Topic:Metabolic Health
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.
Validity of an established metabolic disorder index as a predictor for metabolic eliminations in endurance horses. Endurance horses are usually eliminated from the race due to lameness, metabolic ailments or technical reasons. The purpose of the study was to determine the validity and reliability of the metabolic disorder index (MDI) in predicting metabolic eliminations in endurance horses during an endurance race. Fifty-four endurance horses competing on two local endurance tracks were involved in the study. Blood samples were collected a day prior to the event to determine packed cell volume (PCV), chloride (Cl), interleukin-6 (IL-6), creatine kinase (CK) and glutathione reductase (GR) concentrations fro...
Characterization of trotter horses urine metabolome by means of proton nuclear magnetic resonance spectroscopy. 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...
Case-control study of risk factors for pasture-and endocrinopathy-associated laminitis in North American horses. 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...
Use of principle component analysis to quantitatively score the equine metabolic syndrome phenotype in an Arabian horse population. Equine metabolic syndrome (EMS), like human metabolic syndrome, comprises a collection of clinical signs related to obesity, insulin dysregulation and susceptibility to secondary inflammatory disease. Although the secondary conditions resulting from EMS can be life-threatening, diagnosis is not straightforward and often complicated by the presence of other concurrent conditions like pituitary pars intermedia dysfunction (PPID). In order to better characterize EMS, we sought to describe the variation within, and correlations between, typical physical and endocrine parameters for EMS. Utilizing ...
Combination of resveratrol and 5-azacytydine improves osteogenesis of metabolic syndrome mesenchymal stem cells. Endocrine disorders have become more and more frequently diagnosed in humans and animals. In horses, equine metabolic syndrome (EMS) is characterized by insulin resistance, hyperleptinemia, hyperinsulinemia, inflammation and usually by pathological obesity. Due to an increased inflammatory response in the adipose tissue, cytophysiological properties of adipose derived stem cells (ASC) have been impaired, which strongly limits their therapeutic potential. Excessive accumulation of reactive oxygen species, mitochondria deterioration and accelerated ageing of those cells affect their multipotency...
Persistent hypoglycemia associated with lipid storage myopathy in a paint foal. A 12-hours-old Paint filly was examined because of weakness and dull mentation after birth. Despite IV administered dextrose, the foal remained persistently hypoglycemic with increase in serum activity of muscle and liver enzymes. A postmortem diagnosis of lipid myopathy most similar to multiple acyl-CoA dehydrogenase deficiency (MADD) was confirmed by findings of myofiber lipid accumulation, elevated urine organic acids, and serum free acylcarnitines with respect to control foals. This report details a case of equine neonatal lipid storage myopathy with many biochemical characteristics of MAD...
Sweet taste receptor inhibitors: Potential treatment for equine insulin dysregulation. Hyperinsulinemia is a major risk factor for equine laminitis, a debilitating and painful foot condition. Sweet taste receptor (T1R2/3) inhibitors have been used to reduce the insulin and glucose responses to oral carbohydrates in other species. However, their effect in horses has not been investigated. It would be useful to be able to attenuate the large post-prandial insulin response that typically occurs when a carbohydrate-rich meal is fed to insulin-dysregulated horses. Here we have determined the efficacy of two T1R2/3 inhibitors, lactisole and Gymnema sylvestre, for reducing glucose upta...
Alterations in Metabolic Status and Headshaking Behavior Following Intravenous Administration of Hypertonic Solutions in Horses with Trigeminal-Mediated Headshaking. Trigeminal-nerve-mediated headshaking represents a major welfare challenge for owners and veterinarians and is caused by a low threshold firing of the trigeminal nerve resulting in pain manifested as violent head jerking that often terminates the horse’s career and life due to poor quality of life and suffering. As metabolic changes such as acid⁻base status and electrolytes play a role in nerve firing, this study sought to assess the effects following administration of hypertonic solutions on headshaking behavior in affected horses. This prospective randomized controlled crossover desi...
