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.
Suagee-Bedore J, Shost N, Miller C, Grado L, Bechelli J.Older horses and those prone to obesity may be at a higher risk for inflammation than younger and leaner counterparts. Previous research indicated a postprandial elevation in plasma concentrations of interleukin-1β (IL-1β), a pro-inflammatory cytokine, after consuming 1.2 g of non-structural carbohydrates/kilogram of body weight. However, these studies utilized horses of mixed age and body condition. The current study evaluated post-prandial IL-1β concentrations in horses specifically comparing lean to over-conditioned and middle aged to older. Our results suggest that at least two weeks of...
Autry JM, Svensson B, Carlson SF, Chen Z, Cornea RL, Thomas DD, Valberg SJ.We have analyzed the enzymatic activity of the sarcoplasmic reticulum (SR) Ca2+-transporting ATPase (SERCA) from the horse gluteal muscle. Horses are bred for peak athletic performance yet exhibit a high incidence of exertional rhabdomyolysis, with elevated levels of cytosolic Ca2+ proposed as a correlative linkage. We recently reported an improved protocol for isolating SR vesicles from horse muscle; these horse SR vesicles contain an abundant level of SERCA and only trace-levels of sarcolipin (SLN), the inhibitory peptide subunit of SERCA in mammalian fast-twitch skeletal muscle. Here, we re...
Vaughn SA, Norton NA, Hart KA.Mechanisms resulting in breed predispositions to insulin dysregulation (ID) are poorly characterized. Cortisol antagonizes insulin, and free, biologically active cortisol can be increased in ID. Breed-related differences in serum free cortisol fraction (FCF) could contribute to ID, but FCF has not been quantified in equidae predisposed to ID, such as ponies. To compare FCF and other hypothalamic-pituitary-adrenal (HPA) axis hormones between horses and ponies during health and ID. We hypothesized: (1) FCF is higher in ponies than horses in health, and is higher still in ponies with ID and obes...
Karikoski NP, Box JR, Mykkänen AK, Kotiranta VV, Raekallio MR.The oral sugar test (OST) is commonly used to diagnose insulin dysregulation (ID) and equine metabolic syndrome; however, possible seasonal changes in OST results have not been evaluated. Objective: To determine the possible variation in insulin response to OST throughout the year and risk factors associated with maximum insulin concentration (InsMax) and ID. Methods: Prospective, longitudinal cohort study. Methods: The OST was performed on 29 Finnhorses every other month six times. Serum total adiponectin concentration and phenotypic variables related to obesity were also measured. Changes in...
Paßlack N, van Bömmel-Wegmann S, Vahjen W, Zentek J.Zinc supplements are often used in equine nutrition to support skin and hoof quality or the immune function. However, no data on the effects of dietary zinc on the intestinal microbiota of horses and ponies are available so far. In the present study, varying dietary zinc concentrations (maintenance (4 mg/kg BW/day), 120 mg/kg dry matter (DM)/day and 240 mg/kg DM/day) were achieved by the supplementation of either zinc chloride hydroxide or zinc methionine (six treatment periods of 4 weeks each). Eight healthy adult ponies and two healthy adult horses were included, and faecal samples were coll...
Grenager NS.Endocrinopathic laminitis (EL) primarily occurs because of insulin dysregulation (ID) mediated through downstream effects of insulin on IGF-1R in lamellar tissues. There is likely contributing vascular and metabolic dysfunction within the lamellae, but EL is relatively non-inflammatory. EL is associated with lamellar stretching, proliferation, and failure, ultimately causing failure of the suspensory apparatus of the distal phalanx. Proper education regarding mitigating risk factors makes this a largely preventable cause of laminitis. Annual hoof evaluation plus screening geriatric horses for ...
Burns TA.Nutrition plays an important role in equine health, including that of the foot. Deficiencies and excesses of dietary components can affect the growth and function of the foot and have been associated with important podiatric diseases. The recognition, prevention, and treatment of specific notable nutritional diseases of the foot are discussed, as well as information regarding specific ingredients included in supplements meant to improve equine hoof quality. Ensuring provision of a balanced diet, maintaining horses in appropriate body condition, and seeking guidance from an equine nutritionist ...
