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.
Simoens P, Van den Broeck W, Lauwers H.Vascular corrosion casts of 12 equine, 15 bovine and 50 porcine eyes were studied scanning electron microscopically for the presence of posterior ciliary veins. These veins drain a postequatorial segment of the choroid and emerge near the posterior bulbar pole. They complement the four vorticose veins that emerge near or at the equatorial zone of the eyeball and the slender choroidoretinal veins that drain the peridiscal area of the choroid. Posterior ciliary veins were observed in all equine and bovine eyes examined. In these species they presented a large variation in size, number and positi...
Cheadle MA, Dame JB, Greiner EC.The Virginia opossum (Didelphis virginiana) is a definitive host for multiple Sarcocystis species including Sarcocystis neurona, one of the causative agents of equine protozoal myeloencephalitis (EPM), a severe, neuromuscular disease of horses. Size and morphologic characteristics of isolates of Sarcocystis shed by the opossum were examined to determine if differences were useful in discriminating between the isolates and/or species. Collections of sporocysts from 17 opossums were molecularly characterized and measured using an ocular micrometer. The mean sporocyst size of isolates of S. neuro...
van Hoogmoed L, Snyder JR, Pascoe JR, Olander HJ.This report describes the evaluation of uniformity of morphological injury of the large colon following severe colonic torsion in 17 horses presented to the Veterinary Medical Teaching Hospital. In 16 horses, twist occurred at the colonic base and in 1 at the sternal and diaphragmatic flexure. Eleven of the 17 horses were subjected to euthanasia at surgery and 6 of 17 following surgical correction within 4 days postoperatively. The objective of this study was to determine if the degree of histological changes present at the pelvic flexure were uniformly distributed throughout the regions of th...
Malmgren L, Andresen O, Dalin AM.The aim of this study was to investigate the effect of gonadotrophin-releasing hormone (GnRH) immunisation on mature stallions that had been used for breeding. Four Standardbred stallions were used in the study: 3 experimental animals and 1 control animal. Semen was collected regularly, i.e. twice/week, during the 4 months prior to the experimental period. The stallions were immunised against GnRH with a GnRH-BSA conjugate. Equimune was used as the adjuvant. The stallions were immunised on 5 occasions, 4 at 2 week intervals, and the fifth 4 weeks after the fourth. Blood samples were taken once...
Fukuda T, Kikuchi M, Kurotaki T, Oyamada T, Yoshikawa H, Yoshikawa T.Atrophy of seminiferous tubules and interstitial fibrosis are frequently observed in aged horses. Samples from 8 male Thoroughbreds, age 4-24 years, were subjected to histological, electron microscopical and immunohistochemical examination and statistical analysis. There were statistically significant increases in collagen fibres in the lamina propria of seminiferous tubules and testicular interstitium in 3 horses age 23 and 24 years compared with 5 horses age 4-20 years (P<0.001). Lamina propria surrounding atrophic tubules was thickened by an increase in collagen type IV and elastic fibre...
Muylle S, Simoens P, Lauwers H.The distribution of intratubular (peritubular) dentine was studied by scanning electron microscopy in 12 equine incisor teeth. High levels of intratubular dentine were found in the peripheral regions of the dentine. In these areas, a marked asymmetry occurred, as intratubular dentine was predominantly deposited onto the side of the dentinal tubular walls nearest to the dentino-enamel junction. The quantity and asymmetry of intratubular dentine were reduced towards the centre of the tooth. The significance of these variations in the amount and distribution of intratubular dentine between the di...
Van Hoogmoed LM, Snyder JR, Nieto JG, Harmon FA, Timmerman BL.To determine effect of leukocyte depletion on hematologic, morphologic, and metabolic variables of equine jejunum after induction of arterial low-flow ischemia and reperfusion by use of an extracorporeal circuit. Methods: 14 healthy adult horses. Methods: A segment of jejunum was surgically removed and maintained in an isolated circuit for 3 hours (control group), arterial flow was reduced to 20% of baseline for 40 minutes followed by 1 hour of reperfusion (low-flow group), or leukocyte depletion was filter-induced, and low-flow ischemia and reperfusion were conducted as in the low-flow contro...
