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.
Kumaratilake LM, Thompson RC, Eckert J.Echinococcus granulosus of equine origin from different countries possess uniform morphological characteristics. International Journal for Parasitology16: 529–540. Detailed comparative studies on isolates of larval and adult Echinococcus granulosus of equine origin from England, Scotland, Ireland, Belgium, Switzerland, South Africa and New Zealand demonstrated the morphological uniformity of the equine parasite. The morphological features of the equine strain of E. granulosus were fully characterized and it was found that on the basis of morphology alone, this strain could be differentiated ...
Andrews FM, Spurgeon TL, Reed SM.Skeletal muscle biopsy specimens were taken from 4 male horses with neuromuscular disease such as myotonia congenita, chronic myositis, exertional rhabdomyolysis, and shivers. Histologic and histochemical techniques were used to evaluate skeletal muscle morphologic features and fiber-type population, size, and area, as well as muscle enzyme activities (acid phosphatase, alkaline phosphatase, and esterase). A histochemical and histologic profile were described for each muscle biopsy specimen.
Bertram JE, Gosline JM.An engineering fracture mechanics approach was applied to the analysis of the fracture resistance of equine hoof-wall. The relationship between fracture toughness and the morphological organization of the keratin hoof tissue was investigated. Fracture toughness was evaluated using the J-integral analysis method which employs the compact tension test geometry. Tensile tests were also conducted to evaluate the effect of the morphological organization on the stress-strain behaviour. Hoof-wall has greatest fracture resistance for cracks running proximally, parallel to the tubular component of the ...
Leach D, Cymbaluk NF.Velocity-dependent changes in stride length and frequency were studied in 19 male foals, 6 to 8 months of age, and were related to body morphometrics. Eighteen distance and 8 angle measurements were digitized from 16-mm films of standing foals. The total mass and the percentage of total mass acting through the forelimbs were also recorded. Stride length and frequency data were extracted from 16-mm films of 239 strides of the walk, trot, and canter-gallop. Polynomial-regression analysis was used to determine the equation that best described the relationship between data of stride length or freq...
Krueger AS, Kinden DA, Garner HE, Sprouse RF.The morphologic and pathologic changes which occurred within the cecal mucosa of 4 horses during the onset of laminitis were determined from cecal biopsy materials obtained via a cecal fistula; the laminitis was induced with carbohydrate overload. The cecal epithelial mucosa specimens were obtained at 0 (base line), 24, 32, 48, and 72 hours after horses were given carbohydrate overload, and these were fixed and subsequently photographed. Changes in the cecal epithelium were examined by transmission electron and scanning electron microscopies. These histopathologic changes indicated that the mu...
Weiss M, Horzinek MC.In equine dermis cells infected with Berne virus particles were first detected 10 h after infection. Virions were encountered in all parts of the Golgi system and, infrequently, in the rough endoplasmic reticulum. A unique form of budding of preassembled rigid tubular nucleocapsids was demonstrated. Masses of tubular nucleocapsids of a lesser diameter and electron density were prominent in the cytoplasm and the nucleus of infected cells. Within the Golgi system and cytoplasmic cisternae virions appeared as straight or slightly curved rods. Extremely long, aberrant virions (250 nm) were occasio...
Roberts MC, Argenzio A.Amitraz, atropine, glycopyrrolate and morphine (but not its derivatives, meperidine [pethidine], oxymorphone and butorphanol) produced similar effects on clinically observed intestinal functions and significantly prolonged intestinal transit, as assessed with polyethylene glycol (PEG). However, their mechanisms of action, particularly on intestinal transport (fluid movement), may differ widely. Loperamide appeared to exert a preferential action on intestinal transport rather than motility, as there was no significant delay in PEG transit. The action of amitraz in perturbing smooth muscle coord...
