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Topic:Horses

"Horses" is a broad topic that encompasses various aspects of equine biology, behavior, and management. This category includes studies on the anatomy, physiology, and genetics of horses, as well as their behavior, nutrition, and care. Research in this area may also cover the historical and cultural significance of horses, their roles in agriculture, sport, and therapy, and the challenges associated with their conservation and welfare. The page aggregates peer-reviewed research articles and scholarly studies that explore the multifaceted relationships between humans and horses, examining both scientific and socio-economic perspectives.
Horse allergy: Curly Horses can mediate immune tolerance.
Pneumologie (Stuttgart, Germany)    October 12, 2023   Volume 78, Issue 1 47-57 doi: 10.1055/a-2101-9533
Mitlehner A, Mitlehner C, Reißmann M, Stoll P, Swoboda I, Mitlehner W.American Bashkir Curly Horses are claimed to be hypoallergenic, but this has not been clinically proven. In the present study, the effect of exposure to Curly Horses was investigated in 141 patients allergic to horses by measuring their lung function and nasal patency during Curly Horse contact. Continuous contact with Curly Horses, including riding and brushing, decreased the allergic riders' reactivity as measured by FEV1, PEF, and PNIF. Subsequent visits (up to 40 or more hours of riding) further reduced reactivity to the Curly Horses. Allergic events to horses occurred only in 72 out of 13...
Comparing Inertial Measurement Units to Markerless Video Analysis for Movement Symmetry in Quarter Horses.
Sensors (Basel, Switzerland)    October 12, 2023   Volume 23, Issue 20 8414 doi: 10.3390/s23208414
Pfau T, Landsbergen K, Davis BL, Kenny O, Kernot N, Rochard N, Porte-Proust M, Sparks H, Takahashi Y, Toth K, Scott WM.With an increasing number of systems for quantifying lameness-related movement asymmetry, between-system comparisons under non-laboratory conditions are important for multi-centre or referral-level studies. This study compares an artificial intelligence video app to a validated inertial measurement unit (IMU) gait analysis system in a specific group of horses. Methods: Twenty-two reining Quarter horses were equipped with nine body-mounted IMUs while being videoed with a smartphone app. Both systems quantified head and pelvic movement symmetry during in-hand trot (hard/soft ground) and on the l...
A Translational Model for Repeated Episodes of Joint Inflammation: Welfare, Clinical and Synovial Fluid Biomarker Assessment.
Animals : an open access journal from MDPI    October 12, 2023   Volume 13, Issue 20 doi: 10.3390/ani13203190
Kearney CM, Korthagen NM, Plomp SGM, Labberté MC, de Grauw JC, van Weeren PR, Brama PAJ.This study investigates repeated low-dose lipopolysaccharide (LPS) injections in equine joints as a model for recurrent joint inflammation and its impact on animal welfare. Joint inflammation was induced in eight horses by injecting 0.25 ng of LPS three times at two-week intervals. Welfare scores and clinical parameters were recorded at baseline and over 168 h post-injection. Serial synoviocentesis was performed for the analysis of a panel of synovial fluid biomarkers of inflammation and cartilage turnover. Clinical parameters and a final synoviocentesis were also performed eight weeks after t...
Olfactory Stimulation as Environmental Enrichment for Domestic Horses-A Review.
Animals : an open access journal from MDPI    October 12, 2023   Volume 13, Issue 20 3180 doi: 10.3390/ani13203180
Bini de Lima AC, Sebastião da Fé VC, Palermo Hernandes MS, Oliveira Dos Santos VM.Horses constantly face several challenges inherent to the domestic environment, and it is common for the expression of their natural behavior to be drastically limited. Environmental enrichment has been suggested as an alternative to improve the captive situation of domestic horses. Among the recently proposed enrichment strategies, olfactory stimulation has emerged as a method for improving several aspects related to animal behavior. Olfaction is a sensory modality that plays a significant role in the expression of equine behavior, and in recent years, studies have shown that olfactory stimul...
Carbon emissions from Australian Sphagnum peatlands increase with feral horse (Equus caballus) presence.