Blottner S, Warnke C, Tuchscherer A, Heinen V, Torner H.The study compared quality and freezability of stallion semen during breeding and non-breeding seasons. Ejaculates were collected twice per week from four stallions during May (n = 24) and December (n = 24). The semen was mixed with skim milk extender, centrifuged and resuspended in fresh extender. Aliquots of this sperm suspension were separated from extender and diluted in TALP medium for sperm evaluation or with cryoextender (type "Gent" or a combination of Triladyl and skim milk). Samples of 0.5ml were cryopreserved in straws using a programmed freezer. Parameters of sperm quality were eva...
Guo X, Sugita S.Topography of ganglion cells in the retina of the horse (Thoroughbred) was analyzed in the wholemount retina stained with cresyl violet, and a total number of ganglion cells were estimated. Sizes of ganglion cells were also measured and size spectra were analysed. The main results showed that: (1) a common point in 4 wholemount retinae, based on cell densities and retinal locations, was that a retina could be divided into 5 regions, namely visual streak, nasal, temporal, dorsal and ventral region to the visual streak. A maximum cell density of 4,000 cells/mm2 was found in the visual streak. An...
Erickson JD, Lee DV, Bertram JE.The goal of this study was to identify changes in acetabular morphology associated with the use of horses by Native Americans. Previous studies reported "elongate" acetabula in horseback-riding members of the Omaha and Ponca populations. Such a difference in acetabular shape is a potentially useful osteological marker of habitual horseback riding. This report compares acetabula of adult males from two Native American Arikara populations known to have differed substantially in their use of horses. Population samples were from separate sites in South Dakota: Larson (nonriding) and Leavenworth (r...
Van Hoogmoed L, Snyder JR, Pascoe JR, Olander H.To determine if morphologic evaluation of intraoperative biopsies of the large colon could be used to accurately predict outcome in horses with large colon torsion. Methods: Clinical study. Methods: Fifty-four horses with large colon torsion. Methods: A full-thickness biopsy was collected from the pelvic flexure of the ascending colon after correction of naturally occurring colonic torsion. Morphologic changes were evaluated and graded for interstitial tissue to crypt ratio (I:C ratio), percentage loss of superficial and glandular epithelium, and the degree of hemorrhage and edema. These varia...
Carnevale EM, Ramirez RJ, Squires EL, Alvarenga MA, Vanderwall DK, McCue PM.In the present study, 638 embryo transfers conducted over 3 yr were retrospectively examined to determine which factors (recipient, embryo and transfer) significantly influenced pregnancy and embryo loss rates and to determine how rates could be improved. On Day 7 or 8 after ovulation, embryos (fresh or cooled/transported) were transferred by surgical or nonsurgical techniques into recipients ovulating from 5 to 9 d before transfer. At 12 and 50 d of gestation (Day 0 = day of ovulation), pregnancy rates were 65.7% (419 of 638) and 55.5% (354 of 638). Pregnancy rates on Day 50 were significantl...
Muylle S, Simoens P, Lauwers H.This paper gives an anatomical overview of the dentinal structure in equine incisor teeth with special reference to the three-dimensional organization, the number and the diameter of the dentinal tubules. The spatial arrangement of equine dentine was examined by scanning electron microscopy of occlusal surfaces and longitudinally fractured teeth and by light microscopy of both decalcified and ground sections. The dentinal tubules of the peripherally situated primary dentine were directly continuous with those of the circumpulpal secondary dentine. The tubules had numerous side branches along t...
Muylle S, Simoens P, Lauwers H.The dentinal tubules of 20 permanent equine incisors were investigated by scanning electron microscopy. Occlusal surfaces and longitudinal fracture planes of both etched and undecalcified teeth were examined. Three different types of structure were observed inside the dentinal tubular lumen. Odontoblastic processes could only be visualized in the circumpulpal parts of the tubules. The more peripheral parts were empty or housed cylindrical structures that probably correspond to the laminae limitantes. Collagen fibres were frequently observed in the tubular lumina and were most numerous in the c...
