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.
Evaluation of Fecal Egg Count Tests for Effective Control of Equine Intestinal Strongyles. The American Association of Equine Practitioners strongly advocates evidence-based intestinal strongyle control in horses. It recommends targeted treatment of all heavy egg shedders (>500 eggs per gram (EPG) of feces), while the low shedders (0-200 EPG) are left untreated. As 50-75% of adult horses in a herd are low shedders, preventing them from unnecessary anthelmintic exposure is critical for tackling resistance. There are various fecal egg count (FEC) techniques with many modifications and variations in use, but none is identified as a gold standard. The hypothesis of the study was that...
Large animal ventilator-integrated volumetric capnography generates clinically acceptable values of physiologic dead space in anesthetized healthy adult horses. To evaluate the agreement between the Tafonius large animal ventilator-integrated volumetric capnography (vCap) software and the Respironics NICO noninvasive cardiac output monitor reference system. Methods: Data were collected from 56 healthy adult horses undergoing general anesthesia. Methods: Animals were placed under general anesthesia and connected to the Tafonius large animal ventilator circle system. A flow partitioning device with CO2 and flow sensors was utilized to couple the endotracheal tube to the NICO monitor. Tafonius CO2 and flow sensors are incorporated into the Y-piece of the...
Dose effect and duration of action of liposomal bupivacaine administered as a perineural analgesic in a reversible and adjustable frog-pressure model of equine lameness. To determine the dose effect of peri-neural liposomal bupivacaine (LB) in an induced forelimb lameness model. Methods: 12 clinically normal adult horses. Methods: A randomized cross-over design was performed with 1 limb receiving saline and the other LB: low dose (6), high dose (6). Lameness was induced in 1 forelimb using a frog-pressure model. In the lame limb, peri-neural injection of the palmar nerves at the proximal sesamoid bones was performed using saline, low dose LB (0.25 mg/kg) (LDLB), or high dose LB (0.5mg/kg) (HDLB) in random order with a 1-week washout period between treatments. ...
Prevalence and diversity of ascarid and strongylid nematodes in Australian Thoroughbred horses using next-generation sequencing and bioinformatic tools. The study presents the results of a cross-sectional survey to describe the epidemiology of ascarid and strongylid nematodes in horses, the impact of diverse climatic conditions on parasite diversity and the levels of faecal egg shedding in different age groups of managed Thoroughbred horses. Individual faecal samples (n = 1377) collected from 62 Thoroughbred farms across four climatic zones in Australia were analysed using the modified McMaster technique for faecal egg counts (FECs) and strongylid nematodes were identified utilising PCR-directed next-generation sequencing (NGS) of the second...
Morphine concentrations in distal thoracic limb synovial fluid following intravenous regional limb perfusion in horses. Twelve adult horses were randomly assigned to 2 groups in a prospective experimental trial. A pneumatic tourniquet (425 mmHg) was placed, under sedation, proximal to the carpus on one randomly chosen thoracic limb. A cephalic vein catheter was placed distal to the tourniquet to establish an intravenous regional limb perfusion technique (IVRLP) with morphine (0.1 mg/kg) diluted with saline 0.9% to 0.1 mL/kg, and the tourniquet left in place for 30 minutes. Horses were euthanized at 1 h (Group I) or 6 h (Group II) following the IVRLP and synovial fluid from the radiocarpal, intercarpal, metacarp...
Fecal microbiota transplant for treatment of diarrhea in adult hospitalized horses-111 cases (2013-2018). Fecal microbiota transplant (FMT) is increasingly administered as part of the treatment of colitis in horses, yet there is little data as to its effectiveness. Retrospective evaluation of the effects of FMT on discharge status, fecal consistency, length of hospitalization, and improvement in clinical signs in horses hospitalized for diarrhea. Retrospective case-control study. Medical records of adult horses (>1 year old) that received at least one transfaunation treatment (2013-2018) in two referral hospitals were identified through a medical records database search. Medical records of contemp...
