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.
Intramuscular distribution of fibre types in the gluteus medius of the horse: a histochemical analysis. The results from a recent study by Bruce and Schurg (1990) indicate that the gluteus medius (Gm) of the horse is a complex muscle subdivided by an internal tendinous sheet into two regions (dorsal and ventral) which may subserve different functions. In the present study, both regions were found to contain a similar proportion of histochemically-determined muscle fibre types. Fibre type composition did not generally vary over the length of the muscle at the same relative depth. In contrast, there was a significant tendency for the percentage of type I fibres to increase gradually in accordance ...
Diagnosis and prediction of cervical vertebral malformation in thoroughbred foals based on semi-quantitative radiographic indicators. Over a period of 5 years on a central Kentucky Thoroughbred stud farm 132 foals were evaluated for the presence of cervical vertebral malformation (CVM). Lateral cervical vertebral radiographs were obtained on 70 standing foals. These radiographs were evaluated semi-quantitatively and scored numerically for the presence of stenosis of the vertebral canal, enlarged physeal growth plates, caudal extension of the dorsal border of the orifice of the vertebral canal, angular fixation, delayed ossification of bone and degenerative joint disease. From these scores a total CVM score was given for each...
Giant and binucleate trophoblast cells of mammals. The cellular origin, structure, and function of trophoblastic giant cells (GC) and binucleate cells (BNC) are reviewed. Mammals in which these cells have received the greatest attention include rodents, rabbits, and humans (GCs), and ruminants and equids (BNCs). In almost all cases these cells arise from the cytotrophoblast. All are large cells and contain either two diploid nuclei (BNCs), multiple nuclei (human placental bed GCs), or single nuclei with amplified DNA content (rodent and rabbit GCs). Giant and binucleate cells typically exhibit the capacity for migration or invasion, although t...
Nucleation of the iron core occurs at the three-fold channels of horse spleen apoferritin: an EXAFS study on the native and chemically-modified protein. Extended X-ray absorbance fine structure measurements have been carried out on the initial Fe(III)-apoferritin complex at a Fe/subunit ratio of 2 in native and modified horse spleen apoferritin. Analysis of the data indicates that in the native protein the iron forms a protein-bound polynuclear cluster (Fe-Fe distance 3.4 A) with a first coordination sphere constituted by 5-6 low-Z atoms, e.g., nitrogen atoms, carboxylate-like ligands or oxo bridges between the iron atoms. Modification of Cys-126, a residue localized on the outer surface of the hydrophilic three-fold channels, with p-chloromer...
Equine fetal kinetics: Allantoic-fluid shifts and uterine-horn closures. Uterine filling by the conceptus and uterine constrictions and allantoic-fluid shifts after filling were studied by daily ultrasound examinations on Days 40 to 74 in 10 mares. Allantoic fluid was first detected at the extremities of the uterus on the following days: 1) tip of umbilical-cord horn, Day 60.0 +/-1.9 (mean +/-SEM); 2) tip of noncord horn, Day 64.8 +/-1.3; and 3) near cervix, Day 48.5 +/-1.3. Transient uterine constrictions with expulsion of allantoic fluid were detected in 37% of 271 examinations. Other end points were studied by weekly ultrasound examinations from Day 40 to term. ...
Ultrasonographic measurement of stallion accessory sex glands and excurrent ducts during seminal emission and ejaculation. Accessory sex gland and excurrent duct activity of 10 stallions was visualized with transrectal ultrasonography during seminal emission and ejaculation. First and last penile urethral contractions were defined as the start (0 sec) and end of ejaculation, respectively. Duration of ejaculation (n = 63 ejaculations) averaged 6.15 +/- 2.98 sec. Penile urethral contractions occurred an average of 6.2 +/- 2.2 times per ejaculation. Right bulbourethral glands (n = 19 ejaculations) alternated repeatedly from ovoid to flattened, irregular shapes during ejaculation. Cross-sectional area of right bulbour...
