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.
Congenital atresia of the parotid duct in a horse. Congenital anomalies of the equine salivary glands and their ductal systems are rare. In man, parotid duct atresia is thought to be due to a congenital malformation of the first branchial arch. One horse with unilateral parotid salivary duct atresia is described. Imaging modalities available for accurate diagnosis, and treatment options, are reviewed.
Evaluation of different projections for radiographic detection of tarsal degenerative joint disease in Icelandic horses. Radiographs from 196 tarsi in 98 Icelandic horses were evaluated to compare the accuracy of four different projections in detecting radiographic signs of degenerative joint disease in the distal tarsus. The extent and localization of tarsal degenerative joint disease found in one projection when reading all four projections of the same tarsus together was compared with the combined findings from all four projections. The results of reading individual radiographic projections without knowledge of the other three projections was also evaluated. Degenerative joint disease was detected most freque...
Computed tomographic evaluation of Finnhorse cadaver forefeet with radiographically problematic findings on the flexor aspect of the navicular bone. Computed tomography (CT) was performed on 12 Finnhorse cadaver forefeet with known radiographic changes in the navicular bone (poor corticomedullary junction, irregular appearance of the flexor central eminence, uneven or unequal thickness of the flexor cortex, and/or irregular outline of the proximal or distal flexor margin). The purpose was to confirm the radiographic findings and to investigate if further information of the flexor aspect of the bone could be gained with CT. In CT, the midsagittal outline as well as the internal structure of the bones varied greatly. Different combinations o...
Correlation between surface electromyography and kinematics of the hindlimb of horses at trot on a treadmill. The purpose of this study was to demonstrate the feasibility of surface electromyography in the horse and to correlate electromyographic activity with kinematic data. Surface electromyography of seven hindlimb muscles was recorded in five horses at trot on a treadmill. Simultaneously, kinematic analysis of the hindlimb was performed using a three-dimensional system and a unidirectional accelerometer was attached to the hoof. Electromyographic activities of the gluteus medius, vastus lateralis and two parts of the biceps femoris started in the late part of the swing phase and ended in the late ...
Equine dental disease part 1: a long-term study of 400 cases: disorders of incisor, canine and first premolar teeth. A review of 400 horses referred because of dental disorders showed 44 cases to suffer from primary disorders of their incisors and 11 from canine or 1st premolar teeth disorders. The remaining 345 horses suffered from primary disorders of the cheek teeth. Disorders of incisors included traumatic damage to teeth and their supporting bones, retained deciduous, displaced and supernumerary incisors; brachygnathia and abnormalities of wear, with most of the latter disorders being secondary to primary disorders of the cheek teeth Only 3 cases of apical infection of incisors were recognised. Most cas...
Horse vision and an explanation for the visual behaviour originally explained by the ‘ramp retina’. Here we provide confirmation that the 'ramp retina' of the horse, once thought to result in head rotating visual behaviour, does not exist. We found a 9% variation in axial length of the eye between the streak region and the dorsal periphery. However, the difference was in the opposite direction to that proposed for the 'ramp retina'. Furthermore, acuity in the narrow, intense visual streak in the inferior retina is 16.5 cycles per degree compared with 2.7 cycles per degree in the periphery. Therefore, it is improbable that the horse rotates its head to focus onto the peripheral retina. Rather...
Radiological measurements from the feet of normal horses with relevance to laminitis. Lateromedial radiographic projections were made from the feet of 25 normal horses and 3 angles and 3 distances were measured. From these, normal ranges of calculated variables were obtained. The width and length of each foot and the height of the horse at the withers was also measured. In view of its possible importance in clinical laminitis, particular attention was paid to 'founder' distance (D). This is the vertical distance between the proximal limit of the dorsal hoof wall and the proximal limit of the extensor process of the distal phalanx. There were significant differences between bree...
Lameness associated with the bicipital bursa in an Arab stallion. Severe, chronic lameness in the left forelimb of a five-year-old Arab stallion was localised to the bicipital bursa by local anaesthesia and gamma scintigraphy. Radiographic and ultrasonographic examinations of the proximal humeral tubercles and bicipital bursa revealed new bone production in the region of the intertubercular grooves and irregularities in the density of the soft tissues of the bicipital tendon and bursa. An endoscopic examination of the bicipital bursa with a standard arthroscope under general anaesthesia was a useful diagnostic procedure. The stallion was euthanased, and mark...
