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.
Samuelson D, Smith P, Brooks D.The iridocorneal angle of the horse was anteriorly lined by a pectinate ligament, consisting of several layers of vertically oriented collagenous beams, that were interrupted by a network of extracellular spaces. The anterior chamber angle consisted mostly of a large uveal trabecular meshwork that was composed of widely-spaced, thick trabeculae. These trabeculae were attached in part posteriorly to extensions of the ciliary body musculature and anteriorly inserted into the prominent pectinate ligament. The corneoscleral trabecular meshwork was shaped hemiobovately and formed the external bound...
Buchwalder R, Schuster R.For the first time findings of Setaria equina (Abildgaard, 1789) in horses are reported from the German Democratic Republic. The nematodes, located in the peritoneum, were discovered in the course of autopsy. Based on a thorough analysis of the international literature, the paper discusses geographical distribution, morphology, cycle and diagnosis of this nematode as well as clinical symptoms mainly caused by the stages of the larvae.
Liebler EM, Gerhards H, Denkhaus M, Pohlenz J.Infections with Micronema deletrix are described sporadically in humans and horses. This case report describes the infection with Micronema deletrix in a horse. The animal was sent to the clinic because of recurrent colic. On rectal palpation a mass was detected in the area of the right kidney and the horse was destroyed on its owners request. At slaughter a greatly enlarged right kidney interspersed with numerous white nodules was found. Histological examination revealed a granulomatous nephritis with numerous sections of nematodes. Based on their morphology and size, they were identified as ...
Saaranen M, Suistomaa U, Vanha-Perttula T.Selenium (Se) and glutathione peroxidase (GSH-Px) were determined from the seminal plasma samples and spermatozoa of human and four different animal species. The human sperm Se concentration was 1.8 +/- 0.8 micrograms/g dry weight, which was about half of that in the bull. Abnormal sperm morphology and motility correlated with low sperm Se content. The volume of sperm mitochondrial sheath in human, bull and stallion was measured using transmission electron microscopy. In these species the sperm Se content was highly correlated with the volume of mitochondria. Among the five species studied, th...
Wheeler SJ, Plummer JM.Transverse sections of the lateral palmar nerve from a group of horses free from neuromuscular disease were assessed quantitatively, with emphasis on differences in the fibre population related to age. Morphometric analysis of the population of myelinated and unmyelinated fibres was performed. Changes were identified, there being a loss of larger myelinated fibres in older horses. The relationship of myelin thickness to axon diameter and the unmyelinated fibre population did not alter with age. The lateral palmar nerve is suitable for biopsy and electrophysiological study in the horse, but age...
López ML, Grez P, Gribbel I, Bustos-Obregón E.The epididymis of stallion castrated during the breeding and non breeding seasons were subdivided into six regions and their ultrastructural and cytochemical characteristics were studied in order to provide a better understanding of the structure-function relationship of this androgen target organ. Even when the stallion has been postulated to be a seasonal breeder, our results do not show significant ultrastructural or cytochemical differences in both seasons. The pseudostratified epithelium is composed mainly of principal and basal cells and intraepithelial lymphocytes. The principal cells s...
Kozawa Y, Mishima H, Sakae T.During the evolution of the Equoidea, the histological structures of the teeth have become more complex as the molars have become hypsodont in form. The straight Hunter-Schreger bands of Hiracotherium have evolved into a more complex pattern in Equus. The enamel prisms changed from an arched form (about 5μm in diameter) with an alternating pattern in Hiracotherium to an oval form (about 2 μm width) arranged in straight rows in Equus. In Equus the rows of prisms are separated by interprismatic sheets. This pattern may have increased the architectural strength of the enamel, and is related to ...