Percutaneous ultrasonic debridement of equine tendinopathy and desmopathy: A report of 10 cases. Tendinopathy and desmopathy are significant causes of morbidity in horses. To evaluate the use of percutaneous ultrasonic debridement (PUD) as a treatment for chronic tendinopathy and desmopathy in the horse. Eight adult horses with 10 affected limbs presented for lameness, ranging from 60-700 days postinjury. Diagnostic ultrasound identified the following: suspensory branch desmitis ( = 1), suspensory body desmitis ( = 2), Achilles tendinopathy ( = 1), desmitis of the accessory ligament of the deep digital flexor (DDF) tendon ( = 1), DDF tendinopathy ( = 2), and superficial digital flexor ten...
Comparison of Computed Tomography Assisted 3D Cephalometric Measurements in Straight Egyptian Arabian and Thoroughbred Horses. Dental malocclusions are commonly encountered in horses. The objective of this study was to report the normal cephalometric values from skull computed tomography (CT) scans of adult Straight Egyptian Arabian (SEAR) and thoroughbred (TB) horses and to compare differences in the measurements between the two breeds. Standing skull CTs were performed on 29 clinically normal adult horses (15 SEAR; 14 TB) and cephalometric measurements were taken. All 9 cephalometric measurements, as well as the interincisal angle, were found to be significantly greater in TB than SEAR ( < 0.05). TB were foun...
A comparison of rectal versus fetlock temperatures in dorsally recumbent horses during general anesthesia. To investigate the effect of isoflurane anesthesia on thermoregulation and peripheral heat loss in dorsally recumbent horses. Methods: Prospective, clinical study. Methods: Seven adult horses (2.6 ± 1.5 years old, 455 ± 70.2 kg). Methods: Horses underwent elective surgical procedures in dorsal recumbency under general anesthesia (GA) maintained with isoflurane in oxygen. Rectal (TR), intranasal (TN) and fetlock surface temperatures (TF) were measured every 10 minutes for the first 80 minutes following induction of GA. Room temperature (TRO) was monitored during the study. Statistical analysi...
Effect of Sugar Beet Pulp on the Composition and Predicted Function of Equine Fecal Microbiota. The purpose of this study is to determine the effect of the partial replacement of dietary hay with sugar beet pulp (SBP) on the composition and predicted function of the fecal microbiota of healthy adult horses. Fecal samples were collected daily for 12 days from six adult horses after removal from pasture, including a five-day acclimation period, and a seven-day period following the introduction of SBP into their diet, and compared to six untreated horses over a comparable period. Fecal DNA was subjected to 16S rRNA amplicon sequencing and a longitudinal analysis was performed comparing the ...
Evaluation of the hoof centre-of-pressure path in horses affected by chronic osteoarthritic pain. The Centre of Pressure (COP) is the single point summarising all forces transferred to the hoof during the stance phase of a stride. COP path (COPp) is the trajectory that COP follows from footstrike to lift-off. Aim of the present study was to characterize the COP and COPp in horses affected by osteoarthritis and chronic lameness. Seventeen adult horses with a diagnosis of osteoarthritis and single limb chronic lameness were recruited. The COP was recorded using a wireless pressure measuring system (TekScan®) with sensors taped to the hooves (either fore- or hind limb, depending on lameness ...
Detection of fungi in the airways of horses according to the sample site: a methodological study. Fungal detection in equine airways may be performed on either tracheal wash (TW) or bronchoalveolar lavage fluid (BALF) by either cytology or culture. However, method comparisons are sparse. Our objective was to determine the prevalence of fungi in airways of horses according to the sample site and laboratory methodology. Sixty-two adult horses, investigated in the field or referred for respiratory disease, were included. Tracheal wash, and BALF collected separately from both lungs, were collected using a videoendoscope. Fungi were detected in cytologic samples examined by light microscopy, an...