Moore PF, Hacker DV, Buyukmihci NC.Angiosarcomas arising in ocular tissues of four aging horses are described. Tumors were locally invasive and eventually metastasized via the mandibular and cervical lymph nodes. Pathologically, the tumors contained well-differentiated regions, in which vascular channels were lined by pleomorphic endothelial cells, as well as poorly-differentiated regions, in which vascular channels were either rudimentary or absent. Red blood cells were scare in vascular structures formed by the tumors. Factor VIII related antigen (VIII:RAg), a blood vascular endothelial marker, was demonstrated by immunohisto...
Watson AG, Mayhew IG.Familial occipitalization of the atlas with atlantalization of the axis was defined as a single congenital disease in Arabian horses following a clinical, radiologic, and morphologic study of 16 horses with congenital malformations of the occiput, atlas, and axis, and from a study of three reported cases. The constant morphologic features were interpreted as congenital atlantooccipital fusion, hypoplasia of the atlas and dens, malformation of the axis, and modification of the atlantoaxial joint. Atlantoaxial subluxation was also a frequent finding. The clinical syndromes shown by these horses ...
Rantanen NW.Ultrasound examination offers important diagnostic and prognostic information in renal disease of the horse. Differentiation between acute nephrosis and chronic renal disease can usually be made because of the advanced degree of morphologic change usually prevalent in chronic conditions. Dilatations of the recesses and pelvis (hydronephrosis) as well as the relative thickness of the renal cortex and medulla are readily determined. Mineral densities (calculi) are recognizable by their characteristic acoustic shadowing.
Genovese RL, Rantanen NW, Hauser ML, Simpson BS.In our 3 years of clinical experience, we have found that diagnostic ultrasound provides the veterinarian with a valuable diagnostic tool. It allows the clinician to quantify morphologic change that has occurred as a result of soft-tissue injuries, even when the clinical findings are ambiguous or insufficient. In cases in which aggressive postinjury therapy has been instituted prior to presentation, diagnostic ultrasound is often the only noninvasive method that can ascertain the extent of the horse's injury. Diagnostic ultrasound provides the technology to detect injuries before they become p...
Johnson R.A review of the literature on intestinal atresia of domestic animal species and humans was done. The 5 types of intestinal occlusions described in human infants are atresia type 1, atresia type 2, atresia type 3, stenosis, and the "apple peel" or "Christmas tree" deformity. The intestinal defects described in domestic animal species such as the bovine, equine and porcine are similar to those of human infants. The "T-formation", an intestinal defect of the bovine resembling atresia type 3, and rectal stricture, an acquired intestinal defect of the porcine resembling stenosis, were described rec...
Meschter CL, Tyler DE, White NA, Moore J.Thirty horses were admitted to the University of Georgia Veterinary Medical Teaching Hospital with colic severe enough to warrant surgery and/or euthanasia. Gastrointestinal tracts of these 30 horses were histologically examined for morphologic changes. The horses were grouped according to cause of the colic (ie, simple obstruction, strangulation obstruction, thromboemboli, and inflammation). Lesions were graded as to severity, and grade scores were correlated with survival or nonsurvival. Mucosal changes developed distal and proximal to the primary lesion site and, although there were some di...
Reinemeyer CR, Herd RP.Haustral portions of intestine of 6 horses were isolated by excising the taeniae coli from the cecum and the ventral colon. Uniform 5-cm X 5-cm sections were cut from the haustra and were illuminated from the serosal side with a strong light source (mural transillumination). Cyathostome larvae encysted in the mucosa and submucosa were observed at 15 X magnification and counted. Two separate counts of the larvae in 80 replicates of tissue by the mural transillumination technique (MTT) revealed no significant (P less than 0.05) difference between sample means. Larvae in tissue sections were coun...
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...
Katila T, Lock TF, Ely RW, Smith AR.The study was designed to determine differences between normal mares and mares with endometrial pathology in the inflammatory response after bacterial challenge. Six normal mares (biopsy category I) and 4 mares with pathological endometrial changes (biopsy category II) were given an intrauterine infusion of β-hemolytic streptococci on the second day of estrus. All mares had a similar kind of inflammatory response after the bacterial inoculation as assessed by rectal and vaginal examinations. There were no significant differences in the amount of discharge, uterine tone, uterine size and cervi...
