Microscopy in equine research involves the use of various microscopic techniques to study the cellular and subcellular structures of horses. This field encompasses the examination of tissues, cells, and microorganisms to gain insights into equine health, disease mechanisms, and physiological processes. Techniques such as light microscopy, electron microscopy, and fluorescence microscopy are employed to observe and analyze samples at high magnification, providing detailed information on morphology and pathology. Microscopy aids in the diagnosis of diseases, identification of pathogens, and evaluation of cellular responses to treatments. This page compiles peer-reviewed research studies and scholarly articles that explore the applications, methodologies, and findings of microscopy in the study of equine biology and medicine.
Dabareiner RM, Snyder JR, Sullins KE, White NA, Gardner IA.Intramural vascular patterns of the jejunum and colon were evaluated during ischemic strangulation obstruction (ISO, 70 minutes) and subsequent reperfusion (60 minutes) in 7 adult anesthetized horses. Microvasculature of experimental and control segments was described by comparison of results from microangiography, light microscopy, and scanning electron microscopy of vascular replicas. Experimental and control segments with isolated vascular arcades were removed either immediately after the experimental period or after 60 minutes of reperfusion. Blood was flushed from the vascular system by u...
Bruyas JF, Bézard J, Lagneaux D, Palmer E.Sixteen embryos were recovered nonsurgically at day 6.5 after induced ovulation from Welsh pony mares and were evaluated for cellular changes that occur because of exposure to the cryoprotectant with or without the freeze and thaw process. Day 6.5 horse embryos were either (i) frozen and thawed using glycerol as cryoprotectant (n = 6), (ii) given only the glycerol treatment (n = 5), or (iii) washed in phosphate-buffered saline (PBS) the same number of times as in the glycerol treatment (n = 5). After treatments, embryos were incubated in Minimum Essential Medium (MEM), supplemented with BSA, g...
West JB, Mathieu-Costello O, Jones JH, Birks EK, Logemann RB, Pascoe JR, Tyler WS.Bleeding into the lungs in thoroughbreds is extremely common; there is evidence that it occurs in essentially all horses in training. However, the mechanism is unknown. We tested the hypothesis that exercise-induced pulmonary hemorrhage (EIPH) is caused by stress failure of pulmonary capillaries. Three thoroughbreds with known EIPH were galloped on a treadmill, and after the horses were killed with intravenous barbiturate the lungs were removed, inflated, and fixed for electron microscopy. Ultrastructural studies showed evidence of stress failure of pulmonary capillaries, including disruptions...
Takeda S, Ohta M, Ebina S, Nagayama K.Horse L-ferritin cDNA was cloned from horse liver, and the base sequence was determined. The L-ferritin was expressed using pTZ18U encoding lac promoter, and found to possess an additional 8-amino acid sequence at the N-terminus as compared with commercially obtained horse spleen (natural) ferritin. It was determined that there was Pro at position 94 in both the recombinant and natural L-ferritin, although it was previously reported that Leu was in this position in the natural species. Transmission electron microscopy showed that this recombinant ferritin formed a 24-mer shell.
Ohmuro K, Okada K, Satoh A, Murakami K, Satake S, Asahina M, Numakunai S, Ohshima K.A thoroughbred horse, gelding, gray color, aged 19 years old had cutaneous melanomas from the root to the middle of the tail, and throughout the connective tissues of the whole body. Histologically, the tumors were diagnosed as mature melanotic melanomas characteristically deposited with abundant melanin pigment. Examined with an electron microscope, melanosomes were electron opaque without internal structure (stage IV), or as mature granular and lamellar types. Most of them were fused with each other, and formed compound melanosomes, which was similar to internal melanin aggregates in shape. ...
Casey PJ, Hillman RB, Robertson KR, Yudin AI, Liu IK, Drobnis EZ.An acrosomal staining technique that can differentiate between living and dead sperm was developed for equine sperm. The fluoresceinated lectin Pisum sativum agglutinin (FITC-PSA) was used to identify the presence or absence of acrosomal contents, while the supravital nuclear dye Hoechst 33258 (H258) was used to assess viability. The accuracy of the FITC-PSA acrosomal stain was tested by comparing the percentage of sperm that had lost their acrosomal contents, detected by the staining method, with that detected by transmission electron microscopy (TEM). Following capacitation in vitro, the acr...