Retrospective evaluation of acute kidney injury in horses treated with nonnitrogenous bisphosphonates (2013-2020): 8 cases. To describe a population of horses with acute kidney injury (AKI) following administration of bisphosphonates including clinical signs, clinicopathologic data, treatment, and outcome. Methods: Retrospective study from August 2013 to July 2020. Methods: Veterinary university teaching hospital. Methods: Eight adult horses with AKI following administration of nonnitrogenous bisphosphonates. Methods: None. Results: Five horses received intramuscular clodronate (5/8; 62.5%) and 3 horses received intravenous tiludronate (3/8; 37.5%). Six horses (6/8; 75%) received concurrent nonsteroidal anti-inflam...
Association of equine gammaherpesvirus-5 with facial lymphohistiocytic interface dermatitis in seven adult horses from the United States. Equine herpesvirus-5 (EHV-5) is commonly found in healthy asymptomatic horses worldwide. Although a cause-and-effect relationship has not been thoroughly determined, this virus has been associated with several disease conditions including equine multinodular pulmonary fibrosis (EMPF) and 1 case of interface dermatitis. The authors searched the New York State Animal Health Diagnostic Center database for cases of equine interface dermatitis between 2007 and 2022. Ten cases were identified and scrutinized for viral inclusion bodies which were present in 5 of 10 cases. Two similar cases with inter...
Regulatory T lymphocytes and selected cytokines in horses with mild to severe equine asthma and different inflammatory cytology profiles. This study determined Tregs and inflammatory cytokines in BALF and peripheral blood (PB) of adult horses with mild and severe asthma and different BALF cytological inflammation profiles. Horses of diverse breeds with asthma (age range: 2-20 years, n = 24) were divided into groups according to the number of points obtained in a standardized clinical scoring system (mild-moderate equine asthma - MEA, severe equine asthma - SEA) and according to the inflammation type based on cytological finding. Plasma levels of IFN-γ, IL-4, IL-10, IL-17 and MMP-9 in the BALF were determined by ELISA. Tregs ...
Phenylbutazone concentrations in synovial fluid following administration via intravenous regional limb perfusion in the forelimbs of six adult horses. Pain management is critical to equine welfare with non-steroidal anti-inflammatory drugs (NSAID) commonly used in horses. However, systemic NSAID use is limited by harmful gastrointestinal and renal side effects. Intravenous regional limb perfusion (IVRLP) is a technique used in horses that produces high, local antibiotic concentrations while limiting systemic circulation. NSAID-IVRLP would be a novel method of local pain management while limiting systemic NSAID side effects. To date, NSAID-IVRLP administration has not been reported in horses. This study aimed to identify the pharmacokinetics ...
Survival of formalin intoxication in a 13-year-old Thoroughbred gelding. Formalin intoxication via the gastrointestinal route has not been previously reported in the horse. Whereas ingestion of formalin in humans, although rare, is well documented. Majority of human cases are either accidental, suicidal or homicidal and often lead to fatality, with a reported lethal formaldehyde dose equating to 0.12 - 0.16 g/kg bwt. Objective: To describe a single case report of the clinical management of an adult horse referred to a veterinary teaching hospital following accidental administration of 10% formalin via nasogastric tube. Methods: A 13-year-old Thoroughbred gelding or...
Preliminary evaluation of reference intervals for a point-of-care viscoelastic coagulation monitor (VCM Vet) in healthy adult horses. To evaluate a point-of-care viscoelastic coagulation monitor (VCM Vet) for use in horses by assessing variability between devices and establish reference intervals (RIs) for healthy adult horses. Methods: Prospective observational study. Methods: Two university teaching hospitals. Methods: Healthy adult horses (n = 68). Methods: None. Results: Blood collected by direct jugular venipuncture was applied directly from the syringe into 2 VCM Vet cassettes to establish coefficients of variation (CVs) and RIs for reported parameters of clotting time (CT), clot formation time (CFT), alpha angle, am...