Jejunoileal incarceration and strangulation through a splenic defect in a mare. A 6-year-old, standardbred mare was presented for colic of 12 h duration. Transrectal palpation revealed intestinal distension of unknown cause. The mare was euthanized. At necropsy, segmental jejunoileal incarceration and strangulation through an opening in the spleen was observed. This opening was considered to be a congenital defect.
Three-dimensional ultrastructure of synoviocytes in the horse joint as revealed by the scanning electron microscope. The synovial membrane displays a superficial cellular lining composed of two types of synoviocytes: "absorptive" macrophages (type A cells) and "secretory" fibroblast-like cells (type B cells). The types are intermingled and extend a variety of processes, rendering the cellular architecture of the synovial membrane difficult to visualize. Previous electron microscopic and histochemical studies failed to demonstrate the entire shape of synoviocytes, except our immunohistochemical study for protein gene product 9.5 in the horse joint. The present SEM study is the first to demonstrate the three-d...
Intramuscular desmoid tumor (musculoaponeurotic fibromatosis) in two horses. Intramuscular desmoid tumors (musculoaponeurotic fibromatosis) were discovered in two young adult horses. The tumor in one horse was in the lateral cervical musculature, and that in the second horse occurred in the pectoral musculature. Histopathologic features were similar in both horses and included proliferation of fibroblasts and cells expressing muscle actin (myofibroblasts), with extensive dissecting fibrosis within muscle. These features are similar to those of desmoid tumors in humans, particularly those also known as musculoaponeurotic fibromatosis. Dissection of these lesions reveale...
Laryngeal movements during the respiratory cycle measured with an endoscopic imaging technique in the conscious horse at rest. A video-laryngoscopic method, implemented with an algorithm for the correction of the deformation inherent in the endoscope optical system, has been used to measure the dorsoventral diameter (Drg) and the cross-sectional area (CSArg) of the rima glottidis in five healthy workhorses during conscious breathing at rest. Simultaneous recording of the respiratory airflow was also obtained in two horses. Drg measured 82.7 +/- 4.5 mm (mean +/- S.D.) independently of the respiratory phase, and did not differ from the measurement in post-mortem anatomical specimens of the same horses. CSArg ranged from...
[“This helps; this is good”. Horse books of Tibetan Himalayas]. The present paper summarizes our recent investigations of the so-called horse books from the High Himalayas in Nepal. These books are written in tibetan language and are essentially dealing with hippology and hippiatry and to a lesser extent with topics such as pharmacology, anatomy, methods of diagnosis, divination and magical practices for horse races. The therapeutic methods of treatment in tibetan veterinary medicine are guided by the concepts of human medicine which, on the one hand, are related to the Ayurvedic System, on other hand, to the Traditional Chinese Medicine. Concerning the st...
The mechanisms and consequences of structural failure of the foot. Many of the difficulties in managing the horse with chronic laminitis are associated with the foot's mechanical failure. The occurrence of digital collapse cannot be viewed in isolation as the primary therapeutic focus. The circulatory, metabolic, and growth pattern changes induced by the foot's mechanical collapse often serve as major limiting factors to successful rehabilitation. From the discussion above, it is obvious that a significant amount of research is needed to better understand the biomechanical pathologies of the failed foot.
Trimming and shoeing the chronically affected horse. Several of the technical approaches applied to the foot overlap with regard to intent. Frog or solar support, for example, may be provided either to stabilize the distal phalanx within the hoof capsule or in an effort to unload regional pain arising from the solar surface of the foot. It is likewise obvious that some techniques such as lowering the heels to achieve phalangeal realignment and raising the heels to relieve deep digital flexor tendon tension are contradictory. In these instances, it is not that one technique is always correct but that differences exist among horses. Currently, it ...
Clinical presentation, diagnosis, and prognosis of chronic laminitis. This article focuses on the initial assessment of the horse affected with chronic laminitis. Variations in the clinical presentation and primary considerations in making a differential diagnosis are included. The elements of a clinical history essential to sound, therapeutic management, and prognosis are summarized. The physical and radiographic assessment of the digital lesions and diagnostic approaches to the common systemic aspects of the disease are presented and discussed.
