Omneity® Pellets
All-In-One Vitamin & Mineral Pellet
Topic:Anatomy
Anatomy in horses encompasses the study of the structural organization of the equine body, including the bones, muscles, organs, and systems that function together to sustain life and enable movement. Understanding equine anatomy is important for veterinarians, equine scientists, and horse owners, as it provides insights into how horses move, how they respond to external stimuli, and how various conditions can affect their health and performance. Key anatomical features in horses include the musculoskeletal system, which provides support and locomotion; the cardiovascular system, which circulates blood and nutrients; and the respiratory system, which facilitates gas exchange. This page compiles peer-reviewed research studies and scholarly articles that explore the detailed anatomy of horses, focusing on the structure and function of different body systems, their interrelationships, and their relevance to equine health, performance, and veterinary care.
Assessment of Vein Diameter and Body Surface Temperature after High-Intensity Laser Therapy (HILT) on the Tarsal Joint in Healthy Horses. The aim of the study was to assess the influence of high-intensity laser therapy (HILT) on vein diameter and on body surface temperature changes in the tarsal joint area in a group of clinically healthy racehorses. The hypothesis of the study was that HILT increases vein diameter and body surface temperature in healthy tissue. The study involved 16 Thoroughbreds being subjected to ultrasonographic examination to assess changes of diameter of the cranial branch of the medial saphenous vein and thermographic examination to indicate temperature change of the dorsal surface of the tarsal joint, ju...
Extramuscular Recording of Spontaneous EMG Activity and Transcranial Electrical Elicited Motor Potentials in Horses: Characteristics of Different Subcutaneous and Surface Electrode Types and Practical Guidelines. Adhesive surface electrodes are worthwhile to explore in detail as alternative to subcutaneous needle electrodes to assess myogenic evoked potentials (MEP) in human and horses. Extramuscular characteristics of both electrode types and different brands are compared in simultaneous recordings by also considering electrode impedances and background noise under not mechanically secured (not taped) and taped conditions. Methods: In five ataxic and one non-ataxic horses, transcranial electrical MEPs, myographic activity, and noise were simultaneously recorded from subcutaneous needle (three brands) ...
Influence of a purpose-built frame on the accuracy of computer-assisted orthopedic surgery of equine extremities. To determine the influence of a purpose-built frame on the accuracy of screw placement during computer-assisted orthopedic surgery (CAOS) of the equine extremity. Methods: Experimental cadaveric study. Methods: Twenty-four paired equine cadaveric limbs obtained from seven horses. Methods: Three 4.5-mm cortex screws were inserted in lag technique in three different planes of orientation in the proximal phalanx (P1) by means of CAOS. In the study group (n = 12 limbs), the tracker was anchored on a purpose-built frame designed to stabilize the extremity. In the control group (n = 12 limbs), a con...
The contribution of the middle cerebral artery and callosal artery to the vascularisation of the Facies convexa of the brain in horses with reference to the equine-specific cartographic pattern of the neopallium. The extremely complex surface architecture of the equine brain does not allow a uniform transfer of anatomical data from other mammalian species, e.g., dog or cat. Rather, a special approach is required to elucidate the equine-specific patterns of cerebral vascular ramifications. Therefore, a novel cartographic system was applied. Prior attention was paid to the A. cerebri media (MCA) and to the A. corporis callosi (CA), as they spread over the widest part of the neopallium's Facies convexa (i.e. the lateral and dorsal surface), thus being of particular interest in terms of surgical treatment ...
Arthroscopic approach and intra-articular anatomy of the equine discomandibular joint compartment of the temporomandibular joint. To develop an arthroscopic approach to the discomandibular joint (DMJ), the ventral compartment of the temporomandibular joint (TMJ) of the horse. Methods: Experimental study. Methods: Nine cadaveric equine heads and two live horses. Methods: A 2.5-mm 30° arthroscope was used to explore the DMJ after joint distension. The first portal was created caudally, allowing placement of a rostral portal under visual guidance. Nasotracheal intubation of the live horses allowed mandibular manipulation, which is required for complete visualization of the joint. Results: A novel injection technique allowe...
Real-time three-dimensional (3D) echocardiographic characterisation of an atrial septal defect in a horse. Atrial septal defects have been well reported in humans and dogs and the principles of intervention have been well established. In contrast, there is very little information published about these congenital anomalies in horses. True ASDs are regarded as rare and little is known about the clinical significance of these defects in horses. An 11-year-old Thoroughbred gelding with a history of poor performance was diagnosed with an atrial septal defect, measuring approximately 2 cm in diameter, on 2D transthoracic echocardiography. Real-time three-dimensional (3D) echocardiography was used to map...
