Metabolic health in horses refers to the physiological processes that manage energy production, utilization, and storage in equine bodies. These processes are critical for maintaining overall health, performance, and well-being. Metabolic health encompasses various aspects, including glucose metabolism, insulin sensitivity, and lipid regulation. Conditions such as Equine Metabolic Syndrome (EMS) and insulin dysregulation are common metabolic disorders that affect horses, impacting their ability to process and store energy efficiently. This topic compiles peer-reviewed research studies and scholarly articles that explore the mechanisms, diagnostic approaches, and management strategies related to metabolic health in horses.
Park T, Cheong H, Yoon J, Kim A, Yun Y, Unno T.(1) Background: The intestinal microbiota plays an essential role in maintaining the host's health. Dysbiosis of the equine hindgut microbiota can alter the fermentation patterns and cause metabolic disorders. (2) Methods: This study compared the fecal microbiota composition of horses with intestinal disease and their healthy counterparts living in Korea using 16S rRNA sequencing from fecal samples. A total of 52 fecal samples were collected and divided into three groups: horses with large intestinal disease (n = 20), horses with small intestinal disease (n = 8), and healthy horses (n = 24). (...
Kalantari RK, Rouzbehan Y, Fazaeli H, Direkvandi E, Salem AZM.The aim of this study was to investigate, the effect of different levels of concentrates and grain processing on feeding behavior, nutrient digestibility, fecal pH and blood metabolites in the horse. Sixteen 5 to 11 years old Turkmen horses with an initial body weight 433±50 kg were used in this experiment based on completely randomized design. Four treatments were studied, in three treatments were used 20, 25 and 30% of concentrate containing processed grains (A20, A25 and A30, respectively), and in one treatment was used 25% of concentrate containing whole grain (B25). The amount of feed in...
Duarte PC, Ribeiro RM, Machado ART, Faleiros RR, Pimenta LPS, Filho JDS.The incidence of equine metabolic syndrome, a condition that results in endocrinopathic laminitis, is increasing worldwide. Although it is well known that the development of this syndrome depends on imbalances in energy metabolism and genetic traits, its pathophysiology remains unclear. Hydrogen nuclear magnetic resonance (H NMR) is a powerful tool used to compare metabolic profiles and to discriminate metabolites in living beings. The aim was to apply this technology to detect blood biomarkers candidates in horses that were previously demonstrated to developed metabolic changes when subjected...
Dunkel B, Knowles EJ, Chang YM, Menzies-Gow NJ.Blood l-lactate concentrations are higher in people with developing or established diabetes mellitus and insulin resistance. Objective: To investigate whether blood l-lactate concentrations are positively correlated with measures of insulin dysregulation (ID) or increased autumnal ACTH concentrations in ponies. Methods: Systemically healthy client-owned ponies (n = 101). Methods: Prospective case-control study. Blood samples were obtained from 101 clinically healthy ponies. Breed, weight, height, and subjective and objective measures of body condition were recorded. Blood l-lactate, glucose, t...
Ohmura H, Mukai K, Takahashi Y, Takahashi T.Thoroughbreds have high maximal oxygen consumption and show hypoxemia and hypercapnia during intense exercise, suggesting that the peripheral environment in skeletal muscle may be severe. Changes in metabolites following extreme alterations in the muscle environment in horses after exercise may provide useful evidence. We compared the muscle metabolites before and after supramaximal exercise to fatigue in horses. Six well-trained horses ran until exhaustion in incremental exercise tests. Biopsy samples were obtained from the gluteus medius muscle before and immediately after exercise for capil...
Tatum RC, McGowan CM, Ireland JL.Measurement of basal adrenocorticotrophic hormone (ACTH) is currently used to diagnose pituitary pars intermedia dysfunction (PPID) in horses, yet a systematic review of the evidence for its use has not been undertaken. This study aimed to systematically review evidence regarding the sensitivity and specificity of the basal ACTH diagnostic test. Electronic databases were systematically searched in January 2019, September 2020 and January 2021, for English language publications published prior to these dates. Screening, data extraction and quality assessment of publications was undertaken by th...
de Meeûs d'Argenteuil C, Boshuizen B, Oosterlinck M, van de Winkel D, De Spiegelaere W, de Bruijn CM, Goethals K, Vanderperren K, Delesalle CJG.Equine bioenergetics have predominantly been studied focusing on glycogen and fatty acids. Combining omics with conventional techniques allows for an integrative approach to broadly explore and identify important biomolecules. Friesian horses were aquatrained (n = 5) or dry treadmill trained (n = 7) (8 weeks) and monitored for: evolution of muscle diameter in response to aquatraining and dry treadmill training, fiber type composition and fiber cross-sectional area of the M. pectoralis, M. vastus lateralis and M. semitendinosus and untargeted metabolomics of the M. pectoralis and M. vastus late...