Clinical presentation, diagnosis, and prognosis of acute laminitis. The purpose of this article is to describe the clinical features present in the patient affected with acute laminitis. The variations in the stance and characteristic lameness of the acute disease are described in relation to the disease severity and limb involvement. The elements of establishing a diagnosis including clinical history, physical and radiologic evaluation, and differential diagnosis are discussed. Difficulties and criteria used in establishing a prognosis of the acute phase patient are defined.
The digital pathologies of chronic laminitis. This review indicates that the patient-to-patient uniqueness commonly seen in chronic laminitis represents the variable presence of the digital pathologies. Although some degree of mechanical failure is always present, the secondary metabolic and growth dysplasias, vascular pathologies, and sepsis may or may not be evident. The presence and severity of these pathologies appear to have a more significant impact on the prognosis of individual cases than does the displacement of the distal phalanx. It should be reiterated that it is often the combined presence of these individual pathologies that...
The pathophysiology of chronic laminitis. Pain and anatomic pathology. The potential pathologic manifestations of chronic laminitis are just as varied, and possibly more so, than the list of possible inciting agents of the disease itself. The extent to which rehabilitation and return to normal function can be attained, cannot always be accurately determined by physical examination. It should be remembered that significant physiologic and pathologic alterations occur in chronic laminitis; thus, even if radiographically the patient returns to a normal appearance, residual morphologic and structural defects are likely to remain.
Identification of an ossicle associated with the palmar aspect of the carpus in the horse. An ossicle associated with the palmar aspect of the carpus is described in five horses. The size of the ossicle varied from 3 x 4 mm to approximately 12 x 10 mm. The ossicles were located at the junction of the proximal and distal rows of carpal bones, between the palmaromedial aspect of the fourth carpal bone and the ulnar carpal bone. In 3 horses they were bilateral, in one horse unilateral, and only one limb was examined in the remaining horse. In all horses it was an incidental finding and not regarded to be a pathologic entity.
A congenital malformation of the maxilla of a horse. A 1-month-old male American Paint Horse was evaluated for a hard swelling on the right side of the maxillary region. On radiographs there was a large, expansile outpouching of the right maxillary bone between the second and third premolar teeth. Computed tomography further characterized the expansile lesion to have a soft tissue component and to originate in the region of a caudal maxillary tooth. Surgical reconstruction of the defect was unsuccessful and the animal was euthanetized. Based on failure to find histopathologic evidence of a neoplasm or cyst, the diagnosis was a congenital malform...
Persistent vitelline vein in a foal. A three-day-old foal died from intestinal strangulation due to a remnant of vitelline vein which extended between the umbilicus and the portal vein. The strangulating vein was identified on the basis of its morphological and histological structure. This finding, which is the first reported case of a persistent vitelline vein in a horse, is discussed in relation to the normal development and involution of the vitelline circulation.
Characterisation of the type and location of fractures of the third metacarpal/metatarsal condyles in 135 horses in central Kentucky (1986-1994). The objective of this retrospective study was to provide a detailed description of the characteristics of condylar fractures represented in a population of 135 horses who sustained 145 fractures. Records and radiographic studies were examined. Fifty-nine percent of the horses were male and the majority Thoroughbreds. The distribution of fractures was 37% incomplete-nondisplaced, 30% complete-nondisplaced and 32% complete-displaced. The right front was more likely to sustain a complete-displaced fracture, whereas the left front was more likely to sustain an incomplete-nondisplaced fracture. For...
Equine castration: review of anatomy, approaches, techniques and complications in normal, cryptorchid and monorchid horses. Complications associated with equine castration are the most common cause of malpractice claims against equine practitioners in North America. An understanding of the embryological development and surgical anatomy is essential to differentiate abnormal from normal structures and to minimise complications. Castration of the normal horse can be performed using sedation and regional anaesthesia while the horse is standing, or under general anaesthesia when it is recumbent. Castration of cryptorchid horses is best performed under general anaesthesia at a surgical facility. Techniques for castratio...
