Biomarkers in horses are measurable indicators of biological processes, states, or conditions that can be used to assess health and disease. These biomarkers can be identified in various biological samples such as blood, urine, or tissue. They provide valuable information for diagnosing diseases, monitoring health status, and evaluating treatment responses in equine medicine. Common biomarkers in horses include enzymes, hormones, and metabolites, which may change in response to physiological or pathological conditions. This page compiles peer-reviewed research studies and scholarly articles that explore the identification, quantification, and application of biomarkers in equine health and disease management.
de Grauw JC, van de Lest CH, van Weeren R, Brommer H, Brama PA.Joint pain is one of the most common causes of lameness in the horse but its pathogenesis is poorly understood. Objective: To investigate which synovial fluid markers may be related to the presence of clinically detectable joint pain in the horse. Methods: Concentrations of structural (CPII, C2C, GAG) and inflammatory markers (PGE2, LTB4, CysLTs, bradykinin and substance P) were measured in fetlock joint fluid from 22 horses in which lameness was localised to the fetlock region by perineural anaesthesia. Levels of these markers were then compared in horses that responded (n = 15) to those that...
de Grauw JC, Brama PA, Wiemer P, Brommer H, van de Lest CH, van Weeren PR.To assess whether reported alterations in metabolism of cartilage matrix in young (0 to 24 months old) horses with osteochondritis dissecans (OCD) may also be found in older (24 to 48 months old) horses with clinical signs of OCD and to investigate the role of eicosanoids in initiating these clinical signs. Methods: Synovial fluid was collected from 38 tarsocrural joints of 24 warmblood horses with (22 joints of 16 horses) or without (16 joints of 8 horses) clinical signs and a radiographic diagnosis of OCD of the distal intermediate ridge of the tibia. Methods: Turnover of type II collagen wa...
Gangl M, Serteyn D, Lejeune JP, Schneider N, Grulke S, Peters F, Vila T, Deby-Dupont G, Deberg M, Henrotin Y.Markers of cartilage breakdown enable studying the degradation of cartilage matrix in equine joint pathologies. This study was designed to determine the levels of Coll2-1, a peptide of the triple helix of type II collagen, and Coll2-1NO(2), its nitrated form in the plasma of healthy horses (controls; n=37) and horses suffering from osteochondrosis (n=34). Clinical and arthroscopic scores were attributed reflecting the severity of lesions and were related to the plasma levels of Coll2-1 and Coll2-1NO(2). The median of Coll2-1 was significantly higher in the control group, whereas the mean of Co...
Vandenplas ML, Moore JN, Barton MH, Roussel AJ, Cohen ND.To determine concentrations of 2 acute-phase proteins (serum amyloid A [SAA] and lipopolysaccharide-binding protein [LBP]) in serum samples obtained from horses with colic and identify relationships among these acute-phase proteins and clinical data. Methods: 765 horses with naturally developing gastrointestinal tract diseases characterized by colic (ie, clinical signs indicative of abdominal pain) and 79 healthy control horses; all horses were examined at 2 university teaching hospitals. Methods: Serum concentrations of SAA and LBP were determined by immunoturbidometric and dot-blot assays, r...
Wyse CA, Skeldon K, Hotchkiss JW, Gibson G, Yam PS, Christley RM, Preston T, Cumming DR, Padgett M, Cooper JC, Love S.The aim of this study was to assess the effects of changes to the stable environment on exhaled markers of respiratory inflammation in six horses with clinical histories of recurrent airway obstruction. The horses were maintained for two weeks under conventional stable management (straw bedding and hay) and for two weeks on a reduced-dust regimen (paper bedding and ensiled grass), in a crossover study design. Exhaled ethane and carbon monoxide (CO) and exhaled breath condensate hydrogen peroxide (H(2)O(2)) were measured every three days under each regimen. The presence of clinical signs of air...
Simonen-Jokinen T, Pirie RS, McGorum BC, Maisi P.Airway matrix metalloproteinases (MMPs) increase following inhalation of organic dust. The relative contribution of dust components to this elevation is unknown. Objective: To identify components of organic dust responsible for elevated MMP levels in equine airways. Methods: Bronchoalveolar lavage (BALF) from 7 heaves-susceptible horses, collected 6 h following inhalation challenges with saline, 2 different hay dust suspensions (HDS-1 and -2) and soluble and particulate fractions of HDS-1, were analysed for MMP-2 and -9 using SDS-page gelatin zymography. Results: HDS-1 challenge increased BALF...