Journal of environmental management    October 11, 2023   Volume 347 119034 doi: 10.1016/j.jenvman.2023.119034
Treby S, Grover SP.Peatlands are globally significant carbon sinks, but when disturbed, have the potential to release carbon back to the atmosphere as greenhouse gases. Feral horse populations in the Australian Alps degrade Sphagnum peatlands, which are highly sensitive to disturbance. However, the link between this degradation and peatland carbon cycling is not understood. Here, we compared the autumn daytime carbon dioxide (CO) and methane (CH) fluxes of 12 alpine and subalpine Sphagnum peatlands in Kosciuszko National Park, Australia. The presence of feral horses at these sites was correlated with higher carb...
Decoding the transcriptomic expression and genomic methylation patterns in the tendon proper and its peritenon region in the aging horse.
BMC research notes    October 11, 2023   Volume 16, Issue 1 267 doi: 10.1186/s13104-023-06562-1
Pechanec MY, Mienaltowski MJ.Equine tendinopathies are challenging because of the poor healing capacity of tendons commonly resulting in high re-injury rates. Within the tendon, different regions - tendon proper (TP) and peritenon (PERI) - contribute to the tendon matrix in differing capacities during injury and aging. Aged tendons have decreased repair potential; the underlying transcriptional and epigenetic changes that occur in the TP and PERI regions are not well understood. The objective of this study was to assess TP and PERI regional differences in adolescent, midlife, and geriatric horses using RNA sequencing and ...
Detection of Selected Equine Respiratory Pathogens in Stall Samples Collected at a Multi-Week Equestrian Show during the Winter Months.
Viruses    October 11, 2023   Volume 15, Issue 10 doi: 10.3390/v15102078
Lawton K, Runk D, Hankin S, Mendonsa E, Hull D, Barnum S, Pusterla N.The aim of this study was to use environmental sampling to determine the frequency of detection of selected equine respiratory viruses and bacteria in horses attending a multi-week equestrian show during the winter months. At four time points during showing, environmental sponge samples were collected from all stalls on the property and tested for the presence of equine herpesvirus-1 (EHV-1), EHV-2, EHV-4, equine influenza virus (EIV), equine rhinitis B virus (ERBV), Streptococcus equi ss. equi (S. equi), and S. equi ss. zooepidemicus (S. zooepidemicus) using real-time PCR (PCR). Environmental...
Characterization of gastrointestinal inflammatory cell type in equine glandular gastric disease.
American journal of veterinary research    October 11, 2023   Volume 84, Issue 12 ajvr.23.06.0129 doi: 10.2460/ajvr.23.06.0129
Banse HE, Piero FD, Andrews FM, Garcia-Abarca N, Watanabe TTN.To compare small intestinal inflammation with gastric inflammation in horses with and without equine gastric glandular disease (EGGD), we evaluated endoscopic, macroscopic, and microscopic findings of the glandular stomach and microscopic findings of the small intestine. Methods: 36 horses. Methods: Horses underwent endoscopy and were scored for EGGD. After euthanasia, stomachs were collected and macroscopically evaluated. Normal pyloric mucosa, glandular lesions, and small intestinal (duodenum, mid-jejunum, and ileum) samples were collected and processed for microscopic examination. Cellular ...
Low-Field Magnetic Resonance Imaging Findings of the Fetlock Region of Nonracehorses.
Journal of equine veterinary science    October 11, 2023   Volume 132 104938 doi: 10.1016/j.jevs.2023.104938
Auth AK, Hinnigan GJ, Smith MA, Owen KR.Low-field, magnetic resonance imaging (MRI) is an advanced imaging modality widely used to diagnose distal limb pathology in horses, but there are limited data regarding lesion distribution within the metacarpo/metatarsophalangeal joint (MCP/MTPJ) region in lame nonracehorses. The aim of this study was to describe the low-field MRI findings and lesion distribution in nonracehorses with MCP/MTPJ region pain. Clinical records from horses undergoing MRI of the MCP/MTPJ region between July 2016 and March 2023 were reviewed. Horses were included if pain causing lameness was localized to this region...
Myosin heavy-chain myopathy in 2 American quarter horses.