Chamorro CA, de Paz P, Sandoval J, Fernandez JG.The morphological characteristics of bovine and equine gustatory lingual papillae are compared by scanning electron microscopy. The fungiform papillae in the cow have a shape that corresponds to their name, while in the horse, they almost do not emerge from the surface of the tongue. These papillae show taste pores in both species. The vallate papillae, four times larger in the horse than in the cow, show a complex organization of papillae and secondary grooves in the horse. In the cow, they occur single and are surrounded by a thick annular pad of lingual mucosa. Taste pores have been observe...
Maczulak AE, Dawson KA, Baker JP.A total of 114 bacterial isolates were obtained from the cecal contents of two mature cecally fistulated horses on a habitat-simulating medium containing 40% energy-depleted cecal fluid. Of these isolates, 108 were maintained in pure cultures and were tentatively grouped on the basis of cell morphology and physiological characteristics. Gram-negative rods (50.9%), gram-positive rods (22.8%), and gram-positive cocci (21.9%) represented the largest groups isolated from these animals. Fifty isolates were tested for their ability to grow in media containing urea, ammonia, peptones, or amino acids ...
Yovich JV, Powers BE, Stashak TS.The intervertebral disks and adjacent vertebral bodies of the 2nd to 7th cervical vertebrae from 17 horses (3 months to 19 years of age) were examined grossly and by light microscopy. In each specimen, the disk tissue was fibrocartilagenous centrally and became more fibrous peripherally, but without a distinct demarcation between the nucleus pulposus and anulus fibrosus. Demarcation between the anulus fibrosus and the dorsal longitudinal ligament was not apparent. With increasing age of the horses, cellularity of the central fibrocartilagenous portion of the disk decreased. The caudal end plat...
Riemersma DJ, Schamhardt HC.The mechanical properties of the deep digital flexor tendon (DDFT), the superficial digital flexor tendon (SDFT) and the suspensory ligament (SL) of the hindlimb of the horse were studied in vitro. The tendons were observed at several morphologically distinct sites. The loaded tendon is homogeneously strained, in spite of large variations in cross-sectional area. Consequently the modulus of elasticity was inversely proportional to the corresponding cross-sectional area and ranged from 738 MPa (megaPascal, N mm-2) to 1398 MPa within the DDFT, from 1000 MPa to 1282 MPa within the SDFT and from 5...
Watkins JP, Auer JA, Gay S, Morgan SJ.Full-thickness defects were surgically created in the superficial digital flexor tendons of the front limbs of 20 horses. Tissues formed within the defect were evaluated histologically, and the collagen composition of the tissue was determined by immunofluorescence. Transformation occurred from loose fibrillar areas of types I and III collagen and pericellular types IV and V collagen to dense bundles of type I collagen fibers. Loose fibrillar areas of types I and III collagen were present after 24 weeks. Histologically, in horses killed after 2 weeks, the tissue within the defect was a randoml...
Hayes KE, Pierson RA, Scraba ST, Ginther OJ.The morphological changes in ultrasound images of the uterus at various times of the year were characterized in nonbred mares, using a linear-array scanner. The uterus was recorded as having an ultrasonic morphology characteristic of diestrus (uterine score 1, endometrial folds not visible), estrus (score 3, distinct endometrial folds), or an intermediate stage (score 2). In Experiment I, uterine scores for the first ovulatory period of the year were compared to scores for the second period in 23 pony mares. More mares (P<0.05) showed endometrial folding prior to the second ovulation of the...
Tablin F, Weiss L.The equine bone marrow responds to blood loss by increased erythropoiesis, only releasing reticulocytes into the peripheral circulation in severe chronic anemia. We have used morphometric analysis based on electron microscopy of the equine marrow to examine the maturation and release of reticulocytes. Developing red cells in the bone marrows of normal and chronically anemic horses were divided into four stages: early, intermediate, late-stage erythroblasts, and reticulocytes. Morphometric analysis of each stage included volume density of mitochondria per micron3 of cytoplasm, surface area of t...