Development of a computer-based quantification method for immunohistochemically-stained tissues and its application to study mast cells in equine wound healing (proof of concept). There is a growing interest in the scientific community to use computer-based software programs for the quantification of cells during physiological and pathophysiological processes. Drawbacks of computer-based methods currently used to quantify immunohistochemical staining are the complexity of use, expense of software and overly-simplified descriptions of protocol thereby limiting reproducibility. The precise role of mast cells in equine cutaneous wound healing is unknown. Given the contribution of mast cells to the chronic inflammation observed in human keloid, a pathology similar to exuber...
Bimodal Whole-Mount Imaging of Tendon Using Confocal Microscopy and X-ray Micro-Computed Tomography. Three-dimensional imaging modalities for optically dense connective tissues such as tendons are limited and typically have a single imaging methodological endpoint. Here, we have developed a bimodal procedure utilising fluorescence-based confocal microscopy and x-ray micro-computed tomography for the imaging of adult tendons to visualise and analyse extracellular sub-structure and cellular composition in small and large animal species. Results: Using fluorescent immunolabelling and optical clearing, we visualised the expression of the novel cross-species marker of tendon basement membrane, lam...
Monolateral chronicon orchitis in a stallion. Orchitis and epididymo-orchitis are inflammatory lesions of the testicle. We herein describe a case of monolateral chronic orchitis which occurred in a Tiro Pesante Rapido (TPR) stallion, born in 2002, with a history of good fertility. The stallion was healthy and asymptomatic although the left testis was found to be smaller as compared with the right one and was hard in consistency. Histopathology examination revealed tubular atrophy and parenchymal sclerosis. Scattered foci of calcification and chronic inflammation, the latter dominated by macrophages and lymphocytes, were also observed. Alt...
Radiographic anatomy of the equine distal tibia. The radiographic anatomy of the equine distal tibia is complex and is not widely described in the current literature. Superimposition and radiographic similarities between the different osseous structures of the equine distal tibia can make it difficult for anatomic localization of pathology. The purpose of this prospective, descriptive, anatomic study was to detail the normal anatomy of the equine distal tibia using routine radiographic projections and CT of the equine tarsus. Radiographic identification of the different osseous protuberances of the distal tibia on three cadaveric limbs was a...
Retroperitoneoscopy in the horse: Anatomical study of the retroperitoneal perirenal space and description of a surgical approach. Surgical approaches to the kidneys and perirenal structures are uncommonly performed in horses and several complications have been described with the current procedures. Objective: To describe the anatomy of the retroperitoneal perirenal space and investigate a retroperitoneal minimally invasive approach to access the kidney and perirenal structures in horses. Methods: Descriptive, cadaveric study. Methods: Anatomical description of the retroperitoneal space was performed on three equine cadavers and the surgical approach was developed based on these dissections. Ten cadaveric horses underwent...
Morphometric measurements of the feet of working donkeys Equus asinus in Egypt. Working equids rely on sound, balanced hooves, but data describing the typical morphology of the legs and feet of working donkeys are currently lacking. To address this gap in knowledge, the front and hind feet of twenty healthy working donkeys were measured and compared. Hoof width, weight-bearing lengths, heel width, dorsal hoof wall length and lateral and medial heel length of the hoof wall were determined, as well as toe angle, heel angle, hoof pastern axis, coronary band angle and a measure of 'ground surface size'. Viewed from the ground surface of the foot, front feet were more rounded ...
Comparative studies on the histological characteristics of equine nasomaxillary aperture and paranasal sinus mucosa considering topographic and age-related differences. Horses may acquire a range of paranasal sinus diseases. Clinical studies show slight differences regarding anatomical regions and age. Histopathological examination of tissue samples could play an important role in the diagnostic process. Therefore, detailed knowledge of the histological appearance of the paranasal sinus mucosa (PSM) and the nasomaxillary aperture mucosa (NAM) is essential. The objective of this study was to determine topographic and age-related differences within the healthy equine PSM. In addition, we aimed to gain detailed knowledge of the histological appearance of the NAM...
A first comparison of bone histomorphometry in extant domestic horses (Equus caballus) and a Pleistocene Indian wild horse (Equus namadicus). The microstructural features of the tissue of long bones subjected to different biomechanical stresses could be a helpful tool for a better understanding of locomotor behavior in extant and extinct mammals, including equids. However, few researches have attempted to describe the bone tissue of extinct horses. In our study, we analyze and compare the histomorphometric features of the bone tissue in extant modern horses, Equus caballus, and Equus namadicus, a Pleistocene Indian extinct wild horse. The number, position, and size of the osteons and Haversian canals of the bone tissue, classifiable...