Veterinary pathology    October 11, 2023   Volume 61, Issue 3 462-467 doi: 10.1177/03009858231204253
Faccin M, Landsgaard KA, Milliron SM, Jennings AH, Keith Chaffin M, Giaretta PR, Rech RR.A 1.5-year-old American quarter horse gelding (case 1) and an 11-month-old American quarter horse filly (case 2) were presented for acute onset pelvic lameness and lethargy. Case 1 had nasal discharge, while case 2 developed rapid muscle atrophy. Both horses had elevated serum creatine kinase activity. The horses showed similar polyphasic histiocytic and lymphoplasmacytic myositis with necrosis, mineralization, and regeneration. Additionally, case 1 had Streptococcus equi subsp. equi-induced suppurative retropharyngeal lymphadenitis with renal purpura hemorrhagica and myoglobinuric nephropathy...
The Use of Innovative Diagnostics to Inform Sustainable Control of Equine Helminth Infections.
Pathogens (Basel, Switzerland)    October 11, 2023   Volume 12, Issue 10 1233 doi: 10.3390/pathogens12101233
Matthews JB, Peczak N, Lightbody KL.Helminths are commonly found in grazing equids, with cyathostomin nematodes and the cestode being the most prevalent. Most horses harbour low burdens of these parasites and do not develop signs of infection; however, in a small number of animals, high burdens can accumulate and cause disease. Cyathostomins are associated with a syndrome known as larval cyathostominosis. This occurs when large numbers of larvae emerge from the large intestinal wall. This disease has a case fatality rate of up to 50%. infection has been associated with various types of colic, with burdens of >20 worms assoc...
Efficacy and Safety of Subcutaneous Allergen-Specific Immuno-Therapy in Horses with Allergic Cutaneous and Respiratory Diseases-A Systematic Review.
Veterinary sciences    October 10, 2023   Volume 10, Issue 10 doi: 10.3390/vetsci10100613
Herrmann I, Sanchez AJ.Allergen-specific immunotherapy (AIT) is the only current intervention that has the ability to modify the immune response toward a tolerogenic state. This study aimed to assess the efficacy and safety of AIT in horses with allergic diseases in a systematic manner. Three databases were searched to identify articles reporting clinical outcomes and adverse events associated with AIT. The articles were evaluated for beneficial responses to AIT, defined as a ≥50% reduction in clinical signs, and clinical remission. Horses with respiratory diseases, urticaria, and pruritic dermatitis receiving ins...
Chemical composition of horse hooves with functional qualities for competing barefoot.
Journal of animal science    October 10, 2023   Volume 101 doi: 10.1093/jas/skad346
Spörndly-Nees E, Jansson A, Pökelmann M, Pickova J, Ringmark S.Barefoot racing is a common practice within the harness racing industry, but not all horses have hooves of sufficient quality to race sustainably without shoes. There is currently no objective approach available to assess whether a horse's hooves are suitable for barefoot racing, raising animal welfare issues if trainers misjudge the functional qualities of hooves. This study compared chemical composition of the hoof wall and fatty acid (FA) composition of the digital cushion in a group of horses that had raced barefoot often (RB) and a group of horses that could not race barefoot and therefor...
Additional evidence supports GRM6 p.Thr178Met as a cause of congenital stationary night blindness in three horse breeds.
Veterinary ophthalmology    October 10, 2023   doi: 10.1111/vop.13151
Esdaile E, Knickelbein KE, Donnelly CG, Ferneding M, Motta MJ, Story BD, Avila F, Finno CJ, Gilger BC, Sandmeyer L, Thomasy S, Bellone RR.Congenital stationary night blindness (CSNB) is an ocular disorder characterized by nyctalopia. An autosomal recessive missense mutation in glutamate metabotropic receptor 6 (GRM6 c.533C>T, p.(Thr178Met)), called CSNB2, was previously identified in one Tennessee Walking Horse and predicted to reduce binding affinity of the neurotransmitter glutamate, impacting the retinal rod ON-bipolar cell signaling pathway. Thus, the first aim was to identify the allele frequency (AF) of CSNB2 in breeds with reported cases of CSNB and breeds closely related to the Tennessee Walking Horse. The second aim ...
Normal variation in pelvic roll motion pattern during straight-line trot in hand in warmblood horses.