Farrar RG, Klei TR.Strongylus edentatus was successfully cultured in vitro to the fourth larval stage (L4). Some growth continued for periods of 40-50 days at which time reductions in viability were observed in some of the culture systems tested. Various combinations of media, sera, buffers and organ explant cultures were tested. All cultures were incubated at 37 C in an atmosphere of 95% air and 5% CO2. Larvae underwent growth and differentiation to the L4 in all medium-serum combinations with and without organ explant cultures. Development and growth did occur but viability was reduced to insignificant levels ...
Bertone AL, Park RD, Turner AS.Radiographs of 23 foals (35 forelimbs) with carpal region angular limb deformities, which later were corrected by hemicircumferential transection of the periosteum and periosteal stripping, were evaluated as to geometric and morphologic abnormalities. Geometric evaluation included deviation angle and deviation pivot point. Morphologic abnormalities were categorized as: asymmetric width of the distal radial physis; asymmetric width of the distal radial epiphysis; carpal bone collapse or fracture; carpal bone hypoplasia; carpal bone displacement; and metacarpal bone displacement. Fifty-seven per...
Davies ME, Bingham RW.Two morphological types of spirochaete were found in the horse caecum measuring 4 to 6 micron by 0.3 to 0.4 micron and 6 to 8 micron by 0.1 to 0.2 micron. Attempts were made to culture the organisms but none survived subculture beyond the primary isolate. Electron microscopy revealed that many of the organisms were infected by bacteriophages.
Ginther OJ, Bergfelt DR, Leith GS, Scraba ST.Pregnancy was determined by ultrasound on Days 11, 15, 20, 25, 30, 35, 40, 45, and 50 in 154 ponies and 27 horses. In ponies, the embryonic loss rate for Days 11 to 15 (28 154 , 18.2%) was greater (P<0.01) than for any of the subsequent five-day intervals (0% to 3.3%). There were no losses during Days 11 to 15 in horses (0 27 ), and the difference between ponies and horses was significant. The loss rates for the seven periods encompassing Days 15 to 50 were not significantly different among periods. Pseudopregnancy occurred more frequently (P<0.01) following embryonic loss after Day 20 (...
Selim SA, Soliman R, Osman K, Padhye AA, Ajello L.Isolation of Histoplasma farciminosum from five horses, showing typical signs of histoplasmosis farciminosi (epizootic lymphangitis) was successfully attempted. The mycelial form of H. farciminosum was isolated on Sabouraud dextrose agar enriched with 2.5% glycerol, brain heart infusion (BHI) agar enriched with 10% horse blood and PPLO dextrose glycerol agar. The last medium proved to be the most effective, both for primary isolation and subculturing of the fungus. It was found that on primary isolation, the lag phase of the mycelial form of the fungus was relatively long, involving 4-8 weeks ...
Morgan J, Curtis Shaw G, Weisman J, Cecere T, Carvallo-Chaigneau FR.A 2-d-old Warmblood colt was submitted for autopsy with a spectrum of bilateral ocular abnormalities. At postmortem examination, a constellation of lesions within the anterior segment included retention of ectodermal elements, compatible with choristoma. Ocular choristomas can be localized to different intraocular structures and are rare in equids. The morphologic features in our case were suggestive of abnormal corneal differentiation.
Nieman RT, Lamim LI, Del Fava C.Fetal loss in mares can result from a range of causes, including infectious agents or noninfectious conditions such as neoplasia, which may originate from either the fetus or the dam. Among neoplastic conditions, teratomas are rarely reported and, to date, have not been described in the equine fetal testis. Teratomas arise from the partial differentiation of pluripotent germ cells and may occur in young and adult horses, typically in cryptorchid testes. Their gross and histopathological features vary widely between cases. This report describes a rare case of bilateral fetal testicular teratoma...
