Topic:Metabolism
Equine metabolism encompasses the biochemical processes that occur within horses to maintain life, including the conversion of food into energy, the synthesis of necessary compounds, and the elimination of waste products. These processes are essential for supporting various physiological functions such as growth, reproduction, and physical performance. Key components of equine metabolism include carbohydrate, fat, and protein metabolism, each of which contributes to the overall energy balance and health of the horse. Factors influencing metabolic rate and efficiency in horses include age, breed, diet, exercise, and health status. This page compiles peer-reviewed research studies and scholarly articles that explore the mechanisms, regulation, and implications of metabolic processes in equine physiology.
Blood and fecal metabolic responses of mature horses fed rhizoma peanut hay. Rhizoma peanut (RP, Arachis glabrata Benth) is an alternative legume forage to alfalfa (ALF, Medicago sativa L.) with less non-structural carbohydrates and crude protein. Yet, metabolic responses to consuming RP hay have never been evaluated in horses. Objective: The objective of this study was to investigate the effect of feeding RP 'Florigraze' hay on fecal and blood metabolic variables compared to alfalfa 'Legendary XHD' and bermudagrass (BMG, Cynodon dactylon L. 'Coastal') hays fed to maintenance horses. Methods: Six mature Quarter Horse geldings (596±40 kg) were randomly assigned to one ...
Differential profiles of GH, IGF-1, and fructosamine in follicular fluid and plasma of cyclic mares. Growth hormone (GH) influences follicular development mainly by stimulating insulin-like growth factor 1 (IGF-1), which acts systemically and locally within the ovary. However, the metabolic profile of follicular fluid (FF) in mares, particularly markers such as fructosamine (FRUCT), an indicator of glucose metabolism, remains poorly characterized. This study aimed to evaluate GH, IGF-1, and FRUCT concentrations in plasma and FF and their variation across follicle sizes. Sixty ovaries were collected during the breeding season from 30 clinically normal mares raised for meat production. Blood sa...
Nicotinic acid treatment improves the developmental potential of equine oocytes for cloned embryo production. Nicotinic acid (NA) treatment during in vitro maturation (IVM) has been shown to elevate nicotinamide adenine dinucleotide (NAD) levels and improve oocyte developmental competence. Suboptimal equine oocyte IVM systems currently limit the efficiency of viable embryo in vitro production. This study evaluated NA supplementation during IVM for cloned equine embryo production, using oocytes from abattoir-sourced ovaries and live mares via ovum pick-up (OPU). Abattoir-derived oocytes (n = 694) were treated without or with 50 or 200 μM NA during the 18 h holding period (Pre-IVM). Next, OPU-deriv...
Pancreatic islet remodeling in horses with hyperinsulinemia and pituitary dysfunction. The equine pancreas remains understudied, particularly in the context of endocrine disease. This study aimed to characterize regional islet distribution and composition in the normal equine pancreas and investigate how hyperinsulinemia (HI) and pituitary pars intermedia dysfunction (PPID) influence pancreatic islet morphology and hormone expression. In the first experiment, pancreas samples from eight healthy horses were collected and analyzed across three anatomical locations: left lobe, body, and right lobe. The left lobe exhibited a greater relative islet area and perimeter compared to the ...
Pharmacokinetics of Intragastric Ursodeoxycholic Acid and Its Impact on Bile Acid Profiles in Horses. Ursodeoxycholic acid (UDCA), a secondary bile acid (BA) with therapeutic applications, is standard therapy for cholestatic hepatopathies in humans. In recent years, its use has been increasingly explored in equine medicine for similar indications. Pharmacokinetic data for UDCA in horses are currently lacking. This study aimed to describe the pharmacokinetic parameters following a single intragastric administration of 15 mg/kg in nine healthy, fasted horses and to characterize the changes in their BA profiles. Plasma concentrations of UDCA were measured at specific time points using liquid ch...
Feed intake, digestibility and passage kinetics in grazing horses. Feed intake and digestibility are important indicators for sufficient nutrient supply, but they can be assessed only to a limited extent in horses on pasture. In horses, feed intake is embedded in a complex behavioural pattern of searching, selecting, chewing and almost constant movement called foraging. The objectives of this study were to estimate organic matter intake (OMI) and organic matter digestibility (OMD) in six horses, 24 h/day on pasture, based on plant alkanes and synthetic n-hexatriacontane (C) excretion. A multi-compartmental model was fitted to the marker excretion and the C m...
miRNAS and target genes are regulated post-training in quarter horse athletes. In the context of Brazilian equestrian sports, the Quarter Horse (QH) breed has the third largest population of registered horses and stands out for its numerous abilities in various disciplines. Studies on equine health and athletic performance parameters are scarce, especially involving molecular markers. Objective: This study aimed to investigate the differential expression of microRNAs and target genes involved in metabolic pathways of exercise and to assess hematological and clinical changes in 10 horses (Equus caballus Linnaeus) of the QH breed under different physiological conditions. H...