Slack JA, McGuirk SM, Erb HN, Lien L, Coombs D, Semrad SD, Riseberg A, Marques F, Darien B, Fallon L, Burns P, Murakami MA, Apple FS, Peek SF.The cardiac biomarkers cardiac troponin T (cTnT) and I (cTnI) and the cardiac isoenzyme of creatine kinase (CKMB) are used extensively in human medicine to diagnose and provide valuable prognostic information in patients with ischemic, traumatic, and septic myocardial injury. We designed a study to establish normal values for these markers in healthy, neonatal foals and to compare them with values obtained from septic neonates in a referral hospital population. The 25th, 50th, 75th, and 95th percentiles for cTnI and CKMB in the healthy-foal population were 0.08, 0.14, 0.25, 0.49 ng/mL and 1.4,...
Wyse C, Cathcart A, Sutherland R, Ward S, McMillan L, Gibson G, Padgett M, Skeldon K.Exercise-induced oxidative stress (EIOS) refers to a condition where the balance of free radical production and antioxidant systems is disturbed during exercise in favour of pro-oxidant free radicals. Breath ethane is a product of free radical-mediated oxidation of cell membrane lipids and is considered to be a reliable marker of oxidative stress. The heatshock protein, haem oxygenase, is induced by oxidative stress and degrades haemoglobin to bilirubin, with concurrent production of carbon monoxide (CO). The aim of this study was to investigate the effect of maximal exercise on exhaled ethane...
Knopp U, Christmann F, Reusche E, Sepehrnia A.Numerous types of materials have been evaluated over the past decades in the quest for the ideal dural replacement, but no product fully meets all the applicable criteria. This paper presents the long-term results of an animal trial of a collagen biomatrix (TISSUDURA, Baxter AG, Vienna/Austria) for the repair and regeneration of dural defects. This product provides a matrix with a special layer structure and consists of pure naturally cross-linked collagen of equine origin. The comparable material is Tutoplast Dura, a human cadaveric-derived dural graft preserved in a multiple stage chemical p...
van den Boom R, van de Lest CH, Bull S, Brama RA, van Weeren PR, Barneveld A.The importance of osteoarthritis (OA) in the horse and the difficulty in its early diagnosis have led to a search for potential biomarkers of joint disease. If the levels of such markers are to be interpreted accurately, clinicians and researchers need to know whether they are influenced by environmental factors and/or interventions such as exercise and repeated arthrocentesis. Objective: To investigate the influence of repeated arthrocentesis and exercise on nitric oxide (NO), prostaglandin E2 (PGE2) and glycosaminoglycan (GAG) concentrations in synovial fluid (SF) from normal equine joints. ...
Pollock PJ, Prendergast M, Schumacher J, Bellenger CR.The serum concentrations of serum amyloid A, haptoglobin and fibrinogen were measured in a group of horses before and at intervals after elective and non-elective surgery, and in a control group of normal horses. There was a significant, rapid and repeatable increase in the concentration of serum amyloid A in response to both elective and non-elective surgery. In the control horses its serum concentration was within the normal range, from 0 to 0.2 microg/ml. Twenty-four hours after elective surgery its mean peak concentration was 16.4 microg/ml, and after non-elective surgery it was 27.3 micro...
Carstanjen B, Amory H, Sulon J, Hars O, Remy B, Langlois P, Lepage OM.Bone responds to exercise with changes in bone (re-)modelling, which might be monitored non-invasively with biochemical bone markers. The aim of this study was to evaluate the influence of exercise on serum osteocalcin and serum carboxy-terminal cross-linked telopeptide of type I collagen generated by matrix metalloproteinases (CTX-MMP) concentration in young racehorses. Seventy-one 2 to 4-year-old Thoroughbreds were included in this prospective infield study. Blood sampling was performed six times (i.e. six sampling cycles) during a 9-month period. Serum samples were analysed with commercial ...
Simonen-Jokinen T, Pirie RS, McGorum B, Maisi P.Airway matrix metalloproteinases (MMPs) increase after endotoxin (LPS) exposure, but there are no reports describing dose-dependent increases or activation following exposure. Objective: To study matrix metalloproteinase-9 (MMP-9) and -2 (MMP-2) responses in bronchoalveolar lavage fluid (BALF) from heaves-susceptible and control horses following inhalation of hay dust suspension (HDS), LPS and Aspergillus fumigatus extract (AFE). Methods: Heaves-susceptible (n = 7) and control (n = 6) horses received inhalation challenges with 3 different doses of HDS and LPS. Heaves-susceptible horses (n = 6)...