Oliveira LLV, Caldas MCAR, Marval LME, Marval CA, Carvalho JGS, Matos JJRT, Malacarne BD, Paz CFR.A 2-year-old mixed-breed mare was examined at the property due to swelling and fistula on the right mandible. Oral examination and radiographs revealed the presence of an apical abscess involving the 410 tooth. The tooth was extracted entirely and confirmed radiographically. One year later, the owner reported a reoccurrence of clinical signs. A new radiographic evaluation revealed a radiopaque area in the alveolar socket of the 410 tooth filled with spongy-looking bone. An extraoral approach to the alveolar socket was performed, and the content removed had the appearance of a dental element.
Selecky ME, Louie EW, Donnelly C, Finno CJ, Morgan JM.Echocardiographic reference intervals for Quarter Horses are infrequently reported. Objective: To provide standard echocardiographic measurements for sedentary Quarter Horses and evaluate the relationship between physical characteristics (body weight, age, sex) and echocardiographic measurements. Methods: Forty-one sedentary Quarter Horses, free of cardiac disease, from a university research herd. Methods: A cross-sectional study evaluating standardized echocardiograms performed on sedentary Quarter Horses (41) between 2020 and 2022. Reference intervals were calculated for raw and weight-corre...
Gürelli G, Göçmen B.The aim of this study was to determine the cytological features of 2 endocommensal ciliates, P. colpoidea and P. minuta belonging to genus Paraisotricha found in the hindgut of 15 Turk rahvan and 15 English and Arabic horses from Izmir, compare the morphological characters of species with their original descriptions and previous reports and discuss the similarities and differences. Methods: The cytological features of two endocommensal ciliates were investigated with the pyridinated silver carbonate impregnation and silver nitrate impregnation techniques at the level of light microscopy. Resul...
Harland MM, Fedele C, Berens v Rautenfeld D.Horses are highly susceptible to lymphedema. Knowledge of the morphological components of lymphatic collectors is therefore essential to understanding the function of the lymphatic system. A better knowledge of the lymphatic system allows the development of more effective treatments against lymphedema. The composition of hypodermal and deep lymphatic collectors was investigated with immunohistochemical staining, using antibodies against proteins of the collector walls from the skin in the hind limbs of 10 healthy horses. Lymphatic collectors can be subdivided into passive (elastic fibers) and ...
Rannamäe E, Andrianov V, Järv E, Semjonov A, Haak A, Kreem J.The remains of a horse's hind foot - a third metatarsal bone and three phalanges - were found in a presumed waste pit of a prosperous medieval household in Viljandi, Estonia, dated from the second half of the 13th to the beginning of the 15th century. The metatarsal bone had been broken during the horse's lifetime and showed evidence of partial healing. Using archaeological, zooarchaeological, morphological, microscopic, densitometric and radiographic analyses, we investigated the bones and the healing process in order to understand animal treatment in a medieval urban context. Our results sho...
Asperio RM, Marzola P, Sbarbati A, Osculati F, Addis F.To analyze the tendon of the deep digital flexor (TDDF) muscle of the forelimb in horses by use of a contrast radiographic agent (gadopentate dimeglumine [Gd-DTPA/Dimeg]) and magnetic resonance imaging (MRI) and to determine the concentration of water protons in the tendons by use of MRI. Methods: 8 TDDF harvested from the forelimbs of 6 horse cadavers. Methods: Examinations were performed on the same portion of each tendon. Tendons were examined by use of two techniques: MRI before and after treatment with Gd-DTPA/Dimeg as well as scanning electron microscopy. Results: Tendons did not have de...
de Oliveira AC, Rosenbruch M, Schulz LC.The morphology of asteroid bodies in equine arteries is demonstrated by light microscopy as well as by scanning and transmission electron microscopy combined with chemical analysis. Asteroid bodies first occur in horses at four weeks of age in all investigated tissues except the esophagus and always are located in the subendothelial space. The number, shape, ultrastructure and chemical composition of asteroid bodies differ markedly--depending on the age of the horse. Asteroid bodies are round and smooth in foals, but are shaped irregularly and have several projections and marked stratified cal...