Raspa F, Dinardo FR, Vervuert I, Bergero D, Bottero MT, Pattono D, Dalmasso A, Vinassa M, Valvassori E, Bruno E, De Palo P, Valle E.Horses reared for meat production are fed high amounts of cereal grains in comparison with horses raised for other purposes. Such feeding practice may lead to risk of poor welfare consequences. The aim of this study was to investigate the effects of two feeding practices on selected metabolic parameters and production aspects. Nineteen Bardigiano horses, 14.3 ± 0.7 months of age, were randomly assigned to two groups-one fed with high amounts of cereal grains (HCG; n = 9; 43% hay plus 57% cereal grain-based pelleted feed) vs. one fed with high amounts of fibre (HFG; n = 10; 70% hay plus...
Lyn Macon E, Harris P, Partridge E, Day Barker V, Adams A.The oral sugar test (OST) is frequently used to identify insulin dysregulated (ID) equines. The effect of fasting and varying sugar dose for the OST has been investigated in the pony but little work has been done in the horse. This study aimed to investigate (1) an OST response with access to forage continued until the time of the OST or prevented for 3 hours prior to the OST and (2) responses of ID and non-insulin dysregulated (NID) horses to two different OST doses. Twenty-one mixed-breed horses (14.8 ± 3.2 years; 574.3 ± 83.3 kg) were used in two randomized crossover studies. Seven ID and...
Sandagdorj B, Baigalmaa T, Burenjargal S, Horiuchi M, Enkhdalai M, Bayanbat D, Janchiv D, Jamyandorj O, Ulzii-Orshikh P, Nyam-Osor P.Information regarding the lactational performance of mares in relation to metabolic parameters can help practitioners to manipulate animal rearing management for sustainable mare milk production. The aim of this study was to characterize the lactational performance of Mongolian native mares grazing on natural pastureland by revealing the seasonal effects on metabolic parameters. In this study, 8 multiparous mares were used. Milk yield and composition and serum metabolic parameters, such as alanine aminotransferase, aspartate aminotransferase (AST), glucose (GLU), triacylglycerol, total cholest...
A deep knowledge on metabolic response of athlete horse to exercise is of paramount importance for the development of optimal training programs to attain equilibrium between good performance and animal welfare. This study investigated the dynamic change of metabolic, clotting times and peripheral indices of central fatigue in horses competing in an official 44 km endurance race. From 6 horses blood samples were collected at rest (T), within 5 minutes from the end of race (T), after 30, 60 minutes after the end of race (T and T) to investigate the values of blood lactate, glucose, platelet...
Zhu Y, Wang X, Liu B, Yi Z, Zhao Y, Deng L, Holyoak R, Li J.Silage is fed to horses in China and other areas in the world, however, knowledge about the impact of feeding silage on horse health is still limited. In the current study, 12 horses were assigned into two groups and fed ryegrass silage and ryegrass hay, respectively, for 8 weeks. High-throughput sequencing was applied to analyze fecal microbiota, while liquid chromatography-tandem mass spectrometry (LC-MS/MS) based metabolomics technique was used for blood metabolite profile to investigate the influence of feeding ryegrass silage (group S) compared to feeding ryegrass hay (group H) on equine ...
Lindinger MI.The TCO2 (total carbon dioxide) test is performed on the blood of racehorses as a means of combatting the practice of administering alkalizing agents for the purpose of enhancing performance. The purposes of this review are to present an overview of the factors contributing to TCO2 and to review the literature regarding TCO2 in adult Standardbred and Thoroughbred horses to demonstrate the range of variability of TCO2 in horses. Most of the research published on the topic of TCO2 or bicarbonate measurement in racehorses was accessed and reviewed. PubMed and Google Scholar were the primary sear...
D' Fonseca NMM, Beukers M, Wijnberg ID, Navas de Solis C, de Ruijter-Villani M, van Doorn DA, Stout TAE, Roelfsema E.Changes in cardiovascular parameters, including blood pressure (BP) and cardiac anatomical dimensions, are an inconsistent feature of the equine metabolic syndrome. The order in which these changes arise is unknown. Objective: Determine the order in which EMS-associated changes in cardiovascular parameters arise. Methods: Twenty Shetland pony mares. Methods: High-energy (HE) diet mares were fed 200% of net energy requirements for 1 (n = 3) or 2 (n = 7) consecutive diet-years, with 17 weeks of hay-only between years. Noninvasive BP measurements and echocardiograms were performed during bo...