Stockert JC, Trigoso CI, Tato A, Ferrer JM.The structure of specific granules from horse eosinophil leukocytes is still largely unknown. In this work, electron microscopical studies of horse eosinophils reveal that the large cytoplasmic granules contain an external membrane, a matrix of less density, and a dense (non crystalline) core. Round vacuolar inclusions of matrix materials were often observed within the cores. Horse eosinophil granules showed a considerable heterogeneity, and three morphological types could be identified according to structural features of the core and matrix.
Wisner ER, O'Brien TR, Lakritz J, Pascoe JR, Wilson DW, Tyler WS.Complete thoracic radiographic examinations were performed on 7 horses ranging in age from 24 to 60 months, followed by in-situ lung fixation. Radiographs were examined by 3 radiologists for the presence, degree and distribution of generalised pulmonary patterns within a region of interest in the caudodorsal lung. Pulmonary tissue was obtained from 12 sites within a designated volume of interest in the caudodorsal lung, corresponding to the area of interest evaluated radiographically, and examined for the presence, character and severity of microscopic lesions. Radiographic findings within the...
Beech J, Lindborg S, Braund KG.Potassium concentrations were measured in semimembranosus muscle, plasma and erythrocytes, and the urinary fractional excretion determined in normal horses and those that had chronic intermittent exercise-associated rhabdomyolysis. Muscle from the rhabdomyolysis horses was also evaluated microscopically. The horses with rhabdomyolysis had a lower muscle potassium concentration on a dry weight basis. Although the wet weight potassium content was also lower, the difference was not significant. Urinary fractional excretion of potassium (and also sodium and chloride) did not differ significantly b...
Johnson CM, Cullen JM, Roberts MC.Ten ponies (160-250 kg, ages 17 months to 20 years) developed severe diarrhea within 24 hours of castor oil administration (2.5 ml/kg orally). The diarrhea was most severe between 24 and 48 hours post-dosing and subsided by 72 hours. Ponies were euthanatized at 24, 48, and 72 hours post-dosing and intestine was evaluated histologically and ultrastructurally. Twenty-four hours after dosing, the mucosa of the cecum and ventral colon had extensive superficial epithelial erosion and neutrophil infiltration. In the ileum, the epithelium of villous tips was separated from the lamina propria. Scannin...
Oikawa M, Katayama Y, Yoshihara T, Kaneko M, Yoshikawa T.The morphology of the arteries in the uterine wall was studied in three multiparous aged mares that had suffered repeated pregnancy failure. The uterine wall arteries exhibited elastosis of the intima or adventitia, or both, resembling "physiological pregnancy sclerosis". In areas affected by elastosis, degeneration of the pre-existing elastic fibres and increased glycosaminoglycans were frequently observed. Newly formed elastic fibres were not evident. Delayed resorption due to disordered metabolic turnover of the elastin was thought to be an important factor in the pathogenesis of the arteri...
Riggs CM, Lanyon LE, Boyde A.A novel technique for determining the collagen fibre orientation pattern of cross-sections of cortical bone was used to study mid-diaphyseal sections from the equine radius. Several in vivo strain gauge studies have demonstrated that this bone is loaded in bending during locomotion in such a way that the cranial cortex is consistently subjected to longitudinal tensile strains and the caudal cortex to longitudinal compressive strains. Twenty-three radii from 17 horses were studied. All the bones obtained from adult horses exhibited a consistent pattern of collagen fibre orientation across the c...
Massanyi L, Janisch R.According to the distribution of IMP, three different regions can be recognized on PF of the post-acrosomal plasma membrane of bull, ram, and boar spermatozoa. They are: (1) a region with linear aggregation of IMP, (2) a region with fewer and scattered IMP, and (3) a region with more numerous IMP. In the last two regions IMPs are randomly distributed or a clustering of certain particles is visible. In stallion spermatozoa the last two areas are undistinguishable. There are evident interspecies differences in the arrangement of linear aggregations of IMP which are characteristic for each specie...
Arrighi S, Romanello MG, Domeneghini C.The ultrastructure of the epithelial lining of the ductuli efferents and the ductus epididymis in the horse (Equus caballus) is described. Several types of cells can be distinguished: ciliated and non-ciliated cells make up the epithelium of the ductuli efferents, whereas principal, apical and basal cells are found in the ductus epididymis. The observations are compared with those made in other species, in particular in the donkey (Equus asinus), and the possible functional roles of the different cell types are discussed.
Hinrichs K, Schmidt AL, Friedman PP, Selgrath JP, Martin MG.The chromatin configuration of resting horse oocytes and the time course of in vitro oocyte maturation was characterized using a fluorescent, DNA-specific label. Oocytes were classified as having either compact (CP) or expanded (EX) cumuli at the time of collection. Centrifugation of oocytes was effective in allowing visualization of the germinal vesicle. Two main chromatin configurations were found in oocytes known to have a germinal vesicle: condensed chromatin (CC), in which the chromatin formed a dense mass surrounding the nucleolus; and fluorescing nucleus (FN), in which the entire nucleu...