Boshuizen B, Moreno de Vega CV, De Maré L, de Meeûs C, de Oliveira JE, Hosotani G, Gansemans Y, Deforce D, Van Nieuwerburgh F, Delesalle C.Aleurone, a layer of the bran fraction, is deemed to be responsible for the positive health effects associated with the consumption of whole-grain products. Studies on rodents, pigs, and humans report beneficial effects of aleurone in five main areas: the reduction of oxidative stress, immunomodulatory effects, modulation of energy management, digestive health, and the storage of vitamins and minerals. Our study is the first aleurone supplementation study performed in horses. The aim of this study was to investigate the effect of an increase in the dose levels of aleurone on the postprandial g...
Shepherd M, Harris P, Martinson KL.Equine obesity is common, reducing quality of life and requiring dietary energy restriction. Equine obesity is identified using subjective body condition scoring. Considerations are given for life stage and health status when managing obese equines. Every effort should be made to maximize feeding duration, and minimize time spent without feed while meeting all essential nutrient requirements. Limiting total daily dry matter intake to 2% of current bodyweight per day of a low caloric, forage-based diet may result in adequate body weight loss. Weight loss and weight management plans should be mo...
Hesta M, Costa M.Many horses are fed differently than their wild ancestors. They often have limited access to pasture and are fed conserved forage and concentrates rich in starch and sugars, in only 2 meals per day. Feeding practices in contrast to natural feeding behavior can lead to gastrointestinal issues. Standard nutritional evaluation is warranted because of its important role in prevention and in treatment and management of diseases. When medical and nutritional treatments are combined, success rates are higher. New techniques to characterize equine microbiota have been used, allowing for microbiota man...
Hesta M, Shepherd M.Inappropriate nutrition is a priority welfare challenge. Nutritional mistakes are common and can lead to adverse events, such as poor growth and performance, colic, laminitis, and obesity. A detailed nutritional assessment involving evaluating the equine patient, current diet/ration, and management is essential in creating an effective nutritional plan. Goal(s) should be established and used to inform the plan. Management or resource barriers should be considered. Effective communication and a team-based approach versus an authoritarian one are likely to enhance the success of the nutritional ...
Stokes SM, Stefanovski D, Bertin FR, Medina-Torres CE, Belknap JK, van Eps AW.Endocrinopathic laminitis develops in association with insulin dysregulation, but the role of insulin in the pathogenesis remains unclear. Hyperinsulinemia can cause hypoaminoacidemia, which is associated with integumentary lesions in other species and therefore warrants investigation as a potential mechanism in laminitis. Objective: Evaluate plasma amino acid concentrations in the euglycemic-hyperinsulinemic clamp (EHC) and prolonged glucose infusion (PGI) laminitis models. Methods: Sixteen Standardbred horses. Methods: Prospective experimental study. Plasma amino acid concentrations were mea...
Mann S, Ramsay JD, Wakshlag JJ, Stokol T, Reed S, Divers TJ.High-serum γ-Glutamyl Transferase (GGT) activity has been associated with and thought to be a marker of maladaptation to training and possibly poor performance in racehorses, but the cause is unknown. Objective: To investigate possible metabolic and infectious causes for the high GGT syndrome. Methods: Pilot case-control study and nested case-control study. Methods: The case-control study in 2017 included 16 horses (8 cases and 8 controls with median [range] serum GGT 82 [74-148] and 22 [19-28] IU/L, respectively) from the same stable. In 2018, similar testing was performed in a nested case-...
Borba LA, Nogueira CEW, Bruhn FRP, da Silva GC, Feijó LS, Canisso IF, Curcio BDR.Neonatal sepsis is a leading cause of neonatal death during the first-week postfoaling. Despite recent advancements in the diagnosis and treatment of sepsis in the newborn foal, the non-specific clinical signs and subtle nature of this disease may result in delayed diagnosis until severe progression of the disease; thus, early detection of sepsis remains critical for a favourable outcome. This study aimed to identify early blood markers as predictive of sepsis on foals. Thirty-five foals were allocated into three groups: healthy control foals (n=7) and foals born from mares with placentitis: s...