Tandon R, Lyons ET, Tolliver SC, Kaplan RM.Cyathostomins are among the most important intestinal nematodes of horses, yet, the literature on the molecular genetics of these worms is scarce. In this study, the technique of amplified fragment length polymorphism (AFLP) was applied to study the genetic diversity as well as to determine the effect of moxidectin selection on the population genetic diversity for Cylicocyclus nassatus, one of the most common cyathostomin species. Genomic DNAs from 30 individual male worms were used from each of two populations: an avermectin-milbemycin (AM)-naive population (Population-S) and a population der...
van der Harst MR, Bull S, Laffont CM, Klein WR.The aminoglycoside gentamicin is often used in equine practice. Despite its clinical use, concerns remain regarding the potential toxic side-effects, such as nephrotoxicity, in equine patients, particularly after repeated dosing. The aim of the study was to investigate first in vitro the mechanisms contributing to the renal toxicity of gentamicin and to identify sensitive biomarkers indicating proximal tubule damage. To this end, the kidney-derived cell lines LLC-PKI and MDCK were treated with gentamicin at different concentrations. Toxicity was assessed by measuring the release of gamma-gluta...
Lee SJ, Lee KG.The inhibitory effect of aroma extracts isolated from dried soybeans, mung beans, kidney beans, and azuki beans on malonaldehyde (MA) formation from horse blood plasma oxidized with Fenton's reagent was determined by gas chromatography (GC) coupled with nitrogen-phosphorus detector (NPD). Aroma chemicals such as maltol, eugenol, benzyl alcohol, 1-octen-3-ol, butyrolactone, and 1-methyl-2-pyrrolidone, found in the aroma extracts of beans, were also examined for their inhibitory effect on the same system. Among the four aroma extracts tested, the aroma extract of soybeans exhibited the strongest...
Arai K, Misumi K, Carter SD, Shinbara S, Fujiki M, Sakamoto H.Cartilage oligomeric matrix protein (COMP) is abundant within cartilage; its turnover and/or degradation have been investigated in various equine joint diseases and it has been suggested that COMP fragmentation might be useful for monitoring such conditions. Objective: To determine whether COMP metabolism is compromised in equine osteoarthritis (OA) and whether COMP degradation is a useful joint marker representing cartilage destruction. Objective: A monoclonal antibody (mAb) with a higher affinity for degraded COMP allows discrimination of diseased joints by quantifying COMP levels and fragme...
Jackson BF, Lonnell C, Verheyen KL, Dyson P, Pfeiffer DU, Price JS.Dorsal metacarpal disease (DMD) is a common problem in 2-year-old racehorses and results in loss of a significant number of days from training. Biochemical markers of bone cell activity measured early in the training season could have value for identifying 2-year-old Thoroughbred racehorses that develop DMD. Objective: To determine the association between serum concentrations of osteocalcin, the carboxyterminal propeptide of type I collagen (PICP) and the carboxyterminal cross-linked telopeptide of type I collagen (ICTP) measured early in the training season and the risk of DMD. Methods: Blood...
Ekman S, Skiöldebrand E, Heinegård D, Hultenby K.One of the most common causes of lameness in racehorses is osteoarthritis (OA). Pathogenesis is not clear and pathological processes of the different joint tissues interact in often progressive events. The interface between cartilage and newly synthesised bone has been shown to be particularly enriched in bone sialoprotein (BSP), a cell-binding matrix protein. Objective: To establish whether changes in the concentration of BSP may serve as a marker for early biochemical changes of the subchondral bone. Methods: Articular cartilage, cartilage/bone interface and subchondral bone of the proximal ...
van den Boom R, van der Harst MR, Brommer H, Brama PA, Barneveld A, van Weeren PR, DeGroot J.Osteoarthritis (OA) is one of the most prevalent and disabling chronic conditions affecting horses and leads to degeneration of articular cartilage. Diagnosis is based on clinical signs in combination with radiography, which is relatively insensitive and provides only an indication of accumulated damage. Alternative methods, such as molecular markers, are therefore needed that can quantitatively, reliably and sensitively detect osteoarthritic changes in the joints at an early stage of the disease. If such markers are to be used reliably, it is important to know the relationship between marker ...
Céleste C, Ionescu M, Robin Poole A, Laverty S.Although intraarticular (IA) corticosteroids are frequently used to treat joint disease, the effects of their repeated use on articular cartilage remains controversial. The aim of our study was to determine the effects of a clinically recommended dose of IA triamcinolone acetonide (TA), on synovial fluid (SF) biomarkers of cartilage metabolism. Ten adult horses, free of osteoarthritis (OA) in their radiocarpal joints, were studied. One radiocarpal joint of each horse was randomly chosen for treatment and the contralateral anatomically paired joint acted as the control. Aseptic arthrocentesis w...