Scientific reports    October 10, 2023   Volume 13, Issue 1 17117 doi: 10.1038/s41598-023-44223-2
Byström A, Hardeman AM, Engell MT, Swagemakers JH, Koene MHW, Serra-Bragança FM, Rhodin M, Hernlund E.In horses, hip hike asymmetry, i.e. left-right difference in hip upwards movement during hind limb protraction in trot, is a crucial lameness sign. Vertical hip movements are complex, influenced by both pelvic roll and pelvic vertical motion. Veterinarians find it challenging to identify low-grade lameness, and knowledge of normal variation is a prerequisite for discerning abnormalities. This study, which included 100 clinically sound Warmblood horses, aimed to describe normal variation in pelvic roll stride patterns. Data were collected during straight-line trot in hand using optical motion c...
Horse Whole Blood Trace Elements from Different Sicily Areas: Biomonitoring of Environmental Risk.
Biological trace element research    October 10, 2023   doi: 10.1007/s12011-023-03889-5
Nava V, Licata P, Biondi V, Catone G, Gugliandolo E, Pugliese M, Passantino A, Crupi R, Aragona F.Horses are excellent bioindicators for the assessment of environmental pollution. The aim of this study was to evaluate the levels and potential bioaccumulation of 28 mineral elements in 75 horse whole blood samples collected from five pollution-prone areas of Sicily, Italy. A direct mercury analyzer (DMA-80) was used for Hg determination, and an inductively coupled plasma mass spectrometer (ICP-MS) for all other elements. A one-way ANOVA test, followed by Bonferroni's multiple comparison for post hoc comparison, was applied to assess statistically significant differences between mineral eleme...
Intra-articular bone marrow mononuclear cell therapy improves lameness from naturally occurring equine osteoarthritis.
Frontiers in veterinary science    October 9, 2023   Volume 10 1256284 doi: 10.3389/fvets.2023.1256284
Everett JB, Menarim BC, Barrett SH, Bogers SH, Byron CR, Pleasant RS, Werre SR, Dahlgren LA.Osteoarthritis (OA) can be debilitating and is related to impaired resolution of synovial inflammation. Current treatments offer temporary relief of clinical signs, but have potentially deleterious side effects. Bone marrow mononuclear cells (BMNC) are a rich source of macrophage progenitors that have the ability to reduce OA symptoms in people and inflammation in experimentally-induced synovitis in horses. The objective of this study was to evaluate the ability of intra-articular BMNC therapy to improve clinical signs of naturally occurring equine OA. Horses presenting with clinical and radio...
Potential impact of natural conditions on the rostral oral health: a study of horses in Iceland.
Journal of the American Veterinary Medical Association    October 9, 2023   Volume 261, Issue S2 S108-S113 doi: 10.2460/javma.23.06.0303
Hain AM, Þórisdóttir SL, Tretow M, Bienert-Zeit A.In the context of a study of Equine Odontoclastic Tooth Resorption and Hypercementosis (EOTRH), elderly Icelandic horses were examined in their originating country. The subject of this survey was the impact of dental treatment and keeping and feeding management on the health of the rostral oral cavity. A total of 170 horses (aged ≥ 15) located in different areas of Northwest, West, and South Iceland. The horse owners completed a questionnaire about keeping, feeding, and preventative dental care. The horses were clinically examined with particular attention to gingival and dental disorders of...
Efficient primary surgical treatment of equine infectious sinusitis reduces postoperative aftercare and increases outcome results: a retrospective study of 130 cases.
Journal of the American Veterinary Medical Association    October 9, 2023   Volume 261, Issue S2 S87-S95 doi: 10.2460/javma.23.05.0298
Leps A, Korsos S, Clarysse M, Vlaminck L.To document the long-term outcome of surgically treated primary and dental-related sinusitis in horses and to describe a simple protocol for postoperative management. All surgically treated sinusitis cases referred between January 2016 and June 2022 were reviewed. Cases diagnosed with primary and dental-related sinusitis and with a follow-up of at least 6 months after hospital discharge were included. Cases with other sinus pathology were excluded. 130 cases met the inclusion criteria. 104 out of 130 were treated with sinoscopy and 26/130 with sinusotomy. 86 out of 130 cases (66.2%) were diagn...
Development and evaluation of a real-time quantitative PCR for the detection of equine infectious anemia virus.
Microbiology spectrum    October 9, 2023   e0259923 doi: 10.1128/spectrum.02599-23
Li S, Guo K, Wang X, Lin Y, Wang J, Wang Y, Du C, Hu Z, Wang X.Equine infectious anemia (EIA) has a worldwide distribution and causes severe economic losses to the equine industry. The EIA virus (EIAV) genome sequences from different countries are highly diverse, which poses a great challenge for pathogen identification with PCR. Phylogenetic analysis showed that although gag is the most conserved structural gene, it still has great genome variability. Currently, most existing PCR methods are designed based on the gag gene sequence and therefore do not cover all the viral strains, especially Asian EIAV strains. In this study, we developed a tat-gag-based ...