Vervuert I, Stratton-Phelps M.Equine nutraceuticals are promoted as useful therapies to help optimize health and athletic performance, often without the benefit of independent research to support product efficacy and safety. This review focuses on 4 main categories of equine supplements that are frequently used as nutraceuticals: (i) supplements to support metabolic health, (ii) gastric support products, (iii) common ingredients that are included in supplements designed to support hoof health, and (iv) supplements to support joint health.
Lindåse S, Nostell K, Bergsten P, Forslund A, Bröjer J.Proxies are mathematical calculations based on fasting glucose and/or insulin concentrations developed to allow prediction of insulin sensitivity (IS) and β-cell response. These proxies have not been evaluated in horses with insulin dysregulation. The first objective of this study was to evaluate how fasting insulin (FI) and proxies for IS (1/Insulin, reciprocal of the square root of insulin (RISQI) and the quantitative insulin sensitivity check index (QUICKI)) and β-cell response (the modified insulin-to-glucose ratio (MIRG) and the homeostatic model assessment of β-cell function (HOMA-β)...
Bradbery AN, Coverdale JA, Hartz CJ, Millican AA, Goehring MS, Fikes KK, Picking E, Hammer CJ, Dunlap KA, Cardoso RC, Wickersham TA, Leatherwood JL....Results from previous studies indicate that maternal overnutrition during late gestation predisposes foals to metabolic disease, however, specific mechanisms resulting in disease remain unknown. Quarter Horse mares (n = 16), were randomly assigned to dietary treatments, beginning on gestational day 235, and consisted of a control group (CON- diet meeting nutrient requirement; n = 8) or an overfed diet (HIGH; n = 8) where mares received an additional 40 % above CON. On gestational days 285 and 315, an intravenous glucose tolerance test (FSIGTT) was conducted. Following parturition, foals were s...
Favro G, Habib H, Gennity I, Puschner B, Hales EN, Finno CJ, Moeller BC.Equine neuroaxonal dystrophy/degenerative myeloencephalopathy (eNAD/EDM) is a hereditary, deteriorating central nervous disease in horses. Currently, the only way to confirm eNAD/EDM is through a postmortem histological evaluation of the central nervous system. Vitamin E, specifically the isoform alpha-tocopherol (α-TP), is known to protect eNAD/EDM susceptible horses from developing the clinical phenotype. While vitamin E is an essential nutrient in the diet of horses, there are no diagnostic tests able to quantitate vitamin E and its metabolites in urine. An ultra-performance liquid chromat...
Mikhail E, Siccardi E, Bawazir A, Rajesh A, Prathyush S, Al Wazani DMK, Sabeek M, John T.IOX-2 is a potent inhibitor of enzyme prolyl hydroxylases-2 (PHD) that plays a critical role in regulating hypoxia inducible factor (HIF) abundance and oxygen homeostasis. Federation for Equestrian Sports has listed HIF activators as prohibited substances to prevent their usage in doping. Consequently, it became essential to develop adequate knowledge and testing methods to detect it in equine sports drug testing samples. The validated method utilizes ultra-high-performance liquid chromatography coupled to high-resolution mass spectrometry in order to detect extremely low concentration of the ...
Catandi GD, Obeidat YM, Broeckling CD, Chen TW, Chicco AJ, Carnevale EM.Advanced maternal age is associated with a decline in fertility and oocyte quality. We used novel metabolic microsensors to assess effects of mare age on single oocyte and embryo metabolic function, which has not yet been similarly investigated in mammalian species. We hypothesized that equine maternal aging affects the metabolic function of oocytes and in vitro-produced early embryos, oocyte mitochondrial DNA (mtDNA) copy number, and relative abundance of metabolites involved in energy metabolism in oocytes and cumulus cells. Samples were collected from preovulatory follicles from young (≤1...
Ribeiro RM, Ribeiro DS, Cota LO, Leme FO, M Carvalho A, Faleiros RR.This study aimed to characterize and correlate physiological and metabolic changes in horses fed a hypercaloric diet (HD). Nine mature horses with a mean initial body condition score of 2.9 ± 1 (scale, 1-9) were fed a high-calorie diet for 5 months. Fasting blood samples were collected before the study and biweekly for the duration of the project to determine the concentrations of cholesterol (CHOL), very low (VLDL), low (LDL) and high-density (HDL) lipoproteins, triglycerides, non-esterified fatty acids, and fructosamine. A low-dose oral glucose tolerance test (LGTT) was conducted before, 75...