Evaluation of oxidative stress in the newborn foal: a multibiomarker approach. During the perinatal period, neonates experience a sudden increase in oxygen exposure, predisposing them to oxidative stress. Objective: This prospective, in vivo study aimed to evaluate biomarkers of oxidative stress and antioxidant defence in healthy neonatal foals during the first 48 hours of life. Methods: Ten Standardbred foals were enrolled. Blood samples were collected at birth, 24 hours, and 48 hours after birth and analyzed for biomarkers using spectrophotometry assays. Statistical analysis was performed using non-parametric tests and linear regression. Results: The results revealed s...
The Effect of Seasonal Changes in Non-Structural Carbohydrates in Pasture on the Metabolic Profile of Horses with Laminitis. This study aimed to examine the seasonal dynamics of non-structural carbohydrates in pasture and their relationship to metabolic indicators in horses with a history of laminitis. Thirty Hucul mares were divided into a laminitis group (LG, = 15) and a control group (CG, = 15). Insulin, glucose, fructosamines concentrations and body weight were monitored during four sampling periods (S0-S3), while pasture variables were analyzed during three periods (S1-S3). The concentration of water-soluble carbohydrates was highest in May (126.8 g/kg DM) and measured lower in October (57.9 g/kg DM), while s...
Affiliative behaviours regulate allostasis development and shape biobehavioural trajectories in horses. Social interactions shape both the physiological and behavioural development of offspring, and poor care/early caregiver loss is known to promote adverse outcomes during infancy in both animals and humans. How affiliative behaviours impact the future development of offspring remains an open question. Here, we used Equus caballus (domestic horse) as a model to investigate this question. By coupling magnetic resonance imaging, longitudinal biobehavioural assessments and advanced multivariate statistical modelling, we found that prolonged maternal presence during infancy promotes the maturation o...
Endurance exercise induces distinct skeletal and cardiac mitochondrial adaptations in racehorses. Mitochondrial respiration sustains the high energy demands of endurance exercise, yet the extent to which atrial, ventricular, and skeletal muscle mitochondria adapt remains uncertain. At the same time, endurance athletes face an increased risk of atrial fibrillation (AF), but the role of cardiac metabolism in arrhythmia susceptibility is poorly understood. Here, we compared mitochondrial respiration in skeletal muscle and across all four cardiac chambers between trained and untrained racehorses ( = 34) to investigate adaptations associated with long-term endurance exercise. We further examine...
Clinical and laboratory evaluation in horses submitted to intracecal fluid therapy administered in two different rates. Two routes of administration for electrolyte solutions are commonly used in horses with fluid, electrolyte, and acid-base imbalances: intravenous and nasogastric. Despite the frequent use of these routes, there are situations in which they cannot be applied. In such cases, intracecal fluid therapy represents a viable alternative, as this route enables the administration of enteral electrolyte solutions even in animals lacking normal anterior gastrointestinal function. This study aimed to evaluate the effects of a neutral hypotonic enteral electrolyte solution administered intracecally at two d...
The Effect of Training on the Expression of Protein and Metabolites in the Plasma Exosomes of the Yili Horse. The effects of physical exercise on protein expression and metabolites in the plasma exosomes of horses are not yet clear. This study aims to elucidate the effects of exercise training on the expression of plasma extracellular vesicle proteins and metabolites in horses through multi-omics analysis, providing reference indicators for the training and performance evaluation of horses. Methods: Eight healthy 3-year-old horses were selected for the study, with four untrained horses as the control group and four trained horses as the training group. After conducting proteomic and metabolomic an...
LMF1 frameshift deletion in Franches-Montagnes horses with hypertriglyceridemia-induced pancreatitis. Hypertriglyceridemia (HTG) may be inherited and caused by variants in genes encoding enzymes of lipid metabolism. This study was prompted by the observation of eight Franches-Montagnes (FM) foals showing elevated plasma triglyceride levels and episodes of fatal acute pancreatitis. We termed this phenotype hypertriglyceridemia-induced pancreatitis (HIP). The affected foals were distantly related and inbred to a prominent stallion suggesting autosomal recessive inheritance. Whole genome sequencing of an affected foal identified a homozygous loss of function variant in LMF1 encoding lipase matura...