Investigation of Serum Markers of Hepatic Fibrosis in Equids.
Journal of equine veterinary science    October 8, 2023   Volume 131 104937 doi: 10.1016/j.jevs.2023.104937
Potier JFN, Durham AE, Modi R, Rosenberg W, Dash SA.Liver disease is common in equine practice, and treatment and prognosis are dependent on histopathologic examination of biopsies. Liver biopsy is invasive and expensive which restricts its use. Serum markers are used to predict hepatic fibrosis in humans. This study aimed to investigate the enhanced liver fibrosis (ELF) test, based on serum Hyaluronic Acid (HA), procollagen III N-terminal peptide (PIIINP), and tissue inhibitor of metalloproteinase 1 (TIMP-1) to detect hepatic fibrosis in equids. Four groups were included; two with increased serum concentrations of liver-derived enzymes and a l...
Time-Budget and Welfare Indicators of Stabled Horses in Three Different Stall Architectures: A Cross-Sectional Study.
Journal of equine veterinary science    October 7, 2023   Volume 131 104936 doi: 10.1016/j.jevs.2023.104936
Carvalho Seabra J, Martinez do Vale M, Spercoski KM, Hess T, Patricio Viviani de Moura P, Dittrich JR.Keeping horses in single stalls can lead to the development of abnormal and stereotypic behaviors (ASB). Opportunities for social interactions and stall architecture can influence behavior. The current study aimed to identify how three different stall architectures influenced time-budget and physiological parameters in horses. Stall types included: (1) 3.2 × 3.7 m with tactile contact between horses (B1); (2) 2.6 × 3.5 m with visual contact between horses and outside view (B2); (3) 2.3 × 3.4 m with visual contact and outside view (B3). Ten horses from B1 and B3, and nine from B2 were ...
Equine tapeworm (Anoplocephala spp.) infection: evaluation of saliva- and serum-based antibody detection methods and risk factor analysis in Slovak horse populations.
Parasitology research    October 7, 2023   Volume 122, Issue 12 3037-3052 doi: 10.1007/s00436-023-07994-1
Burcáková L, Königová A, Kuzmina TA, Austin CJ, Matthews JB, Lightbody KL, Peczak NA, Syrota Y, Várady M.A lack of accurate information on the prevalence and distribution of Anoplocephala spp. infections on horse farms has led to insufficient attention to tapeworm control and increasing horse anoplocephaloses in Europe. Our study aimed to examine the occurrence of Anoplocephala spp. infection using coprological, serum- and saliva-based antibody detection methods and to analyze the risk factors associated with tapeworm infection in domestic horses in Slovakia. Fecal, serum, and saliva samples were collected from 427 horses from 31 farms in Slovakia. Additionally, a questionnaire study was conducte...
Right dorsal colitis in horses: A multicenter retrospective study of 35 cases.
Journal of veterinary internal medicine    October 6, 2023   Volume 37, Issue 6 2535-2543 doi: 10.1111/jvim.16884
Flood J, Byrne D, Bauquier J, Agne GF, Wise JC, Medina-Torres CE, Wood K, Sullivan O, Stewart AJ.Right dorsal colitis (RDC) is a nonsteroidal anti-inflammatory drug (NSAID) induced, protein losing enteropathy in horses associated with a high case fatality rate. Objective: To describe signalment, NSAID usage, clinical presentations, clinical pathology, ultrasonographic findings, treatments, outcomes, and factors associated with survival in horses diagnosed with RDC. Methods: Thirty-five horses from 7 Australian equine hospitals diagnosed with RDC. Methods: Retrospective case series. Clinical records of cases were accepted if definitively or presumptively diagnosed by an internist with RDC ...
Hormone extraction from horses for use in farm animals.
The Veterinary record    October 6, 2023   Volume 193, Issue 7 288-289 doi: 10.1002/vetr.3531
Fox MW.No abstract available
Outcome and racing performance following standing fracture repair in 245 horses.