Jiménez BLM, Elghandour MMMY, Adegbeye MJ, Tirado González DN, Tirado Estrada G, Salem AZM, Pacheco EBF, Pliego AB.In the race against deadly diseases, multiple drugs have been developed as a treatment strategy in livestock. Each treatment is based on a specific mechanism to find a suitable drug. Antibiotics have become a fundamental part of the equine industry to treat bacterial diseases. These antibiotics have specific doses and side effects, and understanding each parameter allows veterinarians to avoid or limit the adverse effects of such drugs. Use of antibiotics causes microbial imbalance, decreased microbial diversity and richness in both cecal and fecal samples. Antibiotics reduced metabolites prod...
Ragno VM, Klein CD, Sereda NS, Uehlinger FD, Zello GA, Robinson KA, Montgomery JB.In human metabolic syndrome and type II diabetes, methylglyoxal (MG), D-lactate, and several cytokines have been recognized as biomarkers of important metabolic and inflammatory processes. Equine metabolic syndrome (EMS) shares many similarities with these human counterparts. The objectives of this cross-sectional study were to compare body condition score (BCS), cresty neck score (CNS), resting insulin, MG, D-lactate, L-lactate, tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and monocyte chemoattractant protein-1 (MCP-1) between horses with and without insulin dysregulation, as clas...
Bookbinder L, Schott HC.To describe refeeding syndrome in an equid without a history of recognized risk factors. Methods: Refeeding syndrome with marked hypophosphatemia developed in an aged miniature donkey gelding during treatment of suspected enterocolitis. Hypophosphatemia (manifested clinically as ileus and neuromuscular weakness) developed despite a short (3 day) history of hyporexia, increased body condition (7/9), and adherence to nutritional recommendations for critically ill equids. Nutritional support included nasogastric enteral feeding with a commercial equine nutrition product claiming to provide 100% o...
Mendoza FJ, Mejia-Moreira S, Buchanan BR, Toribio RE, Perez-Ecija A.Insulin dysregulation (ID) and donkey metabolic syndrome (DMS) are common in this species. Contrary to horses, diagnostic guidelines compiling insulin cut-offs values and dynamic testing interpretations have not been reported for this species. Objective: To evaluate resting serum insulin concentrations, the combined glucose-insulin test (CGIT) and the glucose intravenous tolerance test (IVGTT) for the diagnosis of DMS with ID suspicion. Methods: Diagnostic test comparison. Methods: Six of 80 mix-breed adult donkeys fulfilled the inclusion criteria for DMS based on history or clinical evidence ...
Bradbery AN, Coverdale JA, Hammer CJ, Dunlap KA, Leatherwood JL, Satterfield MC.Skeletal muscle plays an integral role in the ability of a horse to perform at high levels. Shifts in skeletal muscle development in response to maternal plane of nutrition may have substantial and lasting impacts on athletic performance and whole-body metabolism. Therefore, sixteen Quarter Horse mares were used in a completely randomized design and maintained at a body condition score (BCS) 6 until start of third trimester. On d 235 of gestation, mares were randomly assigned to receive one of two dietary treatments with a diet formulated to meet requirements during late gestation (CON; n = ...
Johnson ACB, Biddle AS.Thriftiness in horses has been associated with more efficient nutrient harvesting in digestion, absorption and/or utilization, but the relative contribution of the gut microbiome to host metabolic tendency is not well understood. Recognizing the unreliability of owner reported assignment of keeper status, this research describes a novel tool for calculating whether a horse is an easy (EK) or hard (HK) keeper and then characterizes microbiome differences in these groups. The Equine Keeper Status Scale (EKSS) was developed and validated based on data gathered from 240 horses. Estimates of dietar...
Asin J, Murphy BG, Samol MA, Polanco J, Moore JD, Uzal FA.Rickets is a metabolic bone disease associated with failure of endochondral ossification and impaired osteoid mineralization in growing animals. As a consequence, affected individuals can develop gross and microscopic bone malformations. The most common causes of rickets in domestic species include vitamin D and phosphorus deficiency. Rickets has been described in multiple species; however, comprehensive postmortem characterizations with confirmatory histopathology in equids have not been published. A 6-mo-old, Thoroughbred-cross foal was diagnosed with rickets based on gross autopsy findings ...