Beech DJ, Roche ED, Sibbons PD, Rossdale PD, Ousey JC.Mean glomerular volume has previously been estimated, using stereological techniques, specifically the point-sampled intercept (PSI), either from isotropic or from vertical sections. As glomeruli are approximately spherical structures, the same stereological technique was carried out on vertical and arbitrary sections to determine whether section orientation had any effect on mean glomerular volume estimation. Equine kidneys from 10 individuals were analysed using the PSI method of estimating volume-weighted mean glomerular volume (MGV); for each kidney, arbitrary and vertical sections were an...
Manglai D, Wada R, Kurohmaru M, Yoshihara T, Kuwano A, Oikawa M, Hayashi Y.The present study attempted to clarify the characteristics of the guttural pouch mucosa in equines and to evaluate its foreign substance clearance ability. The specimens were collected from nine regions (eight in the guttural pouch mucosa, and one in the nasopharynx mucosa). We first examined the pouch mucosa by light and electron microscopy. We then measured the frequency of goblet cells per 200 epithelial cells, the length of the cilia, the thickness of the epithelial cell layer and lamina propria and statistically analyzed the data. The guttural pouch mucosa consisted of stratified columnar...
Mills ML, Rush BR, St Jean G, Gaughan EM, Mosier D, Gibson E, Freeman L.To determine the serum and synovial fluid concentrations of ceftiofur sodium after intraarticular (IA) and intravenous (IV) administration and to evaluate the morphologic changes after intraarticular ceftiofur sodium administration. Methods: Strip plot design for the ceftiofur sodium serum and synovial fluid concentrations and a split plot design for the cytologic and histopathologic evaluation. Methods: Six healthy adult horses without lameness. Methods: Stage 1: Ceftiofur sodium (2.2 mg/kg) was administered IV. Stage 2: 150 mg (3 mL) of ceftiofur sodium (pHavg 6.57) was administered IA into ...
Worster AA, Nixon AJ, Brower-Toland BD, Williams J.To determine the morphologic and phenotypic effects of transforming growth factor beta1 (TGFbeta1) on cultured equine mesenchymal stem cells (MSC) and articular chondrocytes. Methods: Bone marrow aspirates and articular cartilage samples from a 2-year-old and two 8-month-old horses. Methods: After initial isolation and culture, MSC and chondrocytes were cultured in Ham's F-12 medium supplemented with TGF-beta1 at a concentration of 0, 1, 5, or 10 ng/ml. Medium was exchanged on day 2, and cells were harvested on day 4. Medium was assayed for proteoglycan (PG) content. Total RNA was isolated fro...
Lopes MA, Pfeiffer CJ.The hindgut is the major site in the horse for nutrient digestion and absorption. Most of this activity occurs in the large intestinal compartments, i.e., cecum, right and left ventral colon and left and right dorsal colon. The colonic pelvic flexure is a short and narrow loop connecting the left ventral and left dorsal colon. It is not significant directly in digestive and absorptive processes but plays an important functional role in regulating colonic aboral and retropropulsive transit of digesta through its motility pacemaker activity. The pelvic flexure also contributes to the pathophysio...
Macdonald AA, Chavatte P, Fowden AL.Scanning electron microscopy was used to examine the microstructure of the maternal and fetal placenta from 25 pregnant ponies (Equus caballus) throughout the second half of gestation. Samples of placenta, 2-6 cm(2)in area, were collected from the antimesometrial region of the pregnant horn at 105 days (n=1), 165-219 days (n=5), 260 days (n=3), 270-277 days (n=3), 313-337 days (n=11) and immediately after spontaneous delivery at term (n=2). The maternal microcaruncle appears to be created from a clustering of about 16 uterine crypts encapsulated in a connective tissue sheath. There is a gestat...