Bourebaba L, Kornicka-Garbowska K, Al Naem M, Röcken M, Łyczko J, Marycz K.Protein tyrosine phosphatase 1B (PTP1B) is one of the major negative regulators of leptin and insulin signaling, and has been strongly implicated in insulin resistance development in the course of obesity and metabolic syndrome conditions; however, its exact role in controlling adipose tissue biogenesis is still poorly understood. This investigation aimed to elucidate whether selective inhibition of PTP1B using MSI-1436 compound may improve and restore the defective adipogenicity of ASCs isolated from EMS-affected horses. Equine ASC EMS cells were cultured under adipogenic conditions in the pr...
Halama A, Oliveira JM, Filho SA, Qasim M, Achkar IW, Johnson S, Suhre K, Vinardell T.Equine performance in endurance racing depends on the interplay between physiological and metabolic processes. However, there is currently no parameter for estimating the readiness of animals for competition. Our objectives were to provide an in-depth characterization of metabolic consequences of endurance racing and to establish a metabolic performance profile for those animals. We monitored metabolite composition, using a broad non-targeted metabolomics approach, in blood plasma samples from 47 Arabian horses participating in endurance races. The samples were collected before and after the c...
Delarocque J, Frers F, Huber K, Jung K, Feige K, Warnken T.Insulin dysregulation (ID) is an equine endocrine disorder, which is often accompanied by obesity and various metabolic perturbations. The relationship between weight variations and fluctuations of the insulin response to oral glucose tests (OGT) as well as the metabolic impact of ID have been described previously. The present study seeks to characterize the concomitant metabolic impact of variations in the insulin response and bodyweight during repeated OGTs using a metabolomics approach. Methods: Nineteen Icelandic horses were subjected to five OGTs over one year and their bodyweight, insuli...
Delarocque J, Reiche DB, Meier AD, Warnken T, Feige K, Sillence MN.Insulin dysregulation (ID) is a key risk factor for equine endocrinopathic laminitis, but in many cases ID can only be assessed accurately using dynamic tests. The identification of other biomarkers could provide an alternative or adjunct diagnostic method, to allow early intervention before laminitis develops. The present study characterised the metabolome of ponies with varying degrees of ID using basal and postprandial plasma samples obtained during a previous study, which examined the predictive power of blood insulin levels for the development of laminitis, in ponies fed a high-sugar diet...
Box JR, Karikoski NP, Tanskanen HE, Raekallio MR.Alpha-2-adrenoceptor agonists are sedatives that can cause fluctuations in serum insulin and blood glucose (BG) concentrations in horses. The objectives of this study were to investigate the effects of detomidine and vatinoxan on BG, insulin, and glucagon concentrations in horses with and without insulin dysregulation (ID). In a blinded cross-over design, eight horses with ID and eight horses without ID were assigned to each of four treatments: detomidine (0.02 mg/kg; DET), vatinoxan (0.2 mg/kg; VAT), detomidine + vatinoxan (DET + VAT), and saline control (SAL). Blood samples were taken at 0, ...
Bourdon B, Contentin R, Cassé F, Maspimby C, Oddoux S, Noël A, Legendre F, Gruchy N, Galéra P.Articular cartilage experiences mechanical constraints leading to chondral defects that inevitably evolve into osteoarthritis (OA), because cartilage has poor intrinsic repair capacity. Although OA is an incurable degenerative disease, several dietary supplements may help improve OA outcomes. In this study, we investigated the effects of Dielen® hydrolyzed fish collagens from skin (Promerim®30 and Promerim®60) and cartilage (Promerim®40) to analyze the phenotype and metabolism of equine articular chondrocytes (eACs) cultured as organoids. Here, our findings demonstrated the absence of cyto...
Current drug metabolismDecember 19, 2020
Volume 22, Issue 3 215-223 doi: 10.2174/1389200221666201217141025
Hu SX, Ernst K, Benner CP, Feenstra KL.Pharmacokinetic and pharmacodynamic assessment of ester-containing drugs can be impacted by hydrolysis of the drugs in plasma samples post blood collection. The impact is different in the plasma of different species. Objective: This study evaluated the stability of a prodrug, ketoprofen methylester (KME), in commercially purchased and freshly collected plasma of mouse, rat, dog, cat, pig, sheep, cattle and horse. Methods: KME hydrolysis was determined following its incubation in commercially purchased and freshly collected plasma of those species. Different esterase inhibitors were evaluated f...