Quantitative modeling reveals prolonged lactate clearance in young and unraced Jeju horses following high-intensity exercise under passive recovery conditions. To model lactate recovery kinetics in relation to sex, age, running speed, and racing experience, and to estimate blood lactate clearance time under passive recovery conditions that reflect current management practices in Jeju horses, a less well-characterized pony-sized indigenous breed. Unassigned: From October through December 2022, BLC was measured at baseline, 10 minutes after 800-m barrier trials (time [T]-1), and 50 minutes (T2) after 800-m barrier trials in 40 race-trained Jeju horses (2 to 4 years old). Lactate clearance was modeled using nonlinear regression with an exponential decay...
Canagliflozin: Pharmacokinetics, tolerability and glucose/insulin effects of supratherapeutic doses in healthy horses. Sodium-glucose co-transporter 2 inhibitors like canagliflozin (CFZ) have shown promise in preventing hyperinsulinemia-associated laminitis in horses, but data on pharmacokinetics, tolerability, and controlled studies are limited. This randomized, open-label, placebo-controlled, crossover study evaluated these aspects of CFZ treatment in eight healthy Standardbred mares. Each horse received single supratherapeutic oral doses of CFZ (1.8 mg/kg or 3.6 mg/kg) and placebo, with a two-week washout between treatments. A graded glucose infusion (GGI) was administered post-treatment to evaluate glu...
Plasma Activin A concentrations are not a useful biomarker for detecting insulin dysregulation and predicting laminitis risk in ponies. Circulating insulin concentrations are used to quantify risk of laminitis in currently non-laminitic ponies. Basal serum activin A (AA) concentration has previously been positively correlated with serum insulin concentrations 60 minutes (T60) following an oral sugar test (OST) in ponies with equine metabolic syndrome. Therefore, circulating AA might be a useful marker for insulin dysregulation (ID) and laminitis risk. Objective: To explore the relationship between circulating AA concentrations at baseline (T0) and T60 in ponies that developed laminitis within six months and non-laminitic ponie...
Orientin Reverses Premature Senescence in Equine Adipose Stromal Cells Affected by Equine Metabolic Syndrome Through Oxidative Stress Modulation. Equine metabolic syndrome (EMS) is a prevalent endocrine disorder associated with insulin dysregulation, oxidative stress, and impaired regenerative capacity of adipose-derived stem cells (ASCs). The aim of this study was to evaluate the effects of orientin-a plant-derived flavonoid with known antioxidant properties-on equine ASCs (EqASCs) derived from both clinically healthy and diagnosed EMS-affected mares. EqASCs were treated with orientin to evaluate its biological effects. The analysis included key cellular functions such as proliferative capacity, viability, apoptosis, oxidative stress, ...
Ferulic acid mediates Mongolian horse skeletal muscle fiber remodeling through PDK1. Ferulic acid (FA), a natural antioxidant and major active component in Angelica sinensis, has beneficial effects on skeletal muscle health; however, its role in modulating muscle fiber type composition Mongolian horse remains unclear. In this study, we found that FA promotes the proliferation of Mongolian horse skeletal muscle satellite cell (MuSCs), upregulates the expression of fast-twitch muscle marker genes (e.g., MYH2), and downregulates the expression of slow-twitch markers (e.g., MYH7). RNA-seq revealed that FA activates the HIF-1 signaling pathway, significantly increasing PDK1 express...
Metabolomics analysis and mRNA/miRNA profiling reveal potential cardiac regulatory mechanisms in Yili racehorses under different training regimens. Yili horses, a versatile breed from Xinjiang, China, are renowned for their racing abilities. However, studies on the links between cardiac morphology, function, and metabolic profiles with performance are limited. This study combined echocardiographic, transcriptomic, and metabolomic analyses to explore these relationships in high-level, average, and untrained Yili horses. Echocardiographic assessments revealed increased left ventricular mass in trained horses, with significant differences in intraventricular septal thickness and left ventricular end-diastolic diameter. RNA sequencing identif...
Reference Intervals for Biochemical Analytes in Clinically Healthy Adult Lusitano Horses. To date, serum biochemical analytes reference intervals (RIs) in Lusitano horses have not been studied. This study aimed to establish the RIs for biochemical analytes following the American Society of Veterinary Clinical Pathology guidelines and to compare them with the general equine population's RIs. Blood samples were collected from 76 clinically healthy adult Lusitano horses, and RIs of 22 biochemical variables were determined using Reference Value Advisor software. Lusitano horse-specific RIs are proposed for the following variables: total protein (3.9-7.0 g/dL), albumin (2.5-3.8 g/dL), g...
Evaluating the extent to which ataxia and responsiveness to stimuli reflect the efficacy of xylazine sedation using pharmacokinetics. Clinical assessments of equine sedation typically rely on subjective observations, the accuracy of which is paramount to the safety of equine veterinary procedures. Methods: To assess the degree in which subjective clinical sedative evaluations reflect pharmacokinetic measurements of equine drug metabolism, xylazine hydrochloride, an alpha-2 adrenoreceptor agonist, was administered to 36 horses of varying breed and age at a dosage of 0.5 mg/kg body weight. Subjective clinical parameters were scored at 5-, 15-, 30-, 45- and 60-minutes post xylazine administration and included responsiveness to ...