Kumar P, Timoney JF, Southgate HH, Sheoran AS.The nasal turbinates of 5 young horses were studied by light and scanning electron-microscopy. Stratified cuboidal epithelium lined the rostral part of the dorsal and ventral nasal turbinates of the vestibular region. The polyangular microvillus cells of this region were separated by linear depressions. The mid and caudal parts of the dorsal and ventral nasal turbinates and the rostral part of the ethmoturbinates were lined by pseudostratified columnar ciliated respiratory epithelium. Numerous cilia with dilated blebs on the ciliated cells concealed adjacent non-ciliated supporting cells and g...
Altunay H.The fine structure of the retinal pigment epithelium (RPE), Bruch's membrane and choriocapillaris was investigated by light and transmission electron microscopy in both the tapetal and non-tapetal fundus of the horse eye. In all locations, the RPE consisted of a single layer of low cuboidal cells. The epithelial cells were joined laterally by apically located tight junctions. These cells displayed numerous basal infoldings and abundant thin apical processes which enclosed the rod outer segments. The epithelial cell nuclei were large and located basally. Within the epithelial cells, smooth endo...
Ayala I, Gutierrez-Panizo C, Benedito JL, Prieto F, Montes A.The aim of this work was to record the modifications of the form and amplitude of the electrocardiographic tracings during growth using the Dubois system and to study its sensibility to these physiological changes. This work was carried out on 179 healthy, young and adult Spanish-bred horses (98 females and 81 males). One electrocardiogram (ECG) was obtained from each horse using the Dubois leads system. The bifid shape deflection of the P wave was generally more frequent than the simple one in animals at 4 months of age or older. Amplitudes of the P2 component and of the simple positive wave ...
Munroe G.Over 80 per cent of 169 neonatal thoroughbred foals had some part of the hyaloid artery present bilaterally and its degree of completeness, colour and character was statistically symmetrical. The complete artery was present in over 60 per cent of the foals. The incidence of the hyaloid artery and its completeness, colour and character were related to the age of the foal. The hyaloid system atrophies in the early stages of the neonatal period and generally its presence did not cause any significant ocular problems. The presence and morphology of the posterior pupillary membrane was highly corre...
Pfeiffer CJ, Levin M, Lopes MA.This investigation examined primarily epidermal specializations of the adult horse tongue by light, scanning and transmission electron microscopy. Samples were collected from seven regions of the normal tongue of various breeds of horse. The filiform papillae, present on the dorsal and lateral aspects but not the ventral aspect of the tongue, were short, slender and finger-like structures with variable-shaped terminae. The epidermal thickness and height of dermal ridges were reduced on fungiform and vallate papillae, but tissue architecture and keratinocyte ultrastructure of most of the lingua...
Hinrichs K, Schmidt AL.Horse oocytes were collected from an abattoir over a 15-mo period. After classification of follicle size and cumulus morphology, oocytes were either fixed immediately (0 h) or matured in vitro (24 h). There was no effect of season on the number of antral follicles present on the ovaries, or on oocyte maturation rate for any class of oocyte. The proportion of oocytes having condensed chromatin at 0 h increased with increasing follicle size. The oocyte maturation rate also increased with follicle size, and for follicles </= 20-mm diameter, was higher for oocytes initially having expanded cumu...
Olivares R, Michalland S, Aboitiz F.A cross-species morphometric study of the corpus callosum was performed in the rat, rabbit, cat, dog, horse, cow and human. Across species, the results indicate a strong, although less than linear, dependency of callosal size on brain weight. This relation tends to lose significance within species. This is consistent with other morphometric studies indicating a tendency to decrease the correlations between morphometric variables in within-species analyses as compared to between-species analyses. There are species differences in the relative size of some callosal segments particularly in the po...
Douglas JE, Thomason JJ.Circumferential and proximodistal variations in the morphology of the primary epidermal laminae of six neonatal and five adult equine feet were documented. Three parameters were quantified: interlaminar spacing, the orientation of the laminae with respect to the overlying wall, and any angulation within the laminae themselves ('internal angle'). In adult feet, the laminae were most closely spaced at the dorsum, the spacing increasing gradually towards the heels. In foals there was a non-significant trend for the dorsal laminae to be more widely spaced than those in more caudal parts of the foo...