Male Flat Jockeys Do Not Display Deteriorations in Bone Density or Resting Metabolic Rate in Accordance With Race Riding Experience: Implications for RED-S. Despite consistent reports of poor bone health in male jockeys, it is not yet known if this is a consequence of low energy availability or lack of an osteogenic stimulus. Given the rationale that low energy availability is a contributing factor in low bone health, we tested the hypothesis that both hip and lumbar bone mineral density (BMD) should progressively worsen in accordance with the years of riding. In a cross-sectional design, male apprentice (n = 17) and senior (n = 14) jockeys (matched for body mass and fat-free mass) were assessed for hip and lumbar spine BMD, as well as bot...
Association between hyperinsulinaemia and laminitis severity at the time of pituitary pars intermedia dysfunction diagnosis. Hyperinsulinaemia is the suspected component of insulin dysregulation having the strongest association with laminitis and occurs variably in equids with pituitary pars intermedia dysfunction (PPID). Objective: We hypothesised that magnitude of hyperinsulinaemia correlates with laminitis severity in PPID-affected equids. Furthermore, we hypothesised that owners can be unaware of chronic endocrinopathic laminitis. Methods: Cross-sectional study. Methods: Serum insulin concentrations, owner-reported laminitis history and radiographic evidence of laminitis were determined in 38 client-owned horses...
Using the indicator amino acid oxidation technique to study threonine requirements in horses receiving a predominantly forage diet. Threonine has been reported to be the second limiting amino acid in typical equine diets, but its actual requirement has not been determined in horses. To evaluate amino acid metabolism and requirements, the indicator amino acid oxidation (IAAO) method has been successfully used in other species. The objective of this research was to estimate threonine requirements in mature horses fed timothy hay and concentrate in 4:1 ratio using the IAAO method. Six Thoroughbred mares (579.9 ± 46.7 kg) received each of 6 levels of threonine intake, 41, 51, 61, 70, 80 and 89 mg/kg BW/day, in a randomly ...
Characterization of insulin and IGF-1 receptor binding in equine liver and lamellar tissue: implications for endocrinopathic laminitis. Although it is well established that equine laminitis can be triggered by extreme hyperinsulinemia, the mechanism of insulin action is not known. High concentrations of insulin lead to separation of the weight-bearing apparatus from the hoof wall and are associated with an increased cycle of cell death and proliferation in the lamellae. Gene expression and immunohistochemistry studies have indicated that the lamellae are sparsely populated with insulin receptors, whereas IGF-1 receptors (IGF-1R) are abundant, suggesting that the action of insulin may be mediated by insulin binding to the IGF-1...
Evaluation of Oxidative Stress and Mitophagy during Adipogenic Differentiation of Adipose-Derived Stem Cells Isolated from Equine Metabolic Syndrome (EMS) Horses. Mesenchymal stem cells (MSCs) are frequently used in both human and veterinary medicine because their unique properties, such as modulating the immune response and differentiating into multiple lineages, make them a valuable tool in cell-based therapies. However, many studies have indicated the age-, lifestyle-, and disease-related deterioration of MSC regenerative characteristics. However, it still needs to be elucidated how the patient's health status affects the effectiveness of MSC differentiation. In the present study, we isolated mesenchymal stem cells from adipose tissue (adipose-derive...
Glucose and Insulin Response of Horses Grazing Alfalfa, Perennial Cool-Season Grass, and Teff Across Seasons. Elevated nonstructural carbohydrate (NSC) values in pasture forages can cause adverse health effects in some horses (Equus caballus L.). The objectives of this study were to determine the impact of different forage species on blood glucose and insulin concentrations of horses throughout the grazing season. Research was conducted in July (summer) and September (fall) in St. Paul, MN. Alfalfa (Medicago sativa L.), mixed perennial cool-season grasses (CSG), and teff (Eragrostis tef [Zucc.] Trotter) pastures were grazed by six horses (24 ± 2 years) that were randomly assigned to one of three for...
Ex vivo effects of insulin on the structural integrity of equine digital lamellae. Laminitis has a considerable impact on the equine industry. Endocrinopathic laminitis is the most common form and affected horses often have hyperinsulinaemia due to an underlying metabolic disorder. Objective: The aim of this study was to determine if insulin weakens the structural integrity of digital lamellae and to develop an ex vivo model for the study of hyperinsulinaemia-induced lamellar failure. Methods: Ex vivo experiment. Methods: Biomechanical testing was used to assess the structural integrity of lamellar explants exposed to either medium alone (control) or medium supplemented with...