Ford TS, Ross MW, Orsini PG.To study communications and boundaries of the middle carpal and carpometacarpal joints of the horse, 50 forelimbs were obtained from fresh cadaver specimens. Blue latex solution (20 +/- 2.5 ml) was injected into the middle carpal joint, and the specimens were frozen in extension. Frozen specimens were cut into 1-cm sagittal sections from the middle of the radius to the middle of the metacarpus. The communications between the middle carpal and carpometacarpal joints and the presence, length, and position of the distopalmar outpouchings of the carpometacarpal joint were recorded. The middle carp...
Kayar SR, Hoppeler H, Mermod L, Weibel ER.Individual mitochondria were reconstructed from ultrathin serial sections of selected muscle fibers in the M. semitendinosus of a horse, over a length of nearly two sarcomeres. Mitochondria were found to be highly variable, with size and complexity of single mitochondria increasing with the fractional part of a fiber occupied by mitochondria. In fibers with a mitochondrial volume density of less than 4%, corresponding to the mitochondrial content of fast-twitch glycolytic fibers, mitochondria were generally rather simple cylindrical shapes, oriented parallel to the myofibrils. In fibers with a...
Kelly CM, Hoyer PB, Wise ME.Dispersed horse luteal cells were used to evaluate the ability of horse LH, hCG and PMSG to stimulate progesterone secretion in vitro. Morphological characterization of these cells before gonadotrophin stimulation indicated the presence of two populations of cells based on cell diameters. In luteal cells incubated as suspended cells, horse LH and hCG stimulated (P less than or equal to 0.05) progesterone production at all levels of treatment. Stimulation of progesterone secretion by hCG was greater (P less than or equal to 0.05) than by horse LH over the range of concentrations utilized. When ...
Simpson RM, Hodgin EC, Cho DY.Necropsy of a chronically lame 16-year-old thoroughbred gelding revealed granulomatous osteomyelitis and polyarthritis due to a widely disseminated infection by Micronema deletrix. Diagnosis was based upon the nematode's morphology with its characteristic rhabditiform oesophagus. Granulomata, often containing one or more centrally located M. deletrix, were observed histologically in sections prepared from femur, kidney, stomach, lung, adrenal gland and sublumbar lymph nodes. Neither verminous meningo-encephalitis nor cephalic granulomata, which are the more commonly described lesions, was foun...
MacDonald AA, Fowden AL, Silver M, Ousey J, Rossdale PD.Hearts from 24 foals were studied; 10 were from foetuses ranging in gestational age from 230 to 322 days and 14 were from newborn and young foals aged between birth and 17 days. The foramen ovale and associated vena caval and atrial structures were examined by scanning electron microscopy. Additional observations were made by light and transmission electron microscopy. A tube-like flap of tissue was observed, extending from the aperture in the caudal vena cava to the lumen of the left atrium. In the younger foetuses, the distal end of this tube was covered with a thread-like network of tissue....
Machida N, Yasuda J, Too K, Kudo N.The obliteration processes of the ductus arteriosus of equine foetuses and newborn foals were studied morphometrically and histologically. The length, internal and external diameters and circumference of the ductus in equine foetuses increased progressively and linearly up to 310 days with advancing foetal age, but the values, especially the internal diameter, decreased from 320 to 330 days. After birth, the ductal measurements decreased gradually and ductal closure was found in three of 14 foals examined on the first day post partum, in two of six on the second day and in nine of nine on the ...
Machida N, Yasuda J, Too K.A morphometric study of hearts in 81 equine foetuses, ranging in age from 190 to 330 days of foetal age, and in 26 newborn foals is reported. The mean weight, external dimensions, ventricular wall thickness and circumference of the atrio-ventricular orifice were measured. Features of the main associated vessels of the heart were also recorded. All cardiac measurements of foetuses increased linearly throughout the latter half of pregnancy and were highly correlated with foetal age. This linear growth pattern was also found in the parameters of the associated arterial trunks. The ratio of the ri...