Chan CP, Wan TS, Watkins KL, Pelsers MM, Van der Voort D, Tang FP, Lam KH, Mill J, Yuan Y, Lehmann M, Hempel A, Sanderson JE, Glatz JF, Renneberg R.Fatty acid-binding protein (FABP) holds promise for early detection of tissue injury. This small protein (15kD) appears earlier in the blood than large proteins after cell damage. Combined its characteristics of high concentration tissue contents and low normal plasma values provide the possibility of a rapid rise above the respective reference values, and thus an early indication of the appearance of tissue injury. A general review was presented on the current status of different types of FABP for the detection of tissue injury in patients with myocardial injury, brain injury and also in athl...
van de Lest CH, Brama PA, van El B, DeGroot J, van Weeren PR.Osteochondrosis (OC) is the most important developmental orthopaedic disease in the horse. Despite some decades of research, much of the pathogenesis of the disorder remains obscure. Increasing knowledge of articular cartilage development in juvenile animals led to the presumption that the role of collagen in OC might be more important than previously thought. To study collagen characteristics of both cartilage and subchondral bone in young (5 and 11 months of age) horses, samples were taken of subchondral bone and articular cartilage from a group of 43 Dutch Warmblood foals and yearlings that...
van den Boom R, Brama PA, Kiers GH, DeGroot J, Barneveld A, van Weeren RR.Matrix metalloproteinases (MMPs) and tumour necrosis factor alpha (TNF-alpha) may be useful as biomarkers of joint disease or inflammation. However, activity of both MMPs and TNF-alpha in synovial fluid (SF) may be influenced by nonpathological factors such as arthrocentesis or exercise. Objective: To investigate the influence of repeated arthrocentesis and exercise on MMP and TNF-alpha activities in SF from normal equine joints. Methods: SF was collected from the left metacarpophalangeal, radiocarpal and tarsocrural joints of 16 horses. Eight of these horses were subsequently subjected to an ...
van den Boom R, Brama PA, Kiers GH, de Groot J, van Weeren PR.To assess the effects of age and joint disease on hydroxyproline and glycosaminoglycan (GAG) concentrations in synovial fluid from the metacarpophalangeal joint of horses and evaluate the association of those concentrations with severity of osteoarthritis and general matrix metalloproteinase (MMP) activity. Methods: Synovial fluid was collected from the metacarpophalangeal joints of foals at birth (n = 10), 5-month-old foals (10), 11-month-old foals (5), and adult horses (73). Methods: Hydroxyproline and GAG concentrations were determined in synovial fluid samples. The severity of osteoarthrit...
Billinghurst RC, Brama PA, van Weeren PR, Knowlton MS, McIlwraith CW.To determine whether serum concentrations of biomarkers of skeletal metabolism can, in conjunction with radiographic evaluation, indicate severity of osteochondrosis in developing horses. Methods: 43 Dutch Warmblood foals with varying severity of osteochondrosis. Methods: 24 foals were monitored for 5 months and 19 foals were monitored for 11 months. Monthly radiographs of femoropatellar-femorotibial and tibio-tarsal joints were graded for osteochondral abnormalities. Serial blood samples were assayed for 8 cartilage and bone biomarkers. At the end of the monitoring period, foals were examined...
Brama PA, van den Boom R, DeGroott J, Kiers GH, van Weeren PR.Matrix metalloproteinases (MMPs) are considered candidate biomarkers for both physiological and pathological tissue remodelling because of their key role in articular cartilage homeostasis. As disruption of the collagenous architecture is thought to be pivotal in chronic degenerative diseases such as osteoarthritis (OA), the collagenases form an interesting subset of the MMPs. The significance of any biomarker in synovial fluid (SF) can be assessed properly only when fluctuations in patterns induced by physiological processes such as development and growth, and by external influences and inter...
Wyse CA, Love S, Christley RM, Yam PS, Cooper JM, Cumming DR, Preston T.Oxidative stress refers to an imbalance between the production of oxidising free radicals and the antioxidant defenses of the cell, and is associated with many pathogenic processes. Oxidative damage to cellular lipids results in the evolution of pentane and ethane gas, and detection of these hydrocarbons in the exhaled breath can be used to monitor in vivo oxidative stress. The aim of this study was to validate a gas chromatography (GC) method for measurement of breath pentane in the horse. The GC-system developed showed good specificity for discrimination of pentane from other breath hydrocar...
Jackson BF, Lonnell C, Verheyen K, Wood JL, Pfeiffert DU, Price JS.Injuries to the skeleton are a major cause of morbidity and mortality in racehorses and age, gender and season have all been shown to influence risk of injury. Objective: To use biochemical markers of bone cell activity to establish to whether cellular processes in bone underlie these described effects. Methods: Blood samples were collected monthly from 2-year-old horses in race training between November 1998 and September 1999. Mean age at the start of the study was 20 months (range 18-23 months), with no significant difference in average age between colts (n = 84) and fillies (n = 63). Three...