Leng J, McNally S, Walton G, Swann J, Proudman C, Argo C, Emery S, La Ragione R, Eustace R.Gut microbial communities are increasingly being linked to diseases in animals and humans. Obesity and its associated diseases are a concern for horse owners and veterinarians, and there is a growing interest in the link among diet, the intestinal microbiota and metabolic disease. Objective: Assess the influence of long-term hay or haylage feeding on the microbiota and metabolomes of 20 Welsh mountain ponies. Methods: Longitudinal study. Methods: Urine, faeces and blood were collected from 20 ponies on a monthly basis over a 13-month period. Urine and faeces were analysed using proton magnetic...
Wilson S, Spriet M, Mur PE, Anishchenko S, Beylin D, Katzman S, Galuppo L.Lesions of the deep digital flexor tendon (DDFT) are a cause for foot lameness in horses. Positron emission tomography (PET) could provide valuable information regarding the metabolic activity of these lesions. The aims of this exploratory, prospective, methods comparison study were to assess the ability of fluorine-fluorodeoxyglucose ( F-FDG) PET to detect DDFT lesions and to compare the PET findings with CT and MRI findings. Eight horses with lameness due to pain localized to the front feet were included. Both front limbs of all horses were imaged with F-FDG PET, noncontrast CT, and arteri...
Ertelt A, Merle R, Stumpff F, Bollinger L, Liertz S, Weber C, Gehlen H.The purpose of this study was to assess a change in different blood parameters before and after a 160 km endurance race and to evaluate differences in cardiac biomarkers between horses that completed the race and horses that did not. The study population consisted of 52 healthy endurance horses. Horses participating in the study were assigned to three groups: horses that successfully completed the race ("finishers"), horses that failed to qualify at the veterinary check for primarily metabolic reasons ("metabolic") and horses that failed to qualify at the veterinary check for primarily gait re...
Walshe N, Cabrera-Rubio R, Collins R, Puggioni A, Gath V, Crispie F, Cotter PD, Brennan L, Mulcahy G, Duggan V.Obesity is endemic in human populations in the western society, and with mounting evidence that the intestinal ecological environment plays a major role in its pathogenesis, identification of therapies based on intestinal microbiota modulation are gaining attention. Obesity in companion animals is also a common clinical problem. We set out using a multidimensional approach, to determine the effectiveness and safety of a weight loss program for horses incorporating diet restriction and exercise. In addition, we aimed to investigate the effect of this program on the overall intestinal health of ...
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...
Nagy A, Murray JK, Dyson S.Endurance is the fastest growing Féderation Équestre International (FEI) discipline and the large number of eliminations on veterinary grounds needs to be investigated. Objective: To document elimination rates and explore potential risk factors for elimination due to lameness or metabolic reasons in 9 countries representing 5 continents. Methods: Data for rides of ≥ 100 km ('elite endurance rides') in Australia, France, Italy, South Africa, Spain, United Arab Emirates (UAE), UK, Uruguay and USA were collected from the FEI website. Data were collected for all started horses on the country, ...
Smith S, Harris PA, Menzies-Gow NJ.The in-feed oral glucose test (OGT) and oral sugar test (OST) are advocated as field tests of insulin sensitivity in horses and ponies but have not been directly compared. Objective: To compare the insulin response to OGT and OST in 8 ponies and 5 horses of unknown insulin sensitivity. Methods: Experimental, randomised crossover study. Methods: Animals were fasted for 8 h overnight before and throughout testing. They were fed 1 g/kg bwt glucose powder with chaff (OGT) or 0.15 ml/kg bwt corn syrup (Karo™ Light Syrup; OST) was administered per os in a randomised crossover study with 48...