Herbert E, Ouerdane H, Lecoeur P, Bels V, Goupil C.Muscles are biological actuators extensively studied in the frame of Hill's classic empirical model as isolated biomechanical entities, which hardly applies to a living organism subjected to physiological and environmental constraints. Here we elucidate the overarching principle of a living muscle action for locomotion, considering it from the thermodynamic viewpoint as an assembly of actuators (muscle units) connected in parallel, operating via chemical-to-mechanical energy conversion under mixed (potential and flux) boundary conditions. Introducing the energy cost of effort as the generaliza...
Salcedo-Jiménez R, Koenig JB, Lee OJ, Gibson TWG, Madan P, Koch TG.Extracorporeal shock wave therapy (ESWT) has been shown to induce different biological effects on a variety of cells, including regulation and stimulation of their function and metabolism. ESWT can promote different biological responses such as proliferation, migration, and regenerations of cells. Recent studies have shown that mesenchymal stromal cells (MSCs) secrete factors that enhance the regeneration of tissues, stimulate proliferation and differentiation of cells, and decrease inflammatory and immune reactions. Clinically, the combination of these two therapies has been used as a treatme...
de Laat MA, Reiche DB, Sillence MN, McGree JM.Endocrinopathic laminitis is common in horses and ponies, but the recurrence rate of the disease is poorly defined. Objective: To determine the incidence of, and risk factors for, the recurrence of endocrinopathic laminitis. Methods: Privately owned horses and ponies with acute laminitis (n = 317, of which 276 cases with endocrinopathic laminitis were followed up to study completion). Methods: This prospective cohort study collected data on veterinary-diagnosed cases of acute laminitis for 2 years. Each case was classified on acceptance to the study as endocrinopathic or non-endocrinopathi...
Cappelli K, Capomaccio S, Viglino A, Silvestrelli M, Beccati F, Moscati L, Chiaradia E.Endurance exercise induces metabolic adaptations and has recently been reported associated with the modulation of a particular class of small noncoding RNAs, microRNAs, that act as post-transcriptional regulators of gene expression. Released into body fluids, they termed circulating miRNAs, and they have been recognized as more effective and accurate biomarkers than classical serum markers. This study examined serum profile of miRNAs through massive parallel sequencing in response to prolonged endurance exercise in samples obtained from four competitive Arabian horses before and 2 h after the ...
Treiber K, Carter R, Gay L, Williams C, Geor R.Inflammatory and redox signals could render lamellar tissue susceptible to damage and contribute to higher risk for laminitis in obese or insulin resistant ponies just as these factors contribute to health risks in humans with metabolic syndrome. This study evaluated circulating markers of inflammatory and redox status in ponies that had a history of recurrent bouts of pasture-associated laminitis (PL, n = 42) or had never developed clinical laminitis (NL, n = 34) under the current management conditions. There were no differences (P > 0.05) between PL and NL ponies for markers of antioxidan...
Morgan RA, Keen JA, Walker BR, Hadoke PW.Endocrinopathic laminitis (EL) is a vascular condition of the equine hoof resulting in severe lameness with both welfare and economic implications. EL occurs in association with equine metabolic syndrome and equine Cushing's disease. Vascular dysfunction, most commonly due to endothelial dysfunction, is associated with cardiovascular risk in people with metabolic syndrome and Cushing's syndrome. We tested the hypothesis that horses with EL have vascular, specifically endothelial, dysfunction. Healthy horses (n = 6) and horses with EL (n = 6) destined for euthanasia were recruited. We studied v...
Pratt SE, Geor RJ, McCutcheon LJ.There is evidence that adaptation to diets rich in nonstructural carbohydrates (NSC) contributes to the development of insulin resistance in horses. To date, however, no study in horses has examined the effects of physical conditioning on diet-associated alterations in insulin sensitivity and glucose tolerance. Objective: To examine the effects of adaptation to concentrate feeds rich in NSC or fat on insulin sensitivity and glucose tolerance in horses, both in the sedentary state and after a subsequent period of physical conditioning. Methods: Fourteen mature Standardbred horses underwent both...
Tóth F, Frank N, Martin-Jiménez T, Elliott SB, Geor RJ, Boston RC.Hyperinsulinaemia is detected in horses with insulin resistance (IR) and has previously been attributed to increased pancreatic insulin secretion. Connecting peptide (C-peptide) can be measured to assess pancreatic function because it is secreted in equimolar amounts with insulin and does not undergo hepatic clearance. Objective: A human double antibody radioimmunoassay (RIA) detects C-peptide in equine serum and concentrations would reflect responses to different stimuli and conditions. Methods: A validation procedure was performed to assess the RIA. Six mature mares were selected and somatos...