Parashar R, Singla LD, Kaur P, Sharma SK.Relative association of haemato-biochemical findings with oxidative stress markers was evaluated between natural patent and latent infection of in horses to divulge the role of these parameters in the pathogenesis of illness due to non-availablity in literature. Blood samples were collected from 429 equines of 16 districts of the Punjab and samples positive by conventional microscopy (patent Group I; oll = 13), by polymerase chain reaction (PCR) (latent group II; = 38) and healthy control (group III, = 64) were compared for haematological-biochemical index and stress parameters....
Samuels AN, Collins NM, Hanlon K, Bartish C, Kelly P, Kamr AM, Toribio RE.Early and accurate identification of septicemia in neonatal foals improves survival. In human medicine, the neutrophil-to-lymphocyte ratio (NLR), neutrophil-to-monocyte ratio (NMR), monocyte-to-lymphocyte ratio (MLR), and plasma cell-free DNA (cfDNA) aid in early bacteremia detection. This study evaluated the diagnostic utility of these markers in conjunction with other clinical and hematological parameters in hospitalized foals < 5 days old to predict positive blood culture at admission and to distinguish between Gram-positive, Gram-negative, or polymicrobial bacteremia. A total of 391 foal...
Cullen JN, Cieslak J, Petersen JL, Bellone RR, Finno CJ, Kalbfleisch TS, Calloe K, Capomaccio S, Cappelli K, Coleman SJ, Distl O, Durward-Akhurst SA....MicroRNAs (miRNAs) are essential regulators of gene expression, yet few comprehensive databases exist for miRNA expression in non-model species, limiting our ability to characterize their roles in gene regulation, development, and disease. Similarly, isomiRs - length and sequence isoforms of canonical miRNAs with potentially altered regulatory targets and functions - have received even less attention in non-model species, including the horse, leaving a critical gap in our understanding of their biological significance. To address these challenges, we developed an open-source, containerized pip...
Berghaus LJ, Venner M, Helbig H, Hildebrandt D, Hart K.Rhodococcus equi causes pneumonia in young foals, but disease susceptibility and severity vary. Cortisol and vitamin D modulate immune responses and cytokine production during bacterial infection, and altered concentrations are associated with sepsis in neonatal foals. We hypothesised an age and disease effect on circulating steroid hormone concentrations in foals, and that differences in cytokines and steroid hormone concentrations would predict disease severity in pneumonic foals. Objective: To investigate circulating concentrations of various cytokines, cortisol and vitamin D as predictors ...
Čebulj-Kadunc N, Frangež R, Kruljc P.The aim of the study was to determine the fluctuations of selected physiological parameters in young Lipizzan stallions ( = 10) during the initial phase of their training as indicators of adaptation to a graded exercise load and stress exposure. For this purpose, four exercise tests (ExT) with lunging were carried out over a period of one year. Physiological parameters (gait speed, heart and respiratory rate (HR and RR), rectal and body surface temperature (RT and BST), and cortisol and lactate concentration (CORT and LAC)) were measured before and after training. In all ExT, gait speeds incre...
Cloteau C, Delcourt V, Loup B, Chabot B, Pescher M, Susdorf E, Kaabia Z, Garcia P, Popot MA, Le Bizec B, Dervilly G, Bailly-Chouriberry L.Biomarker identification by mass spectrometry represents a key step in the workflow of nontargeted metabolomic studies. Given the complexity of the data, this step, which must be carried out by a trained specialist, is time-consuming, and the biomarkers discovered are not always identified. While this stage is not an obstacle to the development of new screening and classification tools, it is nonetheless crucial to a better understanding of the results obtained. For this reason, the aim of this study was to perform structural elucidation of candidate biomarkers, which had previously been displ...
Lugo T, Myers S, Nguyen TA.In vitro models have revolutionized our understanding of biological pathways and mechanisms, offering a viable alternative to direct patient testing. However, there is a significant lack of models for different animals, particularly equine models. This study presents a novel primary cell culture extracted from a 3-year-old horse diagnosed with multisystemic eosinophilic epitheliotropic disease. Tissue samples were collected from lymph nodes at various locations. Growth curves of extracted primary cells were analyzed and the optimal conditions were assessed. Biomarkers, such as CD31, ZO-1, CD79...