McGowan CM, Frost R, Pfeiffer DU, Neiger R.Serum insulin concentration and its use as a prognostic indicator in horses with equine Cushing's syndrome (ECS) have been poorly documented. Objective: To examine daily insulin variations in horses with ECS and the effect of treatment using trilostane, a competitive inhibitor of 3beta-hydroxysteroid dehydrogenase. Further, we aimed to examine the relationship between baseline serum insulin concentration and survival in horses with ECS. Methods: Basal serum insulin concentrations were measured in 20 confirmed ECS cases by taking blood at regular 4 h intervals for 24 h (1200, 1600, 2000, 2400, ...
Kornicka K, Śmieszek A, Węgrzyn AS, Röcken M, Marycz K.Endocrine disorders, including equine metabolic syndrome (EMS), are a serious issue in veterinary medicine and horse breeding. Furthermore, EMS was shown to affect the cytophysiological properties of adipose-derived stem cells, reducing their therapeutic potential. However, it was shown that those cells can be rejuvenated while using a combination of two chemicals: 5-azacytydine (AZA) and resveratrol (RES). In the present study, we decided to evaluate the immunomodulatory properties of AZA/RES-treated adipose-derived stem cells (ASC) isolated from EMS horses (ASC). Thus, we co-cultured ASC wit...
Wylie CE, Collins SN, Verheyen KL, Newton JR.Laminitis is a highly debilitating disease of the foot known to have a complex and multifactorial aetiology of metabolic, inflammatory, traumatic or vascular origin. The disease has major welfare implications due to unrelenting pain associated with degenerative changes, which often necessitate euthanasia on welfare grounds. Despite this, there have been few high-quality studies investigating risk factors for equine laminitis, and only a limited number of risk factors have been previously investigated. The aim of this study was to conduct a case-control study of risk factors for active episodes...
Martin RB, Lau ST, Mathews PV, Gibson VA, Stover SM.We studied birefringence as an indicator of collagen fiber orientation in the diaphysis of the equine third metacarpal bone. We had previously shown that tissue from the lateral cortex of this bone is stronger monotonically, but less fatigue resistant, than tissue from the medial and dorsal regions. To learn whether collagen fiber orientation might play a role in this regional specialization, we tested three hypotheses using the same specimens: (1) collagen fiber orientation is regionally dependent; (2) remodeling changes collagen fiber orientation; (3) longitudinal collagen fibers correlate p...
Geor RJ, Harris P.Insulin resistance (IR) and hyperinsulinemia increase risk for development of laminitis in horses and ponies. Obesity also has been associated with heightened risk for laminitis, likely by means of development of IR. Dietary factors, particularly the nonstructural carbohydrate (NSC) load, modulate risk for laminitis in these animals by means of exacerbation of IR or gastrointestinal disturbances that trigger the condition. Specific dietary management strategies to lessen risk for laminitis include caloric restriction to promote weight loss and improve insulin sensitivity in obese animals and s...
Waller AP, Burns TA, Mudge MC, Belknap JK, Lacombe VA.Insulin resistance (IR) has been widely recognized in humans, and more recently in horses, but its underlying mechanisms are still not well understood. The translocation of glucose transporter 4 (GLUT4) to the cell surface is the limiting step for glucose uptake in insulin-sensitive tissues. Although the downstream signaling pathways regulating GLUT translocation are not well defined, AS160 recently has emerged as a potential key component. In addition, the role of GLUT12, one of the most recently identified insulin-sensitive GLUTs, during IR is unknown. Objective: We hypothesized that cell-su...
Gentry LR, Thompson DL, Gentry GT, Davis KA, Godke RA, Cartmill JA.An experiment was conducted to determine the effects of high vs low body condition scores (BCS) produced by restricted feeding on reproductive characteristics, hormonal secretion, and leptin concentrations in mares during the autumnal transition and winter anovulatory period. Mares with BCS of 6.5 to 8.0 were maintained on pasture and/or grass hay, and starting in September, were full fed or restricted to produce BCS of 7.5 to 8.5 (high) or 3.0 to 3.5 (low) by December. All but one mare with high BCS continued to ovulate or have follicular activity during the winter, whereas mares with low BCS...
