Topic:Morphology
Morphology in horses refers to the study of the form and structure of the equine body, including the skeletal, muscular, and integumentary systems. This field encompasses the examination of physical characteristics such as body conformation, limb structure, and cranial features, which can influence a horse's performance, health, and suitability for various activities or disciplines. Morphological assessments are often used in breeding programs to select for desirable traits and in veterinary evaluations to identify potential anatomical issues. This page aggregates peer-reviewed research studies and scholarly articles that explore the methodologies, findings, and implications of morphological studies in equine science.
Lamellar pathology in horses with pituitary pars intermedia dysfunction. Hoof lamellar pathology in horses with pituitary pars intermedia dysfunction (PPID) has not been described previously. Objective: To describe the histomorphometry and pathological lesions in hoof lamellar tissue of animals that had PPID with or without concurrent laminitis, with reference to age-matched controls. We hypothesised that lamellar lesions consistent with laminitis would be associated with PPID, even in animals without current or historical laminitis. Methods: Prospective case-control study. Methods: Mid-dorsal hoof histological sections were obtained post mortem from the forelimbs ...
Diseases of the Equine Urinary System. Uncommon diseases of the equine urinary system span a variety of etiologies and frequently have nonspecific clinical presentations. Because of the infrequency of equine urinary disease and inconsistencies in clinical symptoms, diagnosis and subsequent treatment of urinary disease in this species may be challenging. This article reviews various diseases of the equine urinary system, morphologies, and potential discriminating clinical and clinicopathologic presentations to aid the clinician in determining a definitive diagnosis in practice.
Improvement of development of equine preantral follicles after 6 days of in vitro culture with ascorbic acid supplementation. The aim of this study was to evaluate the effects of different concentrations of ascorbic acid (25, 50, and 100 μg/mL) in supplemented minimum essential medium (MEM+) on the development of equine preantral follicles that were cultured in vitro for 2 or 6 days. The contralateral ovaries (n = 5) from five mares in seasonal anestrus were collected from a local abattoir. Nine ovarian tissue fragments of approximately 5 × 5 × 1 mm were obtained from each animal. One fragment was immediately fixed and subjected to histologic analysis (control group; Day 0), and the other eight were placed in PBS ...
Disseminated lymphoma with large granular lymphocyte morphology diagnosed in a horse via abdominal fluid and transtracheal wash cytology. A 22-year-old Tennessee Walking Horse mare was presented to the Auburn University Large Animal Teaching Hospital with a 3-day history of lethargy, anorexia, and mild signs of colic. The mare had a several-month history of weight loss and refractory cough. Physical examination revealed an increased respiratory rate, and crackles and wheezes were heard on thoracic auscultation. Thoracic ultrasonographic examination showed disseminated, minor, bilateral comet tail-like lesions on the parietal pleural surfaces. Abdominal ultrasonographic examination was unremarkable. Trans-rectal palpation reveale...
The effect of metamizole and tolfenamic acid on canine and equine adipose-derived mesenchymal stem cells (ASCs) an in vitro research. The influences of NSAIDs (Nonsteroidal Anti-inflammatory Drugs)--non-selective metamizole and selectively-acting tolfenamic acid were estimated on morphology, ultrastructure, and cytophysiological activity of canine (Ca) and equine (Eq) adipose-derived mesenchymal stem cells (ASCs). The lowest concentration of metamizole (0.01 mg/mL) stimulated the viability and cytophysiological activity of Ca ASCs and did not affect cell morphology. Stimulated cells possessed a proper, fibroblastic shape, with large, eccentrically located nuclei. Similar effects to those observed in Ca ASCs were found in Eq ...
Setaria digitata in advancing our knowledge of human lymphatic filariasis. Setaria digitata is a filarial parasite that causes fatal cerebrospinal nematodiasis in goats, sheep and horses, resulting in substantial economic losses in animal husbandry in the tropics. Due to its close resemblance to Wuchereria bancrofti, this nematode is also frequently used as a model organism to study human lymphatic filariasis. This review highlights numerous insights into the morphological, histological, biochemical, immunological and genetic aspects of S. digitata that have broadened our understanding towards the control and eradication of filarial diseases.
Mechanoreceptors in the Anterior Horn of the Equine Medial Meniscus: an Immunohistochemical Approach. Lameness due to stifle and especially meniscal lesions is frequent in equine species. In humans, mechanoreceptors involved in proprioceptive function are well studied. Given the high incidence of meniscal injuries in horses, and the lack of information concerning them in equine menisci, our objective was to study these corpuscles in six healthy anterior horns of the equine medial meniscus, which is the most common localisation reported for equine meniscal injuries. Immunohistochemical stainings were performed using antibodies against high molecular weight neurofilaments and glial fibrillary ac...