Whitton RC, Murray RC, Buckley C, Goodship AE, Lekeux P.Training results in marked modelling of the subchondral bone of the carpus, but the effect of training on the subchondral bone of the distal tarsal joints is unknown. The aim of this study was to determine whether training influenced modelling of the third and central tarsal bones in Thoroughbred horses. Twelve untrained Thoroughbred horses were divided into 2 groups. Group 1 underwent a 19 week progressive training regimen on a high speed treadmill. Group 2 were walked for 40 min daily. Images of left tarsi were obtained by magnetic resonance imaging (MRI) with a 0.5 Tesla superconducting mag...
A 4-month-old Thoroughbred filly presented for abdominal pain was diagnosed with a T-shaped malformation of the ventral colon at exploratory laparotomy. Following resection and anastomosis of the large colon, no further episodes of abdominal pain occurred during a 12-month follow-up. Acute dehiscence of the linea alba occurred as a complication of the initial laparotomy, but was successfully managed following additional surgical repair. T-shaped malformation of the ventral colon has not previously been reported and is considered a congenital malformation of mesocolon formation.
Ludewig T.Corpora amylacea are present in all the mammary glands of the investigated animals (ewe, goat, and mares). Generally, they are comparable to the cow regarding to its distribution, frequency, size, morphological structure, and staining properties. Corpora amylacea occur most frequently in the ewe, and in non-lactating mammary glands. In lactating mammary glands they are mostly situated in the alveoles. During gestation they are located outside of the alveoles and in the interalveolar connective tissue. Only in very few cases corpora amylacea are found inside and outside of the alveoles in the s...
Sutherland RJ, Cambridge H, Bolton JR.A four-year-old Standardbred gelding presented with a 3.5 year history of intermittent epistaxis and spontaneous submucosal petechiae and ecchymoses in the nares and the mouth. Routine haematological and biochemical examinations were unremarkable. A thrombocytopathy was suspected when activated partial thromboplastin time, one stage prothrombin time, plasma fibrinogen and the platelet count were all normal. The patient's platelets failed to aggregate with serotonin, adenosine diphosphate, collagen (at 20 micrograms/ml) or the endoperoxide analogue U46619. Very high levels of collagen (100 micr...
Johnson L, Amann RP, Pickett BW.Changes within the equine seminiferous tubules during the cycle of the seminiferous epithelium were studied light and scanning electron microscopy (SEM). Once observed with SEM, tubules were sectioned and staged using light microscopy. As viewed by SEM, the weblike, spongy cytoplasm of germ cells or Sertoli cells in stages I and II extended over the entire height of the germinal epithelium. The cytoplasm of the basal portion of the germinal epithelium in stages III to VIII was similar to that in stages I and II. However, the cytoplasm which occupied the luminal third of the epithelium in stage...
Kalmykov NP.Morphological features of the teeth were studied in the three-toed horse Hipparion tchicoicum from the Pliocene of Western Transbaikalia (Russia). Several diagnostic signs of the Chicoi hipparion were described for the first time to provide criteria for distinguishing the taxon among other fossils of three-toed horses and estimating their real diversity at the final stage of their distribution in Inner Asia.
Leach D.This paper summarizes recommendations for terminology to be used in the description of quadrupedal locomotion and selected aspects of biomechanics. Directional terms and planes of the body (anatomical position, spatial reference systems), joint angulation, conformation, general locomotion terminology, phases of the stride and limb cycle (e.g. step, cadence) and terminology for the description of jumping are described.
Brito LF, Kelleman A, Greene LM, Raz T, Barth AD.A 5-year-old Arabian stallion was managed for breeding with fresh/extended semen during a period of 8 months with a resulting per cycle pregnancy rate of 26.3%. The stallion was in good health and no abnormalities of the reproductive tract were observed. Evaluation of several ejaculates revealed that sperm production and semen quality were mostly unchanged during the period of evaluation, that sperm production was normal and that semen quality was extremely poor. The most prevalent sperm defects were abnormal heads and mid-pieces. Most abnormal heads were microcephalic and/or tapered and consi...
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.