Thomas DP, Fregin GF.The purpose of this study was to measure cardiovascular, respiratory, and metabolic responses to graded treadmill exercise in the horse. A five-stage treadmill test up to 90% of predicted maximal heart rate was administered to five sedentary horses. The highest measured level of exercise produced a sixfold increase in cardiac output and a 41% elevation of stroke volume over standing values. Left ventricular, arterial, and right atrial pressures as well as the maximal time derivative of left ventricular pressure were all elevated during exercise. Under the same two conditions hematocrit (Hct) i...
Gim JA, Hong CP, Kim DS, Moon JW, Choi Y, Eo J, Kwon YJ, Lee JR, Jung YD, Bae JH, Choi BH, Ko J, Song S, Ahn K, Ha HS, Yang YM, Lee HK, Park KD....Athletic performance is an important criteria used for the selection of superior horses. However, little is known about exercise-related epigenetic processes in the horse. DNA methylation is a key mechanism for regulating gene expression in response to environmental changes. We carried out comparative genomic analysis of genome-wide DNA methylation profiles in the blood samples of two different thoroughbred horses before and after exercise by methylated-DNA immunoprecipitation sequencing (MeDIP-Seq). Differentially methylated regions (DMRs) in the pre-and post-exercise blood samples of superio...
Zhu C, Faillace V, Laus F, Bazzano M, Laghi L.Metabolomics has been recognized as a powerful approach for disease screening. In order to highlight potential health issues in subjects, a key factor is the possibility to compare quantitatively the metabolome of their biofluids with reference values from healthy individuals. Such efforts towards the systematic characterization of the metabolome of biofluids in perfect health conditions, far from concluded for humans, have barely begun on horses. The present work attempts, for the first time, to give reference quantitative values for the molecules mostly represented in the urine metabolome of...
Haritou SJ, Zylstra R, Ralli C, Turner S, Tortonese DJ.Equine pituitary pars intermedia dysfunction (PPID) is a common and serious condition that gives rise to Cushing's disease. In the older horse, it results in hyperadrenocorticism and disrupted energy metabolism, the severity of which varies with the time of year. To gain insight into the mechanism of its pathogenesis, 24-h profiles for peripheral plasma melatonin, serotonin, dopamine and cortisol concentrations were determined at the winter and summer solstices, and the autumn and spring equinoxes in six horses diagnosed with Cushing's disease and six matched controls. The nocturnal rises in p...
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 ...
Burns TA, Watts MR, Weber PS, McCutcheon LJ, Geor RJ, Belknap JK.Hyperinsulinaemia has been implicated in the pathogenesis of laminitis; however, laminar cell types responding to insulin remain poorly characterised. Objective: To identify laminar cell types expressing insulin receptor (IRc) and/or insulin-like growth factor-1 receptor (IGF-1R); and to evaluate the effect of dietary nonstructural carbohydrate (NSC) on their expression. Methods: Mixed-breed ponies (n = 22) received a conditioning hay chop diet (NSC ∼6%); following acclimation, ponies were stratified into lean (n = 11, body condition score [BCS]≤4) or obese (n = 11, BCS ≥7) groups and ea...
Lewis SL, Holl HM, Streeter C, Posbergh C, Schanbacher BJ, Place NJ, Mallicote MF, Long MT, Brooks SA.Equine obesity can cause life-threatening secondary chronic conditions, similar to those in humans and other animal species. Equine metabolic syndrome (EMS), primarily characterized by hyperinsulinemia, is often present in obese horses and ponies. Due to clinical similarities to conditions such as pituitary pars intermedia dysfunction (formerly equine Cushing's disease), conclusive diagnosis of EMS often proves challenging. Aside from changes in diet and exercise, few targeted treatments are available for EMS, emphasizing the need for early identification of at-risk individuals to enable imple...
Wooldridge AA, Edwards HG, Plaisance EP, Applegate R, Taylor DR, Taintor J, Zhong Q, Judd RL.To characterize adiponectin protein complexes in lean and obese horses. Methods: 26 lean horses and 18 obese horses. Procedures-Body condition score (BCS) and serum insulin activity were measured for each horse. Denaturing and native western blot analyses were used to evaluate adiponectin complexes in serum. A human ELISA kit was validated and used to quantify high-molecular weight (HMW) complexes. Correlations between variables were made, and HMW values were compared between groups. Results: Adiponectin was present as a multimer consisting of HMW (> 720-kDa), low-molecular weight (180-kDa)...