Ultrastructure of antennal sensory organs of horse nasal-myiasis fly, Rhinoestrus purpureus (Diptera: Oestridae). Rhinoestrus purpureus (Brauer, 1858) (Diptera: Oestridae) is an economically important parasite that can cause severe nasal myiasis in equids or even attacking humans. The antennae of R. purpureus were examined using stereoscopic microscopy and scanning electron microscopy. The general morphology was provided detailedly, together with distribution, type, size, and ultrastructure of antennal sensilla. All the three antennal segments, antennal scape, pedicel, and funiculus, are interspersed by microtrichiae. Only mechanoreceptors are detected on antennal scape and pedicel. On antennal funiculus,...
Influences of age and sex on leukocytes of healthy horses and their ex vivo cytokine release. Leukocytes and their functional capacities are used extensively as biomarkers in immunological research. Commonly employed indicators concerning leukocytes are as follows: number, composition in blood, response to discrete stimuli, cytokine release, and morphometric characteristics. In order to employ leukocytes as biomarkers for disease and therapeutic monitoring, physiological variations and influencing factors on the parameters measured have to be considered. The aim of this report was to describe the ranges of selected leukocyte parameters in a sample of healthy horses and to analyse wheth...
[Morphological features of Bundleia spp. (Ciliophora: Entodiniomorphida: Buetschliidae) and ontogenesis in Bundleia Cunha and Muniz 1928]. The aim of this study was to investigate the morphological features of 7 endocommensal ciliates, B. (s. str.) postciliata, B. (s. str.) piriformis, B. (s. str.) nana, B. (C.) elongata, B. (C.) triangularis, B. (F.) dolichosoma, and B. (F.) inflata belonging to the genus Bundleia, which exist in the hindgut of 15 Rahvan horses and 15 racing horses living in the vicinity of Izmir and to investigate the ontogenesis in the Bundleia genus. Methods: Specimens were obtained from 30 horses and were fixed with 10% formalin. The morphological features of the species were investigated with the pyridinate...
Morphological and genetic characterization of an emerging Azorean horse breed: the Terceira Pony. The Terceira Pony is a horse indigenous to Terceira Island in the Azores. These horses were very important during the colonization of the island. Due to their very balanced proportions and correct gaits, and with an average withers height of 1.28 m, the Terceira Pony is often confused with a miniature pure-bred Lusitano. This population was officially recognized as the fourth Portuguese equine breed by the national authorities in January, 2014. The aim of this study was to analyze the morphology and the genetic diversity by means of microsatellite markers of this emerging horse breed. The biom...
Anatomical variation of the spinous and transverse processes in the caudal cervical vertebrae and the first thoracic vertebra in horses. There are scant data on the incidence of different anatomical variants of the equine caudal cervical spine, despite interest in cervical pathology. Objective: To identify morphological radiographic variation in the 6th and 7th cervical vertebrae and the first thoracic vertebra in horses of different breeds and to determine whether there are breed- and sex-related differences. Methods: Retrospective descriptive study. Methods: Radiographs of the cervical spine of 270 horses were assessed retrospectively. The Chi-square test, or Fisher's exact test when appropriate, was used to test for associat...
The use of novel phenotyping methods for validation of equine conformation scoring results. In this experiment, which is based on a cohort of 44 Lipizzan mares from the Austrian state stud farm of Piber, we present new statistical techniques for the analysis of shape and equine conformation using image data. In addition, we examined which strategies and procedures of image processing techniques led to a successful interpretation of the traits implemented in horse breeding programs. A total of 246 two-dimensional anatomical and somatometric landmarks were digitized from standardized photographs, and the variation of shape has been analyzed by the use of generalized orthogonal least-sq...
Relationship between the shape of the central and third tarsal bones and the presence of tarsal osteoarthritis. Osteoarthritis (OA) of the low motion joints of the tarsus, commonly termed 'bone spavin', is common in horses. Whilst the aetiology of this condition is multifactorial, it has been suggested that dorsal wedging of the central tarsal bone (CTB) and third tarsal bone (TTB) may predispose to the development of this disease. The aim of this study was to investigate the relationship between tarsal bone conformation and osteoarthritis of the proximal intertarsal (PIT), distal intertarsal (DIT) and tarsometatarsal (TMT) joints. It was hypothesised that wedging of the CTB and TTB would be associated ...