Technical note: equine skeletal preservation techniques to enhance teaching effectiveness. When the decision was made to euthanatize an acutely laminitic Thoroughbred broodmare, graduate students from the Department of Animal Sciences and Industry reconstructed the skeleton for use as a teaching tool. The reproductive and gastrointestinal tracts were removed and preserved in formalin. The hide, muscle, tendons, ligaments, and organs were removed, and the bones were boiled in water for > or = 48 h to remove all remaining tissue. After boiling, the bones were soaked in gasoline to remove fat from the marrow cavities and then soaked in a bleach/detergent mixture as a final cleaning ...
Left dorsal displacement of the colon with splenic adhesions in three horses. Three horses underwent exploratory celiotomy because of signs of acute abdominal pain. At surgery, all horses were diagnosed as having left dorsal displacement of the large colon. Each surgery was complicated by fibrous adhesions of the spleen to the body wall. All horses had previously undergone abdominal surgery for colic. In these cases, it appeared that the left large colon displaced cranially and then entered the renosplenic space from a cranial to caudal direction. Adhesions of the spleen to the body wall would prevent correction of left dorsal displacement of the large colon by the roll...
Biomechanical considerations in the treatment of navicular disease. In recent years much attention has been paid to vascular studies of the navicular bone in health and disease; however, the relative importance of these studies has overshadowed biomechanical factors which may yet prove to be of importance. This paper outlines the pertinent anatomy, and discusses current concepts in the aetiology and pathogenesis of the disease. It describes the treatment regimens which are based on biomechanical considerations and compares the results of some currently employed techniques. All aspects of navicular disease remain controversial. This paper is not intended to rev...
In vivo investigation of communication between the distal intertarsal and tarsometatarsal joints in horses and ponies. The frequency of communication between the tarsometatarsal and distal intertarsal joints was investigated in 27 horses and 12 ponies. After the injection of diluted latex into the tarsometatarsal joints using the plantarolateral approach, the horses and ponies were walked for 200 meters. Latex was found in the distal intertarsal joints of 19 of 73 tarsi (26% communication) at necropsy. In 3 tarsi, latex was also found in the proximal intertarsal and tarsocrural joints.
Characterisation of osseous bodies of the distal phalanx of foals. The distal phalanx and metacarpal physis of both forelimbs of 32 Thoroughbred foals 3-32 weeks of age were radiographed to identify those limbs with osseous bodies at a palmar process (PP) of the distal phalanx. Osseous bodies (ossicles) were identified radiographically in 19% of the foals. Sixteen of the 32 foals were selected for microradiographic and histological evaluation: 6 foals with radiographic evidence of ossicles and 10 foals without. Fourteen ossicles of the PP were observed radiographically. Ossicles were either a triangular bone fragment at the palmar aspect of the distal angle o...
Electron microscopical morphology of cytoplasmic granules from horse eosinophil leucocytes. The structure of specific granules from horse eosinophil leukocytes is still largely unknown. In this work, electron microscopical studies of horse eosinophils reveal that the large cytoplasmic granules contain an external membrane, a matrix of less density, and a dense (non crystalline) core. Round vacuolar inclusions of matrix materials were often observed within the cores. Horse eosinophil granules showed a considerable heterogeneity, and three morphological types could be identified according to structural features of the core and matrix.
Correction of patellar luxation by recession sulcoplasty in three foals. Lateral luxation of the patella in four femoropatellar joints of three foals was repaired by recession sulcoplasty and medial imbrication of the joint. One foal was euthanatized because of septic arthritis caused by incisional dehiscence, and the other two foals were normal 2 years after surgery. Recession sulcoplasty combined with medial imbrication of the joint capsule resulted in a functional femoropatellar joint and should be considered in foals affected with lateral patellar luxation.
Radiographic and microscopic correlation of diffuse interstitial and bronchointerstitial pulmonary patterns in the caudodorsal lung of adult thoroughbred horses in race training. Complete thoracic radiographic examinations were performed on 7 horses ranging in age from 24 to 60 months, followed by in-situ lung fixation. Radiographs were examined by 3 radiologists for the presence, degree and distribution of generalised pulmonary patterns within a region of interest in the caudodorsal lung. Pulmonary tissue was obtained from 12 sites within a designated volume of interest in the caudodorsal lung, corresponding to the area of interest evaluated radiographically, and examined for the presence, character and severity of microscopic lesions. Radiographic findings within the...