Snyder JR, Olander HJ, Pascoe JR, Holland M, Kurpershoek CJ.Morphologic changes that develop sequentially in the large colon during experimentally induced ischemia were documented in 14 halothane-anesthetized horses. Colonic ischemia was induced by 4 types of vascular occlusion, 24 cm proximal and distal to the pelvic flexure. The effect of transmural (colonic wall) vascular compression combined with either venous occlusion (3 horses, group A) or venous and arterial occlusion (3 horses, group B) of the colonic vessels was studied for 1, 2, and 6 hours of occlusion. Also observed was the effect of reperfusion for 0.5 hour after release of the clamps for...
Enders AC, Lantz KC, Liu IK, Schlafke S.Twelve blastocysts, collected 7-12 days after ovulation (Day 0), were examined by light and electron microscopy to investigate the nature of the relationship of the polar trophoblast (Rauber's layer) to the inner cell mass. On Day 7, the polar trophoblast was intact and formed a flattened layer overlying the epiblast cells of the inner cell mass. As blastocysts enlarged to greater than 1 mm in diameter, small discontinuities appeared in the polar trophoblast, where epiblast cells intruded onto the surface. At this time, trophoblast cells adhered closely to adjacent and underlying epiblast cell...
Almahbobi G, Papadopoulos V, Carreau S, Silberzahn P.Two ultrastructurally distinct types of Leydig cells were observed in the equine testis. Whereas the adult testis exhibited both postpubertal and adult Leydig cells, the testis of the pubertal horse contained only the postpubertal type, and that of the aged horse contained only the adult type. However, Percoll-purified testicular preparations from pubertal, adult, and aged horses all exhibited two distinct Leydig cell populations. The quantitative distribution and the functional characteristics of these Leydig cell populations (ability to bind human chorionic gonadotropin [hCG] and increase of...
Kirkpatrick CE, Saik JE.Ciliated protozoa of several morphological types were found in the colonic tissue of 8 horses, mostly immature Standardbreds. Most of the protozoa observed appeared similar to those normally found as commensals in the equine large intestinal lumen. In all cases, organisms were located in the lamina propria; organisms were also found in the submucosa of 2 horses. The association of colonic disease with the presence of intramural ciliates was unclear.
de Paz Cabello P, Chamorro CA, Sandoval J, Fernandez M.The mechanical papillae of the horse and cow were studied by scanning electron microscopy in order to determine their morphostructural characteristics and the differences between the two species. The horse has only thin, small and interlaced filiform papillae, while the cow shows robust and more ordered filiform papillae. Furthermore, the cow tongue presents conical and lenticular papillae surrounded by a papillary groove. A characteristic distribution of stratified scales and channeled tracts is observed in conical and lenticular papillae but not in the filiform papillae. The morphostructural...
Cozzi B, Pellegrini M, Droghi A.The structure and histochemical properties of neuromelanin in the Substantia nigra of the horse were studied by light and electron microscopy. Morphological, histochemical and cytochemical evidences showed the presence of a melanin component in some pigment granules, even if a large quantity of granules displayed only the properties of lipofuscins. Pigment formation in the neurons of the Substantia nigra of the horse may take place through the tyrosine-tyrosinase enzymatic pathway, as shown by positive Dopa-reaction. The results obtained were discussed in reference to the possible use of melan...
Boudouard M, Giudicelli J, Sudaka P.A rapid method for preparation of brush border membrane vesicles from a large amount of horse kidney cortex is described. Self-orienting Percoll-gradient centrifugation minimized contamination by microsomal membranes. The characteristics of this preparation were checked by electron microscopy and measurement of L-alanine uptake.
Allen D, White NA, Tyler DE.The morphologic effects of induced intraluminal hydrostatic pressures (IHPs) of 0, 9, and 18 cm H2O were evaluated in 33 isolated equine jejunal segments. Fifteen segments were distended with Tyrode's solution for 1 hour and nine segments for 4 hours. Tyrode's solution was added as needed to maintain the prescribed pressures. Nine other segments were left undisturbed for 4 hours after the initial distention period. On decompression of the intestinal segments, progressive peristaltic contractions resumed in all segments. Evaluation of intestinal sections by light microscopy and transmission ele...