Leach DH.Cells of the intertubular horn of the stratum medium of the equine hoof wall are joined by three types of junctions. Desmosomes and gap junctions were present in all strata. Septate-like junctions and an intercellular line were seen in the distal stratum spinosum subsequent to extrusion of the contents of membrane-coating granules. At a later stage of keratinization, non-membrane-bound acid phosphatase reaction product appeared to leak into the intercellular space except into areas occupied by septate-like junctions and the intercellular line. It is proposed that the formation of septate-like ...
Cummings JF, de Lahunta A, Summers BA, Mohammed HO, Divers TJ, Valentine BA, Trembicki-Graves K.Equine motor neuron disease (EMND) is a sporadic, progressive neurodegenerative disorder that has been identified recently in horses of different breeds in North America. The cause is unknown. Pathologic changes which occur in spinal and certain brain stem motor neurons include chromatolysis, swelling, neurofilamentous accumulation, and development of eosinophilic cytoplasmic inclusions. Punctate eosinophilic inclusions, the type usually encountered in degenerating neurons, resembled Bunina bodies at the light microscopic level, but differed in their ultrastructural composition. These and less...
Schöl H, Beelitz P, Gothe R.Trichomonads of the oral cavity were found in 9 of 60 investigated horses. Apart from dental tartar, the oral cavity showed no clinical signs in all positive horses. The clinical investigation of these horses additionally revealed colic in 4 and coughing in 4 horses as well as lumbago in 1 animal. By means of scanning electron microscopy the trichomonads were shown to be round or piriform with an average length of 7.6 microns and greatest width of 6.3 microns. They had 4 anterior flagella with an average length of 8.3 microns, an undulating membrane measuring 8.7 microns with no trailing flage...
Kotzé SH, Soley JT.Spirally arranged bundles of sub-endothelial smooth muscle enfold the small to medium-sized submucosal veins in the equine ileocecal junction. The muscle bundles, accompanied by the endothelial lining, bulge into the lumen of the vessels, partly occluding the latter. Transmission electron microscopy of the muscle cells reveals features consistent with vascular smooth muscle ultrastructure. It is proposed that the throttling effect of the muscle bundles causes engorgement of the submucosal venous plexus, which then assists in the closing of the ileocecal orifice.
Atwal OS, Singh B, Staempfli H, Minhas K.The pulmonary intravascular macrophages (PIMs) have been described in several species of animals. This study demonstrates for the first time that the equine lung has PIMs as resident phagocytes in its microvasculature. Their salient features such as globular surface coat, structures of the endocytic pathway, and related cell organelles closely resemble those of the calf, goat, and sheep. The exquisite organization of the coat globules in the form of a linear chain was structurally similar to the lipolytic lipase and the heparin-sensitive globular coat from PIMs of calf, goat, and sheep. Monast...
Machida N, Nakamura T, Kiryu K, Haramaki S, Too K.A 20-year-old pony mare with persistent ventricular tachycardia (VT) was examined cardiopathologically. At necropsy, the heart was enlarged and rounded with both ventricular dilatation. In a longitudinal section of the ventricular septum, a large grayish white patchy lesion (5 x 25 mm) was detected in the relatively higher portion. Microscopically, the lesion was extensive myocardial fibrosis located in the vicinity of the proximal part of the left bundle branch. Partially the fibrotic lesion was in contact with the branch. Such a lesion might play an important role in creating a suitable back...
Henninger DD, Snyder JR, Pascoe JR, Dilling GW.The normal microvascular permeability of the ascending colon in horses and the microvascular permeability of that segment after ischemia and reperfusion were investigated. Microvascular permeability was estimated by the ratio of lymphatic protein to plasma protein concentration (Cl/Cp) at high lymph flow rates in 8 adult horses in 2 equal groups: normal and ischemic (2-hour period). Lymphatic flow rates and lymph and plasma protein concentrations were determined. Intestinal biopsy specimens were obtained at the end of each experiment. Flow independent values were selected and compared by one-w...