Herdan CL, Nicholson CL, Firth EC.The third carpal bone (C3) responds to exercise by adaptive modeling of bone and articular calcified cartilage along the dorsal load path. Canals penetrating articular calcified cartilage, thought to contain vascular tissue, are reported in numerous species. Their significance remains unclear. Our objective was to determine if the number of canals was significantly different in strenuously exercised and control young horses and in a site of intermittent high loading compared to sites sustaining lower habitual loads. Volumetric bone mineral density in the radial facet of C3 of strenuously exerc...
MacLaren JA.Locomotion in terrestrial tetrapods is reliant on interactions between distal limb bones (e.g. metapodials and phalanges). The metapodial-phalangeal joint in horse (Equidae) limbs is highly specialized, facilitating vital functions (shock absorption; elastic recoil). While joint shape has changed throughout horse evolution, potential drivers of these modifications have not been quantitatively assessed. Here, I examine the morphology of the forelimb metacarpophalangeal (MCP) joint of horses and their extinct kin (palaeotheres) using geometric morphometrics and disparity analyses, within a phylo...
Wilsher S, Bowker A, Silva J, Allen WRT.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...
Solar Diaz IDP, Strauss Borges Junqueira G, Aparecida Rocha Cruz V, Albano Araújo de Oliveira C, Nunes de Oliveira H, Miguel Ferreira de Camargo G....Principal component analysis (PCA) was applied to evaluate the genetic variability and relationship between 15 morphometric traits in 91,483 Campolina horses, as well as to propose an index based on an aggregate genotype that promotes a particular selection objective. PCA was applied to the genetic (co)variance matrix among variables. After calculation of the principal components, the breeding values were estimated to obtain an index related to the component that explained most of the variation. The first principal component (PC1) accounted for 97.8% of the total additive genetic variance of t...
Murabayashi H, Hondo E, Kitamura N, Furuoka H, Taguchi K, Nambo Y, Yamada J.One of the most attractive characteristics of a horse testis is the change of the weight during development. As the testicular weight changes and the number of Leydig cells decreases, pigments appear in interstitial tissues. In the present study, the characteristics of the pigments found in the interstitial tissues were examined histochemically and ultrastructurally. Specific stainings indicated that the pigmented granules showed almost all of the histological and histochemical characteristics of ceroid or ceroid-like pigment. The cells showed positive reaction for acid phosphatase while the p...
Kharchenko VA, Lichtenfels JR, Pilitt PA, Krecek RC.As part of a revision of the systematics of the Cyathostominea of equids, we determined that the single type-specimen of Cylicocyclus adersi Boulenger, 1920 is missing and a modern description of this rare species parasitic in donkeys Equus asinus L. and zebras E. burchelli (Gray) and E. zebra L. is not available. Systematists at a workshop on the systematics of the Cyathostominea of horses, convened on August 11, 1997 in Sun City, South Africa, listed C. adersi as a species inquirenda . Herein, we provide a redescription of C. adersi and propose a neotype for the species. The distinctive shap...
Pasquel SG, Agnew D, Nelson N, Kruger JM, Sonea I, Schott HC.Although the equine renal pelvis and terminal recesses have been described post mortem, little information exists about the endoscopic appearance of these structures in the living horse for guiding ureteropyeloscopy. Objective: To further document the anatomy of the upper urinary collecting system, specifically the renal pelvis and terminal recesses, of the horse. Methods: Descriptive study of cadaver material. Methods: Kidneys were harvested from 10 horses. Magnetic resonance imaging was performed after distension of the renal pelvis with an elastomer casting material, followed by visual insp...
Gable TL, Woods GL.The objectives were to compare cumulus type with nucleus form in equine cumulus oocyte complexes (COCs), to define the percentage of germinal vesicle (GV)-stage oocytes within a population of mares, and to further define GV nucleus shapes of equine oocytes. Cumulus types were as follows: 1) compact (56/208, 26.9%), 2) slightly expanded (37/208, 17.8%), 3) moderately expanded (27/208, 13.0%), 4) greatly expanded (15/208, 7.2%), or 5) denuded (73/208, 35.1%). One hundred thirty of 208 COCs (62.5%) were GV-stage, 21/208 (10.1%) were condensed chromatin-stage, 8/208 (3.8%) were polar body-stage, 4...
