Topic:Adult Horses
Adult horses encompass a category of equines that have reached maturity, typically considered to be around five years of age and older. This stage of life is characterized by full physical development and the potential for peak performance in various activities such as riding, racing, and work. Adult horses require specific nutritional, health, and management practices to maintain optimal condition and performance. The study of adult horses covers a range of topics, including physiology, behavior, and the impact of environmental factors on their well-being. This page compiles peer-reviewed research studies and scholarly articles that explore the physiology, health management, and performance aspects of adult horses.
The Effect of Ambient Temperature, Relative Humidity, and Temperature-Humidity Index on Stress Hormone and Inflammatory Response in Exercising Adult Standardbred Horses. In the present study, the changes in the markers of stress and inflammatory responses of 12 Standardbred horses were investigated before and after exercise during late spring and summer. The environmental temperature, relative humidity, and temperature-humidity index (THI) were assessed during this study. From horses, blood sampling, measurement of heart and respiratory rate (HR and RR), and measurement of rectal temperature (RT) were performed before exercise (Pre) and within 5 min following the end of the exercise (Post). THI values showed mild stress in June and high stress in July. Direct ...
Volume kinetics of lactated Ringer’s solution in adult horses. Fluid therapy in horses is primarily empirical. Evidence-based quantification of the disposition of intravenous (IV) crystalloids used in clinical practice could enhance the effectiveness of fluid therapy. Objective: To determine the pharmacokinetics (i.e., volume kinetics: VK) and associated haemodynamic effects of IV lactated Ringer's solution (LRS) in adult euvolemic horses. Methods: Unmasked multiple subjects, single baseline design. Methods: Thirteen healthy, euvolemic adult female horses were administered an IV bolus of LRS and monitored over 4 h. Haemoglobin, albumin and haematocrit c...
apEvaluation of circulating microRNAs in plasma from horses with non-strangulating intestinal infarction and idiopathic peritonitis. Non-strangulating intestinal infarctions (NSII) associated with Strongylus vulgaris infection and idiopathic peritonitis (IP) share similar clinical presentation but require different treatment approaches. Horses with NSII need surgical intervention, while idiopathic peritonitis cases can be successfully treated with antimicrobials. A correct diagnosis is thus crucial, but because the two diseases overlap in clinicopathological features, differentiation is difficult in clinical practice. MicroRNAs (miRNAs) are non-coding RNAs that exhibit measurable changes in abundance in tissues and circulat...
Morphological variations of the interatrial septum and potential implications in equine cardiology. The interatrial septum morphology, shaped by the septum primum and secundum fusion, results in the formation of the fossa ovalis (FO) and its limbus. Incomplete fusion can lead to a patent foramen ovale (PFO), while complete fusion may produce septal ridges and pouches (SPs), with SPs in humans linked to ischemic stroke and atrial arrhythmias. In horses, atrial tachycardia and fibrillation often originate near the FO. This study examines adult equine interatrial septum morphology to enhance understanding the region and guide electrophysiological interventions for equine cardiac arrhythmias. Po...
An Ex Vivo Comparison of Stainless Steel Cables to a Non-metallic Polymer Cerclage Cable in an Equine Metacarpophalangeal Joint Arthrodesis Model. The aim of this study was to compare the monotonic tensile strength and fatigue strength of a stainless steel cable (SSC) compared to a human non-metallic polymer cable (NMPC) in an metacarpophalangeal joint arthrodesis model lacking a dorsal plate application.An experimental biomechanical equine cadaver limb study. Ten metacarpophalangeal joints were collected from five adult Thoroughbred horses, euthanatized for reasons unrelated to orthopaedic disease. Each pair of metacarpophalangeal joints was randomly instrumented with either a 1.7-mm SSC or a NMPC. Each construct was tested in cyclic ...
INJECTION OF THE INSERTION OF THE COLLARAL LIGAMENT OF THE DISTAL INTERPHALANGEAL JOINT IN STANDING HORSES USING THE PALMAR RADIOGRAPHIC-GUIDED APPROACH. Injury to the collateral ligament (CL) of the distal interphalangeal joint (DIPJ) is recognized as a source of lameness in horses. Intralesional injection has been advocated to increase return to performance. This study was a proof-of-concept study in standing horses to evaluate success of a palmar radiographic-guided approach for injecting insertions of the DIPJ CLs previously described in cadaver limbs. Horses were sedated, nerve blocked, and placed on wooden blocks with the limb to be injected staggered approximately 20cm cranially to the other limb. The DIPJ CL insertion was injected, usin...