Granstrom DE, Alvarez O, Dubey JP, Comer PF, Williams NM.Schizonts of Sarcocystis neurona were identified microscopically in hematoxylin-eosin-stained spinal cord sections from 2 native Panamanian horses that exhibited clinical signs of equine protozoal myelitis (EPM). Spinal cord homogenate from a third Panamanian horse with EPM was inoculated onto monolayers of cultured bovine monocytes (M617). Intracytoplasmic schizonts containing merozoites arranged in rosette forms surrounding a central residual body first were observed 13 wk postinoculation. Parasites divided by endopolygeny and lacked rhoptries. Schizonts from each horse reacted with Sarcocys...
Snyder JR, Pascoe JR, Olander HJ, Harmon FA, Hinds DM, Vatistasa NJ, Tyler WS.The ultrastructural injury that develops sequentially in the ascending colon during experimentally induced ischemia was examined in 6 halothane-anesthetized horses. Colonic ischemia was created by 2 types of vascular occlusion 24 cm proximal and distal to the pelvic flexure. In all horses, transmural vascular compression was created. The colonic venous circulation was obstructed in 3 horses, whereas in the other 3 horses, arterial and venous circulation was obstructed. Two additional horses were anesthetized as controls for determination of any morphologic alterations associated with the exper...
Roperto F, Damiano S, De Vico G, Maiolino P, Restucci B.This paper presents some ultrastructural details of cilia from the ciliated tracheal epithelium of healthy horses. By using a new fixation method, the Authors were able to describe minute details, some of which have been only rarely observed in other species and mostly by means of the freeze-etch technique (i.e. electron dense particles of ciliary necklace). The Authors justify the need to investigate the ultrastructural details of cilia in various species since the minute morphological differences might be functionally significant.
Pfeiffer CJ, Dabareiner RM.Investigation of the duodenal submucosal glands of Brunner in the horse for the first time at the ultrastructural level has clarified some of the unique features of these equine glands. The horse is one of the very few mammals in which Brunner's glands are comprised of both mucous and serous tubuloacinar glands. Although the ultrastructural differences between the serous and mucous cell types are marked, particularly with respect to secretory granules and rough endoplasmic reticula, these cell types closely correspond to serous and mucous cells in the upper digestive system of other mammals. A...
Kayar SR, Hoppeler H, Armstrong RB, Laughlin MH, Lindstedt SL, Jones JH, Conley KR, Taylor CR.The mean minimal capillary transit time was estimated in muscles of various animals using a combination of physiological and morphometric methods. Radioactive microspheres were injected intravascularly in various animals running on a treadmill at maximum oxygen consumption rate (VO2,max) to label blood flow to individual muscles. The muscles were then removed and preserved by standard methods for electron microscopy. The volume density of mitochondria was measured to assess muscle oxidative capacity. Capillary densities in muscle cross-sections, capillary diameters and tortuosities were incorp...
Geyer C, Hafner A, Pfleghaar S, Hermanns W.Six canine, one feline and one equine granular cell tumours (GCTs) were investigated electron microscopically and immunohistochemically. The tumours were tested for reactivity with monoclonal antibodies against vimentin and desmin and with polyclonal antibodies against cytokeratin, S-100 protein, glial fibrillary acidic protein (GFAP) and neuron specific enolase (NSE). All GCTs were characterized by their PAS positive cytoplasmic granules in light microscopy, which in electron microscopy appeared as lysosome-like granules. In each case two canine GCTs were stained by the antibody against cytok...
Dart AJ, Snyder JR, Harmon FA.The microvascular circulation of the descending colon was studied in 5 adult horses, using microangiography and light microscopy combined with gross studies and scanning electron microscopy of vascular replicas. After heparinization, horses were euthanatized, and 3 segments of the descending colon and its mesentery containing 1 vascular arcade were removed from each horse. The fecal balls were gently massaged from the lumen, and the blood was flushed free of the circulation with isotonic NaCl. In 5 segments, the vascular system was injected with a modified radiopaque medium and evaluated radio...
Dart AJ, Snyder JR, Julian D, Hinds DM.The microvascular anatomic features of the small intestine was described by correlating results of microangiography, light microscopy, gross studies, and scanning electron microscopy of vascular replicas in 14 horses. After heparinization, the horses were euthanatized, a length of jejunum was transected, and blood was flushed free of the circulation, using isotonic NaCl solution. In six horses, the circulatory system was perfused with a modified radiopaque medium and evaluated radiographically. These sections were then evaluated by standard histologic methods. Sections from 8 horses were perfu...
Walter I, Tschulenk W, Budik S, Aurich C.The present study gives a detailed ultrastructural description of equine conceptuses at Day 14 (n = 2) and Day 16 (n = 3) after ovulation. Whereas on Day 14 only primitive structures were seen, on Day 16 neurulation and formation of mesodermal somites had taken place. The ectoderm of the embryo itself and the surrounding trophoblast ectodermal cells were characterised by specific cell surface differentiations. At the embryonic ectodermal cell surface (14 and 16 days) remarkable protruded and fused cytoplasmic projections were seen, typically associated with macropinocytotic events involved in ...