Diagnosis and management of thyroid disorders and thyroid hormone supplementation in adult horses and foals. Equine thyroid disorders pose a diagnostic challenge in clinical practice because of the effects of nonthyroidal factors on the hypothalamic-pituitary-thyroid axis, and the horse's ability to tolerate wide fluctuations in thyroid hormone concentrations and survive without a thyroid gland. While benign thyroid tumours are common in older horses, other disorders like primary hypothyroidism or hyperthyroidism in adult horses and congenital hypothyroidism in foals are rare. There is a common misunderstanding regarding hypothyroidism in adult horses, especially when associated with the clinical pro...
Utility of serum amyloid A in monitoring clinical response to antimicrobial treatment in horses with bacterial pneumonia. Serum amyloid A (SAA) is a major acute phase protein in horses which could be a useful tool for assessing clinical response to treatment of bacterial pneumonia in adult horses.
Effect of ambulation following 18F-fluorodeoxyglucose injection on standing positron emission tomography of the healthy equine digit. Measure 18F-FDG uptake in digital tissues of healthy horses subjected to different ambulatory conditions between the time of injection and positron emission tomography (PET) scan acquisition. Methods: 8 healthy adult horses. Methods: Horses were walked (AMB) or tied in stalls (NONAMB) immediately after injection with ∼1.5 MBq/kg 18F-FDG until scan acquisition using a randomized crossover design. Steps were quantified using accelerometers. Standardized uptake values (SUV; mean and maximum) in digital tissues including the dorsal lamellae (proximal, middle, and distal), quarter lamellae (media...
Assessment of calcium, phosphorus, magnesium, vitamin D and PTH levels in sera of lame horses. Minerals play vital roles in physiologic processes. Calcium, phosphorus and magnesium are common minerals. Secretion, absorption and homeostasis of these minerals are affected by associations between the active vitamin D and parathyroid hormone (PTH). The aim of this study was to assess concentrations of vitamin D, PTH and minerals, such as calcium, phosphorus and magnesium in horse sera, as well as associations of these values with lameness in horses. In the references, the reasons for lameness can be deficiency and imbalance of minerals, and clinical observations also confirm this and there ...
Diagnostic Performance of Multi-Detector Computed Tomography Arthrography and 3-Tesla Magnetic Resonance Imaging to Diagnose Experimentally Created Articular Cartilage Lesions in Equine Cadaver Stifles. The purpose of the study was to determine the diagnostic performance of computed tomographic arthrography (CTA) and 3-Tesla magnetic resonance imaging (MRI) for detecting artificial cartilage lesions in equine femorotibial and femoropatellar joints. Methods: A total of 79 cartilage defects were created arthroscopically in 15 cadaver stifles from adult horses in eight different locations. In addition, 68 sites served as negative controls. MRI and CTA (80-160 mL iodinated contrast media at 87.5 mg/mL per joint) studies were obtained and evaluated by a radiologist unaware of the lesion distributi...
Effect of Procaine Penicillin G and Flunixin Meglumine on Serum Amyloid A Response in Healthy Adult Horses. This study was designed to determine the effect of PPG and/or flunixin meglumine on SAA response when used at clinical dosing regimens in healthy adult horses. Six healthy adult horses were enrolled in a crossover study design including one control and three treatment groups: no treatment (control); PPG alone (intramuscularly q12h for 72h); flunixin meglumine alone (intravenously q24h for 72h); and PPG (intramuscularly q12h for 72h) and flunixin meglumine (intravenously q24h for 72h). Whole blood was collected at 0, 24, 48, 72, 96 and 120 hours post-initial drug administration to measure SAA u...