X-ray and primary structure of horse serum albumin (Equus caballus) at 0.27-nm resolution. The amino-acid sequence and three-dimensional structure of equine serum albumin have been determined. The amino-acid sequence was deduced from cDNA isolated from equine liver. Comparisons of the primary structure of equine serum albumin with human serum albumin and bovine serum albumin reveal 76.1% and 73.9% sequence identity, respectively. The three-dimensional structure was determined crystallographically by the molecular-replacement method using molecular coordinates from the previously determined structure of human serum albumin, to a resolution of 0.27 nm. In accordance with the primary s...
Examination of frozen cross sections of cervical spinal intersegments in nine horses with cervical vertebral malformation: lesions associated with spinal cord compression. Nine horses with clinical and radiographic findings of cervical vertebral malformation that were necropsied and examined using frozen cervical spinal cord cross sections were reviewed. Only cases with actual distortion of the spinal cord due to compression were selected. The goal of the study was to determine the morphologic features responsible for narrowing of the spinal canal and compression of the spinal cord. In individual cases, bony changes are associated with osteochondrosis and osteomyelitis of the dorsal articular facets and osteosclerosis of the dorsal cervical lamina. Soft tissue p...
Enteric neuropathy in horses with grass sickness. The degeneration of enteric neurones has been recorded in grass sickness, but the distribution of the lesions in the gut and their possible relationship with the severity of the clinical signs has not been established. Samples obtained from 11 anatomically defined sites along the gastrointestinal tract of eight control horses without gastrointestinal disease, five horses with acute grass sickness and three horses with chronic grass sickness were examined histologically. The organisation of the enteric ganglia was similar to that in other large mammalian species. Minor exceptions included the p...
Ultrasonographic appearance of ruptured peroneus tertius in a horse. Ultrasonography was a valuable diagnostic tool for examination of a ruptured peroneus tertius in a horse, because it allowed visualization of the extent of the injury and evaluation of healing prior to return of the horse to athletic activity.
Neuropeptide distributions in the colon, cecum, and jejunum of the horse. The pelvic flexure portion of the equine large colon is the proposed location of a pacemaker mechanism. This study was conducted to ascertain whether the distribution of certain putative neurotransmitters differs at the pelvic flexure compared to other sampling sites. Tissue samples were collected from the intestinal tracts of six horses. Serial sections from these samples were reacted with primary antisera specific for substance P, vasoactive intestinal polypeptide (VIP), methionine-Enkephalin, and calcitonin gene-related peptide (CGRP). The regional distribution of immunoreactive neuronal el...
The bronchial tree and lobular division of the horse lung. The lungs of five horses were examined. At present, in veterinary anatomy, the horse lung is divided into the cranial and caudal lobes by the cardiac notch on either side. In addition to these lobes, in the right lung, the accessory lobe is present. However, from the viewpoint of the bronchial ramifications, the horse lung can be divided into the cranial, middle, caudal and accessory lobes bilaterally. The horse lung has four bronchiole systems on either side, dorsal, lateral, ventral and medial. The cranial lobe is formed by the first bronchiole of the dorsal bronchiole system. The middle lob...
Lymphoplasmacytic lymphoma in a stallion. Lymphoplasmacytic lymphoma found in a 6-year-old Anglo-Arabian stallion was investigated histologically, immunohistochemically and ultrastructurally. The animal showed a large mediastinal mass and generalized lymph node involvement. The neoplastic cells were in various differentiation stages of small lymphocyte, centrocyte, centroblast, immunoblast and plasma cell. Some neoplastic cells showed positive cytoplasmic reactivity for mu and lambda chains. There were well developed rough endoplasmic reticulum (RER) and Golgi complexes in plasmacytoid cells, and slightly developed RER or a few long s...
Surgical correction of an equine deviated anterior maxilla. The surgical correction of midfacial deformities of the horse have rarely been undertaken. This article describes the successful management of a submucous cleft of the maxilla in a young colt. Details of the operative and perioperative medical and surgical management are described. The horse, now 5 years of age, has sired eight normal progeny.