Muderspach ND, Daucke R, Nielsen MW, Scoggin KE, Fedorka CE, Miller LMJ, May MG, Troedsson MHT, Ferreira-Dias G, Agerholm JS, Schoof EM....Endometrial fibrosis leads to subfertility when periglandular fibrosis impairs endometrial gland function. Identifying distinct protein expressions in mares suffering from this condition is essential for understanding the pathogenesis and developing treatments to delay fibrotic progression. To gain a better understanding of protein dynamics underlying this condition, Data-Independent Acquisition Mass Spectrometry was utilized to comprehensively characterize and compare the equine endometrial and plasma proteome from mares with different severities of endometrial fibrosis. Mares in diestrus wer...
Beermann A, Hamza E, Reinhard S, Koch C, Oberhänsli T, Unger L.We investigated microRNAs (miRNAs) as potential prognostic biomarkers for equine sarcoid (ES) disease. In a breed-, age-, and sex-matched case-controlled study involving 45 ES-affected and 15 control horses, we assessed the diagnostic, prognostic, and theragnostic value of 3 miRNAs (eca-miR-127, eca-miR-379, eca-miR-432) in horses treated with European mistletoe () extract versus placebo. Whole-blood miRNA concentrations were measured using reverse-transcription quantitative real-time PCR (RT-qPCR) at 3 different times. We found that eca-miR-432 expression was lower in ES-affected (median =...
Meiseberg LK, Mergani A, Delarocque J, Imker R, Köhn D, Wanes D, Bonilla MC, Veldhuizen EJA, von Köckritz-Blickwede M, Ohnesorge B, de Buhr N.Equine asthma (EA) is the most prevalent chronic lung disease in horses. Neutrophils are the main effector cells in severe EA. Neutrophil extracellular traps (NETs) have been described as contributors to severity in human asthma and chronic obstructive pulmonary disease. Thus, we aimed to investigate if NET-related factors in equine neutrophils, blood and bronchoalveolar lavage fluid (BALF) allow us to differentiate EA severities and to identify NET-related mechanistic insights in EA. We quantified NETs and NET-related factors in the blood and BALF of eight healthy horses and 18 horses with di...
de Lara NSS, Weiss RR, Oba E, Kozicki LE, Souza FA, Bergstein-Galan TG, Muehlbauer E, Silvestri M, de Lima PHL, Vaz ES.In equine reproduction, determining foetal sex is of economic and strategic importance, but currently available methods are often invasive, costly, or require specialised expertise. This study aimed to assess whether plasma progesterone concentrations could serve as a predictive tool for foetal sex determination in Criollo mares between the 4th and 8th months of gestation and to determine whether these measurements could identify foetal sex. Blood samples were collected at 30-day intervals from 17 Crioula mares between 114 days and 240 days of gestation. Maternal plasma progesterone concen...
Nilsson E, Moazzami AA, Lindberg JE, Jansson A.Feeding a high amount of starch-rich grains is common practice for performance horses even though the horse has evolved to eat a grass based, i.e. low starch diet. To our knowledge, there are no studies using metabolomics to investigate the effects of a high-starch diet in horses. In this study we investigated differences in the plasma metabolic profile of 6 Standardbred horses fed a no-starch, forage-only (F) diet or a high-starch forage-concentrate (FC) diet for 29 days, respectively in a cross-over design. Postprandial plasma samples were collected on the morning of day 25 of each dietary ...
Hobbs KJ, Ludwig EK, Martin EM, Bayless R, Bauck AG, Freeman DE, Gonzalez LM.To determine if blood and peritoneal fluid levels of syndecan-1, heparan sulfate, and hyaluronan are elevated in horses with small intestinal disease compared to healthy counterparts. Unassigned: 61 horses were categorized into control (n = 20), inflammatory (11), and strangulating (30) groups. Paired peritoneal fluid and blood samples were obtained from each group from December 2016 through December 2024 and analyzed via equine-validated ELISAs for syndecan-1, heparan sulfate, and hyaluronan concentrations. Patient survival to discharge was recorded for all groups. Immunofluorescence staining...
Corradini I, Jose-Cunilleras E, Nolis P, López-Murcia MM, Mayordomo-Febrer A.This study aims to generate foundational metabolomic data of aqueous humor (AH) in healthy horses and donkeys, and to investigate potential changes or trends in the metabolomic profile associated with age, sex or ocular pathology in horses. The AH metabolomic fingerprint from 5 donkeys and 35 equine eyes (17 controls, 8 with cataracts, 6 with retinal disease and 4 with anterior chamber disease (ACD)) were analyzed using nuclear magnetic resonance (NMR) spectroscopy. A linear mixed-effects model, with individual horse as a random effect and group as a fixed effect, with multiple testing correct...