Han H, Wang A, Liu L, Zhao G, Su J, Wang B, Li Y, Zhang J, Wu B, Sun W, Hu S, Li S, Zhao L, Li X.Most hinnies (female donkey×male horse) and mules (female horse×male donkey) are sterile with few reports of equine fertile hybrids. The main cause of this sterility is thought to be a meiotic block to spermatogenesis and oogenesis. This study compared the developmental features of the testes and a histological analyses of spermatogenesis in a male hinny with those of a normal, fertile stallion and Jack donkey. Hinny testes showed a thicker tunica albuginea, fewer blood vessels and more connective tissue in the testis parenchyma than those of the stallion and Jack donkey. Although the mean n...
Malacarne BD, Martins RR, Paz CFR, Alves JVA, Dias LA, Cavalcante MA, Santos AM, Silva AGM, Leise BS, Carvalho AM, Faleiros RR.Although the external conformation of wild horse hooves has been proposed as an ideal model for domesticated modern horses, histological signs of laminitis have been reported among them. With the hypothesis that the lamellar tissue of horses of Iberian origin raised in semi-feral is healthier than those raised in an intensive management system (stall confinement and high-calorie diet intake), the objective was to compare their lamellar tissues. Lamellar tissue samples were taken from the forelimb hoof of eight domesticated Mangalarga Marchador (MM) horses and from six semi-feral Marajoara (MJ)...
Ono M, Akuzawa H, Nambo Y, Hirano Y, Kimura J, Takemoto S, Nakamura S, Yokota H, Himeno R, Higuchi T, Ohtaki T, Tsumagari S.A three-dimensional internal structure microscopy (3D-ISM) can clarify the anatomical arrangement of internal structures of equine ovaries. In this study, morphological changes of the equine ovary over the first 12 months of life were investigated by 3D-ISM in 59 fillies and by histological analysis in 2 fillies. The weight and volume of the paired ovaries initially decreased from 0 to 1 months to 2 to 3 months of age and then significantly increased at 8 to 12 months of age. The ovulation fossa was first observed around the 3rd month and became evident after the 6th month. The number of folli...
Diana A, Freccero F, Giancola F, Linta N, Pietra M, Luca V, Salamanca G, Cipone M, Chiocchetti R.Ultrasonographic morphometry of wall layers is commonly used in veterinary patients with suspected small intestinal disease, however published studies comparing this method with histopathology in horses are limited. This prospective, methods comparison study compared the qualitative and quantitative characteristics of small intestinal wall layers using ex vivo high-frequency ultrasound versus histopathology in a sample of 16 horses. Transverse section images of duodenum, distal jejunum, and ileum were acquired with a high-frequency linear transducer (7-15 MHz). Transverse histological cryosec...
Medeiros BR, Garbade P, Seixas L, Peripolli V, McManus C.The aim of this study was to evaluate genetic parameters for subjective scores given at the Brazilian Sport Horse (BSH) Stallion Approval by estimating heritability (h) for morphological, gait, and jumping traits and genetic correlations (γ) among the functional ones and by verifying selection feasibility. The analysis included 1179 complete evaluations from 294 horses, by 4.26 ± 0.96 judges. Each trait was evaluated using mixed models in SAS® v9.2, considering the individual as a random effect. Variance components and genetic parameters were obtained by single and two-trait animal mode...
Pavone S, Mandara MT.The interstitial cells of Cajal (ICC) play a key role in the control of intestinal motility and have been implicated in several human gastrointestinal dysmotility syndromes, in equine grass sickness and in other intestinal disorders where a significant reduction in ICC density was observed. Objective: To investigate the density of ICC in clinically normal horses, ICC c-Kit expression was evaluated by image analysis in order to obtain numerical data. Methods: Intestinal samples from the jejunum to small colon from 5 clinically normal horses were studied. Immunohistochemical labelling of ICC was...
Alm H, Hinrichs K.The period of protein synthesis necessary for meiotic maturation in horse oocytes initially having compact or expanded cumulus cells was studied. Oocytes incubated in the presence of cycloheximide after 0, 4, 8, 12 or 16 h maturation in vitro (total incubation time 24 h) were matured for 24 h, or were incubated with cycloheximide for 24 h and then matured for 24 h. Incubation with cycloheximide from 0 h was effective in suppressing maturation (no significant increase in maturing oocytes compared with controls fixed directly after removal from the follicle) in both expanded and compact groups a...