Obesity-Associated Metabolomic and Functional Reprogramming in Neutrophils from Horses with Asthma. Equine asthma is a chronic respiratory disease characterised by neutrophilic inflammation, airway hyperresponsiveness, and impaired pulmonary function. Obesity, increasingly prevalent among domestic horses, has been identified as a potential risk factor for exacerbating inflammatory conditions. This study aimed to explore whether obesity modifies neutrophil metabolism and inflammatory responses in horses affected by asthma. Six asthmatic horses in clinical remission were categorised into two groups: obese and non-obese, based on body condition score. Serum levels of interleukin-1β (IL-1β) an...
Exploring the distinctive characteristics of gut microbiota across different horse breeds and ages using metataxonomics. Gut microbiota exerts a pivotal function in host nutrient metabolism and maturation of the mucosal immunity. Analyzing the reciprocal interaction between horses and gut microbiota constitutes a crucial aspect of scientific feeding practices. This study aims to investigate the differences in gut microbiota among Hequ horses, Mongolian horses, and Thoroughbred horses, as well as between Thoroughbred horses at two age stages. Unassigned: Paired-end sequencing with a read length of 2×250 bp targeting the V3-V4 region of the 16S rRNA gene in fecal samples was carried out. Subsequently, differences...
Integrated Transcriptomic and Proteomic Analysis Reveals Differential Gene and Protein Expression and Signaling Pathways During a 20 Km Endurance Exercise and Recovery in Mongolian Horses. Mongolian horses are renowned for their remarkable endurance and ability to adapt to harsh environments. To delve deeper into the molecular mechanisms that underlie these traits, researchers conducted a comprehensive analysis of transcriptomic and proteomic changes in Mongolian horses at three distinct time points: before, immediately after, and 24 h following a 20 km run. The transcriptomic analysis uncovered significant variations in gene expression patterns across these time points. Specifically, 291 differentially expressed genes (DEGs) were identified when comparing pre-exercise to post-e...
Comprehensive Integrated Analyses of Proteins and Metabolites in Equine Seminal Plasma (Horses and Donkeys). The reproductive ability of equine species is a critical component of equine breeding programs, with sperm quality serving as a primary determinant of reproductive success. In this study, we perform an integrative analysis of proteomics and metabolomics in seminal plasma to identify proteins and metabolites associated with sperm quality and reproductive ability in equine species. Methods: We utilized the CEROS instrument to assess the morphology and motility of sperm samples from three horses and three donkeys. Additionally, we statistically analyzed the mating frequency and pregnancy rates in...
Quantitative proteomics unveils potential plasma biomarkers and provides insights into the pathophysiological mechanisms underlying equine metabolic syndrome. Equine Metabolic Syndrome (EMS) is a multifactorial endocrine disorder characterized by obesity, insulin dysregulation (ID), and an increase in the risk of laminitis, a painful condition that can lead to euthanasia in severe cases. Diagnosing EMS is challenging and often relies on clinical history including obesity, difficulty in losing weight, and recurring episodes of laminitis. The gold standard for laboratory support of an EMS diagnosis is the identification of ID, with basal insulin being the simplest and most accessible method, especially in a field setting. However, various factors such...
The effects of a long-duration intravenous infusion of detomidine, with and without vatinoxan, on equine energy metabolism and urine composition. To assess the effects of a 4 hour detomidine constant rate infusion (CRI) with and without a vatinoxan CRI on energy metabolism and urine composition. Methods: Randomized, blinded, crossover study. Methods: Eight Finnhorses, 587 (550-620) kg [median (range)] and 13 (4-16) years old. Methods: Horses were administered an intravenous (IV) detomidine loading dose (0.01 mg kg) followed by 240 minutes CRI (0.015 mg kg hour) (DET) and the same detomidine protocol combined with an IV vatinoxan loading dose (0.15 mg kg) and CRI (0.05 mg kg hour) (DET+VAT). Blood samples for glucose, insulin, non-esteri...
Metabolic Studies of Nandrolone Decanoate in Castrated Horses After Intramuscular Administration. This paper describes the studies of the in vitro biotransformation of nandrolone decanoate and its metabolic fate in equine plasma and urine after intramuscular administration to castrated thoroughbred horses. The in vitro metabolic study was performed using homogenised horse liver, and the more prominent in vitro biotransformation pathways were found to include hydrolysis, reduction, oxidation and sulfation, mainly resulting in seven Phase I metabolites and one Phase II metabolite. The administration study of nandrolone decanoate was carried out using three retired thoroughbred geldings, e...