Gold JJ, Heath IB, Bauchop T.Vegetative and reproductive stages of Caecomyces equi gen. nov., sp. nov. isolated from the horse caecum were examined by light and electron microscopy. This organism, which is similar to isolates known as Sphaeromonas communis, produces uniflagellate, uninucleate zoospores whose perikinetosomal structures, i.e. circumflagellar ring, spur, struts and scoop, are similar in many respects to those described in species of Neocallimastix. Microtubular roots extend basally from the spur and associate with hydrogenosomes and the nucleus. Another group of microtubules radiates laterally in a fan-shape...
Illera JC, Hamlin RL, Illera M.Bipolar and unipolar limb leads and unipolar thoracic lead ECG were obtained from 100 male crossbred horses. P-wave morphologic features were classified according to positivity negativity and monopolarity dipolarity, and the percentage of horses that had P waves of a given morphologic class in each lead was calculated. P-Wave morphologic features of 4 precordial leads were most uniform, with greater than 80% of the horses having a single configuration.
Pfeiffer CJ, Murray MJ, Fainter L.The granular columnar epithelial cell of the equine dorsal large colon has been studied by transmission electron microscopy and X-ray microanalysis. Particular attention was focused on nuclear bodies commonly observed as central clusters of spherical, electron-dense inclusions within the nucleus. Ultrastructural morphology as well as X-ray microanalysis spectra reveal great similarity between colonic nuclear bodies and the numerous small granules of the apical cytoplasm in these epithelial cells. X-ray spectra of these cells were distinct from those of goblet cell mucous granules and mast cell...
Ball BA, Hillman RB, Woods GL.To test the hypothesis that an abnormal uterine environment was a cause of early embryonic loss in subfertile mares, morphologically normal embryos were transferred to normal mares (n = 20) and subfertile mares (n = 20), and embryo survival rates were compared. Embryos were recovered nonsurgically at Days 7 to 8 postovulation and transferred surgically to normal and subfertile mares that had ovulated on the same day or within 2 d after a donor. Survival of transferred embryos was monitored by ultrasonography of the recipient mare's uterus from Day 9 through Day 28 postovulation. There were no ...
Shipton WA.The equine phycomycotic agent known commonly as Hyphomyces destruens or occasionally as Pythium gracile, is described as a new species Pythium destruens. Separation is on the basis of morphological features, temperature growth profiles, esterase/lipase activity, and carbohydrate utilization ability. P. diclinum (synonymous with P. gracile sensu Middleton) showed minor differences in vesicle, oospore and oogonium size from P. destruens. P. destruens grew at 40 degrees C on corn meal agar and hydrolysed esters of lauric and oleic acids. These abilities were not displayed by P. diclinum, but this...
Richardson LM, Gordon J, Davila C, Chamoun-Emanuelli AM, Zdyrski C, Whitfield-Cargile CM.Gastrointestinal (GI) disease is a major cause of morbidity and mortality in horses, with disruption of the intestinal epithelial barrier playing a central role in disease pathogenesis. A deeper understanding of the molecular and functional properties of the equine intestinal barrier is essential to improve diagnostics and therapeutics. While intestinal organoids have emerged as a promising tool for modeling GI physiology and disease, equine-specific data remain limited. Existing studies vary in methodology and often lack functional characterization, particularly across different intestinal re...
Nunez R, Gomes-Keller MA, Schwarzwald C, Feige K.RATIONALE: Thrombocytopenia is a platelet associated process that occurs in human and animals as result of i) decreased production; ii) increased utilization; iii) increased destruction coupled to the presence of antibodies, within a process know as immune-mediated thrombocytopenia (IMT); or iv) platelet sequestration. Thus, the differentiation of the origin of IMT and the development of reliable diagnostic approaches and methodologies are important in the clarification of IMT pathogenesis. Therefore, there is a growing need in the field for easy to perform assays for assessing platelet morpho...