Flieger S, Sławomirski J, Boratyński Z, Jastrzebski M.Two medullae oblongatae of horses were cut into 15 microns cross-sections and stained according to the modified method of Nissel. The lateral motor nucleus lies in the lateral and median part of the ventral column of spinal cord grey matter. It adjoins medially nucleus motorius medialis of the spinal ventral column. Cells of this nucleus occur both along the whole lumbar and sacral segment of the spinal cord. In the lateral motor nucleus three cell groups are distinguished-median, basal and lateral. The latter is divided in some segments into subgroups-dorsal and ventral. Along the nucleus qui...
Huhtinen M, Lagneaux D, Koskinen E, Palmer E.Seventy-five embryos were collected 6 days after ovulation. Sixty embryos were frozen in straws using glycerol as the cryoprotectant in an automatic freezer. In Experiment 1 the freezing and thawing media were supplemented with 1.3 g/l PVP; in Experiment 2 the supplement was 5% FCS. The embryos were thawed for 30 s at +37 degrees C in a waterbath. In Experiment 1 glycerol was removed from 10 embryos in 6 steps. In 10 other embryos, glycerol and sucrose were both removed from the medium in 6 steps. After glycerol and sucrose removal, the embryos were stained with 4',6'-diamidino-2-phenylindole ...
Salamanca-Carreño A, Parés-Casanova PM, Monroy-Ochoa NI, Vélez-Terranova M.This study examined paedomorphosis in PAH and F1 crossbreds. A sample of 99 horses was selected from 40 different breeders and consisted of three groups: stallions ( = 16), mares ( = 53), and geldings ( = 30), ranging from 10 months to 27 years in age. All horses presented a concave celloid lateral left head profile in the acquired photographic images. The hypothesis proposed in this study suggested the lateral profile of the head in juveniles was representational in the adult form due to the neonate's facial bones (part of the splanchnocranium) developing at a different rate to those of the s...
Le Goff D, Nouvelot A, Fresnel J, Silberzahn P.1. Plasma lipoproteins from six thoroughbred horses were separated by density gradient ultracentrifugation. For each sample, lipoprotein bands were visualized by means of a prestained plasma control and characterized by electrophoretic, chemical and morphological analysis. 2. Very low density lipoproteins (VLDL) were isolated at d less than 1.018 g/ml. 3. Two clearly resolved bands were detected in the low density lipoprotein fraction (LDL). The density limits were evaluated as follows: LDL1(1.028 less than d less than 1.045 g/ml) and LDL2(1.045 less than d less than 1.070 g/ml). Marked differ...
Lakritz J, Wisner ER, Finucane T, O'Brien TR, Tyler WS, Pascoe JR, Plopper CG.Interstitial and bronchointerstitial pulmonary patterns are commonly observed in thoracic radiographs of Thoroughbreds. Prominent interstitial and bronchointerstitial pulmonary patterns are observed in clinically normal horses, and in horses with respiratory tract disease. Until recently, the relevance of these pulmonary patterns was not known. Previous studies indicated that bronchiolitis, bronchiolar epithelial hyperplasia, epithelial metaplasia, and bronchial arteriolar recruitment correlated strongly with the prominence of the interstitial and bronchointerstitial pulmonary patterns observe...
Salamanca-Carreño A, Parés-Casanova PM, Crosby-Granados RA, Vélez-Terranova M, Bentez-Molano J.The skull is divided into neurocranium and splanchnocranium, and its variation allows ecomorphological studies to learn about possible evolutionary and adaptive characteristics. The basicranial organization of the neurocranium and splanchnocranium modules was studied in a sample of 31 skulls from adult Araucanian horses by means of 2D geometric morphometric techniques. The neurocranium and splanchnocranium modules on the ventral aspect were analyzed separately using a set of 31 landmarks. The RV coefficient (the multivariate analog of a correlation) was estimated to analyze the independence of...