Silva DM, Holden SA, Lyons A, Souza JC, Fair S.The aim of the present study was to assess the effect of the addition of docosahexaenoic acid (DHA) on the in vitro quality of cooled and frozen-thawed stallion semen. In Experiment 1, semen from 10 stallions was collected (three ejaculates per stallion). Semen was diluted to 100×106 spermatozoa mL-1 with 0.02mM vitamin E (VE) and 0, 1, 10 or 20ng mL-1 DHA and frozen. Semen was thawed and total motility (TM), rapid progressive motility (PM), acrosome integrity, membrane fluidity and morphology were assessed. In Experiment 2, semen from three stallions was collected (three ejaculates per stall...
Bartolomé E, Milho S, Prazeres J.The International Equestrian Federation (FEI) ranks horses participating in dressage tests resulting in a prestigious list where equestrians would like to see their horses ranked. The main objective of this study was to analyze morphological and genealogical differences between Lusitano horses (LPB) participating at international events and those ranked by FEI, considering pedigree information. For this study, 324 LPB participating in dressage competitions were analyzed. Thirty-two were ranked at FEI. The pedigree was reconstructed up to 1148 animals. For analyses, the complete pedigree (CP) a...
Watanabe T, Hosaka Y, Yamamoto E, Ueda H, Tangkawattana P, Takehana K.The Golgi tendon organ (GTO) is an encapsulated fusiform mechanoreceptor siding in the musculo-tendinous junction of many animal species. Inhibitory function of afferent nerve fibers distributed from nearby motor units, the organ responds to active tension exerted onto the muscle. The morphological features of the equine GTO have not yet been elucidated. Additionally, there is some controversy regarding to the existence of the GTO in the equine superficial digital flexor tendon (SDFT). Therefore, immunohistochemistry and immunoelectron microscopy using alcian blue (pH 2.5) staining and the sil...
Dongus H, Beelitz P, Schöl H.The female reproductive system of Thelazia lacrymalis (Nematoda: Thelaziidae) was investigated by light and scanning electron microscopy (SEM) with regard to the developmental stages and the stage deposited by the gravid nematode. Female T. lacrymalis have a didelphic and opisthodelphic type of reproductive system with paired ovaries, oviducts and uteri and a single vagina and vulva. Round and spindle-shaped primary oocytes are documented within the ovaries and oviducts, respectively. The distal part of each uterus provides a fertilization chamber filled with spermatozoa, followed by a sphinct...
Huhtinen M, Reilas T, Katila T.The pregnancy rate is lower in mares inseminated at the first post-partum (p.p.) oestrus (40-50%) compared with pregnancy rates in subsequent oestrous cycles (55-65%). The causes of the lowered pregnancy rate are not fully understood. The aim of the present study was to examine if embryonic defects could be one of the reasons for lowered pregnancy rate. A total of 23 p.p. and 14 non-lactating control mares were flushed 7 days after detection of ovulation. Embryo recovery rate was 48% and 71% in p.p. and control mares, respectively (p = 0.16). Embryos were photographed, measured, graded and sta...
Teifke JP.From 932 equine skin lesions 421 were diagnosed as sarcoids (about 45%). The most common locations were the ventral body regions, head, neck and sites of thin skin. Most often the fibroblastic type, less frequently the mixed type and most infrequent the verrucous type of sarcoid were diagnosed. Detection of BPV-DNA was performed by polymerase chain reaction (PCR) using an oligonucleotide primer pair located in the E5-open reading frame. DNA of BPV 1 and BPV 2 could be differentiated by digestion with restriction endonucleases. In 97 out of 108 sarcoids BPV-DNA was detected by PCR. Most samples...
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...