Expression of surface platelet receptors (CD62P and CD41/61) in horses with recurrent airway obstruction (RAO). Recurrent airway obstruction (RAO) is an allergic disease of horses similar to human asthma, which is characterized by airway inflammation and activation of neutrophils, lymphocytes and platelets. Platelet activation and an increase in circulating platelet-leukocyte aggregates may lead to airway remodeling. The aim of this study was to investigate platelet status in RAO-affected horses based on the platelet morphology and platelet surface expression of CD41/61 and CD62P. Ten RAO-affected horses and ten healthy horses were included in this study. Blood samples were obtained to determine the pla...
Anatomic and histologic features and ultrasonographic appearance of the collateral ligaments of the metacarpophalangeal and metatarsophalangeal joints in cadaveric limbs from horses without lameness. To describe the anatomic and histologic features of the collateral ligaments (CLs) of the metacarpophalangeal (MCP) and metatarsophalangeal (MTP) joints in cadaveric limbs obtained from nonlame horses and to compare the histologic findings with the ultrasonographic appearance of the CLs. Methods: Medial and lateral CLs of the MCP and MTP joints of 28 limbs (16 forelimbs and 12 hind limbs) from 9 adult nonlame horses euthanized for reasons unrelated to the study. Methods: 26 limbs of 8 horses were examined by ultrasonography immediately after euthanasia. Postmortem gross and histologic examinat...
Use of density centrifugation for delayed cryopreservation of stallion sperm: perform sperm selection directly after collection or after storage? Equipment for cryopreservation of stallion sperm is not always available. In such cases, diluted semen can be shipped to a facility for later cryopreservation. The aim of this study was to evaluate if selection of sperm via density centrifugation yields higher survival rates when cryopreservation is to be delayed (i.e. carried out after 1 day of storage at 5°C). Two-layer iodixanol as well as single-layer Androcoll density centrifugation were tested and compared with samples prepared with standard centrifugation. Special emphasis was placed on comparing centrifugation on the day of semen coll...
Esophageal Dysfunction in Friesian Horses: Morphological Features. Megaesophagus appears to be more common in Friesian horses than in other breeds. A prevalence of approximately 2% was observed among Friesian horses presented to the Wolvega Equine Clinic and the Utrecht University Equine Clinic. In this study, morphologic changes in the esophagi of Friesian horses with megaesophagus were compared with those of 6 control horses. Of 18 horses with clinically observed megaesophagus, only 12 animals had esophageal dilation at necropsy, usually involving the thoracic portion. Muscular hypertrophy of the distal esophagus was present in only one-third of the affecte...
Changes in platelet morphology and function during 24 hours of storage. For in vitro studies assessing the interaction of platelets with implant materials, common and standardized protocols for the preparation of platelet rich plasma (PRP) are lacking, which may lead to non-matching results due to the diversity of applied protocols. Particularly, the aging of platelets during prolonged preparation and storage times is discussed to lead to an underestimation of the material thrombogenicity. Here, we study the influence of whole blood- and PRP-storage times on changes in platelet morphology and function. Blood from apparently healthy subjects was collected according...
Pathology of Natural Cases of Equine Endocrinopathic Laminitis Associated With Hyperinsulinemia. Laminitis in equids is a clinical syndrome usually associated with systemic disease. Endocrinopathies recently have been recognized as the most common cause of laminitis, with hyperinsulinemia playing a key role. Descriptions of laminitis-associated lesions have been confusing due to the wide range of experimental models used, failure of adequate clinical documentation for naturally occurring cases, lack of separate analysis of inflammatory and endocrinopathic laminitis, and uncertainty regarding normal morphological variation of lamellae. In this study, lamellar morphology and pathology were ...
Molecular and morphological comparison of two different types of Habronema muscae (Nematoda: Habronematidae) in horse. Habronema muscae is a spirurid nematode that undergoes developmental stages in the stomach of equids, causing chronic catarrhal gastritis. Despite preceding investigations have developed polymerase chain reaction (PCR)-based assays for molecular diagnosis, we aimed to assess the applicability of cytochrome c oxidase subunit 1 (cox1) sequences to identify the H. muscae infection and to assess the level of intraspecific variations in this parasite obtained from affected horses in Southern Iran. According to the morphological characterizations, two different isolates of H. muscae were identified....
The embryogenesis of the equine femorotibial joint: The equine interzone. Articular cartilage regeneration is the focus and goal of considerable research effort. Since articular chondrocytes descend from a distinct cohort of progenitor cells located in embryonic nascent joints (interzones), establishing the timing of equine interzone formation is an essential first step towards understanding equine joint and articular cartilage development. Objective: To establish the time frame during which the equine femorotibial interzone forms. Methods: Descriptive anatomical study. Methods: Equine embryos were harvested at 37 (E37), 40, 42, 45, 50 and 65 days' gestation. The fe...