Mularczyk M, Bourebaba N, Marycz K, Bourebaba L.Astaxanthin is gaining recognition as a natural bioactive component. This study aimed to test whether astaxanthin could protect adipose-derived stromal stem cells (ASCs) from apoptosis, mitochondrial dysfunction and oxidative stress. was used to extract astaxanthin, whose biocompatibility was tested after 24, 48 and 72 h of incubation with the cells; no harmful impact was found. ASCs were treated with optimal concentrations of astaxanthin. Several parameters were examined: cell viability, apoptosis, reactive oxygen levels, mitochondrial dynamics and metabolism, superoxide dismutase activity, ...
Swyers KL, Burk AO, Hartsock TG, Ungerfeld EM, Shelton JL.A study was conducted to determine whether direct-fed microbials (DFM) could be used to increase digestibility and minimize the risk of acidosis associated with feeding an increase in the amount of starch fed to horses. Fifteen mature Thoroughbred geldings were randomly assigned to 1 of 3 treatments in a 3 x 3 Latin square design balanced for carryover effects. Within each 26-d period, horses were offered grass hay + low-starch concentrate (LS; 1.2 g of starch x kg of BW(-1) x meal(-1)) from d 1 to 13 and then were abruptly changed to hay + high-starch concentrate (HS; 2.4 g of starch.kg of BW...
Stewart-Hunt L, Geor RJ, McCutcheon LJ.Increased insulin sensitivity occurs after a period of exercise training, but the mechanisms underlying this training-associated increase in insulin action have not been investigated. Objective: To examine the effects of short-term endurance training (7 consecutive days) and a subsequent period of inactivity (5 days) on whole body insulin sensitivity and GLUT-4 protein and the activities of glycogen synthase (GS) and hexokinase (HK) in skeletal muscle. It was hypothesised that training would increase insulin sensitivity in association with increased GLUT-4 protein and activities of GS and HK, ...
Fortier LA, Kornatowski MA, Mohammed HO, Jordan MT, O'Cain LC, Stevens WB.Structural changes in articular cartilage associated with the ageing process require definition for investigators performing developmental and age-related studies, for which information is lacking. Objective: To 1) determine the onset and end of puberty as defined by serum insulin like growth factor (IGF-I) and IGF-binding protein-3 (IGFBP-3) concentrations and 2) correlate articular-epiphyseal cartilage complex structural changes with the onset and end of puberty. Methods: IGF-I and IGFBP-3 were measured in serum samples from normal female and male horses age 9-715 days to determine peak and ...
Coleman MC, Belknap JK, Eades SC, Galantino-Homer HL, Hunt RJ, Geor RJ, McCue ME, McIlwraith CW, Moore RM, Peroni JF, Townsend HG, White NA....OBJECTIVE To investigate risk factors for the development of pasture- and endocrinopathy-associated laminitis (PEAL) in horses and ponies in North America. DESIGN Case-control study. ANIMALS 199 horses with incident cases of PEAL and 351 horses from 2 control populations (healthy horses [n = 198] and horses with lameness not caused by laminitis [153]) that were evaluated in North America between January 2012 and December 2015 by veterinarian members of the American Association of Equine Practitioners. PROCEDURES North American members of the American Association of Equine Practitioners were co...
Schott HC, Marlin DJ, Geor RJ, Holbrook TC, Deaton CM, Vincent T, Dacre K, Schroter RC, Jose-Cunilleras E, Cornelisse CJ.Limited information exists about the physiological changes and clinical problems that occur in elite horses competing in high-speed 160 km endurance races. Objective: To provide initial data describing changes in physiological and laboratory measurements in horses competing in a high-speed, 160 km endurance race under temperate conditions and to compare data between horses that successfully completed the race and those that failed to finish. Methods: Body mass (BM) was measured, blood samples were collected, and veterinary examinations performed on horses before, during, and at the finish of a...
Luo J, Wang Z, Tang C, Yin Z, Huang J, Ruan D, Fei Y, Wang C, Mo X, Li J, Zhang J, Fang C, Li J, Chen X, Shen W.Tendinopathy is a common motor system disease that leads to pain and reduced function. Despite its prevalence, our mechanistic understanding is incomplete, leading to limited efficacy of treatment options. Animal models contribute significantly to our understanding of tendinopathy and some therapeutic options. However, the inadequacies of animal models are also evident, largely due to differences in anatomical structure and the complexity of human tendinopathy. Different animal models reproduce different aspects of human tendinopathy and are therefore suitable for different scenarios. This rev...