Reynolds A, Keen JA, Fordham T, Morgan RA.Obesity is a common feature of equine metabolic syndrome (EMS). In other species, obese adipose tissue shows pathological features such as adipocyte hypertrophy, fibrosis, inflammation and impaired insulin signalling all of which contribute to whole body insulin dysregulation. Such adipose tissue dysfunction has not been investigated in horses. Objective: To determine if obese horses with EMS have adipose tissue dysfunction characterised by adipocyte hypertrophy, fibrosis, inflammation and altered insulin signalling. Methods: Cross-sectional post-mortem study. Methods: Samples of peri-renal (v...
Sessions-Bresnahan DR, Schauer KL, Heuberger AL, Carnevale EM.Obesity is associated with disrupted reproductive cycles in mares, but the impact of obesity on follicles and oocytes has received minimal attention. We investigated the impact of obesity on 1) expression of selected genes in follicle cells for carbohydrate metabolism, inflammatory cytokines, lipid homeostasis, endoplasmic reticulum stress, and mitochondrial function; 2) follicular fluid content of metabolic hormones and metabolites; and 3) lipid fingerprint of oocytes. Mares (9-13 yr) were classified as control (n = 8, normal weight, body condition score [BCS] 5.1, 10.4% body fat) or obese (n...
Journal of proteomicsApril 2, 2020
Volume 221 103765 doi: 10.1016/j.jprot.2020.103765
Martín-Cano FE, Gaitskell-Phillips G, Ortiz-Rodríguez JM, Silva-Rodríguez A, Román Á, Rojo-Domínguez P, Alonso-Rodríguez E, Tapia JA, Gil MC....Proteomic technologies allow the detection of thousands of proteins at the same time, being a powerful technique to reveal molecular regulatory mechanisms in spermatozoa and also sperm damage linked to low fertility or specific biotechnologies. Modifications induced by the cryopreservation in the stallion sperm proteome were studied using UHPLC/MS/MS. Ejaculates from fertile stallions were collected and split in two subsamples, one was investigated as fresh (control) samples, and the other aliquot frozen and thawed using standard procedures and investigated as frozen thawed subsamples. UHPLC/M...
Place NJ, McGowan CM, Lamb SV, Schanbacher BJ, McGowan T, Walsh DM.Determination of adrenocorticotropic hormone (ACTH) concentration is a commonly used test in the evaluation of endocrine causes of equine laminitis, but the concentration in healthy horses can be high at certain times of year, which alters the specificity of the ACTH test. Objective: To determine if circulating concentrations of ACTH, cortisol, glucose, insulin, and thyroxine vary month to month in healthy horses and in horses with equine metabolic syndrome (EMS). Methods: Nine healthy adult horses were studied on their farm/stable over the course of 1 year. After the diagnosis of EMS, 10 lami...
Powell DM, Reedy SE, Sessions DR, Fitzgerald BP.Twelve untrained aged mares were used to determine whether 7 days of light exercise improved peripheral tissue insulin sensitivity. Mares were divided into obese-exercised (n = 3), obese-sedentary (n = 3), lean-exercised (n = 3) and lean-sedentary (n = 3) groups. The exercised groups were worked at a trot to a heart rate (HR) of not more than 140 beats/min for 30 min in a round pen. Each group was subjected to 3 euglycaemic hyperinsulinaemic clamps: prior to exercise (P), 24 h following the seventh exercise training session (E) and 9 days postexercise training (PE). Prior to exercise training,...
Jacob SI, Geor RJ, Weber PSD, Harris PA, McCue ME.Glucose and insulin dynamics may be different in adult and aged horses. Objective: To determine the effects of age and dietary carbohydrates on glucose and insulin dynamics in healthy horses. Methods: Balanced Latin square with four isocaloric diets: CONTROL (hay plus restricted-starch-and-sugar fortified pellets), STARCH (control plus kibbled corn), FIBER (control plus unmolassed sugar beet pulp/soybean hull pellets) and SUGAR (control plus dextrose powder). Methods: A total of 16 healthy Thoroughbreds and Standardbreds divided into two age groups: ADULT (8.8 ± 2.9 years; n = 8) and AGE...
de Laat MA, Hampson BA, Sillence MN, Pollitt CC.Obesity in horses is increasing in prevalence and can be associated with insulin insensitivity and laminitis. Current treatment strategies for obesity include dietary restriction and exercise. However, whether exercise alone is effective for decreasing body fat is uncertain. Objective: Our hypothesis was that twice daily use of a dynamic feeding system for 3 months would induce sustained, low-intensity exercise thereby decreasing adiposity and improving insulin sensitivity (SI). Methods: Eight, university-owned, mixed-breed, adult ponies with body condition scores (BCS) ≥5/9 were used. Metho...