Apprich V, Spergser J, Rosengarten R, Hinterhofer C, Stanek C.Horn samples were taken from the hooves of eight horses with clinical signs of equine onychomycosis in at least one hoof capsule. None of the horses had a documented mycological history. The predominant alterations of the horn capsules were sand cracks, white line disease, brittleness (especially around the nail holes), parakeratosis and bruising. The horn samples were stored in sterile tubes for transportation and transferred onto Sabouraud Dextrose Agar and dermatophyte test agar for mycological examination within 6 h. Fungal cultures were incubated for 30 days at room temperature. Funga...
Zambrano M LA, Kilroy D, Kumar A, Gilchrist MD, Ní Annaidh A.Wormian (intrasutural) bones are small, irregular bones, that are found in the cranial sutures of the skull. The occurrence of Wormian bones in human skulls has been well documented but few studies have detected the presence of such bones in domestic animals. Although some research has linked the presence of Wormian bones to bone pathology, its anatomical significance in healthy individuals is not known. To the best of our knowledge, no previous study has examined the biomechanical features of Wormian bone. This study uses microCT imaging of the parietal bone region to determine the frequency ...
Faramarzi B, Lantz L, Lee D, Khamas W.The digital cushion (DC) plays a role in absorbing and dampening forces applied to the foot and therefore supports internal structures such as navicular bone; yet, its architecture is not well-known. The goal of this study was to characterize the microanatomical structure of the DC in horses with clinically sound hooves. Both forefeet from the cadavers of 12 adult Quarter horses were cut and sectioned and samples of the following 4 regions of the DC were obtained: axial proximal (AxProx), axial distal (AxDis), abaxial lateral (AbxLat), and abaxial medial (AbxMed). The samples were processed an...
Kilic S, Dixon PM, Kempson SA.Ultrastructural examinations of defined 3 equine enamel types termed equine (Eq.) Types 1, 2 and 3 enamel, according to the transverse appearance of their enamel prisms and the amount and appearance of their interprismatic enamel. Eq. Type 1 enamel contained alternating rows of oval shaped prisms and thick interprismatic enamel plates, and was found adjacent to the amelodentinal junction. Eq. Type 2 enamel consisted of circular, 'keyhole' to 'horseshoe' shaped prisms with little or no interprismatic enamel and was located adjacent to the amelocemental junction. Eq. Type 3 enamel was composed o...
El-Gameel SM, Al-Mokaddem AK, Salaeh NMK, Attia MM.Equine gastrointestinal tract is infected with () which is highly pathogenic parasite for its harmful effect on cranial mesenteric artery during its migration. So, this study was applied for identification of in donkeys ultramorphologically and molecularly. In addition to, detection of the pathological effect of larval stage of on the mesenteric arterial system using histopathology and immunohistochemistry. During the period from September to December; 2019, 60 male and 20 female donkeys at the Giza Zoo was postmortem examined. adults and larvae were collected from the large intestine and ...
Driessen B, Zarucco L, Steffey EP, McCullough C, Del Piero F, Melton L, Puschner B, Stover SM.The volatile anaesthetic sevoflurane is degraded to fluoride (F-) and a vinyl ether (Compound A), which have the potential to harm kidney and liver. Whether renal and hepatic injuries can occur in horses is unknown. Cardiopulmonary, biochemical and histopathological changes were studied in six healthy thoroughbred horses undergoing 18 h of low-flow sevoflurane anaesthesia. Serum F- concentrations were measured and clinical laboratory tests performed to assess hepatic and renal function before and during anaesthesia. Necropsy specimens of kidney and liver were harvested for microscopic examinat...
AbouLaila M, Allam T, Roshdey T, Elkhatam A.Strongylus vulgaris has high pathogenicity to equines. It causes aneurysm and thrombosis in the arteries particularly an anterior mesenteric artery, that is fatal to equines. In this study, we aimed to diagnose microscopically the natural infection of donkeys with Strongylus vulgaris from Sadat City, Minoufiya Governorate, Egypt. Fecal egg culture was used after the diagnosis of strongyle eggs to identify the species. Hematological and biochemical parameters were assessed. Adult worms were collected after post mortem examination of the infected animal. The sequence of ITS-2 was used to confirm...