Kenéz Á, Warnken T, Feige K, Huber K.Insulin dysregulation in horses is a metabolic condition defined by high insulin concentrations in the blood and peripheral insulin resistance. This hyperinsulinemia is often associated with severe damage in the hooves, resulting in laminitis. However, we currently lack detailed information regarding the potential involvement of particular metabolic pathways in pathophysiological causes and consequences of equine insulin dysregulation. This study aimed to assess the dynamic metabolic responses given to an oral glucose test (OGT) in insulin-sensitive and insulin-dysregulated horses by a targete...
Gondim FJ, Zoppi CC, Pereira-da-Silva L, de Macedo DV.Maximal blood lactate steady state concentration (MLSS) and anaerobic threshold (AT) have been shown to accurately predict long distance events performance and training loads, as well, in human athletes. Horse endurance races can take up to 160 km and, in practice, coaches use the 4 mM blood lactate concentration, a human based fixed concentration to establish AT, to predict training loads to horse athletes, what can lead to misleading training loads. The lactate minimum speed (LMS) protocol that consists in an initial elevation in blood lactate level by a high intensity bout of exercise and t...
Al Naem M, Bourebaba L, Kucharczyk K, Röcken M, Marycz K.Mesenchymal stromal cells (MSC) have become a popular treatment modality in equine orthopaedics. Regenerative therapies are especially interesting for pathologies like complicated tendinopathies of the distal limb, osteoarthritis, osteochondritis dissecans (OCD) and more recently metabolic disorders. Main sources for MSC harvesting in the horse are bone marrow, adipose tissue and umbilical cord blood. While the acquisition of umbilical cord blood is fairly easy and non-invasive, extraction of bone marrow and adipose tissue requires more invasive techniques. Characterization of the stem cells a...
Wallis N, Raffan E.Obesity is one of the most prevalent health conditions in humans and companion animals globally. It is associated with premature mortality, metabolic dysfunction, and multiple health conditions across species. Obesity is, therefore, of importance in the fields of medicine and veterinary medicine. The regulation of adiposity is a homeostatic process vulnerable to disruption by a multitude of genetic and environmental factors. It is well established that the heritability of obesity is high in humans and laboratory animals, with ample evidence that the same is true in companion animals. In this r...
Mann S, Ramsay JD, Wakshlag JJ, Stokol T, Reed S, Divers TJ.High-serum γ-Glutamyl Transferase (GGT) activity has been associated with and thought to be a marker of maladaptation to training and possibly poor performance in racehorses, but the cause is unknown. Objective: To investigate possible metabolic and infectious causes for the high GGT syndrome. Methods: Pilot case-control study and nested case-control study. Methods: The case-control study in 2017 included 16 horses (8 cases and 8 controls with median [range] serum GGT 82 [74-148] and 22 [19-28] IU/L, respectively) from the same stable. In 2018, similar testing was performed in a nested case-...
Pratt-Phillips SE, Geor RJ, McCutcheon LJ.To compare, in horses, estimates of insulin sensitivity obtained from minimal model analysis (MMA) of a frequently sampled IV glucose tolerance test (FSIGTT) with estimates from the euglycemic-hyperinsulinemic clamp (EHC) and to evaluate the validity of surrogate estimates of insulin sensitivity derived from an oral glucose tolerance test (OGTT). Methods: 18 mature Standardbreds (mean ± SD body weight, 428.9 ± 35.9 kg; mean ± SD body condition score, 4.4 ± 1.0 [on a scale of 1 to 9]). Methods: All horses underwent at least 2 of the 3 procedures (EHC [n = 15], insulin-modified FSIGTT [18], ...
Hamamoto-Hardman BD, Steffey EP, Weiner D, McKemie DS, Kass P, Knych HK.The objective of the current study was to describe and characterize the pharmacokinetics and selected pharmacodynamic effects of morphine and its two major metabolites in horses following several doses of morphine. A total of ten horses were administered a single intravenous dose of morphine: 0.05, 0.1, 0.2, or 0.5 mg/kg, or saline control. Blood samples were collected up to 72 hr, analyzed for morphine, and metabolites by LC/MS/MS, and pharmacokinetic parameters were determined. Step count, heart rate and rhythm, gastrointestinal borborygmi, fecal output, packed cell volume, and total prote...