Ertelt A, Barton AK, Schmitz RR, Gehlen H.This review summarizes similarities and differences between the metabolic syndromes in humans and equines, concerning the anatomy, symptoms, and pathophysiological mechanisms. In particular, it discusses the structure and distribution of adipose tissue and its specific metabolic pathways. Furthermore, this article provides insights and focuses on issues concerning laminitis in horses and cardiovascular diseases in humans, as well as their overlap.
Stowe HD, Herdt TH.Assessment of the selenium status of livestock is an important aspect of production medicine, but variations in reported values between laboratories and between methods may be > 30%. Reliable interpretations require considerable experience with an assay and an extensive database from field and research case samples of a variety of species. The Michigan State University Animal Health Diagnostic Laboratory (MSU-ADHL) has offered Se analyses by acid-digestion and fluorometric detection since 1982. This laboratory expects serum Se values (nanograms per milliliter) of livestock to increase graduall...
Harris RC, Marlin DJ, Snow DH.To define the metabolic response to maximal exercise in the thoroughbred horse under field conditions, muscle biopsies and venous blood samples were taken from five horses after a single 800-m gallop and from four horses after a single 2,000-m gallop. Muscle and blood samples were also collected during 60 min of recovery. After exercise muscle ATP contents were decreased by 30 +/- 7 (SD) and 47 +/- 3% after the 800- and 2,000-m gallops, respectively. As indicators of purine catabolism, ammonia and uric acid increased in plasma, the accumulation being greater after the 2,000-m gallop. Blood amm...
Barrey E, Mucher E, Jeansoule N, Larcher T, Guigand L, Herszberg B, Chaffaux S, Guérin G, Mata X, Benech P, Canale M, Alibert O, Maltere P, Gidrol X.Several cases of myopathies have been observed in the horse Norman Cob breed. Muscle histology examinations revealed that some families suffer from a polysaccharide storage myopathy (PSSM). It is assumed that a gene expression signature related to PSSM should be observed at the transcriptional level because the glycogen storage disease could also be linked to other dysfunctions in gene regulation. Thus, the functional genomic approach could be conducted in order to provide new knowledge about the metabolic disorders related to PSSM. We propose exploring the PSSM muscle fiber metabolic disorder...
Meier A, Reiche D, de Laat M, Pollitt C, Walsh D, Sillence M.There are no registered veterinary drugs for treating insulin dysregulation and preventing insulin-associated laminitis in horses. Velagliflozin is a sodium-glucose co-transport 2 inhibitor that reduces renal glucose reabsorption, promotes glucosuria, and consequently, decreases blood glucose and insulin concentrations. This study aimed to determine if velagliflozin reduced hyperinsulinemia and prevented laminitis in insulin-dysregulated ponies fed a challenge diet high in non-structural carbohydrates (NSC). An oral glucose test (1 g dextrose/kg BW) was used to screen 75 ponies for insulin dys...
Frank N, Elliott SB, Chameroy KA, Tóth F, Chumbler NS, McClamroch R.Pituitary pars intermedia dysfunction (PPID) is a risk factor for pasture-associated laminitis, which follows a seasonal pattern. Objective: Hormonal responses to season differ between PPID and unaffected horses. Methods: Seventeen horses aged 8-30 years (14 horses ≥ 20 years of age). Methods: Longitudinal observational study. Blood was collected monthly from August 2007 until July 2008 after pasture grazing and again after overnight stall confinement. Blood hormone and metabolite concentrations were measured and pasture grass samples were analyzed to determine carbohydrate content. Analysis...
Waller AP, Kohler K, Burns TA, Mudge MC, Belknap JK, Lacombe VA.Although the importance of adipose tissue (AT) glucose transport in regulating whole-body insulin sensitivity is becoming increasingly evident and insulin resistance (IR) has been widely recognized, the underlying mechanisms of IR are still not well understood. The purpose of the present study was to determine the early pathological changes in glucose transport by characterizing the alterations in glucose transporters (GLUT) in multiple visceral and subcutaneous adipose depots in a large animal model of naturally occurring compensated IR. AT biopsies were collected from horses, which were clas...