Vollmerhaus B, Knospe C, Roos H.Phylogenetic research on the teeth of equidae beginning with dagger Hyracotherium ('Eohippus') will be summarized, subdivided into its components, analysed in a new way and finally interpreted according to several theories of evolution. In this context, specific cells (ameloblasts, odontoblasts, cementoblasts) are discussed and valued according to Preuss (1987) as active carriers of the evolution of teeth.
Nieth J, Krohn J.Aim of the study was to describe the echotexture and dimensions of the kidneys including the renal pelvis in neonatal foals using transabdominal sonography. Methods: In the course of a preliminary examination, sonographic examinations of the kidneys of 10 dead newborn foals were performed in order to determine their localization, measurement parameters, and echotexture. In subsequent necropsies, the kidneys were measured and the obtained values were compared with the sonographic measurements. A high level of agreement between the both measurement values could be demonstrated. In the main exami...
Knickelbein KE, Lassaline ME, Kim S, Thomasy SM.The iridocorneal angle (ICA) is the major pathway of aqueous humour outflow from the anterior chamber of the eye. Ultrasound biomicroscopy (UBM) has been utilised to characterise the morphology of this drainage pathway in numerous species. UBM may allow for early recognition of aqueous humour outflow obstructions in horses, allowing for earlier recognition of risk for glaucoma, a vision-threatening and painful disease. UBM morphology of the normal equine ICA has yet to be described. Objective: To determine the ultrasonographic morphology of the equine ICA by UBM in standing sedated horses. Met...
Yildiz H, Yildiz B, Arslan K, Ozgür C.In this study we present a geometric model of the ascending colon of the horse, especially the left ventral colon and the right ventral colon, the left dorsal colon and the right dorsal colon and the pelvic flexure. We also present a mathematical model of the cross sections of these ascending colon parts with the exceptions of the pelvic flexure. We show that these cross-sections correspond to the closed algebraic curves known as epitrochoid.
Mastrorilli C, Cesar F, Joiner K, Wooldridge AA, Christopherson PW.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...
Belcastro MG, Facchini F.In the medieval necropolis of Vicenne (Italy) among 130 skeletons, thirteen horsemen, recognized on the basis of the contextual burials with horse, have been found. This rite, rarely found in Europe, recalls an Asian rite, attested from the Iron Age to the Age of Migration in nomadic Asian populations. Local and Germanic goods were also found. In order to study the anthropological composition of this population, some morphometrical skeletal features have been analyzed. Heterogeneity both in the horsemen and in the other males of the necropolis has been observed. Besides the multicultural conte...
Sławomirski J, Flieger S, Jastrzebski M, Boratyński Z.The studies carried out on 2 spinal cords of horses showed that cells of the medial motor nucleus (nucleus motorius medialis) are present in all neuromers of the lumbar and sacral segment of the spinal cord. It lies in the medial part of grey matter of the ventral column, neighbouring laterally and ventrally with cells of the lateral motor nucleus, whereas dorsally with cells of the nucleus of the ventral commissural horn. Along the nucleus numerous constrictions and intervals are found, which are connected with various numbers of nerve cells in particular cross-sections.
May-Davis S, Minowa F, Brown WY.The Yonaguni pony is a rare breed of pony that has remained isolated on the westernmost island of Japan and may well retain normal morphological traits currently lost in most domestic horses (Equus caballus), such as the attachment of the nuchal ligament lamellae (NLL) from C2-C7. Recent research has found that NLL attachments are no longer present at C6 and C7 in most modern domesticated horses. This study investigated the attachments of the NLL in three Yonaguni ponies; 2 were examined in situ(deceased), and 1 was examined in vivo via ultrasound. The aim was to verify the attachments and com...