Yasui T, Tsukise A, Miura T, Fukui K, Meyer W.Cytochemistry of glycoconjugates in the apocrine glands in the scrotal skin of the horse was studied using cytochemical methods for electron microscopy, particularly lectin cytochemistry. The secretory cells possessed a variable number of secretory vesicles, a well-developed Golgi apparatus, and abundant cisternae of the rough endoplasmic reticulum. Additionally, the basolateral plasma membrane formed numerous interdigitating folds. Glycoconjugates with vicinal diol groupings were present predominantly in the secretory vesicles, the Golgi apparatus, the surface coat of the plasma membrane, and...
Zahoor J, Kashif M, Nasir A, Bakhsh M, Qamar MF, Sikandar A, Rehman A.Trypanosomiasis is one of the severe pathogenic infections, caused by several Trypanosoma species, affecting both animals and humans, causing substantial economic losses and severe illness. The objective of this study was to determine the molecular diagnosis and the risk factors associated with trypanosomiasis in District Jhang, Punjab, Pakistan. For this purpose, blood samples were randomly collected from 200 horses. A predesigned questionnaire was used to collect data on risk factors before the sample collection. The microscopy examination through Giemsa staining, formol gel test and PCR tec...
Simpson CF, Neal FC.Four splenectomized ponies were infected with Babesia equi. Two ponies were not treated, and two were treated with 5 mg of imidocarb/kg of body weight when 20% of their erythrocytes were parasitized. The nucleus of the parasite in erythrocytes from blood smears of nontreated ponies was roundish, deep red-staining, and usually composed two-thirds of the organism. The parasite in erythrocytes from blood smears of treated ponies was swollen and vacuolated except for an area just beneath the plasma membrane where the compressed nucleus was marginated, elongated, and clumpy. Parasites in erythrocyt...
Weiss DJ, Evanson OA.To determine the potential usefulness of tests for detection of platelet activation and platelet-leukocyte aggregates in horses. Methods: Blood from 3 healthy Thoroughbreds. Methods: Microscopic and flow cytometric assays were used to evaluate spontaneous platelet aggregation, platelet activation, and platelet-leukocyte aggregates. Platelet activation was detected by evaluation of binding of anti-human fibrinogen to unactivated and ADP-, thrombin-, thrombin agonist receptor peptide-, and platelet activating factor-activated platelets. Platelet-leukocyte aggregates were evaluated microscopicall...
Neto da Silva AC, Costa AL, Teixeira A, Alpoim-Moreira J, Fernandes C, Fradinho MJ, Rebordão MR, Silva E, Ferreira da Silva J, Bliebernicht M....In older mares, increasing collagen fibers (fibrosis) in the endometrium and oviduct predisposes to sub-fertility and infertility. In this study, (i) gene transcription of collagen (qPCR: COL1A1, COL1A2, COL3A1, COL5A1); (ii) total collagen protein (hydroxyproline); (iii) collagen distribution (Picrosirius red staining; polarized light microscopy); and (iv) microvascular density (Periodic acid-Schiff staining), were evaluated in mares' placenta, and related to mares age, and placenta and neonate weights. Samples were collected from the gravid horn, non-gravid horn, and body of the placenta fro...
Du Toit N, Kempson SA, Dixon PM.Ten normal cheek teeth (CT) were extracted at post mortem from donkeys that died or were euthanased for humane reasons. Decalcified histology was performed on three sections (sub-occlusal, mid-tooth and pre-apical) of each tooth, and undecalcified histology undertaken on sub-occlusal sections of the same teeth. The normal histological anatomy of primary, regular and irregular secondary dentine was found to be similar to that of the horse, with no tertiary dentine present. Undecalcified histology demonstrated the normal enamel histology, including the presence of enamel spindles. Scanning elect...
Klomkleaw W, Kasashima Y, Fuller GA, Kobayashi A, Yoshihara T, Oikawa MA, Izumisawa Y, Yamaguchi M.An anatomical study of horse lumbrical muscle (Lm) was carried out by light and electron microscopy in combination with immunochemical and cytochemical methods. Paraffin sections were subjected to haematoxylin and eosin (H & E) and Masson's trichrome staining for morphometric analysis. Paraffin sections were also used for immunostaining by anti-PGP 9.5 for reaction with nerve-protein associated-structures, anti-heat-shock protein 70 (hsp 70) for detection of gene expression changes, anti-fast myosin for the determination of muscle fibre types, and for detection of apoptotic gene expression...