Hammack SM, Moshage SG, Kersh ME, McCoy AM.To quantify circulating levels of myokines with a known role in bone remodeling (receptor activator of nuclear factor κ B ligand [RANK-L], matrix metalloproteinase 2 [MMP-2], and irisin) in foals in response to exercise and over the first year of life. Unassigned: 12 foals were enrolled in the study; 6 underwent an 8-week exercise program, and 6 were nonexercised controls. Blood samples were collected between 2 and 11 months of age. Receptor activator of nuclear factor κ B ligand, MMP-2, and irisin were quantified using equine-specific ELISAs. Unassigned: RANK-L, MMP-2, and irisin did not ch...
Barbosa B, Santi TF, Rodak AC, Nogara MF, Leite LMB, Weber SH, Niels C, Daros RR, Michelotto PV.The analysis of equine exhaled breath condensate (EBC) lacks standardized methodology, and current collection devices are often adapted for research. This study evaluates a novel horse-specific EBC collector and assesses the variability of EBC pH and hydrogen peroxide (HO) levels, exploring potential correlations with bronchoalveolar lavage (BAL) and tracheal wash (TW) cytology. Eleven healthy mixed-breed mares from a teaching herd, with no evidence of airway abnormalities, were included in this randomized observational study. The collection efficiency of the proposed device was assessed, and ...
Austin MMP, Ivey JLZ, Shepherd EA, Myer PR.Starvation in horses presents critical welfare, economic, and management challenges with underlying molecular mechanisms of metabolic modification and recovery left poorly defined. Prolonged caloric deprivation induces significant systemic shifts in carbohydrate, protein, and lipid metabolism, reflected in coordinated changes in tissue-specific gene expression. This review synthesizes current knowledge on equine metabolic responses to starvation, emphasizing pathways found through RNA sequencing (RNA-seq) and real-time quantitative polymerase chain reaction (RT-qPCR) studies. Molecular investi...
Hanousek K, O'Hara V, Riddell DO, Piercy RJ.In Thoroughbred horses, a highly prevalent short interspersed nuclear element (SINE) mutation in the myostatin gene (MSTN) promoter influences circulating myostatin concentration and is associated with muscle morphology, fracture risk and optimal race distance. Our prior data reveal that within horses there is substantial variation in serum myostatin concentration, particularly in MSTN heterozygotes and wild type horses but it was unclear whether such variation relates to within-horse differences or to environmental or temporal effects. Here we report the intra-horse consistency of circulating...
The aim of the study was to identify proteomic signatures from the serum of horses affected by simple obstructive intestinal colic to characterize the pathological process and to assess potential biomarkers for early diagnosis. Seven horses with obstructive colic received venous blood samples for determination of standard hematobiochemical, inflammatory, and lipid profiles at the time of initial clinical examination and after conservative therapy upon recovery. Proteomic profiling was also performed on all samples by means of a within-group analysis (sick horses at discharge vs. sick horses at...
Ali A, Derar DR, Alaeyeari AA, Alharbi YM.This study aimed to monitor intrauterine fetal growth, establish predictive equations for gestational age estimation, and determine the optimal period for fetal sexing in Arabian horses using ultrasonography. Unassigned: Seven Arabian mares were monitored from insemination to parturition using transrectal ultrasonography. The following fetal and embryonic parameters were measured: embryonic vesicle (EV), crown-rump length (CRL), biparietal diameter (BIP), stomach diameter (STD), chest depth (CHD), abdominal diameter (ABD), kidney length (KDL), eyeball diameter (EBD), and eye lens length (ELL)....
Micheau L, Audigié F, Moiroud C, Jacquet S.Disuse-induced bone loss during stall confinement and immobilization is a major concern in horses because it impairs recovery and increases susceptibility to further injury. Experimental models are needed to evaluate therapeutic options, but most available equine models rely on cast immobilization, which is technically demanding and may be associated with complications. This study aimed to assess a simpler and less restrictive model to induce a quantifiable decrease in bone density in horses. Six French Standardbred horses underwent eight weeks of stall confinement, with a wooden wedge fitted ...
Giannone C, Atallah E, Dalla Costa E, Benetti E, Santolini E, Tassinari P, Bovo M.Technology for monitoring behaviour and health of horses has evolved significantly, presenting new opportunities and challenges in equine management and healthcare. This scoping review consolidates recent findings on wearable sensors and non-contact technologies, discussing their benefits and limitations. Among these advancements, heart rate monitors stand out as a key point in equine monitoring. By tracking heart rate variability, devices help monitor cardiac autonomic regulation, optimise training regimens and allow early detection of cardiac issues, although accuracy can be compromised by i...