Borer-Weir KE, Bailey SR, Menzies-Gow NJ, Harris PA, Elliott J.To evaluate a human radioimmunoassay (RIA) and equine and high-range porcine (hrp) species-specific ELISAs for the measurement of high serum insulin concentrations in ponies. Methods: Serum samples from 12 healthy nonobese ponies (7 clinically normal and 5 laminitis prone; 13 to 26 years of age; 11 mares and 1 gelding) before and after glucose, insulin, and dexamethasone administration. Methods: Intra-and interassay repeatability, freeze-thaw stability, dilutional parallelism, and assay agreement were assessed. Results: Assay detection limits were as follows: RIA, < 389 μU/mL; equine ELISA...
Schott HC.PPID in older equids has become a major health concern of horse owners. In response, equine practitioners have made greater efforts at understanding, diagnosing, and treating this disorder. Although PPID is recognized to be a different form of pituitary-dependent hyperadrenocorticism than is seen in canine or human patients, relatively little is known about the pathophysiology and natural progression of the disease. At present, the diagnosis is best supported by manifestation of characteristic clinical signs and endocrinologic test results, preferably a supportive DST result. Treatment must fo...
Bamford NJ, Baskerville CL, Harris PA, Bailey SR.The enteroinsular axis is a complex system that includes the release of incretin hormones from the gut to promote the absorption and utilization of glucose after a meal. The insulinogenic effect of incretin hormones such as glucagon-like peptide-1 (GLP-1) remains poorly characterized in the horse. The aim of this study was to compare postprandial glucose, insulin, and GLP-1 responses of different equine breeds adapted to twice-daily meals containing micronized maize. Four Standardbred horses, 4 mixed-breed ponies, and 4 Andalusian cross horses in moderate BCS (5.5 ± 0.2 out of 9) were fed mea...
Hodavance MS, Ralston SL, Pelczer I.Metabonomic analysis is a powerful tool for identifying and characterizing metabolic disorders, for example type 2 diabetes and the metabolic syndrome. Nuclear magnetic resonance (NMR) spectroscopy is an essential tool for such analysis, with special benefits. The review assesses the current status and potential of NMR-based metabonomics of type 2 diabetes. The horse is proposed as a possible model for studying this condition and disease. Some examples are shown of horse blood analyses by NMR.
Rendle DI, Rutledge F, Hughes KJ, Heller J, Durham AE.Metformin is a potential therapeutic agent for the treatment of insulin resistance (IR). In laboratory animals, orally administered metformin reduces intestinal glucose absorption and may therefore affect insulinaemic responses to oral carbohydrate ingestion. Objective: To determine whether pretreatment with metformin reduces plasma glucose concentration and insulin responses following consumption of dextrose in horses. Methods: Therapeutic cross-over study. Methods: Seven healthy Standardbred and Thoroughbred geldings were subjected to an oral dextrose challenge test on 4 occasions: with and ...
Giles SL, Nicol CJ, Rands SA, Harris PA.Nuchal crest adiposity in horses and ponies has been associated with an enhanced risk of metabolic health problems. However, there is no current information on the prevalence of, and risk factors specific to, nuchal crest adiposity in horses and ponies. In addition, the cresty neck score has not previously been utilised across different seasons within a UK leisure population, it is not know whether nuchal crest adiposity shows the same seasonal trends as general obesity. Results: A Cresty Neck Score (CNS, 0-5) was given to 96 horses with access to pasture (>6 h per day) at the end of winter a...
Durham AE, Rendle DI, Newton JE.Laminitis in equids is a very common debilitating disease, and insulin resistance (IR) and hyperinsulinaemia are increasingly recognised as important predisposing factors. Pharmacological modification of IR and hyperinsulinaemia might reduce the risk of laminitis. Objective: Metformin, a drug commonly prescribed for treatment of human IR, may also decrease IR in equids. Methods: Eighteen horses and ponies with IR and recurrent laminitis were treated with 15 mg/kg bwt metformin per os q. 12 h. Each animal served as its own control by comparing pre- and post treatment proxies for IR, insulin sen...
