back problems and low competitive ability as show jumping were used in this study. The evaluation of data was based on the inputs of case history, cli...
Aleman M, McCue M, Bellone RR.Fatal anesthesia-induced malignant hyperthermia (MH) and rhabdomyolysis with hyperthermia documented in Quarter Horses (QH) breeds are caused by a missense variant in the ryanodine receptor 1 gene (RYR1: XP_023505430.1.:p.(R2454G), designated as MH). The reported cases to date have all been heterozygous, and the allele frequency is suspected to be low. Objective: To determine an accurate estimate of MH allele frequency in multiple horse breeds and investigate whether homozygous animals exist in the population. Methods: In total, 159 227 horses from 16 breeds who were either submitted for cli...
Connysson M, Jansson A.It is generally accepted that plasma muscle enzyme activity of creatine kinase (CK) and aspartate aminotransferase (AST) may increase in racehorses after exercise and racing, indicating muscle fibre damage and/or increased leakage from muscle fibres. However, other studies suggest that starch intake might influence plasma muscle enzyme activity reported postexercise. This study aimed to evaluate the effect of different starch allowances on plasma muscle enzyme activity in Standardbred trotters in professional training. Seventy-six horses from five professional trainers were sampled pre- and po...
Ding W, Gong W, Bou T, Shi L, Lin Y, Shi X, Li Z, Wu H, Dugarjaviin M, Bai D.Copy number variation (CNV) is an important source of genetic variation. However, studies utilizing whole-genome sequencing to investigate CNVs in horse populations and their effects on traits remain relatively limited. This study aims to address the lack of research on the impact of copy number variation (CNV) on racing performance in horse populations, providing new insights for locally bred racing breeds. We analyzed 60 offspring derived from the crossbreeding of Thoroughbred horses and Xilingol horses. These horses were temporarily named "Grassland-Thoroughbred" and were divided into two g...
Domino M, Borowska M, Stefanik E, Domańska-Kruppa N, Skibniewski M, Turek B.In equine surface electromyography (sEMG), challenges related to the reliability and interpretability of data arise, among other factors, from methodological differences, including signal processing and analysis. The aim of this study is to demonstrate the filtering-induced changes in basic signal features in relation to the balance between signal loss and noise attenuation. Raw sEMG signals were collected from the quadriceps muscle of six horses during walk, trot, and canter and then filtered using eight filtering methods with varying cut-off frequencies (low-pass at 10 Hz, high-pass at 20 Hz...