Pennington MV, Zoller JL, White-Springer SH, Harlin JF, Huseman CJ, Leatherwood JL, O'Reilly CL.Competition stress is a common factor influencing the success of performing athletes. However, few studies have quantified the physiological stress responses in horses and riders surrounding an equestrian event. Objective: The objectives of the current study were to determine salivary cortisol concentrations (SCC) as an indicator of stress in fifteen horse and rider pairs competing in western stock horse events and to investigate the relationship between SCC and performance. Methods: Subjects included male and female Quarter horses aged 3-15 years and equestrians aged 18-22 years. Salivary sam...
Sullivan J, Blea J, Morales CJ, McKemie DS, Kass PH, Knych HK.Corticosteroids, such as isoflupredone, are effective anti-inflammatory medications and as such are commonly used to treat inflammation associated with training and injuries in performance horses. While the pharmacokinetics and pharmacodynamics of isoflupredone acetate (IPA) following intra-articular administration to horses has been well described, studies characterizing intramuscular (IM) administration are lacking. The objective of the current study was to describe the pharmacokinetics and anti-inflammatory effects of IPA following IM administration to horses. Twelve horses received a singl...
Training on deep sand is commonly employed in endurance horses, but its physiological adaptation remains poorly characterized. This study aimed to characterize locomotor adaptations during a 7 km controlled-speed canter on deep sand in eighteen endurance horses, to identify heart rate variability (HRV) components, and to investigate changes in hematological variables before and after exercise. Stride frequency (SF) and stride length (SL), HRV, and hematological profiles were recorded during exercise and recovery with a fitness tracker. Associations between maximum speed and locomotor parameter...
Donnelly CG, Peng S, Pflieger L, Manfredi J, Coleman M, Rappaport N, Price ND, Finno CJ.Metabolic syndrome (MetS)-encompassing obesity, insulin resistance, dyslipidemia, and hypertension-is prevalent in both humans and horses, offering a unique opportunity to explore shared pathophysiological mechanisms across species in a controlled model organism. In this first report from the Pioneer 100 Horse Health Project (P100HHP), we conducted a longitudinal, multi-omic analysis of 108 deeply phenotyped horses to interrogate individual health trajectories for precision insights into MetS. We identified two primary metabotypes: one characterized by elevated unsaturated triglycerides (TGs) ...
McAdams ZL, Campbell EJ, Dorfmeyer RA, Turner G, Shaffer S, Ford T, Lawson J, Terry J, Raju M, Coghill L, Cresci L, Lascola K, Pridgen T....Horses and other equids are reliant on the gut microbiome for health, and studies have reported associations between certain clinical conditions and features of the fecal microbiome. However, research to date on the equine fecal microbiome has often relied on small sample sizes collected from single and relatively localized geographic regions. Previous work also largely employs single timepoint analyses, or horses selected based on limited health criteria. Results: To address these limitations and expand our understanding of the core microbiome in health, and the changes associated with advers...
Jandová V, Huber N, AlMheiri FG, Bábor K, Trachsel DS.Stress represents a serious health and welfare concern; however, its objective assessment remains difficult. The equine gastric ulcer syndrome (EGUS) and orthopedic diseases that cause pain are among stress associated diseases in equine medicine. The leukocyte coping capacity (LCC) quantifies oxygen radical generation of neutrophil granulocytes which is altered under stress. Therefore, LCC could be a novel biomarker for stress in horses and we hypothesized that horses with stress associated diseases would have lower LCC values in comparison to horses without these diseases. Methods: In this ob...
Satué K, Fauci D, Fazio E, Velasco-Martínez MG, Bruschetta G, Medica P.This study investigates sequential changes in serum protein fractions during gestation in 31 pregnant Spanish Purebred mares compared to 15 non-pregnant control. Total serum proteins (TSP) were measured using the Biuret method, while albumin (ALB), total globulins (tGLOB), and their subfractions (α₁, α₂, β₁, β₂, γ-GLOB) were analyzed by agarose gel electrophoresis. Pregnant mares showed significant changes in serum protein profiles throughout gestation. TSP and tGLOB concentrations increased from mid to late pregnancy (months 6-11), while ALB concentrations declined between months...
Marković L, Vićić I, Lazarević Macanović M, Francuski Andrić J, Kovačević Filipović M, Radaković M.Working horses often develop distinct patterns of joint degeneration, yet research in this population remains limited. This study aimed to characterize degenerative changes in the metacarpophalangeal (MCP) and metatarsophalangeal (MTP) joints of Serbian Mountain Horses using computed tomography (CT) and to explore their associations with synovial fluid (SF) biomarkers. A cross-sectional analysis was conducted on 32 MCP/MTP joints from eight clinically sound horses. Postmortem, joints underwent CT imaging, and SF samples were analyzed for viscosity, protein content, total nucleated cell count (...