Ghezelsoflou H, Hamidi P, Gharahveysi S.The Iranian Turkoman horse is considered one of the major categories of Iranian native horses. The aim of this research was to study the genetic and nongenetic factors affecting body conformation traits in Iranian Turkoman horses. For this, measurements were performed on body conformation traits of 121 horses. To study the effect of nongenetic factors, the Lsmeans procedure was used. Variance components and heritability were estimated by restricted maximum likelihood method (REML) and AI-REML convergence algorithm. The standard deviation was estimated to be 7.04 cm for croup depth and 2.08 cm ...
Muylle S, Simoens P, Lauwers H.The distribution of intratubular (peritubular) dentine was studied by scanning electron microscopy in 12 equine incisor teeth. High levels of intratubular dentine were found in the peripheral regions of the dentine. In these areas, a marked asymmetry occurred, as intratubular dentine was predominantly deposited onto the side of the dentinal tubular walls nearest to the dentino-enamel junction. The quantity and asymmetry of intratubular dentine were reduced towards the centre of the tooth. The significance of these variations in the amount and distribution of intratubular dentine between the di...
Strootmann T, Spitzbarth I, Della Tommasa S, Brehm W, Köller G, Troillet A.Research and provision of data on macrophages by cytological synovial fluid analysis and light microscopy in horses with septic arthritis MATERIAL AND METHODS: Records of 167 synovial fluid samples were evaluated and subdivided into different groups: (1) non-septic, (2) haematogenous septic arthritis in foals and (3) traumatic/iatrogenic septic arthritis. The effect of joint lavage on synovial fluid cytology and on the occurrence of macrophage phenotypes was investigated. Results: Regardless of aetiology and age of the horse, macrophage concentrations in synovial sepsis are decreased to a medi...
Lançoni R, Celeghini ECC, Gonella-Diaza AM, Júnior VG, de Carvalho CPT, Zoca GB, Garcia-Oliveros LN, Batissaco L, Oliveira LZ, de Arruda RP.This study aimed to assess the semen ubiquitin levels of stallions with good (GF) and poor semen freezability (PF) and to evaluate the relationship between sperm ubiquitination and sperm morphological defects. Five ejaculates from eight adult stallions (n = 40) were collected and cryopreserved. Then, the ubiquitin level in equine sperm cells was assessed by immunohistochemistry with epifluorescence microscopy, and sperm morphology was assessed by differential interference contrast microscopy. Sperm cells were classified according to the intensity (classification 1: from I to IV; I = very l...
Dymock DC, Pauwels FE.To describe key morphological attributes of the third metacarpal bone (Mc3) of horses and to determine whether or not the symmetry of the Mc3 varied significantly between limbs of the same horse. Methods: Ten pairs of metacarpi were collected from slaughter facilities. The age and breed of the horses were recorded. Fixed points and axes that could be easily reproduced between bones were identified on high-quality photographic images of each bone. Using image analysis, three angles were measured. Angle gamma measured the rotation around the long axis of the diaphysis of Mc3, angle delta the ang...
Mouguelar H, Díaz T, Borghi D, Quinteros R, Bonino F, Apichela SA, Aguilar JJ.The objectives of this work were to describe some morphometric characteristics and to establish quantitative parameters of different regions of the equine oviductal mucosa from the isthmus, ampullary-isthmic junction (AIJ), and ampulla. Twenty-one mixed-bred mares were used for this study. Mares were selected in the following reproductive phases: anestrus, estrus, and diestrus. The left oviducts were examined with light microscopy, and rights ones were studied through the intraoviductal molds. The isthmus showed the smallest luminal area, mucosal area, epithelial perimeter, and luminal diamete...
Russo D, Castellani G, Chiocchetti R.Spinal ganglion (SG) neurons are subdivided, on the basis of their cytoplasmic aspect at light and electron microscopy, into dark (D) and light (L) neurons. Numerous efforts have been made to find specific markers able to identify D and L neuronal cytotypes. The isolectin B4 (IB4), utilized to identify nonpeptidergic D neurons in mice, unfortunately, has not proved as effective in other species. The 200-kDa neurofilament protein (NF200) is considered as a typical marker of L neurons in the rat, cat, and chick. The aim of this study was to analyze the histological, morphometric, and neurochemic...