Rein tension and heart rate variability in horses: an experiment on experience. Studies on stress and emotions are fundamental to assessing welfare in wild and domestic animals. In this study, we experimentally investigated how different levels of rein tension affect autonomic nervous system activation and heart rate variability (HRV) in horses. We hypothesized that increased rein tension, through a learning process, would elevate sympathetic nervous system activity and HRV, and that adult horses would be less affected by stimulus administration (EXP) than young horses due to their experience. The magnitude of rein tension significantly altered the sympatho-vagal balance ...
Long-Term Firocoxib Use in Horses. Many horses receive firocoxib over multiple years, and studies evaluating hematologic and biochemical values in these animals are lacking. Objective: To describe the hematologic and biochemical values of horses receiving long-term firocoxib. Methods: A total of 79 horses receiving long-term firocoxib and 153 horses not receiving long-term firocoxib and not presenting for a specific medical problem. Methods: Retrospective study comparing horses receiving firocoxib (F group) and no firocoxib (NF group). Signalment, hematologic, and biochemical values were compared between the two groups. Simple ...
Acute changes in serum iron concentrations in anesthetized healthy horses. To determine if serum iron concentrations decrease acutely during and after general anesthesia in healthy horses. Methods: Prospective experimental study. Methods: A convenience sample of 24 healthy adult horses (eight females, 16 geldings), weighing 545 ± 33 kg (mean ± standard deviation). Methods: Horses were anesthetized for 120 minutes with isoflurane, after premedication with intravenous (IV) xylazine (0.8 mg kg-1) and induction with IV midazolam (0.1 mg kg-1) and ketamine (2.2 mg kg-1). Blood samples for serum iron analysis were obtained just before premedication (baseline), after 60 m...
Novel Intracardiac Ultrasound Images Developed on a Cardiac Ultrasound Simulator and Validated in Live Horses. Ultrasonographic guidance of catheter-based interventions in horses is based primarily on transthoracic echocardiography (TTE). Intracardiac echocardiography (ICE) has the potential to provide detailed imaging of specific cardiac regions. Insight and training in echocardiographic guidance can be acquired using an echocardiography simulator. Objective: Use an echocardiography simulator for horses to determine specific ICE views for catheter-based interventions and validate these in live horses. Methods: Six adult healthy experimental horses. Methods: Observational study. An echocardiographic ph...
Pilot Study: Simultaneous Daily Recording of Total Locomotor Activity and Heart Rate in Horses for Application in Precision Livestock Farming. Among physiological parameters, total locomotor activity (TLA) and heart rate (HR) are used as physiological indicators in animal welfare evaluations. The present study aimed to simultaneously record for 24 h the TLA and HR of ten clinically healthy horses housed in conventional individual boxes subjected to a natural photoperiod and temperature. An actigraphy-based data logger was placed on the headstall, and an equine HR monitor was placed around the chest to monitor TLA and HR, respectively. Activity was monitored with 5 min sampling intervals and HR with 5 s intervals. To make the data poi...
Assessing the inflammatory response in horses undergoing gastric ulceration using salivary ADA and S100A12 as biomarkers. The inflammatory status in horses with gastric ulcers was monitored by two inflammatory biomarkers, S100A12 and adenosine deaminase (ADA), using saliva samples from healthy and horses with gastric ulcers. Two trials were developed: an experimental trial, in which gastric ulceration was induced in 8 horses by feed deprivation, and a clinical trial, in which 20 horses without any symptomatology and 37 with symptoms compatible with gastric ulcers were used. S100A12 and ADA levels were measured in the saliva samples of all horses using previously validated assays. In both trials, horses with gastr...
Lipidomics and biochemical profiling of adult Yili horses in a 26 km endurance race: exploring metabolic adaptations. The equine lipid metabolism is activated during and after endurance exercise to provide energy in response to the metabolic and physiological changes in the body caused by prolonged exercise; however, the specific regulatory mechanisms remain controversial and identifying differential lipid metabolites associated with equine endurance is essential to elucidate these regulatory mechanisms. In this study, blood samples for lipid metabolomic analysis and biochemical indices were collected before and after a 26 km race from 12 Yili horses with different endurance performance. The biochemical res...