Plasma homocysteine concentrations in healthy horses and horses with atrial fibrillation. Homocysteine (HCY) is an amino acid produced from methionine metabolism. Plasma homocysteine concentrations ([HCY]p) are elevated (>13 μmol/L) in people with atrial fibrillation (AF) and can predict the recurrence of AF after cardioversion. This study aimed to validate a commercially available human HCY assay for use in horses to develop reference intervals for [HCY]p and compare [HCY]p in healthy horses and horses with AF. Methods: Healthy horses (n = 27) and horses with AF (n = 55, 34 of which were cardioverted using transvenous electrical cardioversion). Methods: Blood samples were a...
Endocrine Disorders of the Equine Athlete. Equine athletes are affected by 2 major endocrine/metabolic disorders, insulin dysregulation (ID) and pituitary pars intermedia dysfunction. ID is a risk factor for laminitis in horses, which poses the greatest threat to performance because of the damage that it causes to hoof structures. This article includes an in-depth discussion of ID and other risk factors for laminitis that are grouped together as equine metabolic syndrome. As horses age, the risk of pituitary pars intermedia dysfunction increases, and this endocrine disorder may exacerbate preexisting ID and further increase the risk of...
Validity and application of immunoturbidimetric and enzyme-linked immunosorbent assays for the measurement of adiponectin concentration in ponies. Circulating adiponectin concentrations were lower in ponies with a history of endocrinopathic laminitis and in nonlaminitic ponies that subsequently developed laminitis. The assays used in these studies have been discontinued or are no longer valid. Objective: (1) to determine the validity of immunoturbidimetric (IT) and enzyme linkedimmunosorbent (ELISA) assays for equine total and high molecular weight (HMW) [adiponectin] measurement and (2) to investigate the association between [adiponectin] measured using these assays and endocrinopathic laminitis. Methods: Method validation and cohort st...
Insulin dysregulation in horses with systemic inflammatory response syndrome. Systemic inflammation is a cause of insulin dysregulation in many species, but the insulin and glucose dynamics in adult horses diagnosed with systemic inflammatory response syndrome (SIRS) are poorly documented. Objective: In SIRS in horses, insulin and glucose dynamics will be altered and associated with survival. Methods: Adult horses diagnosed with SIRS admitted to a referral hospital. Methods: Prospective study enrolling horses diagnosed with SIRS in which serum insulin and glucose concentrations were measured. Horses were grouped by outcome (survival, hyperinsulinemia, and hyperglycemia)...
Intracellular free magnesium concentration in healthy horses. Equine metabolic syndrome (EMS) is a worldwide disease in horses that parallels human diabetes mellitus type 2. In both diseases, patients show an altered peripheral insulin sensitivity as a key feature. In humans, multiple studies have demonstrated the beneficial effect of magnesium supplementation on insulin sensitivity. However, serum magnesium levels vary and are therefore not a reliable indicator of the patients' magnesium status. Determining the intracellular free magnesium concentration appears to be a more sensitive diagnostic indicator. In this study, the free intracellular magnesium ...
Lower plasma trans-4-hydroxyproline and methionine sulfoxide levels are associated with insulin dysregulation in horses. 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...
Circulating miRNAs as Putative Biomarkers of Exercise Adaptation in Endurance Horses. 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 ...
Fédération Equestre Internationale endurance events: Risk factors for failure to qualify outcomes at the level of the horse, ride and rider (2010-2015). An epidemiological study of elite endurance riding was conducted using data from every Fédération Equestre Internationale (FEI) endurance event from 2010 to 2015, comprising 82,917 starts. The aim of the study was to identify risk factors associated with failure to qualify outcomes for horses during FEI endurance rides. The FEI endurance rules state that, during a ride, horses must be assessed by veterinarians several times, giving veterinarians the opportunity to prevent those horses exhibiting signs of lameness or metabolic problems from continuing further. Multivariable logistic regressio...