Effects of topical 1% cyclopentolate hydrochloride on quantitative pupillometry measurements, tear production and intraocular pressure in healthy horses. To evaluate the effect of topical cyclopentolate hydrochloride (CH) on quantitative pupillometric readings (PR), tear production (TP), and intraocular pressure (IOP) in healthy horses. Methods: Fourteen client-owned horses. Methods: In a two-phase design study, each animal received 1% CH ophthalmic solution in the left eye [treated] and 0.9% NaCl in the right eye [control] (0.2 mL each). In the first phase (n = 7), TP, IOP, and PR assessment was performed by Schirmer tear test I, rebound tonometry and static pupillometry, at 1, 8, 24, 48, 72, 96, 120, 148, 172, and 196-hours post-instillati...
Equine endometrial development during late fetal and postnatal periods. Equine uterine development, including endometrial histogenesis, begins prenatally and is completed postnatally. Little is known about this process in the horse. Uterine tissue was acquired from 38 foals, ranging in developmental age from gestational day (GD) 300 to postnatal day (PND) 180, for assessment of endometrial histogenesis. Patterns of endometrial cell proliferation were evaluated by multispectral imaging of uterine tissue sections stained immunofluorescently for Ki-67. Labeling index (LI, % labeled cells) for Ki-67 was calculated for each endometrial cell compartment (luminal epithel...
Morphometric Characteristics of the Skull in Horses and Donkeys-A Pilot Study. Horses and donkeys belong to the genus Equus, but important differences exist between the species, many of which affect their management and welfare. This study compared skull morphology between horses and donkeys. Horse ( = 14) and donkey ( = 16) heads were obtained post-mortem, sectioned sagittally close to the midline, and photographed for subsequent measurement of various skull structures. Skull, cranial, nasal, and profile indices were calculated for topographical comparisons between the species. The olfactory bulb area (OBA), OB pitch (the angle between the hard palate and the OB axis), ...
Reference Values and Repeatability of Transabdominal Ultrasonographic Gastrointestinal Tract Thickness and Motility in Healthy Donkeys (Equus asinus). The present study aimed to provide reference ranges for the wall thickness and motility pattern of the gastrointestinal tract from a sample of donkeys (Equus asinus) population using B-mode ultrasonography. In the present study, 30 clinically healthy donkeys (Equus asinus) (15 males and 15 females), aged 2-20 year old and weighed 100-280 kg were randomly selected for B-mode ultrasonographic scanning of the abdomen. The wall thickness of the stomach, duodenum, jejunum, left colon, right colon, and cecum was assessed. Moreover, the motility pattern of the duodenum, jejunum, left colon, right c...
Actinomyces as a Cause of Osteomyelitis of the Nasofrontal Suture in a Gelding. A 7-year-old American Quarter Horse gelding was referred to the JT Vaughan Large Animal Teaching Hospital at Auburn University, College of Veterinary Medicine, for an investigation of a recurrent swelling of the nasofrontal region. Computed tomography examination of the skull was most consistent with a sequestrum of the left nasofrontal suture with associated focal osteomyelitis and left conchofrontal sinusitis. Surgery to remove the sequestrum, debride the devitalized bone, and flush the left conchofrontal sinus was performed. A microbial culture was obtained at the time of surgery, which yie...
A pilot study of optical neuronavigation-guided brain biopsy in the horse using anatomic landmarks and fiducial arrays for patient registration. Optical neuronavigation-guided intracranial surgery has become increasingly common in veterinary medicine, but its use has not yet been described in horses. Objective: To determine the feasibility of optical neuronavigation-guided intracranial biopsy procedures in the horse, compare the use of the standard fiducial array and anatomic landmarks for patient registration, and evaluate surgeon experience. Methods: Six equine cadaver heads. Methods: Computed tomography images of each specimen were acquired, with the fiducial array rigidly secured to the frontal bone. Six targets were selected in ea...
Morphological Characteristics of the Placenta and Umbilical Cord of Arabian Mares Foaling in the United Arab Emirates. A total of 127 normal placentas from Arabian mares resident in the United Arab Emirates were examined. The mean linear dimensions of the placenta were, on average, 84% of those previously recorded for the placentas of the Thoroughbred. Significant differences in the size of the allantochorion between primigravid and multiparous mares were seen only in the linear dimensions of the body portion. The pregnant horn was more commonly on the right than left side of the uterus (P = .01; 74/127; 58%). Cord attachment was primarily at the base of the two placental horns (112/127; 88%), with the remain...
Immunohistochemical study of morphology and distribution of CD163+ve macrophages in the normal adult equine gastrointestinal tract. Intestinal macrophages are the largest group of mononuclear phagocytes in the body and play a role in intestinal innate immunity, neuroimmune interactions and maintaining intestinal homeostasis. Conversely, they also are implicated in numerous pathologies of the gastrointestinal tract, such as postoperative ileus and inflammatory bowel disease. As a result, macrophages could be potential therapeutic targets. To date, there are limited studies on the morphology and distribution of macrophages in the equine gastrointestinal tract (GIT). The aim of this study was to identify the location and abun...