What is the “train track” in the retained equine testis? A 3-year-old Quarter horse stallion with unilateral left cryptorchidism was referred for the absence of the left testis in the scrotal bursa and an enlarged right testis. The ultrasonographic examination revealed the presence of the left testis at the abdominal level. Two small hyperechogenic lines were observed running parallel and resembling a cylindrical cavitary foreign body, within a non-homogeneous area with blurred margins. The testis was removed by laparoscopy and macroscopically, the testis's cut section revealed the presence of two live adult nematodes emerging from 2 mm blood-filled...
Dynamic Adaptation of Heart Rate and Autonomic Regulation During Training and Recovery Periods in Response to a 12-Week Structured Exercise Programme in Untrained Adult and Geriatric Horses. Changes in resting heart rate (HR) and HR variability (HRV) are utilised to assess training effects in horses. However, limited research has examined how these variables reflect training effects during exercise sessions and recovery periods, particularly in horses of different ages. This study investigated how HR and HRV changed during exercise sessions and recovery periods in untrained adult horses (UAHs; = 9) and geriatric horses (UGHs; = 9). HR and HRV were measured before and during a 54 min exercise bout over a 12-week training programme. Mixed-effects model with Greenhouse-Geisser corr...
Physiological and behavioral parameters of pain and stress in mares during and after transvaginal ultrasound-guided follicular aspiration. The use of transvaginal ultrasound-guided follicle aspiration (TVA) for oocyte collection has become a widely used procedure in horses for embryo production (IVEP). The TVA procedure is characterized by various manipulations, which are physical restraint, perineal preparation, transrectal palpation, insertion of an intravaginal device, and needle punctures. These repeated transvaginal and transovarian punctures have raised concerns about their potential effects on mare welfare. Our study aimed to investigate the effects of TVA manipulations, and especially puncturing, on pain and stress in ma...
Papillary Renal Cell Carcinoma With Widespread Metastases in an Arabian Mare. This report describes a case of massive renal cell carcinoma (RCC) causing mild chronic colic in a 20-day-postpartum Arabian mare. The mare presented with deteriorating abdominal pain following normal parturition. Clinical examination revealed tachycardia, tachypnoea, weak intestinal motility and pale mucosal membranes. Rectal examination identified a very large mass in the caudal part of the abdominal cavity, and abdominal ultrasound examination revealed a huge space-occupying mass with renal architecture. During midline exploratory laparotomy, a massive tumour was observed in the anatomical ...
Plasma Lipidomics and Proteomics Analyses Pre- and Post-5000 m Race in Yili Horses. The impact of exercise on human metabolism has been extensively studied, yet limited research exists on the effects of high-intensity racing on equine metabolism. The aim of this study was to screen the effect of a 5000 m race on lipids and proteins in the plasma of Yili horses for the breeding of racehorses. Blood samples were collected from the top three finishers, and lipidomics and proteomics analyses were performed. Lipidomic analysis identified 10 differential lipids. Compared to pre-race levels, phosphatidylethanolamine (18:0/16:0) (PE (18:0/16:0)) and phosphatidylcholine (18:0/18:2) (P...
Cardiopulmonary effects of oral trazodone administration prior to isoflurane anesthesia in healthy horses. To determine the cardiopulmonary effects of oral trazodone before isoflurane anesthesia in systemically healthy horses. Unassigned: 12 horses donated for euthanasia (from August 2022 through June 2023) due to conditions unrelated to the cardiovascular system were included in this prospective, randomized, controlled trial. Horses were assigned to receive oral trazodone (6 mg/kg; n = 7) or corn syrup (n = 5) 1 hour before xylazine (1 mg/kg, IV) sedation, ketamine (2.2 mg/kg, IV) and propofol (0.7 mg/kg, IV) induction, and anesthetic maintenance with inhaled isoflurane (target 1.6% expired) for 7...
Collecting equine whole blood in glass tubes does not decrease adrenocorticotropic hormone concentration compared to plastic tubes. Pituitary pars intermedia dysfunction is diagnosed using immunoreactive ACTH concentrations. Glass reportedly binds ACTH, but the clinical relevance of using glass blood tubes for measuring equine ACTH concentrations is controversial. This study investigates whether the collection of whole blood into glass EDTA tubes and storage for up to 6 hours changes ACTH concentrations compared to plastic EDTA tubes. Unassigned: This was a cohort study. Whole blood was collected into both glass and plastic EDTA tubes from 9 horses > 12 years of age, including 4 with pituitary pars intermedia dysfunction a...