Post-anesthetic CPS and EQUUS-FAP scores in surgical and non-surgical equine patients: an observational study. Equine pain scoring may be affected by the residual effect of anesthetic drugs. Unassigned: To compare pain scores in the hours immediately following anesthetic recovery to baseline pre-anesthetic scores in equine patients undergoing surgical and non-surgical procedures. Unassigned: Clinical observational study. Unassigned: Fifty adult horses undergoing anesthesia for surgical or non-surgical procedures were enrolled. Horses underwent pain scoring using the Composite Pain Score (CPS) and Equine Utrecht University Scale for Facial Assessment of Pain (EQUUS-FAP) prior to anesthesia (T0) and foll...
Relationship Between Selenium, Copper, Zinc and Their Biomarkers in Blood and Skeletal Muscle Tissue in Adult Horses From Southern Chile. Microminerals are necessary for all bodily functions. In animal species, selenium (Se), copper (Cu) and zinc (Zn) all form part of antioxidant enzymes. Micromineral deficiencies, particularly Se, are well recognized in large animal species in Chile. Glutathion peroxidase (GPx) is a widely used biomarker for Se nutritional status and to diagnose Se deficiency in horses. Superoxide dismutase (SOD) is a Cu and Zn-dependant antioxidant enzyme, although it is not commonly used as a proxy for the nutritional status of these minerals. Ceruloplasmin (CP) is used as a biomarker of Cu nutritional status...
Contrast administration via ultrasound-guided injection of the cranial tibial artery results in contrast enhancement of the soft tissues of the metatarsus in horses undergoing CT. Delivery of mesenchymal stem cells (MSC) via intravascular techniques to treat diffuse and/or inaccessible soft tissue injuries has grown in popularity. The purpose of the current prospective, analytical pilot study was to utilize CT to validate this novel technique and provide additional evidence to support its use for injectate delivery to specific soft tissue structures. Of particular interest was the proximal suspensory ligament, which presents a challenging injection target. Six adult horses without lameness underwent CT of the distal hindlimbs. Scans were obtained prior to ultrasound-gui...
Ex vivo evaluation of a novel suture loop method for equine intestinal biopsies. To compare a novel suture loop method for intestinal biopsies (SLB) with a two-layer, hand-sutured biopsy (HSB) technique in equine small and large intestines. Methods: Experimental, randomized, ex vivo study. Methods: Eight healthy adult horses. Methods: The duodenum, aboral jejunum, and ventral and dorsal large colon were harvested after euthanasia and divided into three sections each. The sections were randomized to SLB, HSB, or control (C, no biopsy) groups. Tissue samples were excised after placement of a suture loop formed by a 4S Roeder knot and oversewn with a Cushing pattern using bar...
Pharmacokinetics, clinical efficacy and safety of acetaminophen (paracetamol) in adult horses with naturally occurring chronic lameness. Acetaminophen is used clinically in horses with musculoskeletal pain; however, no studies have been performed in horses with chronic lameness. Objective: To determine the pharmacokinetics, safety and efficacy of chronic dosing of acetaminophen in horses with naturally occurring chronic lameness. Methods: Longitudinal. Methods: Twelve adult horses with chronic lameness were treated with acetaminophen (30 mg/kg PO) every 12 h for 21 days. Plasma concentrations of acetaminophen were analysed on days 7 and 21 via LC-MS/MS and noncompartmental pharmacokinetic analysis. Lameness was evaluated ...
Effects of a 10% dimethyl sulfoxide solution on radiocarpal joint amikacin pharmacokinetics during intravenous regional limb perfusion in standing sedated horses. To determine the effect of a 10% dimethyl sulfoxide (DMSO) solution on the peak concentration (C ) of amikacin in the radiocarpal joint (RCJ) during intravenous regional limb perfusion (IVRLP) compared with 0.9% NaCl. Methods: Randomized crossover study. Methods: Seven healthy adult horses. Methods: The horses underwent IVRLP with 2 g of amikacin sulfate diluted to 60 mL using a 10% DMSO or 0.9% NaCl solution. Synovial fluid was collected from the RCJ at 5, 10, 15, 20, 25, and 30 minutes after IVRLP. The wide rubber tourniquet placed on the antebrachium was removed after the 30 min sample. A...