Insulinaemic and glycaemic responses to three forages in ponies. Reduction of the hyperinsulinaemic response to feeding is central to the management of insulin dysregulation (ID). The aim of this study was to compare insulinaemic and glycaemic responses to soaked hay, dry hay and haylage in ponies. Twelve ponies of mixed breeds were maintained under identical management conditions. A randomised four-way crossover trial was conducted, in which fasted animals were fed a meal of 0.25% body weight as dry matter intake soaked hay, dry hay or haylage, or administered an oral glucose test (OGT). Blood glucose and serum insulin concentrations were measured before a...
Glucagon-like peptide-2: A potential role in equine insulin dysregulation. Equine insulin dysregulation (ID) is a common and poorly understood disorder that increases the risk of laminitis. Recent data show that the condition may be associated with alteration of the enteroinsular axis and enhanced glucose bioavailability. Upregulation of glucagon-like peptide-2 (GLP-2), an intestinotrophic peptide, leads to enhanced nutrient uptake and metabolic dysfunction in other species. Objective: The study aimed to 1) determine whether GLP-2 is differentially expressed in insulin-dysregulated ponies, compared with healthy ponies, and 2) confirm intestinal expression of the GLP-...
Humoral and cell-mediated immune responses to influenza vaccination in equine metabolic syndrome (EMS) horses. Obesity is an increasing problem in the equine population with recent reports indicating that the percentage of overweight horses may range anywhere from 20.6-51%. Obesity in horses has been linked to more serious health concerns such as equine metabolic syndrome (EMS). EMS is a serious problem in the equine industry given its defining characteristics of insulin dysregualtion and obesity, as well as the involvement of laminitis. Little research however has been conducted to determine the effects of EMS on routine healthcare of these horses, in particular how they respond to vaccination. It has...
Metabolic perturbations in Welsh Ponies with insulin dysregulation, obesity, and laminitis. Metabolomics, the study of small-molecule metabolites, has increased understanding of human metabolic diseases, but has not been used to study equine metabolic syndrome (EMS). Objective: (1) To examine the serum metabolome of Welsh Ponies with and without insulin dysregulation before and during an oral sugar test (OST). (2) To identify differences in metabolites in ponies with insulin dysregulation, obesity, or history of laminitis. Methods: Twenty Welsh Ponies (mean ± SD; 13.8 ± 9.0 years) classified as non-insulin dysregulated [CON] (n = 10, insulin 60 mU/L) at 75 minutes ...
Effect of varying the dose of corn syrup on the insulin and glucose response to the oral sugar test. The oral sugar test (OST) is used to identify equine insulin dysregulation (ID); however only a dose of 0.15 mL/kg bwt corn syrup has been evaluated. Objective: To determine the effect of varying the dose of corn syrup on insulin and glucose response to the OST and the test's ability to distinguish between ponies with a history of laminitis (PL) and without laminitis (NL). Methods: Randomised crossover experiment. Methods: After an overnight fast, in a three-way randomised crossover study with a 7-day washout, 0.15, 0.3 or 0.45 mL/kg bwt corn syrup was administered orally to eight ponies (5 PL...
The pathology of vitamin D deficiency in domesticated animals: An evolutionary and comparative overview. Although vitamin D is critical to calcium/phosphorus homeostasis, bone formation and remodeling, there is evolution-based variation between species in vitamin D metabolism and susceptibility to rickets and osteomalacia. Most herbivores produce vitamin D3 in response to sunlight, but dogs and cats have generally lost the ability as carnivore diets are rich in vitamin D. Nutritional deficiencies and/or poor exposure to sunlight can induce rickets in birds, swine, cattle and sheep, but horses are less susceptible as they have evolved a calcium homeostasis that is quite different than other animal...
Effects of age and diet on glucose and insulin dynamics in the horse. Age and diet may affect insulin sensitivity (SI) but these factors have received limited investigation in horses. Objective: To measure minimal model parameters during an insulin-modified frequently sampled intravenous glucose tolerance test (FSIGTT) after adaptation to a forage only diet (HAY) or forage supplemented with either starch/sugar-rich (SS) or oil/fibre-rich (FF) concentrate feeds; and to assess glucose and insulin responses to a standardised meal challenge (SMC, 4 g/kg BW of SS) after diet adaptation in adult and aged mares. Methods: Latin square design with eight adult (5-12 yea...