Clinical use of antimicrobial regional limb perfusion in adult horses diagnosed with synovial sepsis or penetrating synovial wounds at a single equine referral hospital in the Midwest United States-163 cases (2010-2020). The clinical outcomes in horses diagnosed with established synovial sepsis (SS) or minimally contaminated synovial wounds (SW)/non-established sepsis, following intravenous regional limb perfusion (IVRLP) treatment, have not been reported since 2010. Additionally, previous reports on this subject were confined to just two clinical retrospective reports. This study aimed to provide an update on the short-term (hospital discharge) and long-term (≥1 year) survival rates in adult horses diagnosed with SS or SW treated with IVRLP at a single institution in the USA from 2010-2020. The study also...
Association Between Adrenocorticotropic Hormone Concentration and Clinical Signs of Pituitary Pars Intermedia Dysfunction in Swiss and Austrian Equids. There remains a scarcity of data concerning the relationship between the clinical signs associated with PPID and plasma ACTH concentrations. Objective: Report the frequency of clinical signs in the study cohort and identify individual clinical signs or combinations of clinical signs associated with high ACTH concentrations. Methods: Two hundred eighty equids were examined by private veterinarians. Methods: A cross-sectional study of animals with clinical suspicion of PPID was conducted between August and November. Private practitioners completed an online questionnaire reporting detailed infor...
Resistivity and Pulsatility Indexes Renal Values Do Not Differ When Obtained from Abdominal or Transrectal Approaches in Healthy Horses. Early detection of renal deficient function is imperative for the success of treatments and determining prognosis. In horses, a renal ultrasound can be performed through the abdominal wall (TA) or transrectally (TR), being an important tool for the evaluation of the kidneys. Besides renal morphology, resistivity (RI) and pulsatility indexes (PI) may be early tools to detect renal injury as they reflect arterial compliance. Twenty-nine healthy adult horses were sonographically evaluated by TA and TR approaches, measuring RI and PI on both kidneys. The mean values from the TA for RI and PI in th...
Effects of Age, Sex, and Exercise on Measurement of Serum CTnI Levels and Some Parameters Related to the Cardiovascular Capacity of Caspian Horses. Due to their high specificity and exclusive cardiac myocyte sensitivity, cardiac troponins T and I (cTnT, cTnI) are currently regarded as ideal biomarkers to identify cardiomyocyte damage, myocardial injury, myocardial infarction, and chronic heart failure. In fact, cTnI is considered the most reliable biomarker for diagnosing heart-related issues. This study aimed to investigate the effects of age, gender, and exercise training on serum cTnI levels and various parameters related to the cardiovascular capacity of Caspian horses. For this purpose, 50 adult Caspian horses over 3 years old, both ...
Corticosteroid Administration Enhances the Glycemic, Insulinemic, and Incretin Responses to a High-Protein Mixed Meal in Adult Horses. Corticosteroids are used routinely in horses and induce insulin dysregulation (ID). Nutrition is important for ID management and includes low nonstructural carbohydrate (NSC) diets and, often, high-protein ration balancers (RB). Insulin and incretin secretion increase after high-protein meals; corticosteroids may influence these effects. Objective: A high-protein mixed meal will induce hyperinsulinemia and increased concentrations of glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide 1 (GLP-1) in horses with ID; dexamethasone (DEX) will amplify this effect. Methods: F...
Comparison of a dorsolateral approach and a dorsomedial approach to access the medial malleolus of the distal tibia in horses. To determine the utility of a dorsolateral arthroscopic approach to the tarsocrural joint (TCJ) to examine and surgically access the medial malleolus (MM) and compare this to the standard dorsomedial approach to the MM. Methods: Experimental cadaver study. Methods: Six pelvic limbs from four adult horses. Methods: Arthroscopic examination of the dorsal aspect of the TCJ was performed followed by the dorsomedial and dorsolateral surgical approaches to the MM, in randomized order on cadaver limbs (n = 6). The dorsomedial approach involved placing the arthroscope and instrument in the dorsome...
Differences in serum iron concentrations between the summer and winter in Noma horses. We examined the differences in serum iron (Fe) concentrations and related variables between summer and winter in Noma horses. Blood samples were collected from 37 clinically normal horses seven consecutive times: September 2018, February 2019, October 2019, February 2020, September 2020, February 2021, and February 2022. Serum Fe concentrations ranged from 74 μg/dl to 316 μg/dl with a median of 176 μg/dl. The concentrations were lower in stallions compared with mares and geldings, tended to be low at 10-14 years of age, and then increased with age. Serum Fe concentrations were repeatedly lo...