Mätz K, Gerhards H, Heider HJ, Drommer W.Bilateral blindness was diagnosed in a 5-year-old Hanoverian gelding presented for evaluation of a corneal opacity in one eye. About 12 months prior to the examination, the gelding had fallen head over, hitting his head and the cornea. Clinical and electroretinographic findings as well as pathohistologic and ultrastructural lesions of both eyes including the optic nerves are presented. Ophthalmoscopically visible pigment disruption of the non-tapetal fundus adjacent to the optic discs correlated morphologically with foci of degeneration and atrophy of the retina, whereas ophthalmoscopically vi...
Martens P.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.
Guo X, Sugita S.Four cell types including the bipolar, amacrine, horizontal and Muller cells were investigated quantitatively in the inner nuclear layer of the retina in the horse. Cells were identified on the basis of the morphology and distribution of processes leaving from their somata, cytological features and positional features. The average percentages of the above 4 cell types were 44%, 24%, 1% and 29%, respectively. The average total cell densities in the inner nuclear layer in the visual streak, the nasal and temporal regions, the dorsal and ventral regions of the retina were also estimated. It is ex...
Rodriguez MH, Chavez B, Hernandez-Avila JE, Orozco A, Arredondo-Jimenez JI.Light and scanning electron microscopy were used to compare the eggs of Anopheles vestitipennis Dyar & Knab females collected from human and animal baits in 9 villages of southern Mexico. An. vestitipennis eggs are boat-shaped, with lateral floats extending the length of the egg. Both the deck and dorsal surface are covered with hexagonal and pentagonal chorionic cells that contain round tubercles in the cell field. Crowns that enclose 3-5 lobed tubercles are present at both egg poles. By light microscopy, the mean length/width ratio of eggs of females caught at human bait were statistical...
Sławomirski J, Głuszak J.The studies performed on spinal cords of two horses revealed that cells of the nucleus of the own dorsal horn are present in all segments of lumbo-sacral part of the spinal cord. The nucleus is composed of two parts: basal and marginal. Basal part is composed of large and medium size cells situated in 2/3 of the lower part of the grey substance of the dorsal horn. The marginal part of the described nucleus is composed of elongated and spindle shaped cells situated along the dorsal margine of the grey substance of the dorsal horn. Continuity of the nucleus in lumbo-sacral part of the spinal cor...
Paryani MR, Gilanpour H.The Caspian miniature horse is one of the rare small breeds in the north of Iran. In the present study, the position of the heart and its valves were determined topographically in 4 miniature horses. We found that Caspian miniature horses have general similarities, with certain topographical variability, with other horses.
Wille KH, Nakov C.The mucous membrane of the caecum and colon ascendens of adult horses was first studied using light and transmission electron microscopy. In the surface epithelium there was an inconspicuous constellation of organelles, otherwise there was a lot of mitochondria as a source of energy for absorptive performances. Moreover, enlarged intercellular spaces exist as an indication of an increased uptake of water and electrolytes. In the basal region of Lieberkühn's crypts there were single enteroendocrine cells and numerous granules in the apical epithelial cytoplasm. The functional meaning of these ...
Denoix JM.The structural morphology of the mandibula is presented and correlated to various types of mastication in several Mammalian species. The latter include: Carnivores (Dog, Cat, Cheetah, Lion); Omnivores (Man, Chimpanzee, Hog); Herbivores (Horse, Ox, Goat, Camel, Rabbit). While the mandibula is studied as a composite unit, a more analytical, segmental approach has been included, and both are illustrated by X-rays. The aspects presented underline the distribution as well as the local modifications of compact bone, and in addition, the arrangement and the development of spongy bone trabeculae. A pr...
Lalatta Costerbosa G, Barazzoni AM, Clavenzani P, Callegari E.In this study the histochemical fiber type analysis of the articularis humeri muscle of the horse was performed. This muscle is composed of type I and type IIA fibers. A large number of spindles has been observed and the presence of these receptors could help to understand the role played by this muscle.