Desensitisation of the distal forelimb following intrathecal anaesthesia of the carpal sheath in horses. The effect of intrathecal anaesthesia of the carpal sheath on distal forelimb sensitivity in horses remains unknown. Objective: To assess the effect of carpal sheath anaesthesia on skin sensitivity of the distal forelimb and to determine potential locations for desensitisation of palmar nerves. Methods: In vivo experimental and descriptive anatomical studies. Methods: Mepivacaine hydrochloride 2% (0.6 mg/kg) was injected unilaterally in the carpal sheath of 8 horses. Mechanical nociception of the distal forelimb was measured with a dynamometer and compared with the control limb at t0, t15, t3...
Is the T-ligament a ligament? A histological study in equine cadaver forelimbs. Foot pain is a frequent cause of lameness in horses and can involve multiple structures within the hoof. The T-ligament (an anatomical structure connecting the synovium of the distal interphalangeal joint, the digital flexor tendon sheath and the navicular bursa) is poorly described. Five pairs of equine cadaver distal forelimbs were collected from a slaughterhouse. Sagittal sections (medial, middle and lateral) were obtained and processed with Haematoxylin Eosin Safran, Unna's Orcein, and Picrosirius red stains. Histological assessment revealed that the T-ligament was covered by the surroundi...
Chronic Atlantoaxial Luxation Imaging Features in a Pony with Intermittent Neck Stiffness. A 17-year-old mixed breed pony was presented with intermittent neck stiffness during regular training rides in the six months preceding its admission. All parameters were within the normal range, except for an increase in heart rate (48 bpm) during the examination. Concave areas were observed at the level between the atlas and axis vertebrae (C1-C2) on both the left and right sides of the neck. Radiographs were taken of the laterolateral, left ventrodorsal oblique, and right ventrodorsal oblique projections in the cranial cervical region. The images revealed severe structural disorders, includ...
Prematurity and Dysmaturity Are Associated With Reduced Height and Shorter Distal Limb Length in Horses. The long-term effects of gestational immaturity in the premature (defined as < 320 days gestation) and dysmature (normal term but showing some signs of prematurity) foal have not been thoroughly investigated. Studies have reported that a high percentage of gestationally immature foals with related orthopedic issues such as incomplete ossification may fail to fulfill their intended athletic purpose, particularly in Thoroughbred racing. In humans, premature birth is associated with shorter stature at maturity and variations in anatomical ratios, linked to alterations in metabolism and timing of...
Cervical Epidural and Subarachnoid Catheter Placement in Standing Adult Horses. Horses underwent either cervical epidural space (CES) catheterization or subarachnoid space (SAS) catheterization while restrained in stocks, under deep sedation (detomidine and morphine) and local anesthesia (mepivacaine 2%) block. Catheters were placed under ultrasound guidance with visualization of the dura, SAS, and spinal cord between the first (C1) and second (C2) cervical vertebrae. Following sedation and sterile skin preparation, operator 1 placed under ultrasound guidance, a 6- or 8-inch Tuohy needle with the bevel oriented caudally. For CES, a 6-inch Touhy needle was used with the ha...
Quantitative sensory testing of the equine face. Quantitative sensory testing methods are now standard in the evaluation of sensory function in man, while few normal equine values have been reported. Objective: The aim of this experimental study was (a) to define the tactile sensory, mechanical nociceptive and thermal nociceptive thresholds of the equine face; (b) to assess the effect of age, sex, stimulation site and shaving; (c) to evaluate the reliability of the methods and (d) to provide reference facial quantitative sensory testing values. Methods: Method description. Methods: Thirty-four healthy Warmblood horses were used in the study....
Digit innervation of the thoracic limb of Criollo horses: Anatomical description and consequences to perineural blocks. Criollo horse breeding is an important economic activity in South America. Because of their athletic performance, these animals tend to show great incidence of musculoskeletal disorders, many of them diagnosed by means of perineural blocks. However, incorrect interpretation of these blocks may be due to anatomical differences in nerve distribution. The objective of this study was to describe the innervation of the digit region of thoracic limbs in Criollo horses, in order to improve the interpretation of tests for claudication diagnosis based on nerve block. Thirty thoracic limbs from Criollo ...
Normal regression of the internal umbilical remnant structures in Standardbred foals. Diseases affecting the internal umbilical remnant are common in foals. Ultrasound is used to diagnose abnormalities of these structures, and to monitor treatment. However, little is known about the progression of normal internal umbilical remnant regression. Objective: To document normal regression of the umbilical remnant in foals over the first 6 weeks of life. Methods: Prospective, longitudinal cohort study. Methods: Weekly ultrasound examinations were performed beginning at 1 day of age in 34 healthy Standardbred foals. The umbilical vein was measured in cross section just cranial to the...