Equine veterinary journal    October 6, 2023   doi: 10.1111/evj.14016
Colgate VA, Robinson N, Barnett TP, Bathe AP, Coleridge MOD, Smith LCR, Payne RJ.Repair of sagittal proximal phalanx (P1) and parasagittal metacarpal/metatarsal III (MC/MTIII) fractures has evolved over recent decades from a procedure carried out solely under general anaesthesia, to one commonly performed under standing sedation. To date, standing fracture repair has not been evaluated for large cohorts. Objective: To determine short-term (survival to discharge) and long-term (return to racing) outcomes of horses undergoing standing repair of MC/MTIII and P1 fractures, and to compare pre-surgical and post-surgical racing performance. Methods: Single-centre retrospective co...
Diagnosis of equine pituitary pars intermedia dysfunction.
Veterinary journal (London, England : 1997)    October 6, 2023   Volume 300-302 106036 doi: 10.1016/j.tvjl.2023.106036
Stewart AJ, Ireland JL, Durham AE, McGowan CM.Equine pituitary pars intermedia dysfunction (PPID) is common in aged horses. The majority of horses respond well to treatment, but treatment is lifelong, meaning accurate diagnosis of PPID is important. Similar to any condition, there is no perfect laboratory test to diagnose PPID and accuracy is affected by the characteristics of the population in which the test is being evaluated. This review details the importance of consideration of clinical factors and diagnostic test accuracy. Basal adrenocorticotrophic hormone (ACTH) concentration is used most frequently in practice and has very good d...
Haemato-biochemical characterization of equine piroplasmosis asymptomatic carriers and seropositive, real-time PCR negative horses.
Veterinary parasitology    October 5, 2023   Volume 323 110046 doi: 10.1016/j.vetpar.2023.110046
Dorrego A, Camino E, Gago P, Buendia-Andres A, Acurio K, Gonzalez S, de Juan L, Cruz-Lopez F.Equine piroplasmosis (EP) is caused by Theileria equi and Babesia caballi, transmitted by tick vectors. Horses can suffer an acute, subacute, and chronic forms of the disease, with clinical signs such as poor performance, fever, pale mucosal membranes, and jaundice. The diagnosis of EP subclinical cases is complex due to the sensitivity of real-time PCR and the limited parasite load in some carriers, making it challenging to differentiate them from seropositive, PCR negative (S+PCR-) individuals. This study aimed to describe haematological and biochemical changes in asymptomatic EP carriers, E...
Evaluation of seasonal influences on adrenocorticotropic hormone response to the thyrotropin-releasing hormone stimulation test and its accuracy for diagnosis of pituitary pars intermedia dysfunction.
Veterinary journal (London, England : 1997)    October 5, 2023   Volume 300-302 106035 doi: 10.1016/j.tvjl.2023.106035
Adams AA, Siard-Altman MH, Reedy SE, Barker D, Elzinga S, Sanz MG, Urschel K, Ireland JL.Pituitary pars intermedia dysfunction (PPID) is an age-related neurodegenerative disorder, affecting >20 % of older horses. There is a need for improved endocrine tests for early disease detection, and the thyrotropin-releasing hormone (TRH) stimulation test has been recommended for diagnosis of early or mild cases. However, it is currently not recommended for year-round use due to marked seasonal variability. The aims of this cohort study were to evaluate effects of month and season on adrenocorticotropic hormone (ACTH) responses to TRH stimulation and to derive monthly cut-offs for PPID d...
Blood-Based Markers for Skeletal and Cardiac Muscle Function in Eventing Horses before and after Cross-Country Rides and How They Are Influenced by Plasma Volume Shift.
Animals : an open access journal from MDPI    October 5, 2023   Volume 13, Issue 19 3110 doi: 10.3390/ani13193110
Giers J, Bartel A, Kirsch K, Müller SF, Horstmann S, Gehlen H.Horses competing in cross-country tests are subjected to high physical demands. Within the scope of this prospective longitudinal study, blood values of 20 elite eventing horses were examined before and after two- to four-star cross-country rides. The aim was to find out whether blood-based markers for skeletal muscle and cardiac muscle function change after cross-country exercise. Parameters that provide information about fluid balance, muscle enzymes, metabolites and cardiac muscle-specific markers were investigated. We developed an approach to eliminate the concentration changes caused by r...