Guo X, Aoyama M, Sugita S.Three optic nerves (L1, R2, R3) 12-18 mm behind the eyeball of the horse (Thoroughbred) were investigated quantitatively under light and electron microscopes. Thin sections at the thickness of 0.35 microm were cut, stained by toluidine blue and observed under the light microscope. The areas of the optic nerve and the axon bundles were 20.03 +/- 1.04 and 16.59 +/- 0.79 mm2 (mean +/- SD, n=3), respectively. The axon numbers for optic nerve L1, R2 and R3, estimated from light micrographs, were about 481 x 10(3), 543 x 10(3), and 494 x 10(3), respectively. Axons of optic nerve L1 were also counted...
Johnson L, Amann RP, Pickett BW.Spermatozoa from four regions of the epididymis and from ejaculated semen were evaluated for their resistance to cold shock, progressive motility, and structural stability. Spermatozoa were incubated at 38 C and their percentage of eosinophilia was compared with that of spermatozoa cooled to 0 C in 2 minutes, 10 C in 12 minutes, or 4 C in 22 minutes. Spermatozoa motility was estimated visually under phase-contrast microscopy and was recorded by cinematography. Structural stability of spermatozoa incubated in 0.05 M sodium borate buffer, 0.035 M sodium dodecyl sulfate (SDS), 0.002 M dithiothrei...
Murray MJ, Doran RE, Pfeiffer CJ, Tyler DE, Moore JN, Sriranganathan N.Isolated segments of left dorsal colon and a side-to-side colocolostomy (between the left ventral colon and left dorsal colon) were surgically created in 6 adult ponies. Four segments, each separated by an empty segment, were inoculated (20 ml) with 1 of the following 4 solutions: phosphate buffered saline solution (PBSS)/1% polyethylene glycol (PEG); purified cholera toxin in PBSS/1% PEG (5 micrograms cholera toxin/ml of PBSS/1% PEG); lyophilized Salmonella typhimurium UCD 1755 culture lysate, reconstituted in PBSS/1% PEG; and viable S typhimurium UCD 1755 (10(8) organisms/ml of PBSS/1% PEG)....
Weaver RE, Sharif M, Livingston LA, Andrews KL, Fuller CJ.The objective of this study was to assess whether macroscopically normal articular cartilage taken from joints containing focal osteoarthritic lesions is histologically similar to articular cartilage taken from macroscopically normal joints. Metacarpophalangeal, proximal interphalangeal, and distal interphalangeal joints were obtained from 10 horses following euthanasia. Gross articular cartilage damage was scored and the cartilage assigned to one of two groups: (1) macroscopically normal cartilage from normal joints (control) and (2) macroscopically normal cartilage from diseased joints in wh...
Turek JJ, Templeton CB, Bottoms GD, Fessler JF.Endotoxic shock was induced in 5 ponies by intraperitoneal injections of 20, 40, 60, 80, and 80 micrograms of Escherichia coli endotoxin (LPS)/kg of body weight at 0, 6, 12, 18, and 24 hours, respectively. At 24 hours, the ponies also were given 20 micrograms of LPS/kg via catheter in the left ventricle of the heart. A 2nd group of 4 ponies was given 1.1 mg of flunixin meglumine (FM)/kg, IV, at 6, 12, 18, and 24 hours just before the corresponding LPS injection. Two hours after the 24-hour LPS injection, the ponies in both groups were anesthetized, the lungs were perfused with fixative, and po...
Sledge DG, Miller DL, Styer EL, Hydrick HA, Baldwin CA.Granulomatous dermatitis in horses has been linked to many etiologies, including various parasites, fungi, and bacteria. Idiopathic forms of granulomatous inflammation-producing diseases, some of which are localized to the skin, also have been reported in horses. Herein we describe a case of recurrent equine granulomatous skin disease characterized by intranuclear viral inclusions within macrophages and giant cells. The histologic changes were primarily noted in the deep dermis and included multifocal to coalescing areas of necrosis marked by histiocytic cell infiltration and presence of giant...
Scott DW.Resumen- Dos caballos adultos manifestaron un cuadro prurítico y de dolor asociado con una dermatitis generalizada de evolución rápida y consistente en la presencia de pápulas, pústulas y costras. El examen microscópico de extensiones citológicas a partir del exudado purulento reveló la presencia de numerosos queratinocitos acantoliticos, neutrófilos no degenerados y ausencia de microorganismos, lo que sugirió un diagnóstico de pénfigo foliáceo. Las biopsias de piel mostraron dermatofitosis, marcada acantolisis y crecióTrichophyton equinum en cultivos fúngicos. Las lesiones en a...