La CelluleJanuary 1, 1977
Volume 72, Issue 1-2 5-25
Meuleman A, Latteur B.The topography of Cochliatoxum periachtum is studied. The cuticle is very thick. The digestive, nuclear and excretory systems are located in the ectoplasm, they are not surrounded by the mesoplasm. The endoplasm is very large, it contains vegetable inclusions. By the features of its topography, this species is similar to some species belonging to the Family Ophryoscolescidae and, especially, to Eudiplodinium giganteum.
Loynachan AT, Bryant UK, Williams NM.A 35-year-old horse was submitted to the necropsy service at the University of Kentucky Livestock Disease Diagnostic Center. At necropsy, multiple 1-4-cm-diameter cystic structures were incidentally identified unilaterally in the right renal medulla and the cortex. On histologic examination, the cystic structures compressed the normal renal architecture, were lined by tall columnar epithelium that formed occasional papillary projections, and contained large amounts of mucicarmine and periodic acid-Schiff-positive mucinous material. The masses were diagnosed as renal mucus-gland cystadenomas. T...
Graves KT, Eberth JE, Bailey E.Homozygous and compound heterozygous Miniature horses for ACAN alleles D1, D2, D3* and D4 exhibit chondrodysplastic dwarfism (OMIA 001271-9796). In a previous study, the carrier rate for these four alleles, combined, was 26.2%. The purpose of this study was to investigate whether carriers of these dwarfism-causing alleles had a shorter withers height than non-carriers. A total of 245 Miniature horses were tested for these four ACAN alleles and also were measured for withers height. Of these horses, 98 were carriers and 147 were non-carriers. A statistically significant difference of 1.43 inche...
Pichardo M.Analysis of the morphological characters in North and South American horses present during Paleoindian time indicates that at least eight Equus ecospecies occurred in North America. In South America, Equus had radiated into four ecospecies, Hippidion had one, and Onohippidium had three geographically separate ecospecies. These species are found in archeological deposits ranging from ca. 13,000 to 8,000 yr B.P., in tropical habitats as well as in the high Andean and Patagonian colder ecotopes.
Payan-Carreira R, Quaresma M, Oliveira-Martins T, Silva JR.This report describes a case of blind vagina diagnosed during a pre-breeding evaluation of a 5-year-old crossbred Lusitano mare. This mare was mated twice during the previous breeding season but remained open. Clinical evaluation revealed the existence of follicles in the ovaries and an enlarged uterus. An ultrasound examination showed that a granular free-floating fluid distended the uterus. No connection was detected between the uterus and the vagina and a presumptive diagnosis of congenital vaginal obstruction was raised. On vaginal examination it was noticed that the vagina was short in de...
Samuel CA, Allen WR, Steven DH.The various cell types in the adult anterior pituitary may be distinguished at the ultrastructural level of the sizes of the secretory granules within the cytoplasm. In the fetal adenohypophysis, with the exception of prolactin-producing cells, all types may be identified after Day 100 of gestation. Morphological evidence suggests that they are producing and secreting trophic hormones. The three constituent layers of the adrenal cortex are also discernible by Day 100 of pregnancy. The cells of the zona glomerulosa have large numbers of darkly stained inclusions within the cytoplasm. The zona f...
Simoens P, Lauwers H, De Muelenare C, Muylle E, Steenhaut M.A clinical case of Horner's syndrome is described in a Standardbred horse, and the various symptoms of cranial sympathetic denervation are studied in two ponies after experimental transection of the left cervical sympathetic trunk and vagosympathetic trunk, respectively. The most prominent symptoms of equine Horner's syndrome were ptosis, local sweating and increased cutaneous temperature in the denervated area. Enophthalmos, miosis and increased lacrimation were also observed but these symptoms were mild, variable and difficult to ascertain. Prolapse of the third eyelid was not noticed. Conco...
Tschudi P, Archer RK, Gerber H.Based on morphologie studies on bone marrow, lymphnode and blood preparations the cells of equine blood and their developmental stages are described and illustrated with 32 coloured photographs.