Equine sarcoid: In situ demonstration of matrix metalloproteinase expression. Sarcoids are the most prevalent equine skin tumours and remain a therapeutic challenge due to their differing clinical morphology, local aggressive behaviour, and high recurrence following surgical treatment. In vitro, sarcoid derived fibroblasts are invasive and express matrix metalloproteinase (MMP) -1, -2 and -9. It was hypothesised that the MMPs produced by neoplastic cells play a role in both their local invasiveness and interaction with the overlying epidermis (picket fence formation). The objective of this morphological study was to investigate the local behaviour and in situ MMP expres...
Membrane vesicles mediate pro-angiogenic activity of equine adipose-derived mesenchymal stromal cells. Multipotent mesenchymal stromal cells (MSCs) have attracted a great deal of interest, due to several distinctive features, including the ability to migrate to damaged tissue and to participate in tissue regeneration. There is increasing evidence that membrane vesicles (MVs), comprising exosomes and shedding vesicles, represent a key component, responsible for many of the paracrine effects of MSCs. The aim of the present study was to establish whether equine adipose-derived MSCs (E-AdMSCs) produce MVs that are capable of influencing angiogenesis, a key step in tissue regeneration. A morphologic...
Morphology, Morphometry and Spatial Distribution of Secondary Osteons in Equine Femur. A high number of differences exist in bone histological features depending on the species, breed, age and bone. Moreover, osteon distribution may vary in the different sides of a bone as a consequence of different biomechanical strains. The aim of this work was to study the distribution and morphology of osteons in different sides of the equine femoral diaphysis with the attempt to correlate them to the main strains operating on them. The following parameters of secondary osteons and Haversian canals were measured in the transverse sections of diaphyses: perimeter, area, minimum and maximum di...
Morphologic and morphometric features of the calcaneal insertions of the superficial digital flexor tendon in the horse. Accurate description of the calcaneal insertions of the superficial digital flexor tendon (SDFT) is lacking and inconsistent. The aim of this study was to undertake morphologic and morphometic evaluations of these structures to assist in elucidating their functional and pathogenic roles in displacement of the SDFT from the calcaneal tuber. Methods: Dissections were performed on 10 normal cadaveric hindlimbs. The anatomy was photographed to allow measurements at repeatable locations and differences in SDFT dimensions at the various locations were compared using a paired student t-test. Results:...
Histomorphometric parameters and fractal complexity of the equine placenta from healthy and sick foals. Computer-based digital image analysis of tissue samples shows promise both to reduce the subjectivity of traditional manual tissue assessments and potentially to shorten the time required to analyze each sample. The present study used digital image analysis to investigate the histomorphometric parameters and fractal complexity of the equine placenta from healthy and sick foals. We hypothesized that the placentas of sick foals could have a different growth pattern and complexity that could be objectively estimated by their fractal dimension (FD). Fourteen placentas from 30 mares were selected i...
Morphometric examination of the equine adult and foal lung. To understand the mechanisms of airway inflammation associated with equine diseases such as Rhodococcus equi infection, we must identify baseline "normal" structural characteristics of the horse lung. To develop a detailed understanding of the morphology of the horse lung, we adapted and applied stereological methods to the lungs from healthy adult horses (N = 4) and 1-day (N = 5) and 30-day (N = 5) old foals. The left lung was fixed in situ by intrabronchial instillation of glutaraldehyde/paraformaldehyde fixative at 25 cm H2 O column and sampled using a fractionator design follow...
Dermatological and morphological findings in quarter horses with hereditary equine regional dermal asthenia. Hereditary equine regional dermal asthenia (HERDA) is an autosomal recessive disorder affecting quarter horses (QHs); affected horses exhibit characteristic skin abnormalities related to abnormal collagen biosynthesis. Objective: To characterize the thickness and morphological abnormalities of the skin of HERDA-affected horses and to determine the interobserver agreement and the diagnostic accuracy of histopathological examination of skin biopsies from horses with HERDA. Methods: Six affected QHs, confirmed by DNA testing, from a research herd and five unaffected QHs from a stud farm. Methods:...
Patterning and post-patterning modes of evolutionary digit loss in mammals. A reduction in the number of digits has evolved many times in tetrapods, particularly in cursorial mammals that travel over deserts and plains, yet the underlying developmental mechanisms have remained elusive. Here we show that digit loss can occur both during early limb patterning and at later post-patterning stages of chondrogenesis. In the 'odd-toed' jerboa (Dipus sagitta) and horse and the 'even-toed' camel, extensive cell death sculpts the tissue around the remaining toes. In contrast, digit loss in the pig is orchestrated by earlier limb patterning mechanisms including downregulation of...