Anderson BG, Anderson WD.The use of methyl methacrylate corrosion-casts has made it possible to examine the intracranial microvasculature on a three-dimensional scale with the scanning electron microscope. By this means we have compared regions of four cerebral and cerebellar arteries among three domestic animal species. The results of this study suggest that there are from one to three different levels of interarteriolar anastomosis between branches of the same or adjacent vessels. In the horse and ox anastomoses were demonstrated (1) at the level of the precapillary arterioles, (2) along the arterioles, and (3) betw...
Ferreira C, Palhares MS, de Melo UP, Chiarini-Garcia H, Maranhão RPA, Gheller VA, Leme FOP.To determine the effect of the inclusion method on the histomorphometric evaluation of the gastrointestinal mucosa of horses, jejunum samples were collected using flank laparotomy. Sixteen mixed breed healthy adult horses, including four males and 12 females, aged 4-14 years with an average body weight of 248.40 ± 2.28 kg, were used. Jejunal biopsies were collected and analyzed by light microscopy using two methods: group 1 comprised biopsies fixed using 10% neutral formalin and embedded in paraffin; biopsies in group 2 were fixed in 2.5% glutaraldehyde in 0.1 M phosphate buffer pH 7.2, follo...
Borkent D, Smith S, Dixon PM.Peripheral caries (PC) has recently been shown to affect over half of UK and Australian horses. Objective: To examine affected cheek teeth histologically and ultrastructurally, to assess the possible route(s) of carious infection into the dental tissues and to further describe the pathological changes in affected teeth. Methods: Descriptive pathological study. Methods: Four control and 16 cheek teeth with different grades of PC were examined grossly, histologically and by electron microscopy. Results: Cariogenic bacteria from plaque entered peripheral cementum perpendicular to the sides of tee...
Bengtsdotter EA, Ekman S, Andersen PH.Inguinal pain, unexplained hind limb lameness, back pain or behavioural problems in geldings could be attributable to painful neuromas that develop as a consequence of crushing and severing the testicular nerves during castration. The presence of neuroma in this anatomical location has never been reported, hence the knowledge of possible clinical relevance is limited. The aim of this study was to histologically investigate the testicular nerves at the castration site in geldings for the presence of neuromas. Proximal spermatic cord remnants were collected from 20 geldings admitted to routine p...
Cummings JF, de Lahunta A, Summers BA, Mohammed HO, Divers TJ, Valentine BA, Trembicki-Graves K.Equine motor neuron disease (EMND) is a sporadic, progressive neurodegenerative disorder that has been identified recently in horses of different breeds in North America. The cause is unknown. Pathologic changes which occur in spinal and certain brain stem motor neurons include chromatolysis, swelling, neurofilamentous accumulation, and development of eosinophilic cytoplasmic inclusions. Punctate eosinophilic inclusions, the type usually encountered in degenerating neurons, resembled Bunina bodies at the light microscopic level, but differed in their ultrastructural composition. These and less...
Cummings JF, de Lahunta A, Timoney JF.Four cases of neuritis of the cauda equina (NCE) were studied by light and electron microscopy. Examination of sacral intradural rootlets revealed inflammatory cell infiltrates and an array of myelinated fiber changes which included myelin stripping by invading mononuclear cells and macrophages, as well as splitting and vesiculation of myelin lamellae without obvious participation by leukocytes. More distally in the extradural roots, there was marked granulomatous inflammation, and demyelinative changes were overshadowed by widespread evidence of irreversible axon damage. In all cases, unusual...
Grant DC, Westropp JL, Shiraki R, Ruby AL.Laser lithotripsy has been used as an alternative to surgical removal of uroliths. Objective: To describe the procedure and efficacy of laser lithotripsy for removal of lower urinary tract uroliths in horses. Additionally, the ultrastructure and the differences in mineralogy and microstructure from 1 successful and 1 unsuccessful laser lithotripsy case are described. Methods: Six client-owned horses with 7 episodes of naturally occurring urocystoliths, urethroliths, or both. Methods: Retrospective study of all horses treated between 2006 and 2008 by laser lithotripsy. All horses were sedated f...
Nikles SA, Heath TJ.The intestine of horses differs from that of most other domestic animals in having a huge ascending colon and cecum, which together act as a large fermentation vat. The lymph drainage from this intestine occurs through a complex network of lymph vessels and lymph nodes, of which there are several thousand. The pathways taken by lymph through these vessels and nodes were studied by tracing injections of dye, by examining Microfil casts, and with light and transmission electron microscopy. Lymph vessels transporting lymph from the intestinal wall generally terminate on a single node within a gro...