Larsdotter S, Holm L, Dahlborn K, Jansson A, Josefsson M, Ridderstråle Y.Sweat gland morphology and carbonic anhydrase (CA) distribution was studied after exercise in trained and untrained horses using a histochemical technique and light microscopic image analysis. Three trained and 3 untrained Standardbred trotters performed an exercise test (20 min trot at 6 m/s with 5 min walk at 1.8 m/s in the beginning and end) on a high-speed treadmill at 35 degrees C. Skin biopsies were taken before exercise and after trot. The fluid loss after exercise was 10, 12 and 12 g/kg bwt in the untrained horses and 4, 6 and 11 g/kg in the trained. Trained horses had a larger cell ar...
Hinchcliff KW, McGuirk SM, MacWilliams PS, Cooley AJ.Changes in renal function, determined by pharmacokinetics of phenolsulfonphthalein (PSP), and renal morphologic features were examined in adult pony mares given 20 mg of gentamicin sulfate/kg of body weight, IV, q 8 h (group A) n = 7 or isotonic saline solution, IV, q 8 h, n = 5 (group B) for 14 days. Susceptibility of ponies to gentamicin-induced nephrotoxicosis was varied. Two group-A ponies developed acute renal failure and were euthanatized before treatment day 14, whereas 5 group-A A ponies did not develop physical or behavioral abnormalities after 14 days of gentamicin administration. Al...
Bolat D, Yıldız D, Bahar S, Yürüker S, Kaymaz F, Ilgın C, Bozkurt EÜ, Karahan S, Sabancı SS.We investigated the microscopic structure of transverse sections of the oculomotor, trochlear and abducens nerves of Arabian foals using stereological methods. Bilateral nerve pairs from 2-month-old female Arabian foals were analyzed. The tissues were embedded in plastic blocks, then 1 µm thick sections were cut and stained with osmium tetroxide and methylene blue-azure II. Stereology was performed using light microscopy. Morphometry showed that the right and left pairs of nerves were similar. The transverse sectional areas of the oculomotor, trochlear and abducens nerves were 1.93 ± 0.19 mm...
Gebhart W, Niebauer GW.The morphological substrates of pigmented and depigmented skin as well as the structural characteristics of spontaneously developing melanomas were revealed by clinical, light- and electron microscopic methods in gray horses (Lipizzaner breed) from the Vienna Spanish Riding School. On clinical investigations in a group of 31 older horses (more than 10 years old) 20 exhibited melanomas, whereas 23 younger animals (less than 10 years of age) had no evidence for visuable melanotic tumors. Concomitantly with the progressive graying of the hair a depigmentation of the skin was frequently observed. ...
Kutara K, Ono T, Hisaeda K, Inoue Y, Henmi C, Sho K, Ohnishi A, Ohzawa E, Une Y, Iwata E, Shibano K, Asanuma T, Kitagawa H.Noma horses have the smallest body size among native Japanese horses and are classified as pony breeds by their size. Additionally, the Japanese horse breeds are classified into a single lineage, which includes Mongolian horses. Great intraspecific differences reportedly exist in the head shapes of domesticated horses, which have been investigated in various horse breeds. The present study aimed to evaluate the size of the nasal conchal bullae, and the paranasal sinuses of Noma horses in relation to the skull dimensions using computed tomography. Reconstructed images of the heads of five adult...
Vogelsang MM, Kraemer DC, Potter GD, Stott GG.Oocytes recovered by follicular aspiration were evaluated by light and transmission electron microscopy. Of the 22 oocytes, 4 exhibited characteristics of degeneration, and the remaining 18 were in various stages of meiotic development. Of the non-degenerate oocytes, 14 were in the germinal vesicle stage, 2 had undergone nuclear membrane disintegration, 1 displayed chromosomes in late metaphase I-early anaphase I, and 1 oocyte was in the process of extrusion of the first polar body. Although some oocytes retained complete cumulus cell investments, oocytes were predominantly enclosed only by th...
